| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 70095 | Journal of Molecular Catalysis B: Enzymatic | 2013 | 6 Pages |
With the aim to enlarge the set of available flavoprotein monooxygenases, we have cloned 8 unexplored genes from Rhodococcus jostii RHA1 that were predicted to encode class B flavoprotein monooxygenases. Each monooxygenase can be expressed as soluble protein and has been tested for conversion of sulfides and ketones. Not only enantioselective sulfoxidations, but also enantioselective Baeyer–Villiger oxidations could be performed with this set of monooxygenases. Interestingly, in contrast to known class B flavoprotein monooxygenases, all studied biocatalysts showed no nicotinamide coenzyme preference. This feature coincides with the fact that the respective sequences appear to form a discrete group of sequence related proteins, distinct from the known class B flavoprotein monooxygenases subclasses: the so-called flavin-containing monooxygenases (FMOs), N-hydroxylating monooxygenases (NMOs) and Type I Baeyer–Villiger monooxygenases (BVMOs). Taken together, these data reveal the existence of a new subclass of class B flavoprotein monooxygenases, which we coined as Type II FMOs, that can perform Baeyer–Villiger oxidations and accept both NADPH and NADH as coenzyme. The uncovered biocatalytic properties of the studied Type II FMOs make this newly recognized subclass of monooxygenases of potential interest for biocatalytic applications.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► 8 newly identified flavoprotein monooxygenases were produced in recombinant form. ► Several of the discovered monooxygenases were shown to catalyze enantioselective sulfoxidations and Baeyer–Villiger oxidations. ► Sequence and biocatalytic analyses have revealed a new sequence-related group of flavoprotein monooxygenases that can catalyze Baeyer–Villiger oxidations and sulfoxidation and that show no coenzyme preference.
