Euryarchaeota
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.
Crenarchaeota
A kingdom in the domain ARCHAEA comprised of thermoacidophilic, sulfur-dependent organisms. The two orders are SULFOLOBALES and THERMOPROTEALES.
DNA, Archaeal
Deoxyribonucleic acid that makes up the genetic material of archaea.
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.
Genes, Archaeal
The functional genetic units of ARCHAEA.
Thermoplasmales
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.
Genome, Archaeal
The genetic complement of an archaeal organism (ARCHAEA) as represented in its DNA.
RNA, Archaeal
Ribonucleic acid in archaea having regulatory and catalytic roles as well as involvement in protein synthesis.
Nanoarchaeota
A kingdom of hyperthermophilic ARCHAEA found in diverse environments.
Pyrococcus
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.
Methane
RNA, Ribosomal, 16S
Thermococcus
A genus of extremely thermophilic heterotrophic archaea, in the family THERMOCOCCACEAE, occurring in heated sea flows. They are anaerobic chemoorganotropic sulfidogens.
Bacteria
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.
Geologic Sediments
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)
Sulfolobus
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.
Biodiversity
DNA, Ribosomal
Metagenome
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.
Sequence Analysis, DNA
Water Microbiology
The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.
Ecosystem
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.
Evolution, Molecular
Soil Microbiology
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.