WcxM-like, Left-handed parallel beta-Helix (LbH) N-terminal domain: This group is composed of Xanthomonas campestris WcxM and proteins with similarity to the WcxM N-terminal domain. WcxM is thought to be bifunctional, catalyzing both the isomerization and transacetylation reactions of keto-hexoses. It contains an N-terminal LbH domain responsible for the transacetylation function and a C-terminal isomerase domain. The LbH domain contains imperfect tandem repeats of a hexapeptide repeat motif (X-[STAV]-X-[LIV]-[GAED]-X), typical of enzymes with acyltransferase activity.
Comment:Based on the structures of E. coli galactoside acetyltransferase and Enterococcus faecium streptogramin acetyltransferase Vat(D) bound to CoA and their respective substrates.
Comment:Active acetyltransferases in this family are trimeric, with active sites located at the interface between two LbH subunits. The trimer structure contains three active sites and each subunit contributes to two active sites via residues located on two surfaces.