A phylum of ARCHAEA comprising at least seven classes: Methanobacteria, Methanococci, Halobacteria (extreme halophiles), Archaeoglobi (sulfate-reducing species), Methanopyri, and the thermophiles: Thermoplasmata, and Thermococci.
A kingdom in the domain ARCHAEA comprised of thermoacidophilic, sulfur-dependent organisms. The two orders are SULFOLOBALES and THERMOPROTEALES.
Deoxyribonucleic acid that makes up the genetic material of archaea.
One of the three domains of life (the others being BACTERIA and Eukarya), formerly called Archaebacteria under the taxon Bacteria, but now considered separate and distinct. They are characterized by: (1) the presence of characteristic tRNAs and ribosomal RNAs; (2) the absence of peptidoglycan cell walls; (3) the presence of ether-linked lipids built from branched-chain subunits; and (4) their occurrence in unusual habitats. While archaea resemble bacteria in morphology and genomic organization, they resemble eukarya in their method of genomic replication. The domain contains at least four kingdoms: CRENARCHAEOTA; EURYARCHAEOTA; NANOARCHAEOTA; and KORARCHAEOTA.
The functional genetic units of ARCHAEA.
An order of aerobic, thermophilic archaea, in the kingdom EURYARCHAEOTA, characterized by the absence of a cell wall. Two genera have been described: THERMOPLASMA and Picrophilus.
The genetic complement of an archaeal organism (ARCHAEA) as represented in its DNA.
Ribonucleic acid in archaea having regulatory and catalytic roles as well as involvement in protein synthesis.
A kingdom of hyperthermophilic ARCHAEA found in diverse environments.
The relationships of groups of organisms as reflected by their genetic makeup.
Proteins found in any species of archaeon.
A genus of strictly anaerobic ultrathermophilic archaea, in the family THERMOCOCCACEAE, occurring in heated seawaters. They exhibit heterotrophic growth at an optimum temperature of 100 degrees C.
The salinated water of OCEANS AND SEAS that provides habitat for marine organisms.
The simplest saturated hydrocarbon. It is a colorless, flammable gas, slightly soluble in water. It is one of the chief constituents of natural gas and is formed in the decomposition of organic matter. (Grant & Hackh's Chemical Dictionary, 5th ed)
Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.
A genus of extremely thermophilic heterotrophic archaea, in the family THERMOCOCCACEAE, occurring in heated sea flows. They are anaerobic chemoorganotropic sulfidogens.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)
A genus of aerobic, chemolithotrophic, coccoid ARCHAEA whose organisms are thermoacidophilic. Its cells are highly irregular in shape, often lobed, but occasionally spherical. It has worldwide distribution with organisms isolated from hot acidic soils and water. Sulfur is used as an energy source.
The variety of all native living organisms and their various forms and interrelationships.
DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.
A collective genome representative of the many organisms, primarily microorganisms, existing in a community.
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.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.
A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)
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.
The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.
Genes, found in both prokaryotes and eukaryotes, which are transcribed to produce the RNA which is incorporated into RIBOSOMES. Prokaryotic rRNA genes are usually found in OPERONS dispersed throughout the GENOME, whereas eukaryotic rRNA genes are clustered, multicistronic transcriptional units.
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.