title: Evidence of the proximity of ATP synthase subunits 6 (a) in the inner mitochondrial membrane and in the supramolecular forms of Saccharomyces cerevisiae ATP synthase.
abstract: The involvement of subunit 6 (a) in the interface between yeast ATP synthase monomers has been highlighted. Based on the formation of a disulfide bond and using the unique cysteine 23 as target, we show that two subunits 6 are close in the inner mitochondrial membrane and in the solubilized supramolecular forms of the yeast ATP synthase. In a null mutant devoid of supernumerary subunits e and g that are involved in the stabilization of ATP synthase dimers, ATP synthase monomers are close enough in the inner mitochondrial membrane to make a disulfide bridge between their subunits 6, and this proximity is maintained in detergent extract containing this enzyme. The cross-linking of cysteine 23 located in the N-terminal part of the first transmembrane helix of subunit 6 suggests that this membrane-spanning segment is in contact with its counterpart belonging to the ATP synthase monomer that faces it and participates in the monomer-monomer interface.
authors.affiliation: CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095; Université de Bordeaux, UMR 5095, 1 Rue Camille Saint Saëns, 33077 Bordeaux Cedex. Electronic address: jean.velours@ibgc.cnrs.fr.
authors.forename: Jean
authors.initials: J
authors.lastname: Velours
authors.affiliation: CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095; Université de Bordeaux, UMR 5095, 1 Rue Camille Saint Saëns, 33077 Bordeaux Cedex.
authors.forename: Claire
authors.initials: C
authors.lastname: Stines-Chaumeil
authors.affiliation: CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095; Université de Bordeaux, UMR 5095, 1 Rue Camille Saint Saëns, 33077 Bordeaux Cedex.
authors.forename: Johan
authors.initials: J
authors.lastname: Habersetzer
authors.affiliation: CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095; Université de Bordeaux, UMR 5095, 1 Rue Camille Saint Saëns, 33077 Bordeaux Cedex; CNRS, Chimie et Biologie des Membranes et des Nanoobjets, UMR 5248, Allée de Saint Hilaire, Bât B14, 33600 Pessac, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Chaignepain
authors.affiliation: CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095; Université de Bordeaux, UMR 5095, 1 Rue Camille Saint Saëns, 33077 Bordeaux Cedex.
authors.forename: Alain
authors.initials: A
authors.lastname: Dautant
authors.affiliation: CNRS, Institut de Biochimie et Génétique Cellulaires, UMR 5095; Université de Bordeaux, UMR 5095, 1 Rue Camille Saint Saëns, 33077 Bordeaux Cedex. Electronic address: daniel.brethes@ibgc.cnrs.fr.
authors.forename: Daniel
authors.initials: D
authors.lastname: Brèthes
mesh_terms: D051336:Mitochondrial Membranes / Q000201:enzymology*; D025261:Mitochondrial Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D055503:Protein Multimerization / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C501004:ATP6 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D025261:Mitochondrial Proton-Translocating ATPases