Cloning and characterization of a novel beta-transaminase from Mesorhizobium sp. strain LUK: a new biocatalyst for the synthesis of enantiomerically pure beta-amino acids.

ABSTRACT: A novel beta-transaminase gene was cloned from Mesorhizobium sp. strain LUK. By using N-terminal sequence and an internal protein sequence, a digoxigenin-labeled probe was made for nonradioactive hybridization, and a 2.5-kb gene fragment was obtained by colony hybridization of a cosmid library. Through Southern blotting and sequence analysis of the selected cosmid clone, the structural gene of the enzyme (1,335 bp) was identified, which encodes a protein of 47,244 Da with a theoretical pI of 6.2. The deduced amino acid sequence of the beta-transaminase showed the highest sequence similarity with glutamate-1-semialdehyde aminomutase of transaminase subgroup II. The beta-transaminase showed higher activities toward d-beta-aminocarboxylic acids such as 3-aminobutyric acid, 3-amino-5-methylhex

SUBMITTER: Kim J 

PROVIDER: S-EPMC1828820 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature