National Engineering Laboratory for Industrial Enzymes and Tianjin Engineering Center for Biocatalytic Technology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
Appl Environ Microbiol. 2013 Aug;79(16):5078-81. doi: 10.1128/AEM.01049-13. Epub 2013 May 31.
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.
为了扩大嗜热栖热菌中中间二氨基庚二酸脱氢酶的基质结合口袋，以容纳更大的 2-酮酸，针对四个氨基酸残基（F146、T171、R181 和 H227）进行了定点饱和突变。在所有突变体中，单突变体 H227V 的比活为 2.39 ± 0.06 U·mg(-1)，比野生型酶提高了 35.1 倍。
