Thermoplasma | |
---|---|
Scientific classification ![]() | |
Domain: | Archaea |
Phylum: | Methanobacteriota |
Class: | Thermoplasmata |
Order: | Thermoplasmatales |
Family: | Thermoplasmataceae |
Genus: | Thermoplasma Darland et al. 1970 |
Type species | |
Thermoplasma acidophilum Darland et al. 1970 | |
Species | |
|
Thermoplasma is a genus of archaeans. [1] It belongs to the class Thermoplasmata, which thrive in acidic and high-temperature environments. Thermoplasma are facultative anaerobes and respire using sulfur and organic carbon. They do not contain a cell wall but instead contain a unique membrane composed mainly of a tetraether lipoglycan containing atypical archaeal tetraether lipid attached to a glucose- and mannose-containing oligosaccharide. This lipoglycan is presumably responsible for the acid and thermal stability of the Thermoplasma membrane.
Nanoarchaeota is a proposed phylum in the domain Archaea that currently has only one representative, Nanoarchaeum equitans, which was discovered in a submarine hydrothermal vent and first described in 2002.
Euryarchaeota is a kingdom of archaea. Euryarchaeota are highly diverse and include methanogens, which produce methane and are often found in intestines; halobacteria, which survive extreme concentrations of salt; and some extremely thermophilic aerobes and anaerobes, which generally live at temperatures between 41 and 122 °C. They are separated from the other archaeans based mainly on rRNA sequences and their unique DNA polymerase. The only validly published name for this group under the Prokaryotic Code is Methanobacteriati.
A hyperthermophile is an organism that thrives in extremely hot environments—from 60 °C (140 °F) upwards. An optimal temperature for the existence of hyperthermophiles is often above 80 °C (176 °F). Hyperthermophiles are often within the domain Archaea, although some bacteria are also able to tolerate extreme temperatures. Some of these bacteria are able to live at temperatures greater than 100 °C, deep in the ocean where high pressures increase the boiling point of water. Many hyperthermophiles are also able to withstand other environmental extremes, such as high acidity or high radiation levels. Hyperthermophiles are a subset of extremophiles. Their existence may support the possibility of extraterrestrial life, showing that life can thrive in environmental extremes.
The mevalonate pathway, also known as the isoprenoid pathway or HMG-CoA reductase pathway is an essential metabolic pathway present in eukaryotes, archaea, and some bacteria. The pathway produces two five-carbon building blocks called isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), which are used to make isoprenoids, a diverse class of over 30,000 biomolecules such as cholesterol, vitamin K, coenzyme Q10, and all steroid hormones.
Sulfolobus is a genus of microorganism in the family Sulfolobaceae. It belongs to the archaea domain.
A thermoacidophile is an extremophilic microorganism that is both thermophilic and acidophilic; i.e., it can grow under conditions of high temperature and low pH. The large majority of thermoacidophiles are archaea or bacteria, though occasional eukaryotic examples have been reported. Thermoacidophiles can be found in hot springs and solfataric environments, within deep sea vents, or in other environments of geothermal activity. They also occur in polluted environments, such as in acid mine drainage.
In taxonomy, Picrophilus is an archaean genus of the family Picrophilaceae.
Acidilobales are an order of archaea in the class Thermoprotei.
Archaea is a domain of organisms. Traditionally, Archaea only included its prokaryotic members, but this sense has been found to be paraphyletic, as eukaryotes are now known to have evolved from archaea. Even though the domain Archaea includes eukaryotes, the term "archaea" in English still generally refers specifically to prokaryotic members of Archaea. Archaea were initially classified as bacteria, receiving the name archaebacteria, but this term has fallen out of use.
The outflow of acidic liquids and other pollutants from mines is often catalysed by acid-loving microorganisms; these are the acidophiles in acid mine drainage.
The Nitrososphaerota are a phylum of the Archaea proposed in 2008 after the genome of Cenarchaeum symbiosum was sequenced and found to differ significantly from other members of the hyperthermophilic phylum Thermoproteota. Three described species in addition to C. symbiosum are Nitrosopumilus maritimus, Nitrososphaera viennensis, and Nitrososphaera gargensis. The phylum was proposed in 2008 based on phylogenetic data, such as the sequences of these organisms' ribosomal RNA genes, and the presence of a form of type I topoisomerase that was previously thought to be unique to the eukaryotes. This assignment was confirmed by further analysis published in 2010 that examined the genomes of the ammonia-oxidizing archaea Nitrosopumilus maritimus and Nitrososphaera gargensis, concluding that these species form a distinct lineage that includes Cenarchaeum symbiosum. The lipid crenarchaeol has been found only in Nitrososphaerota, making it a potential biomarker for the phylum. Most organisms of this lineage thus far identified are chemolithoautotrophic ammonia-oxidizers and may play important roles in biogeochemical cycles, such as the nitrogen cycle and the carbon cycle. Metagenomic sequencing indicates that they constitute ~1% of the sea surface metagenome across many sites.
Glycerate 2-kinase is an enzyme with systematic name ATP:D-glycerate 2-phosphotransferase. This enzyme catalyses the following chemical reaction
Thermoplasma acidophilum is an archaeon, the type species of its genus. T. acidophilum was originally isolated from a self-heating coal refuse pile, at pH 2 and 59 °C. Its genome has been sequenced.
Thermoplasma volcanium is a moderate thermoacidophilic archaea isolated from acidic hydrothermal vents and solfatara fields. It contains no cell wall and is motile. It is a facultative anaerobic chemoorganoheterotroph. No previous phylogenetic classifications have been made for this organism. Thermoplasma volcanium reproduces asexually via binary fission and is nonpathogenic.
Sulfolobus metallicus is a coccoid shaped thermophilic archaeon. It is a strict chemolithoautotroph gaining energy by oxidation of sulphur and sulphidic ores into sulfuric acid. Its type strain is Kra 23. It has many uses that take advantage of its ability to grow on metal media under acidic and hot environments.
Methanococcus maripaludis is a species of methanogenic archaea found in marine environments, predominantly salt marshes. M. maripaludis is a non-pathogenic, gram-negative, weakly motile, non-spore-forming, and strictly anaerobic mesophile. It is classified as a chemolithoautotroph. This archaeon has a pleomorphic coccoid-rod shape of 1.2 by 1.6 μm, in average size, and has many unique metabolic processes that aid in survival. M. maripaludis also has a sequenced genome consisting of around 1.7 Mbp with over 1,700 identified protein-coding genes. In ideal conditions, M. maripaludis grows quickly and can double every two hours.
Picrophilus oshimae is a species of Archaea described in 1996. Picrophilus oshimae was found in a fumarole in Hokkaido, Japan. The hot spring the fumarole was located in had a pH of 2.2.
Acidilobus saccharovorans is a thermoacidophilic species of anaerobic archaea. The species was originally described in 2009 after being isolated from hot springs in Kamchatka.
"Candidatus Aciduliprofundum boonei" is an obligate thermoacidophilic candidate species of archaea belonging to the phylum "Euryarchaeota". Isolated from acidic hydrothermal vent environments, "Ca. A. boonei" is the first cultured representative of a biogeochemically significant clade of thermoacidophilic archaea known as the "Deep-Sea Hydrothermal Vent Euryarchaeota 2 (DHVE2)".