Inversion of enantioselectivity of serine proteases

Article abstract of DOI:10.1002/recl.19951140421

The enantioselectivity of serine proteases in the transesterification of N-acetyl-(D,L)-phenylalanine esters with propan-1-ol in cyclohexane is strongly influenced by the leaving ability of the alcoholate group.Moreover the enantioselectivity is greatly influenced by the addition of small amounts (0.33 M) of organic additives.Addenda with a small molecular volume like e.g. ethanol and acetonitrile increase the rate for the L-enantiomer whereas alcohols with bulky alkyl groups like e.g. tert-butanol and 2-methylbutan-2-ol enhance the activity of the enzyme towards the D-enantiomer.This enables a rational tuning of the enantioselectivity as was demonstrated for four different proteases (α-chymotrypsin, subtilisin Carlsberg, Aspergillus oryzae protease, and elastase).