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. Activity is sensitive to salt concentration, a high concentration of KCL (500 mM) is needed for complete inactivation. Optimum pH is 7.5. Optimum temperature 37 degrees Celsius. Thermostable. Retains 93, 78 and 15 % of its protein acetyltransferase activity after heating to 100 degrees Celsius for 5, 30 and 60 minutes, respectively. Ketone degradation; acetoin degradation. Monomer. Expression is maximal in stationary phase and is repressed by the addition of glucose to the growth medium. CcpA protein is required for glucose repression. Acetoin does not act as an inducer. Up-regulated during the 80 to 100 minutes of spore germination and into the outgrowth phase. Does not impair growth on acetate. Disruption together with other acetoin utilization genes acuB and acuC results in poor growth and sporulation on acetoin or butanediol. Triple deletion of acuA, acuC and srtN improves the growth on acetate but it does not reach that of wild-type under low-acetate conditions. Belongs to the acetyltransferase family.