Methanosarcinales is an
order of
Archaea
Archaea ( ) is a Domain (biology), domain of organisms. Traditionally, Archaea only included its Prokaryote, prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even thou ...
in the class ''
Methanomicrobia'', phylum ''
Methanobacteriota''. The order ''Methanosarcinales'' contains both
methanogen
Methanogens are anaerobic archaea that produce methane as a byproduct of their energy metabolism, i.e., catabolism. Methane production, or methanogenesis, is the only biochemical pathway for Adenosine triphosphate, ATP generation in methanogens. A ...
ic and
methanotrophic lineages, although the latter have so far no pure culture representatives. Methanotrophic lineages of the order ''Methanosarcinales'' were initially abbreviated as ANME (anaerobic
methanotrophs) to distinguich from aerobic methanotrophic bacteria. Currently, those lineages receive their own names such as Ca. Methanoperedens, Ca. Methanocomedens (ANME-2a), Ca.Methanomarinus (ANME-2b), Ca. Methanogaster (ANME-2c), Ca. Methanovorans (ANME-3). The order contains archaeon with one of the largest genome, ''
Methanosarcina acetivorans'' C2A, genome size 5,75 Mbp.
The organisms placed within the order can be found in freshwater, saltwater, salt-rich sediments, anaerobic digestors, and animal digestive systems. The order consist of mesophiles or moderately thermophillic, neutrophilic or alkaliphilic species with some able to grow at high salt concentrations (genera ''Methanohalobium'' , ''Methanohalophilus'' , and ''Methanosalsum''). Most of the species in the order were isolated or detected in marine and freshawater sediments, soil with only a few specialized lineages adapted to the digestive tract of animals - genera ''
Methanimicrococcus'', ''Methanolapillus'', and ''Ca''. Methanofrustulum that can be found in termites/cockroaches, millipedes, and ruminants, respectively.
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 layer (sacculus) that surrounds the bacterial cytoplasmic membrane. The sugar component consists of alternating ...
and
pseudomurein with notable presence of methanochondroitin in ''Methanosarcina'' genus. As all other methanogens, ''Methanosarcinales'' representatives are strictly anaerobic and utilize
methanogenesis pathway as the only path for
ATP production. However, besides common among other methanogens substrates H
2/CO
2, Methanosarcinales characterized by the ability to utilize acetate (aceticlastic methanogenesis), methylated compounds such as methanol or methnylamines (methylotrophic methanogenesis), or even methoxyalted aromatic compounds (methoxydotrophic methanogenesis).
Phylogeny
The order ''Methanosarcinales'' contains the following families (genera comprising each family listed below corresponding family):
Methanosarcinaceae Balch and Wolfe 1981
* ''Methanimicrococcus'' corrig. Sprenger ''et al.'' 2000
* ''Methanococcoides'' Sowers and Ferry 1985
* ''Methanohalobium'' Zhilina and Zavarzin 1988
* ''Methanohalophilus'' Paterek and Smith 1988
* ''Methanolobus'' König and Stetter 1983
* ''Methanomethylovorans'' Lomans ''et al.'' 2004
* ''Methanosalsum'' Boone and Baker 2002
* ''Methanosarcina'' Kluyver and van Niel 1936
Methanotrichaceae Akinyemi ''et al.'' 2021
* ''Methanothrix'' Huser ''et al.'' 1983
Methermicoccaceae Cheng ''et al.'' 2007
* ''Methermicoccus'' Cheng ''et al.'' 2007
See also
*
List of Archaea genera
This article lists the genera of the Archaea. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). However, in the List provided bel ...
References
Further reading
Scientific journals
*
*
Scientific books
*
*
*
Version 5.0
External links
Archaea taxonomic orders
Euryarchaeota
Long stubs with short prose
{{Euryarchaeota-stub