InterPro domain: IPR011278

Members of this family are dimeric enzymes with activity as 2-methylcitrate synthase, citrate synthase, or both. Many Gram-negative species have a hexameric citrate synthase, termed citrate synthase I. Members of this family appear as a second citrate synthase isozyme, but typically are associated with propionate metabolism and synthesise 2-methylcitrate from propionyl-CoA; citrate synthase activity may be incidental [ 1 ]. A number of species, including Thermoplasma acidophilum, Pyrococcus furiosus, and the Antarctic bacterium DS2-3R have a bifunctional member of this family as the only citrate synthase isozyme.

1. Citrate synthase and 2-methylcitrate synthase: structural, functional and evolutionary relationships. Microbiology (Reading, Engl.) 144 ( Pt 4), 929-35