Cloning and Application of a New Acylaminoacyl Peptidase from Bacillus subtilis 168 for Aldol Reaction

Abstract

Acylaminoacyl peptidase has been named acyl-peptide releasing enzyme( AARE),catalyses the removal of an N-acylated amino acid from N-α-acylpeptides. In this research,a novel acyl-peptide releasing enzyme gene( BSU32230) from Bacillus subtilis 168 was cloned and expressed in Escherichia coli BLP DE3 codon plus to produce acyl-peptide releasing enzyme. The recombinant enzyme was purified in two steps:ammonium sulfate precipitation and Ni2+-column affinity chromatography. The optimum temperature and p H of enzyme were 50 ℃ and 8. 0,respectively. The half-life of recombinant enzyme at 40 ℃ was 29 h,the enzyme was stable at p H range from 4 to 10. This report demonstrated the acylaminoacyl peptidase from Bacillus subtilis peptidase can catalyze aldol reaction and showed high enantioselectivity. The reaction provided optically active secondary alcohol with satisfying enantioselectivity( 84. 6% e.e.).