What Factors Determine the Brevione B Desaturation Mechanism in the Nonheme Iron Dioxygenase BrvJ?

作者：Jingyu Cao, Jiakai Lu, Yuanxin Cao, Sam P. de Visser · 发表于：Chemistry - A European Journal · 年份：2025 · DOI：10.1002/chem.202404250 · 被引用次数：9 · 研究领域：Metal-Catalyzed Oxygenation Mechanisms、Photosynthetic Processes and Mechanisms、Enzyme-mediated dye degradation

Abstract The natural product synthesis of brevione J undergoes a cascade of reactions including an oxidative desaturation and a ring‐expansion. The C 1 −C 2 desaturation of brevione B is catalyzed by the nonheme iron dioxygenase BrvJ using one molecule of O 2 and α‐ketoglutarate (αKG). However, whether the subsequent oxidative ring expansion reaction is also catalyzed by the same enzyme is unknown and remains controversial. To gain insight into the mechanism of brevione J biosynthesis a computational study is reported here using molecular dynamics and density functional theory approaches. The work predicts that both cycles can proceed in the same protein structure on an iron center with O 2 and αKG for each cycle. The rate‐determining step is a hydrogen atom abstraction step in both reaction cycles. Interestingly, the OH rebound barriers are high in energy in cycle 1 due to stereochemical interactions and substrate positioning that enable an efficient desaturation reaction.