Academic Journal
Thiol‐Disulfide Exchange Kinetics and Redox Potential of the Coenzyme M and Coenzyme B Heterodisulfide, an Electron Acceptor Coupled to Energy Conservation in Methanogenic Archaea
| العنوان: | Thiol‐Disulfide Exchange Kinetics and Redox Potential of the Coenzyme M and Coenzyme B Heterodisulfide, an Electron Acceptor Coupled to Energy Conservation in Methanogenic Archaea |
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| المؤلفون: | Laird, Maxime Gabriel, Adlung, Norman, Koivisto, Jari J, Scheller, Silvan |
| المصدر: | Laird , M G , Adlung , N , Koivisto , J J & Scheller , S 2024 , ' Thiol‐Disulfide Exchange Kinetics and Redox Potential of the Coenzyme M and Coenzyme B Heterodisulfide, an Electron Acceptor Coupled to Energy Conservation in Methanogenic Archaea ' , ChemBioChem , vol. 25 , no. 1 , e202300595 . https://doi.org/10.1002/cbic.202300595 |
| سنة النشر: | 2024 |
| مصطلحات موضوعية: | cofactors, heterodisulfide, kinetics, methanogenesis, NMR spectroscopy, redox potentials |
| الوصف: | Methanogenic and methanotrophic archaea play important roles in the global carbon cycle by interconverting CO2 and methane. To conserve energy from these metabolic pathways that happen close to the thermodynamic equilibrium, specific electron carriers have evolved to balance the redox potentials between key steps. Reduced ferredoxins required to activate CO2 are provided by energetical coupling to the reduction of the high‐potential heterodisulfide (HDS) of coenzyme M (2‐mercaptoethanesulfonate) and coenzyme B (7‐mercaptoheptanoylthreonine phosphate).While the standard redox potential of this important HDS has been determined previously to be ‐143 mV (Tietze et al. 2003 DOI:10.1002/cbic.200390053), we have measured thiol disulfide exchange kinetics and reassessed this value by equilibrating thiol‐disulfide mixtures of coenzyme M, coenzyme B and mercaptoethanol. We determined the redox potential of the HDS of coenzyme M and coenzyme B to be ‐16.4 ± 1.7 mV relative to the reference thiol mercaptoethanol (E0’ = ‐264 mV). The resulting E0’ values are ‐281 mV for the HDS, ‐271 mV for the homodisulfide of coenzyme M, and ‐270 mV for the homodisulfide of coenzyme B. We discuss the importance of these updated values for the physiology of methanogenic and methanotrophic archaea and their implications in terms of energy conservation. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1002/cbic.202300595 |
| الاتاحة: | https://cris.vtt.fi/en/publications/f971c2ec-4410-440b-9b2c-5a2ab8cbbef8 https://doi.org/10.1002/cbic.202300595 http://www.scopus.com/inward/record.url?scp=85175257931&partnerID=8YFLogxK |
| Rights: | info:eu-repo/semantics/openAccess |
| رقم الانضمام: | edsbas.9F273D2E |
| قاعدة البيانات: | BASE |
| DOI: | 10.1002/cbic.202300595 |
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