MtrC, an outer membrane decahaem c cytochrome required for metal reduction in Shewanella putrefaciens MR-1

Mol Microbiol. 2001 Feb;39(3):722-30. doi: 10.1046/j.1365-2958.2001.02257.x.


Shewanella putrefaciens is a facultative anaerobe that can use metal oxides as terminal electron acceptors during anaerobic respiration. Two proteins, MtrB and Cct, have been identified that are specifically involved in metal reduction. Analysis of S. putrefaciens mutants deficient in metal reduction led to the identification of two additional proteins that are involved in this process. MtrA is a periplasmic decahaem c-type cytochrome that appears to be part of the electron transport chain, which leads to Fe(III) and Mn(IV) reduction. MtrC is an outer membrane decahaem c-type cytochrome that appears to be required for the activity of the terminal Fe(III) reductase. Membrane fractions of mutants deficient in MtrC exhibited a decreased level of Fe(III) reduction compared with the wild type. We suggest that MtrC may be a component of the terminal reductase or may be required for its assembly.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Bacterial Outer Membrane Proteins / genetics
  • Bacterial Outer Membrane Proteins / metabolism*
  • Base Sequence
  • Blotting, Western
  • Cytochrome c Group / genetics
  • Cytochrome c Group / metabolism*
  • FMN Reductase*
  • Ferric Compounds / metabolism*
  • Gene Deletion
  • Manganese / metabolism
  • Molecular Sequence Data
  • NADH, NADPH Oxidoreductases / metabolism
  • Oxidation-Reduction
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Shewanella putrefaciens / enzymology*
  • Shewanella putrefaciens / genetics
  • Shewanella putrefaciens / growth & development


  • Bacterial Outer Membrane Proteins
  • Cytochrome c Group
  • Ferric Compounds
  • MtrB protein, Shewanella putrefaciens
  • Recombinant Fusion Proteins
  • Manganese
  • MtrC protein, Shewanella
  • FMN Reductase
  • NADH, NADPH Oxidoreductases
  • ferric citrate iron reductase