Enantioselective synthesis of pure (R,R)-2,3-butanediol in Escherichia coli with stereospecific secondary alcohol dehydrogenases

We characterized the activity and stereospecificity of four secondary alcohol dehydrogenases (sADHs) towards acetoin reduction and constructed synthetic pathways in E. coli to produce enantiomerically pure (R,R)-2,3-butanediol (2,3-BDO) from glucose with a titer of 6.1 g/L (enantio purity >99%), and yield of 0.31 g product/g glucose (62% of theoretical maximum).