A 63.9 kDa periplasmic tetrahaem flavocytochrome c3, designated Ifc3, was found to be expressed in Shewanellafrigidimarina NCIMB400 grown anaerobically with ferric citrate or ferric pyrophosphate as the sole terminal electron acceptor, but not in anaerobic cultures of the bacterium with other respiratory substrates. Ifc3 was purified to homogeneity and revealed by biochemical, spectroscopic and primary structure analyses to contain four low-spin bis-His-ligated c3-haems, with midpoint reduction potentials of -73, -141, -174 and -259 mV. A low-potential flavin was present in the form of non-covalently bound FAD; the protein possessed a unidirectional fumarate reductase activity. Disruption of the chromosomal gene encoding Ifc3, ifcA, did not lead to a significant change in the rate of Fe3+ reduction in batch culture. However, during such growth the Ifc3-deficient mutant produced both a 35 kDa periplasmic c-type cytochrome and a 45 kDa membrane-associated c-type cytochrome at markedly higher levels than did the parent strain. Nucleotide sequencing data from directly upstream of ifcA indicated the presence of an open reading frame encoding a putative outer-membrane β-barrel protein of 324 amino acid residues.
Skip Nav Destination
Article navigation
September 1999
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
Research Article|
August 24 1999
Characterization of a flavocytochrome that is induced during the anaerobic respiration of Fe3+ by Shewanella frigidimarina NCIMB400
Paul S. DOBBIN;
Paul S. DOBBIN
1
*School of Biological Sciences, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich NR4 7TJ, U.K.
1To whom correspondence should be addressed (p.dobbin@uea.ac.uk).
Search for other works by this author on:
Julea N. BUTT;
Julea N. BUTT
†School of Chemical Sciences, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich NR4 7TJ, U.K.
Search for other works by this author on:
Anne K. POWELL;
Anne K. POWELL
†School of Chemical Sciences, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich NR4 7TJ, U.K.
Search for other works by this author on:
Graeme A. REID;
Graeme A. REID
‡Institute of Cell and Molecular Biology, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, U.K.
Search for other works by this author on:
David J. RICHARDSON
David J. RICHARDSON
*School of Biological Sciences, Centre for Metalloprotein Spectroscopy and Biology, University of East Anglia, Norwich NR4 7TJ, U.K.
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
March 26 1999
Revision Received:
May 28 1999
Accepted:
June 28 1999
Online ISSN: 1470-8728
Print ISSN: 0264-6021
The Biochemical Society, London © 1999
1999
Biochem J (1999) 342 (2): 439–448.
Article history
Received:
March 26 1999
Revision Received:
May 28 1999
Accepted:
June 28 1999
Citation
Paul S. DOBBIN, Julea N. BUTT, Anne K. POWELL, Graeme A. REID, David J. RICHARDSON; Characterization of a flavocytochrome that is induced during the anaerobic respiration of Fe3+ by Shewanella frigidimarina NCIMB400. Biochem J 1 September 1999; 342 (2): 439–448. doi: https://doi.org/10.1042/bj3420439
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.