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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Cyclization of a cellular dipentaenone by Streptomyces coelicolor cytochrome P450 154A1 without oxidation/reduction
Qian Cheng1, David C Lamb, Steven L Kelly
1Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University, School of Medicine, Nashville Tennessee 37232-0146, USA.
Abstract:
We report a comprehensive genetic, metabolomic, and biochemical study on the catalytic properties of Streptomyces coelicolor cytochrome P450 (P450) 154A1, known to have a unique heme orientation in its crystal structure. Deletion of the P450 154A1 gene compromised the long-term stability of the bacterial spores. A novel dipentaenone (1) with a high degree of conjugation was identified as an endogenous substrate of P450 154A1 using a metabolomics approach. The biotransformation of 1 by P450 154A1 was shown to be an unexpected intramolecular cyclization to a Paternò-Büchi-like product, without oxidation/reduction.
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