화학공학소재연구정보센터
Applied Microbiology and Biotechnology, Vol.99, No.20, 8495-8514, 2015
Comparison of CYP106A1 and CYP106A2 from Bacillus megaterium-identification of a novel 11-oxidase activity
The CYP106A subfamily hydroxylates steroids, diterpenes, and triterpenes in a regioselective and stereoselective manner, which is a challenging task for synthetic chemistry. The well-studied CYP106A2 enzyme, from the Bacillus megaterium strain ATCC 13368, is a highly promising candidate for the pharmaceutical industry. It shares 63 % amino acid sequence identity with CYP106A1 from B. megaterium DSM319, which was recently characterized. A focused steroid library was screened with both CYP106A1 and CYP106A2. Out of the 23 tested steroids, 19 were successfully converted by both enzymes during in vitro and in vivo reactions. Thirteen new substrates were identified for CYP106A1, while the substrate spectrum of CYP106A2 was extended by seven new members. Finally, six chosen steroids were further studied on a preparative scale employing a recombinant B. megaterium MS941 whole-cell system, yielding sufficient amounts of product for structure characterization by nuclear magnetic resonance. The hydroxylase activity was confirmed at positons 6 beta, 7 beta, 9 alpha, and 15 beta. In addition, the CYP106A subfamily showed unprecedented 11-oxidase activity, converting 11 beta-hydroxysteroids to their 11-keto derivatives. This novel reaction and the diverse hydroxylation positions on pharmaceutically relevant compounds underline the role of the CYP106A subfamily in drug development and production.