Room-temperature X-ray data collection enabled the structural determination of statin-bound CYP105A1

Streptomyces griseolus CYP105A1 exhibits monooxygenase activity towards a wide variety of structurally diverse substrates with regiospecificity and stereospecificity, making it suitable for broad applications. Our previous studies have demonstrated that both wild-type CYP105A1 and its mutants metabolize vitamin D₃ and its derivatives, as well as 12 types of nonsteroidal anti-inflammatory drugs (NSAIDs) and statins. Notably, the R84A mutant displayed high activity against vitamin D₃, numerous NSAIDs and statins. Although we were unable to obtain CYP105A1-statin complex structures through co-crystallization and standard cryo data collection, we successfully acquired complex structures with mevastatin and simvastatin using room-temperature data collection with a conventional capillary method. We observed that the reduced unit-cell dimensions of the cryo crystals resulted in increased symmetry interactions, which induced cis-trans conversion of the peptide bond between Pro142 and Thr143 and conformational changes in the residues critical for statin binding. It is suggested that these increased symmetry interactions in the cryo crystals lead to dissociation of the statins from the active site of the enzyme.