Uncovering the cytochrome P450-catalyzed methylenedioxy bridge formation in streptovaricins biosynthesis
| Autor: | Chaoqun Hu, Zixin Deng, Yuanzhen Liu, Xu Chen, Zhengyuan Li, Qing Mei, Guo Sun, Yuhui Sun, Minghe Luo, Zhengyu Zhang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0301 basic medicine
Stereochemistry Science General Physics and Astronomy Streptovaricin Crystallography X-Ray Methylation 01 natural sciences General Biochemistry Genetics and Molecular Biology Methylenedioxy Article Hydroxylation 03 medical and health sciences chemistry.chemical_compound Bacterial Proteins Cytochrome P-450 Enzyme System Catalytic triad Nucleophilic substitution Moiety lcsh:Science Heme Enzyme Assays X-ray crystallography Multidisciplinary 010405 organic chemistry Ansamycin Mutagenesis Acetylation General Chemistry Recombinant Proteins Streptomyces 0104 chemical sciences 030104 developmental biology chemistry Enzyme mechanisms Biocatalysis Mutagenesis Site-Directed lcsh:Q Natural product synthesis Oxidoreductases |
| Zdroj: | Nature Communications, Vol 11, Iss 1, Pp 1-12 (2020) Nature Communications |
| ISSN: | 2041-1723 |
| Popis: | Streptovaricin C is a naphthalenic ansamycin antibiotic structurally similar to rifamycins with potential anti-MRSA bioactivities. However, the formation mechanism of the most fascinating and bioactivity-related methylenedioxy bridge (MDB) moiety in streptovaricins is unclear. Based on genetic and biochemical evidences, we herein clarify that the P450 enzyme StvP2 catalyzes the MDB formation in streptovaricins, with an atypical substrate inhibition kinetics. Furthermore, X-ray crystal structures in complex with substrate and structure-based mutagenesis reveal the intrinsic details of the enzymatic reaction. The mechanism of MDB formation is proposed to be an intramolecular nucleophilic substitution resulting from the hydroxylation by the heme core and the keto-enol tautomerization via a crucial catalytic triad (Asp89-His92-Arg72) in StvP2. In addition, in vitro reconstitution uncovers that C6-O-methylation and C4-O-acetylation of streptovaricins are necessary prerequisites for the MDB formation. This work provides insight for the MDB formation and adds evidence in support of the functional versatility of P450 enzymes. Streptovaricin C is an antibiotic containing a methylenedioxy bridge (MDB) moiety essential for its activity. Here, the authors show that a P450 monooxygenase StvP2 catalyses MDB formation, report its crystal structure in complex with the substrate, and elucidate mechanistic details of MDB formation. |
| Databáze: | OpenAIRE |
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