An enzyme system that catalyzes the fixing of nitrogen in soil bacteria and blue-green algae (CYANOBACTERIA). EC 1.18.6.1.
A non-heme iron-sulfur protein isolated from Clostridium pasteurianum and other bacteria. It is a component of NITROGENASE, which is active in nitrogen fixation, and consists of two subunits with molecular weights of 59.5 kDa and 50.7 kDa, respectively.
Acetylene is not typically considered a medical term, but rather a chemical compound (C2H2) commonly used in industrial and laboratory settings for its high energy content and reactivity, which may have various applications in medicine such as wound healing and surgical procedures, but it is not a medical diagnosis or disease.
The process in certain BACTERIA; FUNGI; and CYANOBACTERIA converting free atmospheric NITROGEN to biologically usable forms of nitrogen, such as AMMONIA; NITRATES; and amino compounds.
A genus of gram-negative, aerobic bacteria found in soil and water. Its organisms occur singly, in pairs or irregular clumps, and sometimes in chains of varying lengths.
A species of gram-negative, aerobic bacteria first isolated from soil in Vineland, New Jersey. Ammonium and nitrate are used as nitrogen sources by this bacterium. It is distinguished from other members of its genus by the ability to use rhamnose as a carbon source. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)
A non-heme iron-sulfur protein isolated from Clostridium pasteurianum and other bacteria. It is a component of NITROGENASE along with molybdoferredoxin and is active in nitrogen fixation.
Gram-negative, non-motile, capsulated, gas-producing rods found widely in nature and associated with urinary and respiratory infections in humans.
Vibrio- to spiral-shaped phototrophic bacteria found in stagnant water and mud exposed to light.
Iron-containing proteins that transfer electrons, usually at a low potential, to flavoproteins; the iron is not present as in heme. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
Dithionite. The dithionous acid ion and its salts.
Non-pathogenic ovoid to rod-shaped bacteria that are widely distributed and found in fresh water as well as marine and hypersaline habitats.
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
Ethane is an organic compound, specifically a hydrocarbon (aliphatic alkane), with the chemical formula C2H6, which consists of two carbon atoms and six hydrogen atoms, and is the second simplest alkane after methane. However, it's important to note that ethane is not a medical term or concept; it's a basic chemistry term.
A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
Organic compounds that are acyclic and contain three acid groups. A member of this class is citric acid which is the first product formed by reaction of pyruvate and oxaloacetate. (From Lehninger, Principles of Biochemistry, 1982, p443)
A phylum of oxygenic photosynthetic bacteria comprised of unicellular to multicellular bacteria possessing CHLOROPHYLL a and carrying out oxygenic PHOTOSYNTHESIS. Cyanobacteria are the only known organisms capable of fixing both CARBON DIOXIDE (in the presence of light) and NITROGEN. Cell morphology can include nitrogen-fixing heterocysts and/or resting cells called akinetes. Formerly called blue-green algae, cyanobacteria were traditionally treated as ALGAE.
A species of motile, free-living, gram-negative bacteria that occur in the soil. They are aerobic or microaerophilic and are sometimes capable of nitrogen fixation.
Methionine Sulfoximine is a toxic compound that functions as an inhibitor of methionine metabolism, being formed through the oxidation of methionine by the enzyme methionine sulfoxide reductase.
Proteins that have one or more tightly bound metal ions forming part of their structure. (Dorland, 28th ed)
A low-molecular-weight (16,000) iron-free flavoprotein containing one molecule of flavin mononucleotide (FMN) and isolated from bacteria grown on an iron-deficient medium. It can replace ferredoxin in all the electron-transfer functions in which the latter is known to serve in bacterial cells.
A metallic element with the atomic symbol V, atomic number 23, and atomic weight 50.94. It is used in the manufacture of vanadium steel. Prolonged exposure can lead to chronic intoxication caused by absorption usually via the lungs.
Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.
The functional hereditary units of BACTERIA.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
A genus of gram-negative, rod-shaped, phototrophic bacteria found in aquatic environments. Internal photosynthetic membranes are present as lamellae underlying the cytoplasmic membrane.
Proteins found in any species of bacterium.
A genus in the family ACETOBACTERACEAE comprised of acetate-oxidizing bacteria.
A genus of motile or nonmotile gram-positive bacteria of the family Clostridiaceae. Many species have been identified with some being pathogenic. They occur in water, soil, and in the intestinal tract of humans and lower animals.
Tungsten. A metallic element with the atomic symbol W, atomic number 74, and atomic weight 183.85. It is used in many manufacturing applications, including increasing the hardness, toughness, and tensile strength of steel; manufacture of filaments for incandescent light bulbs; and in contact points for automotive and electrical apparatus.
A genus of gram-negative, aerobic, rod-shaped bacteria that activate PLANT ROOT NODULATION in leguminous plants. Members of this genus are nitrogen-fixing and common soil inhabitants.
A family of signal transducing adaptor proteins that control the METABOLISM of NITROGEN. They are primarily found in prokaryotes.
Proteins, usually acting in oxidation-reduction reactions, containing iron but no porphyrin groups. (Lehninger, Principles of Biochemistry, 1993, pG-10)
A genus of CYANOBACTERIA consisting of trichomes that are untapered with conspicuous constrictions at cross-walls. A firm individual sheath is absent, but a soft covering is often present. Many species are known worldwide as major components of freshwater PLANKTON and also of many saline lakes. The species ANABAENA FLOS-AQUAE is responsible for acute poisonings of various animals.
A genus of gram-negative, facultatively anaerobic bacteria including species which are often associated with grasses (POACEAE) and which fix nitrogen as well as species which anaerobically degrade toluene and other mono-aromatic hydrocarbons.
A species of ANABAENA that can form SPORES called akinetes.
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
An acidifying agent that has expectorant and diuretic effects. Also used in etching and batteries and as a flux in electroplating.
Imides are organic compounds characterized by the presence of a functional group with the structure R-C(=O)-N-R', where R and R' are organic radicals, often found in pharmaceuticals, dyes, and as intermediates in chemical synthesis.
The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
An enzyme that catalyzes the conversion of ATP, L-glutamate, and NH3 to ADP, orthophosphate, and L-glutamine. It also acts more slowly on 4-methylene-L-glutamate. (From Enzyme Nomenclature, 1992) EC 6.3.1.2.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.
The complete absence, or (loosely) the paucity, of gaseous or dissolved elemental oxygen in a given place or environment. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
A hemoglobin-like oxygen-binding hemeprotein present in the nitrogen-fixing root nodules of leguminous plants. The red pigment has a molecular weight approximately 1/4 that of hemoglobin and has been suggested to act as an oxido-reduction catalyst in symbiotic nitrogen fixation.
The interference in synthesis of an enzyme due to the elevated level of an effector substance, usually a metabolite, whose presence would cause depression of the gene responsible for enzyme synthesis.
The relationship between two different species of organisms that are interdependent; each gains benefits from the other or a relationship between different species where both of the organisms in question benefit from the presence of the other.
A form-genus of unicellular coccoid to rod-shaped CYANOBACTERIA, in the order Chroococcales. Three different clusters of strains from diverse habitats are included.
The rate dynamics in chemical or physical systems.
Organic and inorganic compounds that contain iron as an integral part of the molecule.
Adenosine 5'-(trihydrogen diphosphate). An adenine nucleotide containing two phosphate groups esterified to the sugar moiety at the 5'-position.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
A family of gram-negative aerobic bacteria consisting of ellipsoidal to rod-shaped cells that occur singly, in pairs, or in chains.
The absence of light.
Genus of BACTERIA in the family Frankiaceae. They are nitrogen-fixing root-nodule symbionts of many species of woody dicotyledonous plants.
Used as an electron carrier in place of the flavine enzyme of Warburg in the hexosemonophosphate system and also in the preparation of SUCCINIC DEHYDROGENASE.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Small molecules that are required for the catalytic function of ENZYMES. Many VITAMINS are coenzymes.
An enzyme found in bacteria. It catalyzes the reduction of FERREDOXIN and other substances in the presence of molecular hydrogen and is involved in the electron transport of bacterial photosynthesis.
Enzymes that transfer the ADP-RIBOSE group of NAD or NADP to proteins or other small molecules. Transfer of ADP-ribose to water (i.e., hydrolysis) is catalyzed by the NADASES. The mono(ADP-ribose)transferases transfer a single ADP-ribose. POLY(ADP-RIBOSE) POLYMERASES transfer multiple units of ADP-ribose to protein targets, building POLY ADENOSINE DIPHOSPHATE RIBOSE in linear or branched chains.
An amino acid that inhibits phosphate-activated glutaminase and interferes with glutamine metabolism. It is an antineoplastic antibiotic produced by an unidentified species of Streptomyces from Peruvian soil. (From Merck Index, 11th ed)

Correlation of activity regulation and substrate recognition of the ADP-ribosyltransferase that regulates nitrogenase activity in Rhodospirillum rubrum. (1/904)

In Rhodospirillum rubrum, nitrogenase activity is regulated posttranslationally through the ADP-ribosylation of dinitrogenase reductase by dinitrogenase reductase ADP-ribosyltransferase (DRAT). Several DRAT variants that are altered both in the posttranslational regulation of DRAT activity and in the ability to recognize variants of dinitrogenase reductase have been found. This correlation suggests that these two properties are biochemically connected.  (+info)

The presence of ADP-ribosylated Fe protein of nitrogenase in Rhodobacter capsulatus is correlated with cellular nitrogen status. (2/904)

The photosynthetic bacterium Rhodobacter capsulatus has been shown to regulate its nitrogenase by covalent modification via the reversible ADP-ribosylation of Fe protein in response to darkness or the addition of external NH4+. Here we demonstrate the presence of ADP-ribosylated Fe protein under a variety of steady-state growth conditions. We examined the modification of Fe protein and nitrogenase activity under three different growth conditions that establish different levels of cellular nitrogen: batch growth with limiting NH4+, where the nitrogen status is externally controlled; batch growth on relatively poor nitrogen sources, where the nitrogen status is internally controlled by assimilatory processes; and continuous culture. When cultures were grown to stationary phase with different limiting concentrations of NH4+, the ADP-ribosylation state of Fe protein was found to correlate with cellular nitrogen status. Additionally, actively growing cultures (grown with N2 or glutamate), which had an intermediate cellular nitrogen status, contained a portion of their Fe protein in the modified state. The correlation between cellular nitrogen status and ADP-ribosylation state was corroborated with continuous cultures grown under various degrees of nitrogen limitation. These results show that in R. capsulatus the modification system that ADP-ribosylates nitrogenase in the short term in response to abrupt changes in the environment is also capable of modifying nitrogenase in accordance with long-term cellular conditions.  (+info)

Classes of Anabaena variabilis mutants with oxygen-sensitive nitrogenase activity. (3/904)

Mutants of Anabaena variabilis deficient in the envelope glycolipids of heterocysts have no or very low nitrogenase activity when assayed aerobically. Revertants capable of aerobic growth on N2 have increased quantities of these glycolipids. Among mutants which require fixed nitrogen for growth in air and which have a normal complement of glycolipids, one expresses high nitrogenase activity at low oxygen tension. Three others show high nitrogenase activity only in the presence of dithionite and are therefore impaired in electron transfer.  (+info)

Azorhizobium caulinodans PII and GlnK proteins control nitrogen fixation and ammonia assimilation. (4/904)

We herein report that Azorhizobium caulinodans PII and GlnK are not necessary for glutamine synthetase (GS) adenylylation whereas both proteins are required for complete GS deadenylylation. The disruption of both glnB and glnK resulted in a high level of GS adenylylation under the condition of nitrogen fixation, leading to ammonium excretion in the free-living state. PII and GlnK also controlled nif gene expression because NifA activated nifH transcription and nitrogenase activity was derepressed in glnB glnK double mutants, but not in wild-type bacteria, grown in the presence of ammonia.  (+info)

MgATP-independent hydrogen evolution catalysed by nitrogenase: an explanation for the missing electron(s) in the MgADP-AlF4 transition-state complex. (5/904)

When the MoFe (Kp1) and Fe (Kp2) component proteins of Klebsiella pneumoniae nitrogenase are incubated with MgADP and AlF4(-) in the presence of dithionite as a reducing agent, a stable putative transition-state complex is produced [Yousafzai and Eady (1997) Biochem. J. 326, 637-640]. Surprisingly, the EPR signal associated with reduced Kp2 is not detectable, but Kp1 retains the S=3/2 EPR signal arising from the dithionite reduced state of the MoFe cofactor centre of the protein. This is consistent with the [Fe4S4] centre of the Fe protein in the complex being oxidized, and similar observations have been made with the complex of Azotobacter vinelandii [Spee, Arendsen, Wassink, Marritt, Hagen and Haaker (1998) FEBS Lett. 432, 55-58]. No satisfactory explanation for the fate of the electrons lost by Kp2 has been forthcoming. However, we report here that during the preparation of the MgADP-AlF4 K. pneumoniae complex under argon, H2 was evolved in amounts corresponding to one half of the FeMoco content of the Kp1 (FeMoco is the likely catalytic site of nitrogenase with a composition Mo:Fe7:S9:homocitrate). This is surprising, since activity is observed during incubation in the absence of MgATP, normally regarded as being essential for nitrogenase function, and in the presence of MgADP, a strong competitive inhibitor of nitrogenase. The formation of H2 by nitrogenase in the absence of AlF4(-) was also observed in reaction mixtures containing MgADP but not MgATP. The reaction showed saturation kinetics when Kp1 was titrated with increasing amounts of Kp2 and, at saturation, the amount of H2 formed was stoichiometric with the FeMoco content of Kp1. The dependence of the rate of formation of H2 on [MgADP] was inconsistent with the activity arising from MgATP contamination. We conclude that MgATP is not obligatory for H+ reduction by nitrogenase since MgADP supports a very low rate of hydrogen evolution.  (+info)

Organization and expression of nitrogen-fixation genes in the aerobic nitrogen-fixing unicellular cyanobacterium Synechococcus sp. strain RF-1. (6/904)

Sixteen nif and 'nif-associated' genes (expressed only under conditions of nitrogen fixation) in Synechococcus sp. strain RF-1 have been cloned and sequenced. All of the nif and nif-associated genes identified in Synechococcus RF-1 were arranged in a continuous cluster spanning approximately 18 kb and containing seven operons. The nifH operon (nifH-nifD-nifK) has been reported previously. nifB, fdxN, nifS, nifU and nifP were found to be located upstream of the nifH operon. nifB-fdxN-nifS-nifU were expressed as an operon. A nifP-like gene was found to be located just upstream of nifB. nifE, nifN, nifX, nifW and the nif-associated hesA, hesB and 'fdx' were found to be located downstream from nifK. The genes located downstream from nifK are arranged nifE-nifN-nifX-orf-nifW-hesA-hesB-'+ ++fdx' and span approximately 7 kb. The function of the ORF situated between nifX and nifW is not known. However, it was identified as a counterpart of ORF-2 in Anabaena sp. strain PCC 7120 based on the deduced amino acid sequence. Northern hybridization and primer extension analysis indicated that the nif and nif-associated genes are organized in nifE-nifN, nifX-orf, nifW-hesA-hesB and 'fdx'-containing operons, respectively. According to the results of this study and previous reports, the genes are expressed in a rhythmic pattern with peaks during the dark phase when the culture is grown in a 12 h light/12 h dark regimen. The rhythm persisted after the culture was transferred to continuous illumination.  (+info)

Requirement of NifX and other nif proteins for in vitro biosynthesis of the iron-molybdenum cofactor of nitrogenase. (7/904)

The iron-molybdenum cofactor (FeMo-co) of nitrogenase contains molybdenum, iron, sulfur, and homocitrate in a ratio of 1:7:9:1. In vitro synthesis of FeMo-co has been established, and the reaction requires an ATP-regenerating system, dithionite, molybdate, homocitrate, and at least NifB-co (the metabolic product of NifB), NifNE, and dinitrogenase reductase (NifH). The typical in vitro FeMo-co synthesis reaction involves mixing extracts from two different mutant strains of Azotobacter vinelandii defective in the biosynthesis of cofactor or an extract of a mutant strain complemented with the purified missing component. Surprisingly, the in vitro synthesis of FeMo-co with only purified components failed to generate significant FeMo-co, suggesting the requirement for one or more other components. Complementation of these assays with extracts of various mutant strains demonstrated that NifX has a role in synthesis of FeMo-co. In vitro synthesis of FeMo-co with purified components is stimulated approximately threefold by purified NifX. Complementation of these assays with extracts of A. vinelandii DJ42. 48 (DeltanifENX DeltavnfE) results in a 12- to 15-fold stimulation of in vitro FeMo-co synthesis activity. These data also demonstrate that apart from the NifX some other component(s) is required for the cofactor synthesis. The in vitro synthesis of FeMo-co with purified components has allowed the detection, purification, and identification of an additional component(s) required for the synthesis of cofactor.  (+info)

Carbon and ammonia metabolism of Spirillum lipoferum. (8/904)

Intact cells and extracts from Spirillum lipoferum rapidly oxidized malate, succinate, lactate, and pyruvate. Glucose, galactose, fructose, acetate, and citrate did not increase the rate of O2 uptake by cells above the endogenous rate. Cells grown on NH+/4 oxidized the various substrates at about the same rate as did cells grown on N2. Added oxidized nicotinamide adenine dinucleotide generally enhanced O2 uptake by extracts supplied organic acids, whereas oxidized nicotinamide adenine dinucleotide phosphate had little effect. Nitrogenase synthesis repressed by growth of cells in the presence of NH+/4 was derepressed by methionine sulfoximine or methionine sulfone. The total glutamine synthetase activity from N2-grown cells was about eight times that from NH+/4-grown S. lipoferum; the response of glutamate dehydrogenase was the opposite. The total glutamate synthetase activity from N2-grown S. lipoferum was 1.4 to 2.6 times that from NH+/4-grown cells. The levels of poly-beta-hydroxybutyrate and beta-hydroxybutyrate dehydrogenase were elevated in cells grown on N2 as compared with those grown on NH+/4. Cell-free extracts capable of reducing C2H2 have been prepared; both Mg2+ and Mn2+ are required for good activity.  (+info)

Nitrogenase is not a medical term, but a biological term used in the field of microbiology and biochemistry. It refers to an enzyme complex found in certain bacteria and archaea that have the ability to fix nitrogen gas (N2) from the atmosphere into ammonia (NH3), a form of nitrogen that can be utilized by plants and other organisms for growth and development. This process is known as biological nitrogen fixation, which is essential for maintaining the global nitrogen cycle and supporting life on Earth.

The medical field may refer to nitrogenase in relation to human health in the context of understanding the role of nitrogen-fixing bacteria in soil fertility and their impact on agriculture and food production. However, there is no direct medical definition or application for nitrogenase.

Molybdoferredoxin is not a widely recognized medical term, but it is a term used in biochemistry and molecular biology to describe a type of protein that contains molybdenum and iron-sulfur clusters as cofactors. These proteins are involved in various redox reactions in the body, particularly in the metabolism of certain amino acids, nucleotides, and other small molecules.

Molybdoferredoxins are found in many organisms, including bacteria, archaea, and eukaryotes (including humans). In humans, molybdoferredoxins play important roles in several metabolic pathways, such as the oxidation of sulfite to sulfate and the reduction of nitrate to nitrite.

Deficiencies or mutations in molybdoferredoxin-related genes can lead to various metabolic disorders, including molybdenum cofactor deficiency, a rare genetic disorder that affects multiple enzymes requiring molybdenum as a cofactor.

Acetylene is defined as a colorless, highly flammable gas with a distinctive odor, having the chemical formula C2H2. It is the simplest and lightest hydrocarbon in which two carbon atoms are bonded together by a triple bond. Acetylene is used as a fuel in welding and cutting torches, and it can also be converted into other chemicals, such as vinyl acetate and acetic acid. In medical terms, acetylene is not a substance that is commonly used or discussed.

Nitrogen fixation is a process by which nitrogen gas (N2) in the air is converted into ammonia (NH3) or other chemically reactive forms, making it available to plants and other organisms for use as a nutrient. This process is essential for the nitrogen cycle and for the growth of many types of plants, as most plants cannot utilize nitrogen gas directly from the air.

In the medical field, nitrogen fixation is not a commonly used term. However, in the context of microbiology and infectious diseases, some bacteria are capable of fixing nitrogen and this ability can contribute to their pathogenicity. For example, certain species of bacteria that colonize the human body, such as those found in the gut or on the skin, may be able to fix nitrogen and use it for their own growth and survival. In some cases, these bacteria may also release fixed nitrogen into the environment, which can have implications for the ecology and health of the host and surrounding ecosystems.

'Azotobacter' is a genus of free-living nitrogen-fixing bacteria commonly found in soil and water. These bacteria are capable of converting atmospheric nitrogen into ammonia, a process known as nitrogen fixation, which can then be used by plants for growth. The name 'Azotobacter' comes from the Greek words "azoto," meaning without life, and "bakterion," meaning little rod.

The bacteria are characterized by their ability to form cysts or thick-walled resting stages that allow them to survive in unfavorable conditions such as dryness or high temperatures. They are also known for their large size, typically ranging from 1.5 to 2.5 micrometers in diameter, and their motility, which is powered by a single polar flagellum.

'Azotobacter' species are important contributors to the nitrogen cycle in soil and play a crucial role in maintaining soil fertility. They have also been studied for their potential use in various industrial applications, such as the production of biofuels, bioplastics, and enzymes.

'Azotobacter vinelandii' is a species of free-living, nitrogen-fixing bacteria that is commonly found in soil and freshwater environments. The name 'Azotobacter' comes from the Greek words "azoto," meaning "nitrogen," and "bakterion," meaning "rod" or "staff," while "vinelandii" refers to Vineland, New Jersey, where the bacterium was first isolated.

'Azotobacter vinelandii' is known for its ability to convert atmospheric nitrogen gas (N2) into ammonia (NH3), a process called nitrogen fixation. This makes it an important contributor to the global nitrogen cycle and a valuable tool in agricultural and industrial applications.

In addition to its nitrogen-fixing abilities, 'Azotobacter vinelandii' is also known for its resistance to desiccation, high tolerance to oxygen levels, and ability to produce various extracellular polysaccharides and enzymes. These characteristics make it a popular model organism for studying bacterial metabolism, stress responses, and genetic regulation.

Overall, 'Azotobacter vinelandii' is a fascinating and important microorganism with significant implications for our understanding of the nitrogen cycle, environmental biology, and potential industrial applications.

I'm sorry for any confusion, but "Molybdenum" is not a medical term. It is an element with the symbol Mo and atomic number 42 on the periodic table. Molybdenum is used in various industries, including medicine, for example in the production of surgical instruments and some prosthetics due to its strength and resistance to corrosion. However, it is not a term used to describe a medical condition or bodily process. If you have any questions related to elements and their uses in medicine, I'd be happy to help with those!

Dinitrogenase reductase is a protein involved in the process of nitrogen fixation in certain bacteria and archaea. It is responsible for delivering electrons to the enzyme dinitrogenase, which converts atmospheric nitrogen (N2) into ammonia (NH3), making it available for use by living organisms. Dinitrogenase reductase contains a cluster of iron and sulfur atoms that facilitate the transfer of electrons. The combined action of dinitrogenase reductase and dinitrogenase allows these microorganisms to utilize nitrogen from the atmosphere as a source of nitrogen for growth, making them important contributors to the global nitrogen cycle.

"Klebsiella pneumoniae" is a medical term that refers to a type of bacteria belonging to the family Enterobacteriaceae. It's a gram-negative, encapsulated, non-motile, rod-shaped bacterium that can be found in various environments, including soil, water, and the gastrointestinal tracts of humans and animals.

"Klebsiella pneumoniae" is an opportunistic pathogen that can cause a range of infections, particularly in individuals with weakened immune systems or underlying medical conditions. It's a common cause of healthcare-associated infections, such as pneumonia, urinary tract infections, bloodstream infections, and wound infections.

The bacterium is known for its ability to produce a polysaccharide capsule that makes it resistant to phagocytosis by white blood cells, allowing it to evade the host's immune system. Additionally, "Klebsiella pneumoniae" has developed resistance to many antibiotics, making infections caused by this bacterium difficult to treat and a growing public health concern.

"Rhodospirillum rubrum" is a gram-negative, facultatively anaerobic, photosynthetic bacteria species. It is commonly found in freshwater and soil environments, and it has the ability to carry out both photosynthesis and respiration, depending on the availability of light and oxygen. The bacteria contain bacteriochlorophyll and carotenoid pigments, which give them a pinkish-red color, hence the name "rubrum." They are known to be important organisms in the study of photosynthesis, nitrogen fixation, and other metabolic processes.

Ferredoxins are iron-sulfur proteins that play a crucial role in electron transfer reactions in various biological systems, particularly in photosynthesis and nitrogen fixation. They contain one or more clusters of iron and sulfur atoms (known as the iron-sulfur cluster) that facilitate the movement of electrons between different molecules during metabolic processes.

Ferredoxins have a relatively simple structure, consisting of a polypeptide chain that binds to the iron-sulfur cluster. This simple structure allows ferredoxins to participate in a wide range of redox reactions and makes them versatile electron carriers in biological systems. They can accept electrons from various donors and transfer them to different acceptors, depending on the needs of the cell.

In photosynthesis, ferredoxins play a critical role in the light-dependent reactions by accepting electrons from photosystem I and transferring them to NADP+, forming NADPH. This reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) is then used in the Calvin cycle for carbon fixation and the production of glucose.

In nitrogen fixation, ferredoxins help transfer electrons to the nitrogenase enzyme complex, which reduces atmospheric nitrogen gas (N2) into ammonia (NH3), making it available for assimilation by plants and other organisms.

Overall, ferredoxins are essential components of many metabolic pathways, facilitating electron transfer and energy conversion in various biological systems.

Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.

The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.

Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.

Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.

Nitrogen is not typically referred to as a medical term, but it is an element that is crucial to medicine and human life.

In a medical context, nitrogen is often mentioned in relation to gas analysis, respiratory therapy, or medical gases. Nitrogen (N) is a colorless, odorless, and nonreactive gas that makes up about 78% of the Earth's atmosphere. It is an essential element for various biological processes, such as the growth and maintenance of organisms, because it is a key component of amino acids, nucleic acids, and other organic compounds.

In some medical applications, nitrogen is used to displace oxygen in a mixture to create a controlled environment with reduced oxygen levels (hypoxic conditions) for therapeutic purposes, such as in certain types of hyperbaric chambers. Additionally, nitrogen gas is sometimes used in cryotherapy, where extremely low temperatures are applied to tissues to reduce pain, swelling, and inflammation.

However, it's important to note that breathing pure nitrogen can be dangerous, as it can lead to unconsciousness and even death due to lack of oxygen (asphyxiation) within minutes.

Dithionite is a chemical compound with the formula Na2S2O4. It is also known as sodium hydrosulfite or sodium dithionite. Dithionite is a white crystalline solid that is highly soluble in water and is commonly used as a reducing agent in various industrial and laboratory applications, including the reduction of iron and copper salts, the bleaching of textiles and pulp, and the removal of sulfur dioxide from flue gases.

In medical contexts, dithionite may be used as a reducing agent in some pharmaceutical preparations or as an antidote for certain types of poisoning. However, it is important to note that dithionite can be toxic and corrosive in concentrated forms, and should be handled with care.

Rhodobacter capsulatus is not a medical term, but a species name in the field of microbiology. It refers to a type of purple nonsulfur bacteria that is capable of photosynthesis and can be found in freshwater and soil environments. These bacteria are known for their ability to switch between using light and organic compounds as sources of energy, depending on the availability of each. They have been studied for their potential applications in biotechnology and renewable energy production.

While not directly related to medical definitions, some research has explored the potential use of Rhodobacter capsulatus in bioremediation and wastewater treatment due to its ability to break down various organic compounds. However, it is not a pathogenic organism and does not have any direct relevance to human health or disease.

I'm sorry for any confusion, but "Hydrogen" is not a medical term. It is a chemical element with the symbol H and atomic number 1. It is the lightest and most abundant chemical element in the universe, making up about 75% of its elemental mass.

In a medical context, hydrogen can be discussed in terms of molecular hydrogen (H2) which has been studied for potential therapeutic benefits. Some research explores its use as an antioxidant and anti-inflammatory agent, but more studies are needed to confirm these effects and understand the mechanisms behind them.

Ethane is not a medical term, but it is a chemical compound that is part of the human environment. Ethane is a hydrocarbon, which means it contains only hydrogen and carbon atoms. Specifically, ethane is made up of two carbon atoms and six hydrogen atoms (C2H6). It is a colorless gas at room temperature and has no smell or taste.

In the context of human health, ethane is not considered to be harmful in small amounts. However, exposure to high levels of ethane can cause respiratory irritation and other symptoms. Ethane is also a greenhouse gas, which means that it contributes to global warming when released into the atmosphere.

Ethane is produced naturally during the breakdown of organic matter, such as plants and animals. It is also produced in small amounts during the digestion of food in the human body. However, most ethane used in industry is extracted from natural gas and petroleum deposits. Ethane is used as a fuel and as a raw material in the production of plastics and other chemicals.

Ammonia is a colorless, pungent-smelling gas with the chemical formula NH3. It is a compound of nitrogen and hydrogen and is a basic compound, meaning it has a pH greater than 7. Ammonia is naturally found in the environment and is produced by the breakdown of organic matter, such as animal waste and decomposing plants. In the medical field, ammonia is most commonly discussed in relation to its role in human metabolism and its potential toxicity.

In the body, ammonia is produced as a byproduct of protein metabolism and is typically converted to urea in the liver and excreted in the urine. However, if the liver is not functioning properly or if there is an excess of protein in the diet, ammonia can accumulate in the blood and cause a condition called hyperammonemia. Hyperammonemia can lead to serious neurological symptoms, such as confusion, seizures, and coma, and is treated by lowering the level of ammonia in the blood through medications, dietary changes, and dialysis.

Tricarboxylic acids, also known as TCA cycle or citric acid cycle, is a series of chemical reactions used by all living cells to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into carbon dioxide and water in the form of ATP. This process is an important part of cellular respiration and occurs in the mitochondria. The cycle involves eight steps that result in the production of two molecules of ATP, reduced coenzymes NADH and FADH2, and the release of three molecules of carbon dioxide.

The tricarboxylic acids involved in this cycle are:

1. Citric acid (also known as citrate)
2. Cis-aconitic acid
3. Isocitric acid
4. Oxalosuccinic acid (an intermediate that is not regenerated)
5. α-Ketoglutaric acid (also known as alpha-ketoglutarate)
6. Succinyl-CoA
7. Succinic acid (also known as succinate)
8. Fumaric acid
9. Malic acid
10. Oxaloacetic acid (also known as oxalacetate)

These acids play a crucial role in the energy production and metabolism of living organisms.

Cyanobacteria, also known as blue-green algae, are a type of bacteria that obtain their energy through photosynthesis, similar to plants. They can produce oxygen and contain chlorophyll a, which gives them a greenish color. Some species of cyanobacteria can produce toxins that can be harmful to humans and animals if ingested or inhaled. They are found in various aquatic environments such as freshwater lakes, ponds, and oceans, as well as in damp soil and on rocks. Cyanobacteria are important contributors to the Earth's oxygen-rich atmosphere and play a significant role in the global carbon cycle.

'Azospirillum brasilense' is a species of free-living, nitrogen-fixing bacteria that is commonly found in the soil and in the roots of various plants. It belongs to the genus Azospirillum and is known for its ability to promote plant growth through a process called bacterial colonization. The bacteria colonize the root system of the plant and enhance nutrient uptake, leading to improved growth and yield. Additionally, 'Azospirillum brasilense' can convert atmospheric nitrogen into ammonia, making it available to the plants as a natural fertilizer. It is widely used in agricultural practices as a bioinoculant to improve crop productivity and sustainability.

Methionine Sulfoximine (MSO) is not a medical term itself, but it is a compound that has been used in research and scientific studies. It's a stable analogue of the essential amino acid methionine, which can be found in some foods like sesame seeds, Brazil nuts, and fish.

Methionine Sulfoximine has been used in research to study the metabolism and transport of methionine in cells and organisms. It is also known for its ability to inhibit the enzyme cystathionine β-synthase (CBS), which plays a role in the metabolism of homocysteine, an amino acid associated with cardiovascular disease when present at high levels.

However, Methionine Sulfoximine is not used as a therapeutic agent or medication in humans due to its potential toxicity and lack of established clinical benefits.

Metalloproteins are proteins that contain one or more metal ions as a cofactor, which is required for their biological activity. These metal ions play crucial roles in the catalytic function, structural stability, and electron transfer processes of metalloproteins. The types of metals involved can include iron, zinc, copper, magnesium, calcium, or manganese, among others. Examples of metalloproteins are hemoglobin (contains heme-bound iron), cytochrome c (contains heme-bound iron and functions in electron transfer), and carbonic anhydrase (contains zinc and catalyzes the conversion between carbon dioxide and bicarbonate).

Flavodoxin is not strictly a medical term, but it is a term used in biochemistry and molecular biology. Flavodoxins are small electron transfer proteins that contain a non-heme iron atom bound to a organic molecule called flavin mononucleotide (FMN). They play a role in various biological processes such as photosynthesis, nitrogen fixation and respiration where they function as electron carriers. Flavodoxins can undergo reversible oxidation and reduction, and this property allows them to transfer electrons between different enzymes during metabolic reactions. They are not specific to human physiology, but can be found in various organisms including bacteria, algae, and plants.

I'm sorry for any confusion, but "Vanadium" is not a medical term. It is a chemical element with the symbol V and atomic number 23. Vanadium is not a biological or medical concept in itself, but it can be found in some living organisms in small amounts as a trace element.

However, vanadium compounds have been studied in the context of potential medicinal uses, such as insulin mimetic properties and possible effects on diabetes management. But these are still in the research stage and not yet established medical facts or practices. Therefore, I would be happy to provide more information about vanadium from a chemical or materials science perspective, but it is not typically considered within the realm of medical definitions.

Argon is a colorless, odorless, tasteless, and nonreactive noble gas that occurs in the Earth's atmosphere. It is chemically inert and is extracted from air by fractional distillation. Argon is used in various applications such as illumination, welding, and as a shielding gas in manufacturing processes.

In medical terms, argon is not commonly used as a therapeutic agent or medication. However, it has been used in some medical procedures such as argon laser therapy for the treatment of certain eye conditions like diabetic retinopathy and age-related macular degeneration. In these procedures, an argon laser is used to seal off leaking blood vessels or destroy abnormal tissue in the eye.

Overall, while argon has important uses in medical procedures, it is not a medication or therapeutic agent that is commonly administered directly to patients.

A bacterial gene is a segment of DNA (or RNA in some viruses) that contains the genetic information necessary for the synthesis of a functional bacterial protein or RNA molecule. These genes are responsible for encoding various characteristics and functions of bacteria such as metabolism, reproduction, and resistance to antibiotics. They can be transmitted between bacteria through horizontal gene transfer mechanisms like conjugation, transformation, and transduction. Bacterial genes are often organized into operons, which are clusters of genes that are transcribed together as a single mRNA molecule.

It's important to note that the term "bacterial gene" is used to describe genetic elements found in bacteria, but not all genetic elements in bacteria are considered genes. For example, some DNA sequences may not encode functional products and are therefore not considered genes. Additionally, some bacterial genes may be plasmid-borne or phage-borne, rather than being located on the bacterial chromosome.

Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."

In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).

The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.

Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.

Quaternary ammonium compounds (QACs) are a group of disinfectants and antiseptics that contain a nitrogen atom surrounded by four organic groups, resulting in a charged "quat" structure. They are widely used in healthcare settings due to their broad-spectrum activity against bacteria, viruses, fungi, and spores. QACs work by disrupting the cell membrane of microorganisms, leading to their death. Common examples include benzalkonium chloride and cetyltrimethylammonium bromide. It is important to note that some microorganisms have developed resistance to QACs, and they may not be effective against all types of pathogens.

Electron Spin Resonance (ESR) Spectroscopy, also known as Electron Paramagnetic Resonance (EPR) Spectroscopy, is a technique used to investigate materials with unpaired electrons. It is based on the principle of absorption of energy by the unpaired electrons when they are exposed to an external magnetic field and microwave radiation.

In this technique, a sample is placed in a magnetic field and microwave radiation is applied. The unpaired electrons in the sample absorb energy and change their spin state when the energy of the microwaves matches the energy difference between the spin states. This absorption of energy is recorded as a function of the magnetic field strength, producing an ESR spectrum.

ESR spectroscopy can provide information about the number, type, and behavior of unpaired electrons in a sample, as well as the local environment around the electron. It is widely used in physics, chemistry, and biology to study materials such as free radicals, transition metal ions, and defects in solids.

Rhodopseudomonas is a genus of gram-negative, rod-shaped bacteria that are capable of photosynthesis. These bacteria contain bacteriochlorophyll and can use light as an energy source in the absence of oxygen, which makes them facultative anaerobes. They typically inhabit freshwater and soil environments, and some species are able to fix nitrogen gas. Rhodopseudomonas species are known to cause various infections in humans, including bacteremia, endocarditis, and respiratory tract infections, particularly in immunocompromised individuals. However, such infections are relatively rare.

Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.

Bacterial proteins can be classified into different categories based on their function, such as:

1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.

Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.

"Gluconacetobacter" is a genus of gram-negative, aerobic, rod-shaped bacteria that are commonly found in various environments such as soil, water, and plant surfaces. They are known for their ability to oxidize sugars and alcohols into organic acids, which makes them important in industrial processes like the production of vinegar and biofuels. In a medical context, they are not typically associated with human diseases, but there have been rare reports of infections in immunocompromised individuals.

'Clostridium' is a genus of gram-positive, rod-shaped bacteria that are widely distributed in nature, including in soil, water, and the gastrointestinal tracts of animals and humans. Many species of Clostridium are anaerobic, meaning they can grow and reproduce in environments with little or no oxygen. Some species of Clostridium are capable of producing toxins that can cause serious and sometimes life-threatening illnesses in humans and animals.

Some notable species of Clostridium include:

* Clostridium tetani, which causes tetanus (also known as lockjaw)
* Clostridium botulinum, which produces botulinum toxin, the most potent neurotoxin known and the cause of botulism
* Clostridium difficile, which can cause severe diarrhea and colitis, particularly in people who have recently taken antibiotics
* Clostridium perfringens, which can cause food poisoning and gas gangrene.

It is important to note that not all species of Clostridium are harmful, and some are even beneficial, such as those used in the production of certain fermented foods like sauerkraut and natto. However, due to their ability to produce toxins and cause illness, it is important to handle and dispose of materials contaminated with Clostridium species carefully, especially in healthcare settings.

I'm sorry for any confusion, but 'Tungsten' is not a medical term. It is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth, and it has many industrial uses due to its hardness, high density, and high melting point.

In the context of medicine or healthcare, tungsten may be encountered in certain medical devices, such as X-ray tubes and electrodes, where its properties are utilized for their durability and heat resistance. However, it is not a term that would typically have a formal medical definition.

Rhizobium is not a medical term, but rather a term used in microbiology and agriculture. It refers to a genus of gram-negative bacteria that can fix nitrogen from the atmosphere into ammonia, which can then be used by plants as a nutrient. These bacteria live in the root nodules of leguminous plants (such as beans, peas, and clover) and form a symbiotic relationship with them.

The host plant provides Rhizobium with carbon sources and a protected environment within the root nodule, while the bacteria provide the plant with fixed nitrogen. This mutualistic interaction plays a crucial role in maintaining soil fertility and promoting plant growth.

While Rhizobium itself is not directly related to human health or medicine, understanding its symbiotic relationship with plants can have implications for agricultural practices, sustainable farming, and global food security.

PII nitrogen regulatory proteins are a type of signal transduction protein involved in the regulation of nitrogen metabolism in bacteria and archaea. They are named "PII" because they contain two identical subunits, each with a molecular weight of approximately 12 kilodaltons. These proteins play a crucial role in sensing and responding to changes in the energy status and nitrogen availability within the cell.

The PII protein is composed of three domains: the T-domain, which binds ATP and ADP; the N-domain, which binds 2-oxoglutarate (an indicator of carbon and nitrogen status); and the B-domain, which is involved in signal transduction. The PII protein can exist in different conformational states depending on whether it is bound to ATP or ADP, and this affects its ability to interact with downstream effectors.

One of the primary functions of PII proteins is to regulate the activity of glutamine synthetase (GS), an enzyme that catalyzes the conversion of glutamate to glutamine. When nitrogen is abundant, PII proteins bind to GS and stimulate its activity, promoting the assimilation of ammonia into organic compounds. Conversely, when nitrogen is scarce, PII proteins dissociate from GS, allowing it to be inhibited by other regulatory proteins.

PII proteins can also interact with other enzymes and regulators involved in nitrogen metabolism, such as nitrogenase, uridylyltransferase/uridylyl-removing enzyme (UT/UR), and transcriptional regulators. Through these interactions, PII proteins help to coordinate the cell's response to changes in nitrogen availability and energy status, ensuring that resources are allocated efficiently and effectively.

Non-heme iron proteins are a type of iron-containing protein that do not contain heme as their prosthetic group. Heme is a complex molecule consisting of an iron atom contained in the center of a porphyrin ring, which is a large organic molecule made up of four pyrrole rings joined together. In contrast, non-heme iron proteins contain iron that is bound to the protein in other ways, such as through coordination with amino acid side chains or through association with an iron-sulfur cluster.

Examples of non-heme iron proteins include ferritin and transferrin, which are involved in the storage and transport of iron in the body, respectively. Ferritin is a protein that stores iron in a form that is safe and bioavailable for use by the body. Transferrin, on the other hand, binds to iron in the intestines and transports it to cells throughout the body.

Non-heme iron proteins are important for many biological processes, including oxygen transport, electron transfer, and enzyme catalysis. They play a crucial role in energy metabolism, DNA synthesis, and other essential functions.

Anabaena is a genus of cyanobacteria, also known as blue-green algae. These bacteria are capable of photosynthesis and can form colonies that resemble fine filaments or hair-like structures. Some species of Anabaena are able to fix nitrogen from the atmosphere, making them important contributors to the nitrogen cycle in aquatic ecosystems. In some cases, certain species of Anabaena can produce toxins that can be harmful to other organisms, including humans and animals.

It's worth noting that while Anabaena is a widely used and well-established genus name, recent research has suggested that the traditional classification system for cyanobacteria may not accurately reflect their evolutionary relationships. As a result, some scientists have proposed alternative classification schemes that may lead to changes in the way these organisms are named and classified in the future.

Azoarcus is a genus of bacteria that have the ability to degrade aromatic compounds, including toluene and benzene. These bacteria are found in various environments such as soil, water, and the rhizosphere of plants. They are gram-negative, motile rods that are capable of denitrification, which means they can use nitrate as an electron acceptor during respiration instead of oxygen. Some species of Azoarcus can also fix nitrogen, making them important contributors to the nitrogen cycle in their environments.

The name "Azoarcus" comes from the Greek word "azo," meaning nitrogen, and the Latin word "arcus," meaning bow or arc, referring to the shape of the nitrate reduction pathway in these bacteria.

It's worth noting that while Azoarcus species have potential applications in bioremediation and wastewater treatment, some strains can also cause disease in plants, so their use in certain environments must be carefully considered.

Anabaena variabilis is a species of cyanobacteria (blue-green algae) that can form filamentous colonies. It is capable of fixing atmospheric nitrogen, making it an important contributor to the nitrogen cycle in aquatic environments. The term 'variabilis' refers to the variable size and shape of its cells.

Here's a simple medical definition:

Anabaena variabilis: A species of filamentous cyanobacteria known for its ability to fix nitrogen, contributing to the nitrogen cycle in aquatic environments. Its cells can vary in size and shape.

In the context of medicine, iron is an essential micromineral and key component of various proteins and enzymes. It plays a crucial role in oxygen transport, DNA synthesis, and energy production within the body. Iron exists in two main forms: heme and non-heme. Heme iron is derived from hemoglobin and myoglobin in animal products, while non-heme iron comes from plant sources and supplements.

The recommended daily allowance (RDA) for iron varies depending on age, sex, and life stage:

* For men aged 19-50 years, the RDA is 8 mg/day
* For women aged 19-50 years, the RDA is 18 mg/day
* During pregnancy, the RDA increases to 27 mg/day
* During lactation, the RDA for breastfeeding mothers is 9 mg/day

Iron deficiency can lead to anemia, characterized by fatigue, weakness, and shortness of breath. Excessive iron intake may result in iron overload, causing damage to organs such as the liver and heart. Balanced iron levels are essential for maintaining optimal health.

Ammonium chloride is an inorganic compound with the formula NH4Cl. It is a white crystalline salt that is highly soluble in water and can be produced by combining ammonia (NH3) with hydrochloric acid (HCl). Ammonium chloride is commonly used as a source of hydrogen ions in chemical reactions, and it has a variety of industrial and medical applications.

In the medical field, ammonium chloride is sometimes used as a expectorant to help thin and loosen mucus in the respiratory tract, making it easier to cough up and clear from the lungs. It may also be used to treat conditions such as metabolic alkalosis, a condition characterized by an excess of base in the body that can lead to symptoms such as confusion, muscle twitching, and irregular heartbeat.

However, it is important to note that ammonium chloride can have side effects, including stomach upset, nausea, vomiting, and diarrhea. It should be used under the guidance of a healthcare professional and should not be taken in large amounts or for extended periods of time without medical supervision.

I'm not aware of a medical definition for the term "imides." It is a chemical term that refers to a specific type of organic compound containing a functional group with the structure R-C(=O)-N-R', where R and R' are organic groups, and the nitrogen atom is bonded to two organic groups. This term is more commonly used in chemistry and biochemistry rather than in medical contexts.

The Electron Transport Chain (ETC) is a series of complexes in the inner mitochondrial membrane that are involved in the process of cellular respiration. It is the final pathway for electrons derived from the oxidation of nutrients such as glucose, fatty acids, and amino acids to be transferred to molecular oxygen. This transfer of electrons drives the generation of a proton gradient across the inner mitochondrial membrane, which is then used by ATP synthase to produce ATP, the main energy currency of the cell.

The electron transport chain consists of four complexes (I-IV) and two mobile electron carriers (ubiquinone and cytochrome c). Electrons from NADH and FADH2 are transferred to Complex I and Complex II respectively, which then pass them along to ubiquinone. Ubiquinone then transfers the electrons to Complex III, which passes them on to cytochrome c. Finally, cytochrome c transfers the electrons to Complex IV, where they combine with oxygen and protons to form water.

The transfer of electrons through the ETC is accompanied by the pumping of protons from the mitochondrial matrix to the intermembrane space, creating a proton gradient. The flow of protons back across the inner membrane through ATP synthase drives the synthesis of ATP from ADP and inorganic phosphate.

Overall, the electron transport chain is a crucial process for generating energy in the form of ATP in the cell, and it plays a key role in many metabolic pathways.

Adenosine Triphosphate (ATP) is a high-energy molecule that stores and transports energy within cells. It is the main source of energy for most cellular processes, including muscle contraction, nerve impulse transmission, and protein synthesis. ATP is composed of a base (adenine), a sugar (ribose), and three phosphate groups. The bonds between these phosphate groups contain a significant amount of energy, which can be released when the bond between the second and third phosphate group is broken, resulting in the formation of adenosine diphosphate (ADP) and inorganic phosphate. This process is known as hydrolysis and can be catalyzed by various enzymes to drive a wide range of cellular functions. ATP can also be regenerated from ADP through various metabolic pathways, such as oxidative phosphorylation or substrate-level phosphorylation, allowing for the continuous supply of energy to cells.

Glutamate-ammonia ligase, also known as glutamine synthetase, is an enzyme that plays a crucial role in nitrogen metabolism. It catalyzes the formation of glutamine from glutamate and ammonia in the presence of ATP, resulting in the conversion of ammonia to a less toxic form. This reaction is essential for maintaining nitrogen balance in the body and for the synthesis of various amino acids, nucleotides, and other biomolecules. The enzyme is widely distributed in various tissues, including the brain, liver, and muscle, and its activity is tightly regulated through feedback inhibition by glutamine and other metabolites.

Oxygen is a colorless, odorless, tasteless gas that constitutes about 21% of the earth's atmosphere. It is a crucial element for human and most living organisms as it is vital for respiration. Inhaled oxygen enters the lungs and binds to hemoglobin in red blood cells, which carries it to tissues throughout the body where it is used to convert nutrients into energy and carbon dioxide, a waste product that is exhaled.

Medically, supplemental oxygen therapy may be provided to patients with conditions such as chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, or other medical conditions that impair the body's ability to extract sufficient oxygen from the air. Oxygen can be administered through various devices, including nasal cannulas, face masks, and ventilators.

Iron-sulfur proteins are a group of metalloproteins that contain iron and sulfur atoms in their active centers. These clusters of iron and sulfur atoms, also known as iron-sulfur clusters, can exist in various forms, including Fe-S, 2Fe-2S, 3Fe-4S, and 4Fe-4S structures. The iron atoms are coordinated to the protein through cysteine residues, while the sulfur atoms can be in the form of sulfide (S2-) or sulfane (-S-).

These proteins play crucial roles in many biological processes, such as electron transfer, redox reactions, and enzyme catalysis. They are found in various organisms, from bacteria to humans, and are involved in a wide range of cellular functions, including energy metabolism, photosynthesis, nitrogen fixation, and DNA repair.

Iron-sulfur proteins can be classified into several categories based on their structure and function, such as ferredoxins, Rieske proteins, high-potential iron-sulfur proteins (HiPIPs), and radical SAM enzymes. Dysregulation or mutations in iron-sulfur protein genes have been linked to various human diseases, including neurodegenerative disorders, cancer, and mitochondrial disorders.

Anaerobiosis is a state in which an organism or a portion of an organism is able to live and grow in the absence of molecular oxygen (O2). In biological contexts, "anaerobe" refers to any organism that does not require oxygen for growth, and "aerobe" refers to an organism that does require oxygen for growth.

There are two types of anaerobes: obligate anaerobes, which cannot tolerate the presence of oxygen and will die if exposed to it; and facultative anaerobes, which can grow with or without oxygen but prefer to grow in its absence. Some organisms are able to switch between aerobic and anaerobic metabolism depending on the availability of oxygen, a process known as "facultative anaerobiosis."

Anaerobic respiration is a type of metabolic process that occurs in the absence of molecular oxygen. In this process, organisms use alternative electron acceptors other than oxygen to generate energy through the transfer of electrons during cellular respiration. Examples of alternative electron acceptors include nitrate, sulfate, and carbon dioxide.

Anaerobic metabolism is less efficient than aerobic metabolism in terms of energy production, but it allows organisms to survive in environments where oxygen is not available or is toxic. Anaerobic bacteria are important decomposers in many ecosystems, breaking down organic matter and releasing nutrients back into the environment. In the human body, anaerobic bacteria can cause infections and other health problems if they proliferate in areas with low oxygen levels, such as the mouth, intestines, or deep tissue wounds.

Leghemoglobin is a type of protein known as a hemeprotein, found in the root nodules of leguminous plants (plants belonging to the family Fabaceae or Leguminosae). These root nodules are formed through a symbiotic relationship with nitrogen-fixing bacteria called Rhizobia.

The primary function of leghemoglobin is to facilitate the process of nitrogen fixation by maintaining an optimal oxygen concentration within the root nodule cells, where the Rhizobia reside. By binding and releasing oxygen reversibly, leghemoglobin protects the nitrogen-fixing enzyme, nitrogenase, from being inactivated by excess oxygen. This ensures that the Rhizobia can effectively convert atmospheric nitrogen gas (N2) into ammonia (NH3), which is then utilized by the plant for its growth and development.

In summary, leghemoglobin is a crucial protein in the process of biological nitrogen fixation, allowing leguminous plants to grow without the need for added nitrogen fertilizers.

Enzyme repression is a type of gene regulation in which the production of an enzyme is inhibited or suppressed, thereby reducing the rate of catalysis of the chemical reaction that the enzyme facilitates. This process typically occurs when the end product of the reaction binds to the regulatory protein, called a repressor, which then binds to the operator region of the operon (a group of genes that are transcribed together) and prevents transcription of the structural genes encoding for the enzyme. Enzyme repression helps maintain homeostasis within the cell by preventing the unnecessary production of enzymes when they are not needed, thus conserving energy and resources.

In the context of medicine and biology, symbiosis is a type of close and long-term biological interaction between two different biological organisms. Generally, one organism, called the symbiont, lives inside or on another organism, called the host. This interaction can be mutually beneficial (mutualistic), harmful to the host organism (parasitic), or have no effect on either organism (commensal).

Examples of mutualistic symbiotic relationships in humans include the bacteria that live in our gut and help us digest food, as well as the algae that live inside corals and provide them with nutrients. Parasitic symbioses, on the other hand, involve organisms like viruses or parasitic worms that live inside a host and cause harm to it.

It's worth noting that while the term "symbiosis" is often used in popular culture to refer to any close relationship between two organisms, in scientific contexts it has a more specific meaning related to long-term biological interactions.

I'm sorry for any confusion, but "Cyanothece" is not a medical term or concept. It is actually the name of a genus of cyanobacteria (blue-green algae), which are capable of both oxygenic photosynthesis and nitrogen fixation. These bacteria have attracted interest in various scientific fields due to their potential applications in bioenergy, bioremediation, and basic biological research.

If you have any questions related to medical terminology or health-related topics, I'd be happy to help!

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Iron compounds refer to chemical substances that contain iron (Fe) combined with other elements. Iron is an essential mineral for the human body, playing a crucial role in various bodily functions such as oxygen transport, DNA synthesis, and energy production.

There are several types of iron compounds, including:

1. Inorganic iron salts: These are commonly used in dietary supplements and fortified foods to treat or prevent iron deficiency anemia. Examples include ferrous sulfate, ferrous gluconate, and ferric iron.
2. Heme iron: This is the form of iron found in animal products such as meat, poultry, and fish. It is more easily absorbed by the body compared to non-heme iron from plant sources.
3. Non-heme iron: This is the form of iron found in plant-based foods such as grains, legumes, fruits, and vegetables. It is not as well-absorbed as heme iron but can be enhanced by consuming it with vitamin C or other organic acids.

It's important to note that excessive intake of iron compounds can lead to iron toxicity, which can cause serious health problems. Therefore, it's essential to follow recommended dosages and consult a healthcare professional before taking any iron supplements.

Adenosine diphosphate (ADP) is a chemical compound that plays a crucial role in energy transfer within cells. It is a nucleotide, which consists of a adenosine molecule (a sugar molecule called ribose attached to a nitrogenous base called adenine) and two phosphate groups.

In the cell, ADP functions as an intermediate in the conversion of energy from one form to another. When a high-energy phosphate bond in ADP is broken, energy is released and ADP is converted to adenosine triphosphate (ATP), which serves as the main energy currency of the cell. Conversely, when ATP donates a phosphate group to another molecule, it is converted back to ADP, releasing energy for the cell to use.

ADP also plays a role in blood clotting and other physiological processes. In the coagulation cascade, ADP released from damaged red blood cells can help activate platelets and initiate the formation of a blood clot.

Gene expression regulation in bacteria refers to the complex cellular processes that control the production of proteins from specific genes. This regulation allows bacteria to adapt to changing environmental conditions and ensure the appropriate amount of protein is produced at the right time.

Bacteria have a variety of mechanisms for regulating gene expression, including:

1. Operon structure: Many bacterial genes are organized into operons, which are clusters of genes that are transcribed together as a single mRNA molecule. The expression of these genes can be coordinately regulated by controlling the transcription of the entire operon.
2. Promoter regulation: Transcription is initiated at promoter regions upstream of the gene or operon. Bacteria have regulatory proteins called sigma factors that bind to the promoter and recruit RNA polymerase, the enzyme responsible for transcribing DNA into RNA. The binding of sigma factors can be influenced by environmental signals, allowing for regulation of transcription.
3. Attenuation: Some operons have regulatory regions called attenuators that control transcription termination. These regions contain hairpin structures that can form in the mRNA and cause transcription to stop prematurely. The formation of these hairpins is influenced by the concentration of specific metabolites, allowing for regulation of gene expression based on the availability of those metabolites.
4. Riboswitches: Some bacterial mRNAs contain regulatory elements called riboswitches that bind small molecules directly. When a small molecule binds to the riboswitch, it changes conformation and affects transcription or translation of the associated gene.
5. CRISPR-Cas systems: Bacteria use CRISPR-Cas systems for adaptive immunity against viruses and plasmids. These systems incorporate short sequences from foreign DNA into their own genome, which can then be used to recognize and cleave similar sequences in invading genetic elements.

Overall, gene expression regulation in bacteria is a complex process that allows them to respond quickly and efficiently to changing environmental conditions. Understanding these regulatory mechanisms can provide insights into bacterial physiology and help inform strategies for controlling bacterial growth and behavior.

Acetobacteraceae is a family of gram-negative, aerobic bacteria that are capable of converting ethanol into acetic acid, a process known as oxidative fermentation. These bacteria are commonly found in environments such as fruits, flowers, and the gut of insects. They are also used in the industrial production of vinegar and other products. Some members of this family can cause food spoilage or infections in humans with weakened immune systems.

I am not aware of a medical definition for the term "darkness." In general, darkness refers to the absence of light. It is not a term that is commonly used in the medical field, and it does not have a specific clinical meaning. If you have a question about a specific medical term or concept, I would be happy to try to help you understand it.

"Frankia" is not a term that has a widely accepted medical definition. However, in the field of microbiology, "Frankia" refers to a genus of nitrogen-fixing bacteria that can form symbiotic relationships with various plants, particularly those in the order Fagales such as alders and casuarinas. These bacteria are capable of converting atmospheric nitrogen into ammonia, which the host plant can then use for growth. This relationship is beneficial to both the bacterium and the plant, as the plant provides carbon sources and a protected environment for the bacterium to live in.

In a medical context, "Frankia" may be mentioned in relation to rare cases of infection in humans, particularly in individuals with weakened immune systems. However, such infections are extremely uncommon.

Methylphenazonium methosulfate is not a medication itself, but rather a reagent used in the production and pharmacological research of certain medications. It's commonly used as a redox mediator, which means it helps to facilitate electron transfer in chemical reactions. In medical contexts, it may be used in the laboratory synthesis or testing of some drugs.

It's important to note that methylphenazonium methosulfate is not intended for direct medical use in humans or animals. Always consult with a healthcare professional or trusted medical source for information regarding specific medications and their uses.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Coenzymes are small organic molecules that assist enzymes in catalyzing chemical reactions within cells. They typically act as carriers of specific atoms or groups of atoms during enzymatic reactions, facilitating the conversion of substrates into products. Coenzymes often bind temporarily to enzymes at the active site, forming an enzyme-coenzyme complex.

Coenzymes are usually derived from vitamins or minerals and are essential for maintaining proper metabolic functions in the body. Examples of coenzymes include nicotinamide adenine dinucleotide (NAD+), flavin adenine dinucleotide (FAD), and coenzyme A (CoA). When a coenzyme is used up in a reaction, it must be regenerated or replaced for the enzyme to continue functioning.

In summary, coenzymes are vital organic compounds that work closely with enzymes to facilitate biochemical reactions, ensuring the smooth operation of various metabolic processes within living organisms.

Hydrogenase is not a medical term per se, but a biochemical term. It is used to describe an enzyme that catalyzes the reversible conversion between molecular hydrogen (H2) and protons (H+) or vice versa. These enzymes are found in certain bacteria, algae, and archaea, and they play a crucial role in their energy metabolism, particularly in processes like hydrogen production and consumption.

While not directly related to medical terminology, understanding the function of hydrogenase can be important in fields such as microbiology, molecular biology, and environmental science, which can have implications for human health in areas like infectious diseases, biofuels, and waste management.

ADP Ribose Transferases are a group of enzymes that catalyze the transfer of ADP-ribose groups from donor molecules, such as NAD+ (nicotinamide adenine dinucleotide), to specific acceptor molecules. This transfer process plays a crucial role in various cellular processes, including DNA repair, gene expression regulation, and modulation of protein function.

The reaction catalyzed by ADP Ribose Transferases can be represented as follows:

Donor (NAD+ or NADP+) + Acceptor → Product (NR + ADP-ribosylated acceptor)

There are two main types of ADP Ribose Transferases based on their function and the type of modification they perform:

1. Poly(ADP-ribose) polymerases (PARPs): These enzymes add multiple ADP-ribose units to a single acceptor protein, forming long, linear, or branched chains known as poly(ADP-ribose) (PAR). PARylation is involved in DNA repair, genomic stability, and cell death pathways.
2. Monomeric ADP-ribosyltransferases: These enzymes transfer a single ADP-ribose unit to an acceptor protein, which is called mono(ADP-ribosyl)ation. This modification can regulate protein function, localization, and stability in various cellular processes, such as signal transduction, inflammation, and stress response.

Dysregulation of ADP Ribose Transferases has been implicated in several diseases, including cancer, neurodegenerative disorders, and cardiovascular diseases. Therefore, understanding the function and regulation of these enzymes is essential for developing novel therapeutic strategies to target these conditions.

Diazoxide is a medication that is used to treat hypoglycemia (low blood sugar) in certain circumstances, such as in patients with pancreatic tumors or other conditions that cause excessive insulin production. Diazooxonorleucine is not a recognized medical term or a known medication. It appears that there may be some confusion regarding the name of this compound.

Diazoxide itself is a vasodilator, which means it works by relaxing and widening blood vessels. This can help to lower blood pressure and improve blood flow to various parts of the body. Diazoxide is typically given intravenously (through an IV) in a hospital setting.

It's possible that "diazooxonorleucine" may be a typographical error or a misunderstanding of the name of a different compound. If you have more information about where you encountered this term, I may be able to provide further clarification.

... nitrogenase, vanadium (V) nitrogenase, and iron-only (Fe) nitrogenase. Molybdenum nitrogenase, which can be found in ... Vanadium nitrogenase and iron-only nitrogenase can both be found in select species of Azotobacter as an alternative nitrogenase ... For example, H2 competes with N2 but not acetylene for nitrogenase (leading to overestimates of nitrogenase by ARA). Bottle or ... No crystallographic analysis has been reported on substrate bound to nitrogenase. Nitrogenase is able to reduce acetylene, but ...
... vinelandii vanadium nitrogenase was resolved in 2017 (PDB: 5N6Y​). Compared to Mo nitrogenase, V nitrogenase replaces one ... Unlike molybdenum nitrogenase, vanadium nitrogenase can also reduce carbon monoxide to ethylene, ethane and propane but both ... Vanadium nitrogenase has an α2β2Ύ2 subunit structure while molybdenum nitrogenase has an α2β2 structure. Though the structural ... Like molybdenum nitrogenase, vanadium nitrogenase is easily oxidized and is thus only active under anaerobic conditions. ...
Nitrogenase Zumft WG, Mortenson LE (March 1975). "The nitrogen-fixing complex of bacteria". Biochimica et Biophysica Acta (BBA ... Nitrogenase (flavodoxin) (EC 1.19.6.1) is an enzyme with systematic name reduced flavodoxin:dinitrogen oxidoreductase (ATP- ...
Burk, D. "Nitrogenase". Ergebnisse der Enzymforschung. 3: 23-56. Lineweaver H, Burk D, Deming, W E (1934). "The dissociation ... constant of nitrogen-nitrogenase in Azobacter". J. Amer. Chem. Soc. 56: 225-230. doi:10.1021/ja01316a071.{{cite journal}}: CS1 ...
Burk, D. "Nitrogenase". Ergebnisse der Enzymforschung. 3: 23-56. Eisenthal, R.; Cornish-Bowden, A. (1974). "The direct linear ... This is not necessarily the case! Lineweaver H, Burk D, Deming WE (1934). "The dissociation constant of nitrogen-nitrogenase in ...
Molybdenum-dependent nitrogenase is the most commonly present nitrogenase. The different types of nitrogenase can be determined ... nifH has two similar genes anfH and vnfH that also encode for the nitrogenase reductase component of the nitrogenase complex. ... Peterson RB, Wolk CP (December 1978). "High recovery of nitrogenase activity and of Fe-labeled nitrogenase in heterocysts ... Nitrogenase consist of two proteins, a catalytic iron-dependent protein, commonly referred to as MoFe protein and a reducing ...
Ribbe MW, Hu Y, Hodgson KO, Hedman B (April 2014). "Biosynthesis of nitrogenase metalloclusters". Chemical Reviews. 114 (8): ...
... (FeMo cofactor) is the primary cofactor of nitrogenase. Nitrogenase is the enzyme that catalyzes the conversion of ... Isolation of the FeMo cofactor from nitrogenase is done through centrifugal sedimentation of nitrogenase into the MoFe protein ... ISBN 978-0-444-50965-9. Kim J, Rees DC (September 1992). "Structural models for the metal centers in the nitrogenase molybdenum ... The interstitial carbon remains associated with the FeMo cofactor after insertion into the nitrogenase, The central carbon atom ...
nifK encodes for B-subunit of Component 1 of nitrogenase. nifD encodes for alpha subunit of component 1 of nitrogenase. nifH ... EhNifS and EhNifU were found to be necessary and sufficient for Fe-S clusters of non-nitrogenase Fe-S proteins to form under ... Mo-Fe-co catalytic site for nitrogenase.) nifQ is not absolutely essential. nifJ operon:The nifJ gene encodes for the pyruvate- ... This enzyme is involved in electron transfer to nitrogenase. nifUSVM operon: The nifS, nifV and nifM genes encode for a protein ...
Subject of this work include nitric oxide synthase, cytochrome P450, nickel-iron hydrogenase, and nitrogenase. In 2012, he ... Hoffman BM, Lukoyanov D, Dean DR, Seefeldt LC (2013). "Nitrogenase: A Draft Mechanism". Accounts of Chemical Research. 46 (2): ...
The best-studied nitrogenase up-to-date is Mo nitrogenase with M-cluster and P-cluster bearing important roles in substrate ... Nitrogenase is a metallozyme with essential function in the biological nitrogen fixation reaction. The M-cluster ([MoFe7S9C- ... The active site of Mo nitrogenase is the M-cluster, a metal-sulfur cluster containing a carbide at its core. Within the ... Wiig JA, Hu Y, Chung Lee C, Ribbe MW (September 2012). "Radical SAM-dependent carbon insertion into the nitrogenase M-cluster ...
"Biosynthesis of Nitrogenase Metalloclusters". Chemical Reviews. 114 (8): 4063-4080. doi:10.1021/cr400463x. PMC 3999185. PMID ...
Burges BK, Lowe DJ (1996). "Mechanism of Molybdenum Nitrogenase". Chemical Reviews. 96 (7): 2983-3011. doi:10.1021/cr950055x. ... the Mo-Fe protein of nitrogenase catalyzes the conversion of N2 to NH3 in nitrogen fixation. Of more relevance to human biology ...
Nitrogenase reveals its inner secrets". Science. 297 (5587): 1654-1655. doi:10.1126/science.1076659. PMID 12215632. S2CID ...
This is reaction is catalyzed by nitrogenase which is inhibited by oxygen, ammonia and a high N:C ratio. H2 is an emerging, but ... Kelley BC, Jouanneau Y, Vignais PM (August 1979). "Nitrogenase activity in Rhodopseudomonas sulfidophila". Archives of ...
Nitrogenase, an enzyme that contains a MoFe cluster, can be leveraged to fix atmospheric nitrogen, i.e. convert nitrogen gas ... Milton, Ross D.; Minteer, Shelley D. (2019-12-17). "Nitrogenase Bioelectrochemistry for Synthesis Applications". Accounts of ...
"Iron(V) Nitride Mimics Nitrogenase Activity". cen.acs.org. 2011-02-28. Retrieved 2021-05-21. Nishibayashi, Yoshiaki (2011-06-23 ...
Nitrogenase is expressed under nitrogen limitation. Normally, the expression is regulated via negative feedback from the ... All diazotrophs contain iron-molybdenum or iron-vanadium nitrogenase systems. Two of the most studied systems are those of ... Aerobes-these species require oxygen to grow, yet their nitrogenase is still debilitated if exposed to oxygen. Azotobacter ... and supplied at a rate that will not harm the nitrogenase. Frankias-much less is known about/to these 'actinorhizal' nitrogen ...
The reason for this is that the enzyme responsible for nitrogen fixation in diazotrophs, nitrogenase, uses iron as a cofactor. ... Oxygen is especially toxic to nitrogenase. One way in which nitrogen-fixing cyanobacteria, such as those in the genera "Nostoc ... one of the ways by which Crocosphaera watsonii protects its nitrogenase from oxygen is through the adaptation of a diel rhythm ... and the iron can be used in other processes such as nitrogen fixation by nitrogenase. This mechanism reduces the iron ...
Other organisms require additional metals as enzyme cofactors, such as vanadium in the nitrogenase of the nitrogen-fixing ... Eady RR (July 1988). "The vanadium-containing nitrogenase of Azotobacter". BioFactors. 1 (2): 111-6. PMID 3076437. Chan MK, ...
Lee SC, Holm RH (April 2003). "Speculative synthetic chemistry and the nitrogenase problem". Proceedings of the National ...
Azonexus fungiphilus possesses the nitrogenase-gene nifH. "LSPN LPSN/". Retrieved 2013-08-15. "Straininfo of Azonexus ...
The UCYN-A1 sublineage has an abundance of nitrogenase in a range of 104 - 107 copies of nifH per litre. UCYN-A1 and UCYN-A2 ... Church MJ, Short CM, Jenkins BD, Karl DM, Zehr JP (September 2005). "Temporal patterns of nitrogenase gene (nifH) expression in ... The oligotypes of A. thalassa are based on its nitrogenase (nifH) sequences, and reveal thirteen positions of variance (entropy ... Zehr JP, Turner PJ (2001-01-01). "Nitrogen fixation: Nitrogenase genes and gene expression". Methods in Microbiology. Marine ...
doi:10.1021/ja01318a036.. Lineweaver H, Burk D, Deming, W E (1934). "The dissociation constant of nitrogen-nitrogenase in ...
A prominent application of this method its use to identify the central carbon atom in FeMo cofactor of Nitrogenase (see section ... Another approach in this field concerns comparative studies of different forms of nitrogenase enzymes with FeMoco and FeVco ... Nitrogenase. Serena DeBeer and her group study this remarkable system comprising a FeMo cofactor (FeMoco) as its active site, ... "Resolving the structure of the E 1 state of Mo nitrogenase through Mo and Fe K-edge EXAFS and QM/MM calculations". Chemical ...
Two main enzymes produce hydrogen in microbes, hydrogenase and nitrogenase; Cyanothece has both enzymes. The nitrogenase fixes ... PCC 7425's nitrogenase cluster is arranged differently from the other five strains and can only fix nitrogen anaerobically. ... In a very energy-intensive process, nitrogenase is first synthesized and then takes N2 from the air, combining it with protons ... Decreasing the oxygen in the cell allows the oxygen-sensitive nitrogenase to fix nitrogen from the air for the organism's needs ...
Lineweaver H, Burk D, Deming, W E (1934). "The dissociation constant of nitrogen-nitrogenase in Azobacter". J. Amer. Chem. Soc ...
Lineweaver H, Burk D, Deming, W E (1934). "The dissociation constant of nitrogen-nitrogenase in Azobacter". Journal of the ...
Like purple sulfur bacteria, they can regulate the activity of nitrogenase post-translationally in response to ammonia ... and the evolution of nitrogenase". Free Radical Biology and Medicine. Early Life on Earth and Oxidative Stress. 140: 250-259. ...
November 2011). "X-ray emission spectroscopy evidences a central carbon in the nitrogenase iron-molybdenum cofactor". Science. ... November 2011). "Evidence for interstitial carbon in nitrogenase FeMo cofactor". Science. 334 (6058): 940. Bibcode:2011Sci... ...
... nitrogenase, vanadium (V) nitrogenase, and iron-only (Fe) nitrogenase. Molybdenum nitrogenase, which can be found in ... Vanadium nitrogenase and iron-only nitrogenase can both be found in select species of Azotobacter as an alternative nitrogenase ... For example, H2 competes with N2 but not acetylene for nitrogenase (leading to overestimates of nitrogenase by ARA). Bottle or ... No crystallographic analysis has been reported on substrate bound to nitrogenase. Nitrogenase is able to reduce acetylene, but ...
Discuss)   Nitrogenase (EC 1.18.6.1) is the enzyme used by ... Nitrogenase It has been suggested that Dinitrogenase be merged ... Nitrogenase requires both the MoFe protein and ATP, which supplies the energy. Nitrogenase bonds each atom of nitrogen to three ... Nitrogenase is a catalyst for the reaction: N2 + 6H + energy → 2NH3 Since this reaction does not occur very often, and in fact ... Nitrogenase (EC 1.18.6.1) is the enzyme used by some organisms to fix atmospheric nitrogen gas (N2). It is the only known ...
The chemical reactions and pathways resulting in the formation of H2 (dihydrogen) which involve a nitrogenase activity as one ...
alternating mechanism, homocitrate, nitrogen fixation, nitrogenase, QM/MM. in Chemistry - A European Journal. volume. 28. issue ... This may explain why homocitrate is a mandatory component of nitrogenase. All steps in the suggested reaction mechanism are ... This may explain why homocitrate is a mandatory component of nitrogenase. All steps in the suggested reaction mechanism are ... Thermodynamically Favourable States in the Reaction of Nitrogenase without Dissociation of any Sulfide Ligand. *Mark ...
"Nitrogenase" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical Subject ... This graph shows the total number of publications written about "Nitrogenase" by people in this website by year, and whether " ... Below are the most recent publications written about "Nitrogenase" by people in Profiles. ...
... Academic Article * View record in Web of Science ® ...
However, crop inoculation after the green manure intercropping has shown the growth of nitrogenase activity. Used on the ... However, crop inoculation after the green manure intercropping has shown the growth of nitrogenase activity. On mineral ... Under its use the increase of soil nitrogenase activity and low denitrification levels were observed. Same trends were also ... Under its use the increase of soil nitrogenase activity and low denitrification levels were observed. Same trends were also ...
In vitro Synthesis of FeMo-co of Nitrogenase from its basic components molybdenum, iron, sulfur and homocitrate has been ... Die Synthese des Fe-Mo-Cofaktors der Nitrogenase aus seinen Grundkomponenten Molybdän, Eisen, Schwefel und Homocitrat in vitro ... In vitro Biosynthese von komplexen Fe-S-Cluster-Cofaktoren der Fe-Mo-Nitrogenase und der [NiFe]-Hydrogenase. ... Various intermediates along the path of Nitrogenase and Hydrogenase cofactors biosynthesis could be isolated and characterized ...
Rutgers is an equal access/equal opportunity institution. Individuals with disabilities are encouraged to direct suggestions, comments, or complaints concerning any accessibility issues with Rutgers websites to [email protected] or complete the Report Accessibility Barrier / Provide Feedback Form. ...
... researchers at the University of California San Diego report near-atomic-resolution snapshots of nitrogenase during catalysis ... it has been impossible to capture the high-resolution images of nitrogenase, the only enzyme capable of reducing nitrogen into ... Nitrogenase was the essentially the only source of fixed nitrogen in the biosphere until the advent of the Haber-Bosch process- ... Nitrogenase catalysis requires different parts of the enzyme to associate with each other and then come apart several times to ...
Comparative characterization of H2 production by the conventional Mo nitrogenase and the alternative iron only nitrogenase ... "Comparative characterization of H2 production by the conventional Mo nitrogenase and the alternative iron only nitrogenase ... Comparative characterization of H2 production by the conventional Mo nitrogenase and the alternative iron only nitrogenase ... "Comparative characterization of H2 production by the conventional Mo nitrogenase and the alternative iron only nitrogenase ...
Evolution of molybdenum nitrogenase during the transition from anaerobic to aerobic metabolism. In: Journal of bacteriology. ... Boyd, E. S., Garcia Costas, A. M., Hamilton, T. L., Mus, F., & Peters, J. W. (2015). Evolution of molybdenum nitrogenase during ... Evolution of molybdenum nitrogenase during the transition from anaerobic to aerobic metabolism. Journal of bacteriology. 2015; ... Evolution of molybdenum nitrogenase during the transition from anaerobic to aerobic metabolism. / Boyd, Eric S.; Garcia Costas ...
NITROGENASE IRON PROTEIN FROM CLOSTRIDIUM PASTEURIANUM Coordinates. PDB Format Method. X-RAY DIFFRACTION 1.93 Å. Oligo State. ... Schlessman, J.L. et al., Conformational variability in structures of the nitrogenase iron proteins from Azotobacter vinelandii ...
Reports the determination results of nitrogenase activity of induced c... ... It has been demonstrated that the nitrogenase activity in cucumber nudules is at a remarkable level of 99.9%. The nitrogenase ... Determination of Nitrogenase Activity of Induced Cucumber Nodules by 15N Trace Method LI Xinghong1, TIAN Dexiang1, YU Zhongju1 ... Determination of Nitrogenase Activity of Induced Cucumber Nodules by 15N Trace Method[J]. Acta Scientiarum Naturalium ...
Nitrogenase: The Chemistry of Biological Nitrogen Fixation, University of Kentucky Libraries - ExploreUK ... Twentieth Annual Symposium on Chemistry and Molecular Biology: "Nitrogenase: The Chemistry of Biological Nitrogen Fixation". ...
T1 - Genome-wide transcriptional analysis suggests hydrogenase- and nitrogenase-mediated hydrogen production in Clostridium ... title = "Genome-wide transcriptional analysis suggests hydrogenase- and nitrogenase-mediated hydrogen production in Clostridium ... Genome-wide transcriptional analysis suggests hydrogenase- and nitrogenase-mediated hydrogen production in Clostridium ... Genome-wide transcriptional analysis suggests hydrogenase- and nitrogenase-mediated hydrogen production in Clostridium ...
The Nitrogenase Fe- protein was isolated from Rhizobium sps. which was purified and the properties similar to those of the Fe- ...
... nitrogenase. Nitrogenase is a complex and elegantenzyme and though we pretty much know its structure, we haventquite figured ... Haber-Bosch or Nitrogenase?. My husband is a science junkie. The other day he emailed me an articleon Interplanetary ... Nitrogenase exists in symbiotic nitrogen-fixingbacteria that invade the root hairs of host plants, where they multiplyand ... farmers relied on nitrogenase. A Ride on the Interplanetary Superhighway. When we raced to get to the moon, burning vast ...
Biosynthesis of nitrogenase metalloclusters. Ribbe MW, Hu Y, Hodgson KO, Hedman B. Ribbe MW, et al. Among authors: hodgson ko. ... Radical SAM-dependent formation of a nitrogenase cofactor core on NifB. Liu YA, Quechol R, Solomon JB, Lee CC, Ribbe MW, Hu Y, ...
Kato, K., Kanahama, K., & Kanayama, Y. (2010). Involvement of nitric oxide in the inhibition of nitrogenase activity by nitrate ... Kato, K, Kanahama, K & Kanayama, Y 2010, Involvement of nitric oxide in the inhibition of nitrogenase activity by nitrate in ... N2 - Nitrogenase activity, as acetylene-reduction activity (ARA), in Lotus root nodules was clearly inhibited 27 h after the ... AB - Nitrogenase activity, as acetylene-reduction activity (ARA), in Lotus root nodules was clearly inhibited 27 h after the ...
Light-driven dinitrogen reduction catalyzed by a CdS:nitrogenase MoFe protein biohybrid journal, April 2016 * Brown, K. A.; ...
NITROGENASE MOLYBDENUM-IRON PROTEIN FROM CLOSTRIDIUM PASTEURIANUM AT 1.08 A RESOLUTION - 4WES , canSARS ...
Structural Evidence for Nitrogenase Metallocluster Modularity. Trixia Buscagan, Postdoctoral Scholar (Rees Research Group), ...
The V-nitrogenase supports growth as fast as the Mo-nitrogenase on acetate but not on the more oxidized substrate succinate. ... Despite slightly faster growth based on the V-nitrogenase on acetate, the wild-type strain uses exclusively the Mo-nitrogenase ... Notably, the differences in H2:N2 stoichiometry by alternative nitrogenases ( 1.5 for V-nitrogenase, 4-7 for Fe-nitrogenase) ... Our data suggest that this is due to insufficient electron flux to the V-nitrogenase isoform on succinate compared with acetate ...
Hu, Y. and Ribbe, M.W. (2011a). Biosynthesis of nitrogenase Femoco. Coord. Chem. Rev. 255, 1218-1224.10.1016/j.ccr.2010.11.018 ... Hu, Y. and Ribbe, M.W. (2013b). Nitrogenase assembly. Biochim. Biophys. Acta 1827, 1112-1122.10.1016/j.bbabio.2012.12.001Search ... Hu, Y. and Ribbe, M.W. (2013a). Biosynthesis of the iron-molybdenum cofactor of nitrogenase. J. Biol. Chem. 288, 13173-13177. ... AIF4--stabilized nitrogenase complex and its implications for signal transduction. Nature 387, 370-376.10.1038/387370a0Search ...
Alternative nitrogenase activity in the environment and nitrogen cycle implications. Biogeochemistry 127, 189-198 (2016). ... Stüeken, E. E., Buick, R., Guy, B. & Koehler, M. C. Isotopic evidence for biological nitrogen fixation by Mo-nitrogenase from ...
The evolution of the nitrogen-fixing enzyme nitrogenase, which reduces atmospheric N2 to organic NH4. +. , thus represented a ... Isotopic evidence for biological nitrogen fixation by molybdenum-nitrogenase from 3.2 Gyr p.666 Nitrogen is an essential ... most probably using molybdenum-based nitrogenase as opposed to other variants that impart significant negative fractionations. ...
Dance IG, 2010, Mimicking nitrogenase, Journal of the Royal Chemical Society, Dalton Transactions, 39, pp. 2972 - 2983, http ... Dance IG, 2005, The hydrogen chemistry of the FeMo-co active site of nitrogenase, Journal of the American Chemical Society, ... Dance IG, 2011, How does vanadium nitrogenase reduce CO to hydrocarbons?, Journal of the Royal Chemical Society, Dalton ... Dance I, 2023, The HD Reaction of Nitrogenase: a Detailed Mechanism, Chemistry - A European Journal, 29, pp. e202202502, http ...
  • The enzyme nitrogenase, which converts inert molecular nitrogen into biologically active nitrogen, is only found in certain bacteria and is extremely sensitive to oxygen. (upm.es)
  • N 2 fixation is the biogeochemically important conversion of N 2 to ammonium (NH 4 + ) by the enzyme nitrogenase followed by assimilation into biomass. (nature.com)
  • How thermal fluctuations influence the function of the FeMo cofactor in nitrogenase enzymes[J]. Chem Catalysis,2023,3(7). (sustech.edu.cn)
  • Neese, F. Carbon Monoxide Binding to the Iron-Molybdenum Cofactor of Nitrogenase: a Detailed Quantum Mechanics/Molecular Mechanics Investigation. (mpg.de)
  • DeBeer, S. Revisiting the Mössbauer Isomer Shifts of the FeMoco Cluster of Nitrogenase and the Cofactor Charge. (mpg.de)
  • The exact mechanism of catalysis is unknown due to the difficulty in obtaining crystals of nitrogen bound to nitrogenase. (bionity.com)
  • Now, for the first time, researchers at the University of California San Diego report near-atomic-resolution snapshots of nitrogenase during catalysis using cryogenic electron microscopy (cryoEM). (cryogenicsociety.org)
  • Nitrogenase catalysis requires different parts of the enzyme to associate with each other and then come apart several times to make a single ammonia molecule from nitrogen. (cryogenicsociety.org)
  • The implications of our findings on a possible biotechnological H-2 production and on the mechanism of nitrogenase catalysis are considered. (uni-bielefeld.de)
  • A usual assembly consists of two components: The heterotetrameric MoFe protein, a nitrogenase which uses the electrons provided to reduce N2 to NH3. (wikipedia.org)
  • The function of the Fe protein is to transfer electrons from a reducing agent, such as ferredoxin or flavodoxin to the nitrogenase protein. (wikipedia.org)
  • The hydrolysis of ATP also causes a conformational change within the nitrogenase complex, bringing the Fe protein and MoFe protein closer together for easier electron transfer. (wikipedia.org)
  • Nitrogenase requires both the MoFe protein and ATP , which supplies the energy. (bionity.com)
  • Nitrogenase associates with a second protein, and each cycle transfers one electron from an electron donor which is enough to break one of the nitrogen chemical bonds. (bionity.com)
  • Nitrogenase is supplied reducing power when it associates with the reduced, nucleotide-bound homodimeric Fe protein. (bionity.com)
  • The Nitrogenase Fe- protein was isolated from Rhizobium sps. (microbiologyjournal.org)
  • Evidence that MgATP accelerates primary electron transfer in a Clostridium pasteurianum Fe protein- Azotobacter vinelandii MoFe protein nitrogenase tight complex. (degruyter.com)
  • There are three types of nitrogenase found in various nitrogen-fixing bacteria: molybdenum (Mo) nitrogenase, vanadium (V) nitrogenase, and iron-only (Fe) nitrogenase. (wikipedia.org)
  • Molybdenum nitrogenase, which can be found in diazotrophs such as legume-associated rhizobia, is the nitrogenase that has been studied the most extensively and thus is the most well characterized. (wikipedia.org)
  • Equations 1 and 2 show the balanced reactions of nitrogen fixation in molybdenum nitrogenase and vanadium nitrogenase respectively. (wikipedia.org)
  • In vitro Synthesis of FeMo-co of Nitrogenase from its basic components molybdenum, iron, sulfur and homocitrate has been crucial for elucidating the biogenesis of Fe-Mo-Co. During this habilitation, an In vitro Synthesis of active [NiFe]-hydrogenase using only purified components has been elucidated. (uni-halle.de)
  • Molybdenum nitrogenase (Nif), which catalyzes the reduction of dinitrogen to ammonium, has modulated the availability of fixed nitrogen in the biosphere since early in Earth's history. (umn.edu)
  • We discovered that they use the most common enzyme in present-day, molybdenum nitrogenase, to do so. (scitechdaily.com)
  • Now we know that molybdenum nitrogenase works very efficiently, even at low molybdenum concentrations. (scitechdaily.com)
  • Nitrogenase ( EC 1.18.6.1) is the enzyme used by some organisms to fix atmospheric nitrogen gas (N 2 ). (bionity.com)
  • Some enzymes utilize ferredoxin rather than flavodoxin as the electron donor (see EC 1.18.6.1 , nitrogenase). (enzyme-database.org)
  • The critical insights and technological developments in this study not only pave the way for future explorations of the nitrogenase mechanism but enzymes in general," stated Herzik. (cryogenicsociety.org)
  • A key question that drives biological nitrogen-fixation research is the contrast between nitrogenase and the Haber-Bosch process. (cryogenicsociety.org)
  • Biological Nitrogen Fixation ( BNF ) occurs when atmospheric nitrogen is converted to ammonia by a bacterial enzyme called nitrogenase. (newworldencyclopedia.org)
  • We have used combined quantum mechanical and molecular mechanical (QM/MM) calculations to study the reaction mechanism of nitrogenase, assuming that none of the sulfide ligands dissociates. (lu.se)
  • If we can understand the mechanism of nitrogenase, we may not only figure out why nature evolved it to be such a complex enzyme, but we might also uncover design principles for ammonia production in a more cost-effective and environmentally friendly fashion," stated Tezcan. (cryogenicsociety.org)
  • Dance IG , 2015 , 'A Unified Chemical Mechanism for Hydrogenation Reactions Catalyzed by Nitrogenase' , in Weigand W (ed. (edu.au)
  • Dance I , 2019 , 'How feasible is the reversible S-dissociation mechanism for the activation of FeMo-co, the catalytic site of nitrogenase? (edu.au)
  • The catalytic mechanism of N fixation by nitrogenase remains unresolved in how the strong N≡N bond is activated and why the reductive elimination of H is required. (sustech.edu.cn)
  • Here, we use density functional theory and physiologically relevant thermal simulations to elucidate the mechanism of the complete nitrogenase catalytic cycle. (sustech.edu.cn)
  • Vanadium nitrogenase and iron-only nitrogenase can both be found in select species of Azotobacter as an alternative nitrogenase. (wikipedia.org)
  • The Anf nitrogenase in Azotobacter vinelandii is organized in an anfHDGKOR operon. (wikipedia.org)
  • Conformational variability in structures of the nitrogenase iron proteins from Azotobacter vinelandii and Clostridium pasteurianum. (expasy.org)
  • A low-potential terminal oxidase associated with the irononly nitrogenase from the nitrogen-fixing bacterium Azotobacter vinelandii. (mpg.de)
  • It is composed of two components, dinitrogen reductase and dinitrogenase, that can be separated but are both required for nitrogenase activity. (enzyme-database.org)
  • The delta subunits are homologous to each other, and the alpha and beta subunits themselves are homologous to the ones found in MoFe nitrogenase. (wikipedia.org)
  • Previously, it has been impossible to capture the high-resolution images of nitrogenase, the only enzyme capable of reducing nitrogen into ammonia, during catalytic action. (cryogenicsociety.org)
  • These advances led Tezcan and graduate student Hannah Rutledge to consider using cryoEM to study nitrogenase in catalytic action. (cryogenicsociety.org)
  • Various intermediates along the path of Nitrogenase and Hydrogenase cofactors biosynthesis could be isolated and characterized using a multi-disciplinary approach combining biochemical and diverse spectroscopic techniques. (uni-halle.de)
  • Cell suspensions of uptake-hydrogenase-deficient (hup(-)) mutants of a wild-type (B10S) and a nifHDK deletion strain of Rhodobacter capsulatus were used comparatively to characterize the conventional, Mo-containing and the alternative, ''iron-only'' nitrogenase of this organism by determining the H-2 production and acetylene reduction activities under argon and dinitrogen atmospheres. (uni-bielefeld.de)
  • However, most living organisms do not possess the nitrogenase enzyme and cannot metabolize atmospheric nitrogen into a bioprocessable form. (cryogenicsociety.org)
  • Nitrogenase was the essentially the only source of fixed nitrogen in the biosphere until the advent of the Haber-Bosch process-the industrial procedure for converting atmospheric nitrogen to ammonia-more than a hundred years ago. (cryogenicsociety.org)
  • Although much is known about the structure of nitrogenase, until now, no one has been able to acquire atomic-resolution images of the enzyme while "turning over" or in the process of catalyzing atmospheric nitrogen into ammonia, largely due to technological limitations. (cryogenicsociety.org)
  • Nitrogenase, the enzyme which reduces atmospheric nitrogen to biologically useful forms, requires low oxygen concentrations for its existence. (umsystem.edu)
  • The nitrogenase activity in detached nodules of cucumber was also determined by conventional acetylene reduction method. (pku.edu.cn)
  • In both methods clear evidences of nitrogenase activity were obtained for the induced nodules of cucumber. (pku.edu.cn)
  • Nitrogenase activity, as acetylene-reduction activity (ARA), in Lotus root nodules was clearly inhibited 27 h after the addition of nitrate. (elsevierpure.com)
  • These results suggest that NO is involved in the inhibition of nitrogenase activity by nitrate in Lotus root nodules. (elsevierpure.com)
  • Kato, K , Kanahama, K & Kanayama, Y 2010, ' Involvement of nitric oxide in the inhibition of nitrogenase activity by nitrate in Lotus root nodules ', Journal of Plant Physiology , vol. 167, no. 3, pp. 238-241. (elsevierpure.com)
  • In free-living diazotrophs, the nitrogenase-generated ammonium is assimilated into glutamate through the glutamine synthetase/glutamate synthase pathway. (newworldencyclopedia.org)
  • Nitrogenase is able to bind acetylene and carbon monoxide, which are noncompetitive substrates and inhibitors , respectively. (bionity.com)
  • A comparison with the corresponding hup(+) strains revealed that the hup(-) mutation did not affect the nitrogenase activity and specificity within the acetylene-reduction assay, but caused a significant increase in H-2 production, which was more prominent in the case of the Delta nifHDK strain. (uni-bielefeld.de)
  • So the fate of acetylene reveals the presence of nitrogenase, which in turn reveals the presence of nitrogen-fixing bacteria. (scienceblogs.com)
  • During unregulated-pH glucose fermentation increased H2 production was associated with concurrent strong up-regulation of the nitrogenase coding genes. (sckcen.be)
  • The end product of NFIX will be cereal seeds that contain nitrogenase genes and yield productive harvests without any need for nitrogen fertilisation. (upm.es)
  • E. Krahn, K. Schneider, and A. Müller, "Comparative characterization of H2 production by the conventional Mo nitrogenase and the alternative ''iron only'' nitrogenase of Rhodobacter capsulatus hup(-) mutants", APPLIED MICROBIOLOGY AND BIOTECHNOLOGY , vol. 46, 1996, pp. 285-290. (uni-bielefeld.de)
  • Nitrogenase thus breaks the triple bond by getting electron donors for each of the three bonds, and then bonds the nitrogen to hydrogen atoms. (bionity.com)
  • The rhizobia-legume symbioses exhibit variation in symbiotic performance as measured by plant yield, nodulation and nitrogenase activity. (benthamscience.com)
  • Nitrogenase acts as a catalyst, reducing this energy barrier such that the reaction can take place at ambient temperatures. (wikipedia.org)
  • His group developed a combined biochemical-genetic approach to identify where substrates interact with nitrogenase, the biological catalyst of nitrogen fixation. (asbmb.org)
  • Nitrogenase is an enzyme responsible for catalyzing nitrogen fixation, which is the reduction of nitrogen (N2) to ammonia (NH3) and a process vital to sustaining life on Earth. (wikipedia.org)
  • Since this reaction does not occur very often, and in fact goes the other way more easily, with ammonia breaking down into nitrogen and hydrogen, without nitrogenase, there would be much less life than presently exists. (bionity.com)
  • Nitrogenase bonds each atom of nitrogen to three atoms of hydrogen to form ammonia or NH 3 , and then ammonia is bonded to glutamate and becomes glutamine . (bionity.com)
  • The chemical reactions and pathways resulting in the formation of H2 (dihydrogen) which involve a nitrogenase activity as one of the steps. (mcw.edu)
  • Under its use the increase of soil nitrogenase activity and low denitrification levels were observed. (frontiersin.org)
  • However, crop inoculation after the green manure intercropping has shown the growth of nitrogenase activity. (frontiersin.org)
  • The involvement of NO production in the inhibition of nitrogenase activity by nitrate was investigated using the NO donor sodium nitroprusside (SNP) and the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO). (elsevierpure.com)
  • Increased transcript accumulation is associated with two events, the first is nodule organogenesis, while the second is induction of nitrogenase activity. (usda.gov)
  • Especially legumes like Glycine max or Medicago truncatula have an increased numbers of MOT1-family members for supplying their symbionts with molybdate for nitrogenase activity. (bvsalud.org)
  • This may explain why homocitrate is a mandatory component of nitrogenase. (lu.se)
  • To be able to obtain atomic-level-resolution pictures of an enzyme as dynamic and complex as nitrogenase in action is extremely exciting. (cryogenicsociety.org)
  • Although scientists can obtain atomic-resolution images of proteins using X-ray crystallography, this method requires the proteins to be fixed in place within a crystal-stationary in a sense-which means that it cannot capture nitrogenase in action. (cryogenicsociety.org)
  • The invention describes a biotechnological method for making highly oxygen-sensitive proteins, such as nitrogenase, functional in eukaryotic cells (fungi, plants and animals). (upm.es)
  • And that's exactly what happened - the test showed that nitrogenase was present and active in the gardens of all the 8 leafcutter species that Pinto-Tomas analysed. (scienceblogs.com)
  • Dance I , 2018 , 'What is the role of the isolated small water pool near FeMo-co, the active site of nitrogenase? (edu.au)
  • Production of active nitrogenase in eukaryotic cells. (upm.es)
  • The expression of nitrogenase in the mitochondrial matrix overcomes the main difficulty in producing nitrogen-fixing cereals: the presence of molecular oxygen derived from photosynthesis. (upm.es)
  • NFIX uses the mitochondrion as a key organelle for storing nitrogenase, since this is where cellular respiration takes place and oxygen levels are very low. (upm.es)
  • The conversion of N 2 to NH 4 + is energetically costly and requires high nitrogenase levels 10 . (nature.com)
  • The Azotobacteraceae are unique in their ability to employ an oxygen-labile nitrogenase under aerobic conditions. (bionity.com)
  • When these conditions were applied, the BIOS strain only expressed the Mo nitrogenase. (uni-bielefeld.de)
  • This graph shows the total number of publications written about "Nitrogenase" by people in this website by year, and whether "Nitrogenase" was a major or minor topic of these publications. (rush.edu)
  • Below are the most recent publications written about "Nitrogenase" by people in Profiles. (rush.edu)
  • The overall results suggest, for the first time, that environmental factors may determine whether H2 production in C. butyricum CWBI 1009 is mediated by the hydrogenases and/or the nitrogenase. (sckcen.be)