Stereoselective enzymatic synthesis of an aspartame precursor of N-CBZ-l-Asp-l-PheOMe

A stereoselective protease produced by Bacillus amyloliquefaciens KCCM 12091 was isolated. The enzyme catalyzed the synthesis of N-CBZ-l-Asp-PheOMe from N-CBZ-l-Asp and l-PheOMe, but not N-CBZ-l-Asp-d-PheOMe from N-CBZ-l-Asp and d-PheOMe. More than 50% of added l-PheOMe was consumed when eutectic mixtures of N-CBZ-l-Asp, racemic l- and d-PheOMe were used for synthesis of an aspartame precursor of N-CBZ-l-Asp-l-PheOMe. d-PheOMe was not involved in the reaction and did not affect synthesis of N-CBZ-l-Asp-l-PheOMe.