- Source: Methanogenium frigidum
Methanogenium frigidum is a psychrophilic, H2-using methanogen from Ace Lake, Antarctica.
Description and metabolism
Cells are psychrophilic, irregular, slightly halophilic and non-motile coccoids (diameter 1.2 to 2.5 μm). They require salt to grow. They prefer low temperatures: their optimal temperature is 15 °C, and they cannot grow at 18 °C–20 °C. They reduce carbon dioxide with hydrogen to produce methane, but it may be possible that they use other substrates as well. One experiment showed that these cells grow best in the presence of yeast extract.
Genome
The genome of this species differs from those of archaea that prefer higher temperatures. It contains more polar amino acids, particularly Gln and Thr, and fewer non-polar ones, particularly Leu. Unlike hyperthermophiles, in psychrophiles, the GC content is the most important factor to the stability of the tRNA.
References
Further reading
Saunders, N. F.W. (2003). "Mechanisms of Thermal Adaptation Revealed From the Genomes of the Antarctic Archaea Methanogenium frigidum and Methanococcoides burtonii". Genome Research. 13 (7): 1580–1588. doi:10.1101/gr.1180903. ISSN 1088-9051. PMC 403754. PMID 12805271.
Falkow, Stanley; Dworkin, Martin (2006). The prokaryotes: a handbook on the biology of bacteria. Berlin: Springer. ISBN 0-387-25493-5.
Garrett, Roger A., and Hans-Peter Klenk, eds. Archaea: evolution, physiology, and molecular biology. Wiley. com, 2008.
External links
"Methanogenium frigidum". The Encyclopedia of Life.
LPSN
Type strain of Methanogenium frigidum at BacDive - the Bacterial Diversity Metadatabase