Download MendeleyCharacterization of the Pro101Gln mutation that enhances the catalytic performance of T. indicus NADH-dependent d-lactate dehydrogenase.
Liu, J., Liu, G., Han, X., Tao, F., Xu, P.(2023) Structure 31: 1616-1628.e3
- PubMed: 37729918
- DOI: https://doi.org/10.1016/j.str.2023.08.019
- Primary Citation of Related Structures:
8I5Z - PubMed Abstract:
NADH-dependent d-lactate dehydrogenases (d-LDH) are important for the industrial production of d-lactic acid. Here, we identify and characterize an improved d-lactate dehydrogenase mutant (d-LDH1) that contains the Pro101Gln mutation. The specific enzyme activities of d-LDH1 toward pyruvate and NADH are 21.8- and 11.0-fold greater compared to the wild-type enzyme. We determined the crystal structure of Apo-d-LDH1 at 2.65 Å resolution. Based on our structural analysis and docking studies, we explain the differences in activity with an altered binding conformation of NADH in d-LDH1. The role of the conserved residue Pro101 in d-LDH was further probed in site-directed mutagenesis experiments. We introduced d-LDH1 into Bacillus licheniformis yielding a d-lactic acid production of 145.9 g L -1 within 60 h at 50°C, which was three times higher than that of the wild-type enzyme. The discovery of d-LDH1 will pave the way for the efficient production of d-lactic acid by thermophilic bacteria.
Organizational Affiliation:
State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
