Molecular mechanism of energy conservation in polysulfide respiration

DOI: 10.1038/nsmb.1434

Authors: M. Jormakka (University of New South Wales; Centenary Institute of Cancer Medicine and Cell Biology (Australia); University of Sydney) , K. Yokoyama (Tokyo Institute of Technology; Japan Science and Technology Agency) , S. Yano (Japan Science and Technology Agency) , M. Tamakoshi (Tokyo University of Pharmacy and Life Science) , S. Akimoto (Japan Science and Technology Agency) , T. Shimamura (RIKEN SPring-8 Center; Japan Science and Technology Agency) , P. Curmi (University of New South Wales) , S. Iwata (Japan Science and Technology Agency; Imperial College London; RIKEN Genomic Sciences Center,)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nature Structural & Molecular Biology , VOL 15 (7) , PAGES 730 - 737

State: Published (Approved)
Published: June 2008

Abstract: Bacterial polysulfide reductase (PsrABC) is an integral membrane protein complex responsible for quinone-coupled reduction of polysulfide, a process important in extreme environments such as deep-sea vents and hot springs. We determined the structure of polysulfide reductase from Thermus thermophilus at 2.4-Å resolution, revealing how the PsrA subunit recognizes and reduces its unique polyanionic substrate. The integral membrane subunit PsrC was characterized using the natural substrate menaquinone-7 and inhibitors, providing a comprehensive representation of a quinone binding site and revealing the presence of a water-filled cavity connecting the quinone binding site on the periplasmic side to the cytoplasm. These results suggest that polysulfide reductase could be a key energy-conserving enzyme of the T. thermophilus respiratory chain, using polysulfide as the terminal electron acceptor and pumping protons across the membrane via a previously unknown mechanism.

Diamond Keywords: Bacteria

Subject Areas: Biology and Bio-materials

Diamond Offline Facilities: Membrane Protein Laboratory (MPL)
Instruments: NONE-No attached Diamond beamline

Added On: 19/08/2009 23:07

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags: