8S7X

Methyl-coenzyme M reductase activation complex without the A2 component

8S7X の概要

• エントリーDOI: 10.2210/pdb8s7x/pdb
• EMDBエントリー: 19788
• 分子名称: Methyl-coenzyme M reductase subunit gamma, O-PHOSPHONO-N-{(2E)-7-[(2-SULFOETHYL)DITHIO]HEPT-2-ENOYL}-L-THREONINE, 1-THIOETHANESULFONIC ACID, ... (13 entities in total)
• 機能のキーワード: methyl-coenzyme m reductase, activation complex, iron-sulfur clusters, oxidoreductase
• 由来する生物種: Methanococcus maripaludis; 詳細
• タンパク質・核酸の鎖数: 11
• 化学式量合計: 428461.74

構造登録者

Ramirez-Amador, F.,Paul, S.,Kumar, A.,Schuller, J.M. (登録日: 2024-03-04, 公開日: 2025-02-26, 最終更新日: 2025-07-02)

主引用文献

Ramirez-Amador, F.,Paul, S.,Kumar, A.,Lorent, C.,Keller, S.,Bohn, S.,Nguyen, T.,Lometto, S.,Vlegels, D.,Kahnt, J.,Deobald, D.,Abendroth, F.,Vazquez, O.,Hochberg, G.,Scheller, S.,Stripp, S.T.,Schuller, J.M.
Structure of the ATP-driven methyl-coenzyme M reductase activation complex.
Nature, 642:814-821, 2025

PubMed Abstract: Methyl-coenzyme M reductase (MCR) is the enzyme responsible for nearly all biologically generated methane. Its active site comprises coenzyme F, a porphyrin-based cofactor with a central nickel ion that is active exclusively in the Ni(I) state. How methanogenic archaea perform the reductive activation of F represents a major gap in our understanding of one of the most ancient bioenergetic systems in nature. Here we purified and characterized the MCR activation complex from Methanococcus maripaludis. McrC, a small subunit encoded in the mcr operon, co-purifies with the methanogenic marker proteins Mmp7, Mmp17, Mmp3 and the A2 component. We demonstrated that this complex can activate MCR in vitro in a strictly ATP-dependent manner, enabling the formation of methane. In addition, we determined the cryo-electron microscopy structure of the MCR activation complex exhibiting different functional states with local resolutions reaching 1.8-2.1 Å. Our data revealed three complex iron-sulfur clusters that formed an electron transfer pathway towards F. Topology and electron paramagnetic resonance spectroscopy analyses indicate that these clusters are similar to the [8Fe-9S-C] cluster, a maturation intermediate of the catalytic cofactor in nitrogenase. Altogether, our findings offer insights into the activation mechanism of MCR and prospects on the early evolution of nitrogenase.

PubMed: 40240609
DOI: 10.1038/s41586-025-08890-7

実験手法

ELECTRON MICROSCOPY (2.78 Å)