InterPro: IPR011904 Acetate--CoA ligase

Acetyl-CoA synthetase (also known as acetate-CoA ligase and acetyl-activating enzyme) is a ubiquitous enzyme, found in both prokaryotes and eukaryotes, which catalyses the formation of acetyl-CoA from acetate, coenzyme A (CoA) and ATP as shown below [1]:

ATP + acetate + CoA = AMP + diphosphate + acetyl-CoA

The crystal structures of a eukaryotic (Q01574, from yeast) and bacterial (Q8ZKF6, from Salmonella) form of this enzyme have been determined [2, 3]. The yeast enzyme is trimeric, while the bacterial enzyme is monomeric. The trimeric state of the yeast protein may be unique to this organism however, as the residues involved in the trimer interface are poorly conserved in other sequences. Despite differences in the oligomeric state of the two enzyme, the structures of the monomers are almost identical. A large N-terminal domain (~500 residues) containing two parallel beta sheets is followed by a small (~110 residues) C-terminal domain containing a three-stranded beta sheet with helices. The active site occurs at the domain interface, with its contents determining the orientation of the C-terminal domain.