Engineering the meso-diaminopimelate dehydrogenase from Symbiobacterium thermophilum by site saturation mutagenesis for D-phenylalanine synthesis.
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ABSTRACT:
SUBMITTER: Gao X
PROVIDER: S-EPMC3754726 | biostudies-literature | 2013 Aug
REPOSITORIES: biostudies-literature
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Engineering the meso-diaminopimelate dehydrogenase from Symbiobacterium thermophilum by site saturation mutagenesis for D-phenylalanine synthesis.
Gao Xiuzhen X Huang Fang F Feng Jinhui J Chen Xi X Zhang Hailing H Wang Zhixiang Z Wu Qiaqing Q Zhu Dunming D
Applied and environmental microbiology 20130531 16
In order to enlarge the substrate binding pocket of the meso-diaminopimelate dehydrogenase from Symbiobacterium thermophilum to accommodate larger 2-keto acids, four amino acid residues (Phe146, Thr171, Arg181, and His227) were targeted for site saturation mutagenesis. Among all mutants, the single mutant H227V had a specific activity of 2.39 ± 0.06 U · mg(-1), which was 35.1-fold enhancement over the wild-type enzyme. ...[more]
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