Part of the acuABC operon, which is possibly involved in the breakdown of acetoin and butanediol. Acts as an acetyltransferase inactivating acetyl-CoA synthetase AcsA via acetylation at a Lys residue. Ketone degradation; acetoin degradation. Monomer. Induced by glucose starvation conditions. No visible phenotype on growth in medium containing glucose and acetoin or in medium with acetate compared to wild-type. After glucose exhaustion acetoin is quickly consumed similarly to wild-type. In the late exponential growth phase slightly more pyruvate is produced compared to wild-type. Belongs to the acetyltransferase family.