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Artificial imine reductase mutant S112A-N118P-K121A-S122MArtificial imine reductase mutant S112A-N118P-K121A-S122M
Structural highlights
Function[SAV_STRAV] The biological function of streptavidin is not known. Forms a strong non-covalent specific complex with biotin (one molecule of biotin per subunit of streptavidin). Publication Abstract from PubMedArtificial metalloenzymes, resulting from incorporation of a metal cofactor within a host protein, have received increasing attention in the last decade. Herein, we report on the directed evolution of an Artificial Transfer Hydrogenase (ATHase) based on the biotin-streptavidin technology using a straightforward optimized protocol allowing screening in cell free extracts. Our efforts yielded two streptavidin isoforms with improved catalytic activity and selectivity for the reduction of cyclic imines. Gratifyingly, the evolved ATHases proved stable under biphasic catalytic conditions. The X-ray structure analysis reveals that introducing bulky residues within the active site results in flexibility changes of the cofactor, thus increasing exposure of the metal to the protein surface and leading to a reversal of enantioselectivity. This hypothesis was confirmed by a multiscale approach based mostly on molecular dynamics and protein-ligand dockings. Directed Evolution of Artificial Imine Reductase.,Hestericova M, Heinisch T, Alonso-Cotchico L, Marechal JD, Vidossich P, Ward TR Angew Chem Int Ed Engl. 2017 Dec 19. doi: 10.1002/anie.201711016. PMID:29265726[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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