Succinate : quinone oxidoreductases - what can we learn from Wolinella succinogenes quinol : fumarate reductase?

Authors
Citation
Crd. Lancaster, Succinate : quinone oxidoreductases - what can we learn from Wolinella succinogenes quinol : fumarate reductase?, FEBS LETTER, 504(3), 2001, pp. 133-141
Citations number
40
Categorie Soggetti
Biochemistry & Biophysics
Journal title
FEBS LETTERS
ISSN journal
00145793 → ACNP
Volume
504
Issue
3
Year of publication
2001
Pages
133 - 141
Database
ISI
SICI code
0014-5793(20010831)504:3<133:S:QO-W>2.0.ZU;2-7
Abstract
The structure of Wolinella succinogenes quinol:fumarate reductase by X-ray crystallography has been determined at 2.2-Angstrom resolution [Lancaster e t al. (1999), Nature 402, 377-385]. Based on the structure of the three pro tein subunits A, B, and C and the arrangement of the six prosthetic groups (a covalently bound FAD, three iron-sulphur clusters, and two haem b groups ) a pathway of electron transfer from the quinol-oxidising dihaem cytochrom e b in the membrane to the site of fumarate reduction in the hydrophilic su bunit A has been proposed. By combining the results from site-directed muta genesis, functional and electrochemical characterisation, and X-ray crystal lography, a residue was identified which is essential for menaquinol oxidat ion. [Lancaster et al. (2000), Proc. Natl. Acad. Sci. USA 97, 13051-13056]. The location of this residue in the structure suggests that the coupling o f the oxidation of menaquinol to the reduction of fumarate in dihaem-contai ning succinate:quinone oxidoreductases could be associated with the generat ion of a transmembrane electrochemical potential. Based on crystallographic analysis of three different crystal forms of the enzyme and the results fr om site-directed mutagenesis, we have derived a mechanism of fumarate reduc tion and succinate oxidation [Lancaster et al. (2001) Eur. J. Biochem. 268, 1820-1827], which should be generally relevant throughout the superfamily of succinate:quinone oxidoreductases. (C) 2001 Federation of European Bioch emical Societies. Published by Elsevier Science B.V. All rights reserved.