A Baeyer-Villiger monooxygenase from Cupriavidus basilensis catalyzes asymmetric synthesis of (R)-lansoprazole and other pharmaco-sulfoxides.

Biocatalytic synthesis of pharmaco-chiral sulfoxides has gained interest in recent years for its environmental friendliness. However, only a few natural biocatalysts can be used for the efficient synthesis of pharmaco-sulfoxides, including (R)-lansoprazole, a chiral proton pump inhibitor used to treat gastrointestinal diseases. In this study, the sequence of BoBVMO (Baeyer-Villiger monooxygenase from Bradyrhizobium oligotrophicum) was used as a probe to identify BVMOs via genomic mining for the highly efficient synthesis of (R)-lansoprazole and other pharmaco-sulfoxides. After virtual sequence filtering, target gene cloning, heterologous expression, and activity screening for lansoprazole sulfide (LPS) monooxygenation, seven new BVMOs were identified among more than 10,000 homologous BVMOs. According to the conserved sequence and phylogenetic tree analysis, these discovered enzymes belong to the family of type I BVMOs and the ethionamide monooxygenase subtype. Among them, CbBVMO, Baeyer-Villiger monooxygenase from Cupriavidus basilensis, showed the highest efficiency and excellent enantioselectivity for converting LPS into (R)-lansoprazole. Moreover, CbBVMO showed a wide substrate spectrum toward other bulky prazole-family sulfides. The results indicate that CbBVMO is a potential enzyme for extending the application of BVMOs in pharmaceutical industry. KEY POINTS: • CbBVMO is the most efficient biocatalyst for (R)-lansoprazole biosynthesis. • CbBVMO catalyzes the conversion of various bulky prazole sulfides. • CbBVMO is a promising enzyme for the biosynthesis of pharmaco-sulfoxides.