Molecular insights into the endoperoxide formation by Fe(II)/ alpha-KG-dependent oxygenase NvfI.
Mori, T., Zhai, R., Ushimaru, R., Matsuda, Y., Abe, I.(2021) Nat Commun 12: 4417-4417
- PubMed: 34285212 
- DOI: https://doi.org/10.1038/s41467-021-24685-6
- Primary Citation of Related Structures:  
7DE2, 7EMZ, 7ENB - PubMed Abstract: 
Endoperoxide-containing natural products are a group of compounds with structurally unique cyclized peroxide moieties. Although numerous endoperoxide-containing compounds have been isolated, the biosynthesis of the endoperoxides remains unclear. NvfI from Aspergillus novofumigatus IBT 16806 is an endoperoxidase that catalyzes the formation of fumigatonoid A in the biosynthesis of novofumigatonin. Here, we describe our structural and functional analyses of NvfI. The structural elucidation and mutagenesis studies indicate that NvfI does not utilize a tyrosyl radical in the reaction, in contrast to other characterized endoperoxidases. Further, the crystallographic analysis reveals significant conformational changes of two loops upon substrate binding, which suggests a dynamic movement of active site during the catalytic cycle. As a result, NvfI installs three oxygen atoms onto a substrate in a single enzyme turnover. Based on these results, we propose a mechanism for the NvfI-catalyzed, unique endoperoxide formation reaction to produce fumigatonoid A.
Organizational Affiliation: 
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan. tmori@mol.f.u-tokyo.ac.jp.