Enhanced acetoin production by Serratia marcescens H32 with expression of a water-forming NADH oxidase

▸ NADH oxidase was expressed to regulate NAD+ and NADH concentrations. ▸ Expression of NADH oxidase could be self-induced employing the pPbud-nox plasmid. ▸ Acetoin production was remarkably enhanced while 2,3-butanediol was decreased. ▸ Production and productivity of acetoin were new records on acetoin fermentation.