6CFW

cryoEM structure of a respiratory membrane-bound hydrogenase

Summary for 6CFW

• Entry DOI: 10.2210/pdb6cfw/pdb
• EMDB information: 7468
• Descriptor: Monovalent cation/H+ antiporter subunit D, Monovalent cation/H+ antiporter subunit F, Probable membrane-bound hydrogenase subunit mbhJ, ... (16 entities in total)
• Functional Keywords: respiratory, hydrogenase, ion translocation, membrane protein
• Biological source: Pyrococcus furiosus COM1; More
• Total number of polymer chains: 14
• Total formula weight: 293216.13

Authors

Li, H.L.,Yu, H.J. (deposition date: 2018-02-17, release date: 2018-05-23, Last modification date: 2025-05-14)

Primary citation

Yu, H.,Wu, C.H.,Schut, G.J.,Haja, D.K.,Zhao, G.,Peters, J.W.,Adams, M.W.W.,Li, H.
Structure of an Ancient Respiratory System.
Cell, 173:1636-, 2018

PubMed Abstract: Hydrogen gas-evolving membrane-bound hydrogenase (MBH) and quinone-reducing complex I are homologous respiratory complexes with a common ancestor, but a structural basis for their evolutionary relationship is lacking. Here, we report the cryo-EM structure of a 14-subunit MBH from the hyperthermophile Pyrococcus furiosus. MBH contains a membrane-anchored hydrogenase module that is highly similar structurally to the quinone-binding Q-module of complex I while its membrane-embedded ion-translocation module can be divided into a H- and a Na-translocating unit. The H-translocating unit is rotated 180° in-membrane with respect to its counterpart in complex I, leading to distinctive architectures for the two respiratory systems despite their largely conserved proton-pumping mechanisms. The Na-translocating unit, absent in complex I, resembles that found in the Mrp H/Na antiporter and enables hydrogen gas evolution by MBH to establish a Na gradient for ATP synthesis near 100°C. MBH also provides insights into Mrp structure and evolution of MBH-based respiratory enzymes.

PubMed: 29754813
DOI: 10.1016/j.cell.2018.03.071

Experimental method

ELECTRON MICROSCOPY (3.7 Å)