Conformational dynamics of a multienzyme complex in anaerobic carbon fixation

• 成果类型: Article
• 署名作者: Yin, Max Dongsheng; Lemaire, Olivier N.; Jimenez, Jose Guadalupe Rosas; Belhamri, Melissa; Shevchenko, Anna; Hummer, Gerhard; Wagner, Tristan; Murphy, Bonnie J.
• 署名单位: Max Planck Society; Max Planck Society; Max Planck Society; Max Planck Society; Communaute Universite Grenoble Alpes; Universite Grenoble Alpes (UGA); CEA; Centre National de la Recherche Scientifique (CNRS)
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10342
• DOI: 10.1126/science.adr9672
• 发表日期: 2025-01-31
• 页码: 498-504
• 关键词: dehydrogenase/acetyl-coa synthase; iron-sulfur protein; monoxide dehydrogenase; crystal-structure; cryo-em; rhodospirillum-rubrum; energy-conservation; electron; cluster; activation

摘要

In the ancient microbial Wood-Ljungdahl pathway, carbon dioxide (CO2) is fixed in a multistep process that ends with acetyl-coenzyme A (acetyl-CoA) synthesis at the bifunctional carbon monoxide dehydrogenase/acetyl-CoA synthase complex (CODH/ACS). In this work, we present structural snapshots of the CODH/ACS from the gas-converting acetogen Clostridium autoethanogenum, characterizing the molecular choreography of the overall reaction, including electron transfer to the CODH for CO2 reduction, methyl transfer from the corrinoid iron-sulfur protein (CoFeSP) partner to the ACS active site, and acetyl-CoA production. Unlike CODH, the multidomain ACS undergoes large conformational changes to form an internal connection to the CODH active site, accommodate the CoFeSP for methyl transfer, and protect the reaction intermediates. Altogether, the structures allow us to draw a detailed reaction mechanism of this enzyme, which is crucial for CO2 fixation in anaerobic organisms.