The members of this family are described as 3-ketoacyl-CoA synthases, type III polyketide synthases, fatty acid elongases and fatty acid condensing enzymes, and are found in both prokaryotic and eukaryotic (mainly plant) species. The region featured in this family contains the active site residues, as well as motifs involved in substrate binding [1].

1: Alteration of reaction and substrate specificity of a bacterial type III polyketide synthase by site-directed mutagenesis. Funa N, Ohnishi Y, Ebizuka Y, Horinouchi S; Biochem J 2002;367:781-789. PMID:12139488