Acetate kinase is a key enzyme for many methanogenic bacteria as it is able to catalyse the interconversion of acetate and acetyl phosphate using the removal of a phosphate from ATP. Structural analysis of the enzyme from Methanosarcina thermophila, an Archaea, shows that it is a member of the sugar kinase superfamily which includes hexokinase, and geochemical studies suggest that it is most likely to be the urkinase- the ancestor of all of the members of the superfamily.
Defined by 5 residues: ASN:A-7ARG:A-91HIS:A-180ARG:A-241GLU:A-384