taxonomy Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

, the Methanosarcinales are an order of the

Methanomicrobia In the taxonomy of microorganisms, the Methanomicrobia are a class of the Euryarchaeota. Phylogeny The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature List of Prokaryotic names with Stand ...

. Large amounts of methane are produced in

marine sediments Marine sediment, or ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated on the seafloor. These particles have their origins in soil and rocks and have been transported from the land to the sea, mainly ...

but are then consumed before contacting aerobic waters or the atmosphere. Although no organism that can consume methane anaerobically has ever been isolated, biogeochemical evidence indicates that the overall process involves a transfer of electrons from methane to sulphate and is probably mediated by several organisms, including a

methanogen Methanogens are microorganisms that produce methane as a metabolic byproduct in hypoxic conditions. They are prokaryotic and belong to the domain Archaea. All known methanogens are members of the archaeal phylum Euryarchaeota. Methanogens are com ...

(operating in reverse) and a sulfate-reducer (using an unknown intermediate substrate). Organisms placed within the order can be found in freshwater, saltwater, salt-rich sediments, laboratory digestors, and animal digestive systems. Most cells have cell walls that lack

peptidoglycan Peptidoglycan or murein is a unique large macromolecule, a polysaccharide, consisting of sugars and amino acids that forms a mesh-like peptidoglycan layer outside the plasma membrane, the rigid cell wall (murein sacculus) characteristic of most ...

and

pseudomurein Pseudopeptidoglycan (also known as pseudomurein;White, David. (1995) ''The Physiology and Biochemistry of Prokaryotes'', pages 6, 12-21. (Oxford: Oxford University Press). . PPG hereafter) is a major cell wall component of some Archaea that differs ...

. They are strictly anaerobic and survive by producing

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Eart ...

. Some species use

acetate An acetate is a salt (chemistry), salt formed by the combination of acetic acid with a base (e.g. Alkali metal, alkaline, Alkaline earth metal, earthy, Transition metal, metallic, nonmetallic or radical Radical (chemistry), base). "Acetate" als ...

as a substrate and others use methyl compounds, such as methyl amines and methyl sulfates.

Phylogeny

References

External links

Archaea taxonomic orders Euryarchaeota {{Euryarchaeota-stub

Phylogeny

See also

References

Further reading

Scientific journals

Scientific books

Scientific databases

External links