title: Biosynthesis of a steroid metabolite by an engineered Rhodococcus erythropolis strain expressing a mutant cytochrome P450 BM3 enzyme.
abstract: In the present study, the use of Rhodococcus erythropolis mutant strain RG9 expressing the cytochrome P450 BM3 mutant M02 enzyme has been evaluated for whole-cell biotransformation of a 17-ketosteroid, norandrostenedione, as a model substrate. Purified P450 BM3 mutant M02 enzyme hydroxylated the steroid with >95 % regioselectivity to form 16-β-OH norandrostenedione, as confirmed by NMR analysis. Whole cells of R. erythropolis RG9 expressing P450 BM3 M02 enzyme also converted norandrostenedione into the 16-β-hydroxylated product, resulting in the formation of about 0.35 g/L. Whole cells of strain RG9 itself did not convert norandrostenedione, indicating that metabolite formation is P450 BM3 M02 enzyme mediated. This study shows that R. erythropolis is a novel and interesting host for the heterologous expression of highly selective and active P450 BM3 M02 enzyme variants able to perform steroid bioconversions.
authors.affiliation: AIMMS-Division of Molecular Toxicology, Department of Chemistry and Pharmaceutical Sciences, Vrije Universiteit, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands.
authors.forename: Harini
authors.initials: H
authors.lastname: Venkataraman
authors.forename: Evelien M
authors.initials: EM
authors.lastname: Te Poele
authors.forename: Kamila Z
authors.initials: KZ
authors.lastname: Rosłoniec
authors.forename: Nico
authors.initials: N
authors.lastname: Vermeulen
authors.forename: Jan N M
authors.initials: JN
authors.lastname: Commandeur
authors.forename: Robert
authors.initials: R
authors.lastname: van der Geize
authors.forename: Lubbert
authors.initials: L
authors.lastname: Dijkhuizen
mesh_terms: D001711:Biotransformation; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000378:metabolism*; D006900:Hydroxylation; D009682:Magnetic Resonance Spectroscopy; D060847:Metabolic Engineering; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D009635:Norandrostanes / Q000378:metabolism*; D012240:Rhodococcus / Q000235:genetics* / Q000378:metabolism*
chemical_list: D050505:Mutant Proteins; D009635:Norandrostanes; D003577:Cytochrome P-450 Enzyme System