Jinjin Xu1, Yajun Bai2, Taiping Fan2,3, Xiaohui Zheng2, Yujie Cai4. 1. The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China. 2. College of Life Sciences, Northwest University, Xi'an, 710069, Shanxi, China. 3. Department of Pharmacology, University of Cambridge, Cambridge, CB2 1T, UK. 4. The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China. yjcai@jiangnan.edu.cn.
Abstract
OBJECTIVES: To characterize a novel membrane-bound D -amino acid dehydrogenase from Proteus mirabilis JN458 (PmDAD). RESULTS: The recombinant PmDAD protein, encoding a peptide of 434 amino acids with a MW of 47.7 kDa, exhibited broad substrate specificity with D -alanine the most preferred substrate. The K m and V max values for D -alanine were 9 mM and 20 μmol min-1 mg-1, respectively. Optimal activity was at pH 8 and 45 °C. Additionally, this PmDAD generated H2O2 and exhibited 68 and 60% similarity with E. coli K12 DAD and Pseudomonas aeruginosa DAD, respectively, with low degrees of sequence similarity with other bacterial DADs. CONCLUSIONS: D-Amino acid dehydrogenase from Proteus mirabilis JN458 was expressed and characterized for the first time, DAD was confirmed to be an alanine dehydrogenase.
OBJECTIVES: To characterize a novel membrane-bound D -amino acid dehydrogenase from Proteus mirabilis JN458 (PmDAD). RESULTS: The recombinant PmDAD protein, encoding a peptide of 434 amino acids with a MW of 47.7 kDa, exhibited broad substrate specificity with D -alanine the most preferred substrate. The K m and V max values for D -alanine were 9 mM and 20 μmol min-1 mg-1, respectively. Optimal activity was at pH 8 and 45 °C. Additionally, this PmDAD generated H2O2 and exhibited 68 and 60% similarity with E. coli K12 DAD and Pseudomonas aeruginosa DAD, respectively, with low degrees of sequence similarity with other bacterial DADs. CONCLUSIONS: D-Amino acid dehydrogenase from Proteus mirabilis JN458 was expressed and characterized for the first time, DAD was confirmed to be an alanine dehydrogenase.
Entities:
Keywords:
Characterization; D -amino acid; D -amino acid dehydrogenase; Proteus mirabilis