Format

Send to

Choose Destination
See comment in PubMed Commons below
FEBS J. 2012 Dec;279(24):4444-52. doi: 10.1111/febs.12031. Epub 2012 Nov 8.

Electron transport during aceticlastic methanogenesis by Methanosarcina acetivorans involves a sodium-translocating Rnf complex.

Author information

1
Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt/Main, Germany.

Abstract

The anaerobic methanogenic archaeon Methanosarcina acetivorans lives under extreme energy limitation. Methanogenesis from acetate as carried out by M. acetivorans involves an anaerobic electron transport chain with ferredoxin as electron donor and heterodisulfide as electron acceptor, and so far only the heterodisulfide reductase has been shown to translocate H(+) . Here, we describe a second Na(+) -translocating coupling site in this electron transport chain. Inside-out membrane vesicles of M. acetivorans catalyzed Na(+) transport coupled to an electron transport catalyzed by the ferredoxin:heterodisulfide oxidoreductase activity. Ionophore studies revealed that Na(+) transport was primary and electrogenic. A ∆rnf mutant was unable to grow on acetate and the ferredoxin:heterodisulfide oxidoreductase-coupled Na(+) transport was abolished. These data are consistent with the hypothesis that the Rnf complex of M. acetivorans is an Na(+) -translocating coupling site and the entry point of electrons derived from reduced ferredoxin into the electron transport chain leading to the heterodisulfide.

PMID:
23066798
DOI:
10.1111/febs.12031
[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Wiley
    Loading ...
    Support Center