Acyl Coenzyme A
S-Acyl coenzyme A. Fatty acid coenzyme A derivatives that are involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation.
Coenzyme A
Sterol O-Acyltransferase
An enzyme that catalyzes the formation of cholesterol esters by the direct transfer of the fatty acid group from a fatty acyl CoA derivative. This enzyme has been found in the adrenal gland, gonads, liver, intestinal mucosa, and aorta of many mammalian species. EC 2.3.1.26.
Coenzymes
Small molecules that are required for the catalytic function of ENZYMES. Many VITAMINS are coenzymes.
Acyltransferases
Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.
Diacylglycerol O-Acyltransferase
Retinol O-Fatty-Acyltransferase
An enzyme that catalyzes the acyl group transfer of acyl COENZYME A to RETINOL to generate COENZYME A and a retinyl ester.
Palmitoyl Coenzyme A
Acyl-CoA Dehydrogenase
A flavoprotein oxidoreductase that has specificity for medium-chain fatty acids. It forms a complex with ELECTRON TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.
Diazepam Binding Inhibitor
An 86-amino acid polypeptide, found in central and peripheral tissues, that displaces diazepam from the benzodiazepine recognition site on the gamma-aminobutyric acid receptor (RECEPTORS, GABA). It also binds medium- and long-chain acyl-CoA esters and serves as an acyl-CoA transporter. This peptide regulates lipid metabolism.
Acyl-CoA Oxidase
An enzyme that catalyzes the first and rate-determining steps of peroxisomal beta-oxidation of fatty acids. It acts on COENZYME A derivatives of fatty acids with chain lengths from 8 to 18, using FLAVIN-ADENINE DINUCLEOTIDE as a cofactor.
Waxes
A plastic substance deposited by insects or obtained from plants. Waxes are esters of various fatty acids with higher, usually monohydric alcohols. The wax of pharmacy is principally yellow wax (beeswax), the material of which honeycomb is made. It consists chiefly of cerotic acid and myricin and is used in making ointments, cerates, etc. (Dorland, 27th ed)
Fatty Acids
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
Ricinoleic Acids
Eighteen carbon fatty acids that comprise the great majority of CASTOR OIL, which is from the seed of RICINUS.
Ubiquinone
Mycobacteriaceae
Acetyl Coenzyme A
Acetyl CoA participates in the biosynthesis of fatty acids and sterols, in the oxidation of fatty acids and in the metabolism of many amino acids. It also acts as a biological acetylating agent.
Hydroxymethylglutaryl CoA Reductases
Enzymes that catalyze the reversible reduction of alpha-carboxyl group of 3-hydroxy-3-methylglutaryl-coenzyme A to yield MEVALONIC ACID.
Multiple Acyl Coenzyme A Dehydrogenase Deficiency
An autosomal recessive disorder of fatty acid oxidation, and branched chain amino acids (AMINO ACIDS, BRANCHED-CHAIN); LYSINE; and CHOLINE catabolism, that is due to defects in either subunit of ELECTRON TRANSFER FLAVOPROTEIN or its dehydrogenase, electron transfer flavoprotein-ubiquinone oxidoreductase (EC 1.5.5.1).
Fatty Acid Desaturases
Palmitoyl-CoA Hydrolase
Enzyme catalyzing reversibly the hydrolysis of palmitoyl-CoA or other long-chain acyl coenzyme A compounds to yield CoA and palmitate or other acyl esters. The enzyme is involved in the esterification of fatty acids to form triglycerides. EC 3.1.2.2.
Carbon-Carbon Ligases
Triazenes
Substrate Specificity
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Acyl-CoA Dehydrogenases
Enzymes that catalyze the first step in the beta-oxidation of FATTY ACIDS.
Heterocyclic Compounds, 1-Ring
Cholesterol Esters
Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis.
Sterol Esterase
An enzyme that catalyzes the hydrolysis of CHOLESTEROL ESTERS and some other sterol esters, to liberate cholesterol plus a fatty acid anion.
Oxidoreductases
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)
Caprylates
Derivatives of caprylic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a carboxy terminated eight carbon aliphatic structure.
Glycerol-3-Phosphate O-Acyltransferase
An enzyme that transfers acyl groups from acyl-CoA to glycerol-3-phosphate to form monoglyceride phosphates. It acts only with CoA derivatives of fatty acids of chain length above C-10. Also forms diglyceride phosphates. EC 2.3.1.15.
Cholesterol
Esters
Amino Acid Sequence
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Coenzyme A-Transferases
Enzymes which transfer coenzyme A moieties from acyl- or acetyl-CoA to various carboxylic acceptors forming a thiol ester. Enzymes in this group are instrumental in ketone body metabolism and utilization of acetoacetate in mitochondria. EC 2.8.3.
Esterification
The process of converting an acid into an alkyl or aryl derivative. Most frequently the process consists of the reaction of an acid with an alcohol in the presence of a trace of mineral acid as catalyst or the reaction of an acyl chloride with an alcohol. Esterification can also be accomplished by enzymatic processes.
Cobamides
Oleic Acids
A group of fatty acids that contain 18 carbon atoms and a double bond at the omega 9 carbon.
Carboxylic Ester Hydrolases
Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.
Escherichia coli
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Liver
Mesna
Oleic Acid
Cloning, Molecular
Microsomes, Liver
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Pantothenic Acid
A butyryl-beta-alanine that can also be viewed as pantoic acid complexed with BETA ALANINE. It is incorporated into COENZYME A and protects cells against peroxidative damage by increasing the level of GLUTATHIONE.
Microbodies
Pantetheine
Lipid Metabolism
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
Base Sequence
Oxidation-Reduction
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).
Sequence Homology, Amino Acid
NAD
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
Gene Expression Regulation, Enzymologic
Triglycerides
Mutation
Euryarchaeota
Propanediol Dehydratase
Malonyl Coenzyme A
A coenzyme A derivative which plays a key role in the fatty acid synthesis in the cytoplasmic and microsomal systems.
NADP
Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)
Acetate-CoA Ligase
An enzyme that catalyzes the formation of CoA derivatives from ATP, acetate, and CoA to form AMP, pyrophosphate, and acetyl CoA. It acts also on propionates and acrylates. EC 6.2.1.1.
Sequence Analysis, DNA
Methanosarcina barkeri
Alcohol Oxidoreductases
A subclass of enzymes which includes all dehydrogenases acting on primary and secondary alcohols as well as hemiacetals. They are further classified according to the acceptor which can be NAD+ or NADP+ (subclass 1.1.1), cytochrome (1.1.2), oxygen (1.1.3), quinone (1.1.5), or another acceptor (1.1.99).
Mevalonic Acid
Mevalonic acid is a crucial intermediate compound in the HMG-CoA reductase pathway, which is a metabolic route that produces cholesterol, other steroids, and isoprenoids in cells.
Hydroxymethylglutaryl-CoA Reductase Inhibitors
Compounds that inhibit HMG-CoA reductases. They have been shown to directly lower cholesterol synthesis.
Riboflavin
Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.
Methanobacterium
A genus of anaerobic, rod-shaped METHANOBACTERIACEAE. Its organisms are nonmotile and use ammonia as the sole source of nitrogen. These methanogens are found in aquatic sediments, soil, sewage, and the gastrointestinal tract of animals.
Lovastatin
A fungal metabolite isolated from cultures of Aspergillus terreus. The compound is a potent anticholesteremic agent. It inhibits 3-hydroxy-3-methylglutaryl coenzyme A reductase (HYDROXYMETHYLGLUTARYL COA REDUCTASES), which is the rate-limiting enzyme in cholesterol biosynthesis. It also stimulates the production of low-density lipoprotein receptors in the liver.
Phosphatidylcholines
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.
Macrophages
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Acetates
Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.
Molecular Structure
Binding Sites
Phospholipids
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Catalysis
Cells, Cultured
Pyridoxal Phosphate
This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).
Hydroxymethylglutaryl-CoA-Reductases, NADP-dependent
Specific hydroxymethylglutaryl CoA reductases that utilize the cofactor NAD. In liver enzymes of this class are involved in cholesterol biosynthesis.
Methylmalonyl-CoA Mutase
Magnetic Resonance Spectroscopy
Methane
Structure-Activity Relationship
Models, Molecular
Hydrogen-Ion Concentration
Oxo-Acid-Lyases
Simvastatin
A derivative of LOVASTATIN and potent competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HYDROXYMETHYLGLUTARYL COA REDUCTASES), which is the rate-limiting enzyme in cholesterol biosynthesis. It may also interfere with steroid hormone production. Due to the induction of hepatic LDL RECEPTORS, it increases breakdown of LDL CHOLESTEROL.
Chromatography, High Pressure Liquid
Vitamin B 12
A cobalt-containing coordination compound produced by intestinal micro-organisms and found also in soil and water. Higher plants do not concentrate vitamin B 12 from the soil and so are a poor source of the substance as compared with animal tissues. INTRINSIC FACTOR is important for the assimilation of vitamin B 12.
Phosphate Acetyltransferase
Acetyltransferases
Enzymes catalyzing the transfer of an acetyl group, usually from acetyl coenzyme A, to another compound. EC 2.3.1.
Fatty Acid Synthase, Type II
The form of fatty acid synthase complex found in BACTERIA; FUNGI; and PLANTS. Catalytic steps are like the animal form but the protein structure is different with dissociated enzymes encoded by separate genes. It is a target of some ANTI-INFECTIVE AGENTS which result in disruption of the CELL MEMBRANE and CELL WALL.
Sterols
Flavin-Adenine Dinucleotide
A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)
Thiolester Hydrolases
Thiolester hydrolases are enzymes that catalyze the hydrolysis of thioester bonds, commonly found in acetyl-CoA and other coenzyme A derivatives, to produce free carboxylic acids and CoASH.
Chromatography, Thin Layer
Glutamate Dehydrogenase
Fatty Acid Synthases
Enzymes that catalyze the synthesis of FATTY ACIDS from acetyl-CoA and malonyl-CoA derivatives.
Acyl-Carrier Protein S-Malonyltransferase
This enzyme catalyzes the transacylation of malonate from MALONYL CoA to activated holo-ACP, to generate malonyl-(acyl-carrier protein), which is an elongation substrate in FATTY ACIDS biosynthesis. It is an essential enzyme in the biosynthesis of FATTY ACIDS in all BACTERIA.
Mercaptoethanol
Protein Binding
Methanosarcina
A genus of anaerobic, irregular spheroid-shaped METHANOSARCINALES whose organisms are nonmotile. Endospores are not formed. These archaea derive energy via formation of methane from acetate, methanol, mono-, di-, and trimethylamine, and possibly, carbon monoxide. Organisms are isolated from freshwater and marine environments.
Hydroxymethylglutaryl-CoA Synthase
Phosphatidylethanolamines
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to an ethanolamine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and ethanolamine and 2 moles of fatty acids.
Methyltransferases
3-Oxoacyl-(Acyl-Carrier-Protein) Synthase
Ethanolamine Ammonia-Lyase
Apoenzymes
Membrane Lipids
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
Models, Chemical
Temperature
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Protein Conformation
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Palmitic Acids
A group of 16-carbon fatty acids that contain no double bonds.
Alcohol Dehydrogenase
A zinc-containing enzyme which oxidizes primary and secondary alcohols or hemiacetals in the presence of NAD. In alcoholic fermentation, it catalyzes the final step of reducing an aldehyde to an alcohol in the presence of NADH and hydrogen.
Lipid Bilayers
Carnitine
A constituent of STRIATED MUSCLE and LIVER. It is an amino acid derivative and an essential cofactor for fatty acid metabolism.
Spectrophotometry, Ultraviolet
Glutarates
Glutarates are organic compounds, specifically carboxylic acids, that contain a five-carbon chain with two terminal carboxyl groups and a central methyl group, playing a role in various metabolic processes, including the breakdown of certain amino acids. They can also refer to their salts or esters. Please note that this definition is concise and may not cover all aspects of glutarates in depth.
Crystallography, X-Ray
Lipids
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
Calorimetry, Differential Scanning
Clostridium
Succinate-CoA Ligases
Enzymes that catalyze the first step leading to the oxidation of succinic acid by the reversible formation of succinyl-CoA from succinate and CoA with the concomitant cleavage of ATP to ADP (EC 6.2.1.5) or GTP to GDP (EC 6.2.1.4) and orthophosphate. Itaconate can act instead of succinate and ITP instead of GTP.EC 6.2.1.-.
Malonates
Fatty Acids, Unsaturated
Acetyl-CoA C-Acetyltransferase
An enzyme that catalyzes the formation of acetoacetyl-CoA from two molecules of ACETYL COA. Some enzymes called thiolase or thiolase-I have referred to this activity or to the activity of ACETYL-COA C-ACYLTRANSFERASE.
Stereoisomerism
Carboxy-Lyases
Propionates
Derivatives of propionic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxyethane structure.
Mitochondria
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
Propylene Glycol
Xanthobacter
A genus of gram-negative, aerobic, rod-shaped bacteria found in wet soil containing decaying organic material and in water. Cells tend to be pleomorphic if grown on media containing succinate or coccoid if grown in the presence of an alcohol as the sole carbon source. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
Acetyl-CoA Carboxylase
Methanobacteriaceae
Spectrophotometry
Multienzyme Complexes
Systems of enzymes which function sequentially by catalyzing consecutive reactions linked by common metabolic intermediates. They may involve simply a transfer of water molecules or hydrogen atoms and may be associated with large supramolecular structures such as MITOCHONDRIA or RIBOSOMES.
Mass Spectrometry
Flavin Mononucleotide
A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues.
Chemistry
Acetyl-CoA C-Acyltransferase
Chemical Phenomena
Lipid A
Intramolecular Transferases
Hydro-Lyases
Succinates
Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure.
Parabens
Methyl, propyl, butyl, and ethyl esters of p-hydroxybenzoic acid. They have been approved by the FDA as antimicrobial agents for foods and pharmaceuticals. (From Hawley's Condensed Chemical Dictionary, 11th ed, p872)
Methanol
A colorless, flammable liquid used in the manufacture of FORMALDEHYDE and ACETIC ACID, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness.
Dimethylamines
Polyketide Synthases
Large enzyme complexes composed of a number of component enzymes that are found in STREPTOMYCES which biosynthesize MACROLIDES and other polyketides.
Streptomyces
Sequence Alignment
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Sphingomyelins
A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.
Enzyme Stability
Adenosine Triphosphate
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.