<p>A single member of this protein family is found in each of the first ten complete genome sequences of archaeal methanogens, and nowhere else. Sequence similarity to various bacterial proteins is reflected in <db_xref db="INTERPRO" dbkey="IPR000728"/> and <db_xref db="INTERPRO" dbkey="IPR010918"/>, AIR synthase related protein N-terminal and C-terminal domains, respectively. The functions of proteins in this family are unknown, but their role is likely one essential to methanogenesis.</p> Putative methanogenesis marker protein 2