A single active site mutation inverts stereoselectivity of 16-hydroxylation of testosterone catalyzed by engineered cytochrome P450 BM3.

Department of Chemistry and Pharmaceutical Sciences, Division of Molecular and Computational Toxicology, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, Netherlands.
ChemBioChem (Impact Factor: 3.74). 03/2012; 13(4):520-3. DOI: 10.1002/cbic.201100750
Source: PubMed

ABSTRACT Inversion of stereoselectivity: screening of a minimal mutant library revealed a cytochrome P450 BM3 variant M01 A82W S72I capable of producing 16 α-OH-testosterone. Remarkably, a single active site mutation S72I in M01 A82W inverted the stereoselectivity of hydroxylation from 16 β to 16 α. Introduction of S72I mutation in another 16 β-OH-selective variant M11 V87I, also resulted in similar inversion of stereoselectivity.

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