Download MendeleyStructure-guided engineering of ChKRED20 from Chryseobacterium sp. CA49 for asymmetric reduction of aryl ketoesters.
Li, T.B., Zhao, F.J., Liu, Z., Jin, Y., Liu, Y., Pei, X.Q., Zhang, Z.G., Wang, G., Wu, Z.L.(2019) Enzyme Microb Technol 125: 29-36
- PubMed: 30885322
- DOI: https://doi.org/10.1016/j.enzmictec.2019.03.001
- Primary Citation of Related Structures:
6IXM - PubMed Abstract:
ChKRED20 is a robust NADH-dependent ketoreductase identified from the genome of Chryseobacterium sp. CA49 that can use 2-propanol as the ultimate reducing agent. The wild-type can reduce over 100 g/l ketones for some pharmaceutical relevant substrates, exhibiting a remarkable potential for industrial application. In this work, to overcome the limitation of ChKRED20 to aryl ketoesters, we first refined the X-ray crystal structure of ChKRED20/NAD + complex at a resolution of 1.6 Å, and then performed three rounds of iterative saturation mutagenesis at critical amino acid sites to reshape the active cavity of the enzyme. For methyl 2-oxo-2-phenylacetate and ethyl 3-oxo-3-phenylpropanoate, several gain-of-activity mutants were achieved, and for ethyl 2-oxo-4-phenylbutanoate, improved mutants were achieved with k cat /K m increasing to 196-fold of the wild-type. All three substrates were completely reduced at 100 g/l loading catalyzed with selected ChKRED20 mutants, and deliver the corresponding chiral alcohols with >90% isolated yield and 97 - >99%ee.
Organizational Affiliation:
Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu, 610041, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
