Microbial production of D-amino acids

The production of D-aminoacylase by Alcaligenes denitrificans and Alcaligen es faecalis has been studied. The enzyme was inducibly produced and N-acety l-D-leucine and N-acetyl-D-valine were the most effective inducers. D-methi onine, D-valine, D-phenylalamine and D-leucine were produced by the enzymic hydrolysis of the appropriate N-acetyl-D-amino-acids with whole cell bioma ss. The hydrolysis of N-acetyl-D-methionine by A. denitrificans and N-acety l-D-valine by A. faecalis was preferential. Maximum yields of D-methionine and D-valine were 94.3 and 84.7% at a specific product formation rate of 20 .10 and 19.19 mu mol min(-1) mg(-1) of wet cells at 20 mM substrate concent ration and 5 mg ml(-1) of cell density. (C) 2000 Elsevier Science Ltd. Ail rights reserved.