9BU9

Mixed-valent (2/3) dimanganese SfbO

9BU9 の概要

• エントリーDOI: 10.2210/pdb9bu9/pdb
• 分子名称: Amidohydrolase family protein, GLYCEROL, SULFATE ION, ... (5 entities in total)
• 機能のキーワード: monooxygenase, amidohydrolase-related oxygenase, oxidoreductase
• 由来する生物種: Litorilinea aerophila
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 171556.70

構造登録者

Liu, C.,Rittle, J. (登録日: 2024-05-16, 公開日: 2025-08-27, 最終更新日: 2026-03-11)

主引用文献

Liu, C.,Rao, G.,Nguyen, J.,Britt, R.D.,Rittle, J.
O 2 Activation and Enzymatic C-H Bond Activation Mediated by a Dimanganese Cofactor.
J.Am.Chem.Soc., 147:2148-2157, 2025

PubMed Abstract: Dioxygen (O) is a potent oxidant used by aerobic organisms for energy transduction and critical biosynthetic processes. Numerous metalloenzymes harness O to mediate C-H bond hydroxylation reactions, but most commonly feature iron or copper ions in their active site cofactors. In contrast, many manganese-activated enzymes─such as glutamine synthetase and isocitrate lyase─perform redox neutral chemical transformations and very few are known to activate O or C-H bonds. Here, we report that the dimanganese-metalated form of the cambialistic monooxygenase SfbO (Mn-SfbO) can efficiently mediate enzymatic C-H bond hydroxylation. The activity of the dimanganese form of SfbO toward substrate hydroxylation is comparable to that of its heterobimetallic Mn/Fe form but exhibits distinct kinetic profiles. Kinetic, spectroscopic, and structural studies invoke a mixed-valent dimanganese cofactor (MnMn) in O activation and evidence a stoichiometric role for superoxide in maturing an O-inert Mn cofactor. Computational studies support a hypothesis wherein superoxide addition to the Mn cofactor installs a critical bridging hydroxide ligand that stabilizes higher-valent manganese oxidation states. These findings establish the viability of proteinaceous dimanganese cofactors in mediating complex, multistep redox transformations.

PubMed: 39741465
DOI: 10.1021/jacs.4c16271

実験手法

X-RAY DIFFRACTION (1.39 Å)