title: Supramolecular organization of cytochrome c oxidase- and alternative oxidase-dependent respiratory chains in the filamentous fungus Podospora anserina.
abstract: To elucidate the molecular basis of the link between respiration and longevity, we have studied the organization of the respiratory chain of a wild-type strain and of two long-lived mutants of the filamentous fungus Podospora anserina. This established aging model is able to respire by either the standard or the alternative pathway. In the latter pathway, electrons are directly transferred from ubiquinol to the alternative oxidase and thus bypass complexes III and IV. We show that the cytochrome c oxidase pathway is organized according to the mammalian "respirasome" model (Schägger, H., and Pfeiffer, K. (2000) EMBO J. 19, 1777-1783). In contrast, the alternative pathway is composed of distinct supercomplexes of complexes I and III (i.e. I(2) and I(2)III(2)), which have not been described so far. Enzymatic analysis reveals distinct functional properties of complexes I and III belonging to either cytochrome c oxidase- or alternative oxidase-dependent pathways. By a gentle colorless-native PAGE, almost all of the ATP synthases from mitochondria respiring by either pathway were preserved in the dimeric state. Our data are of significance for the understanding of both respiratory pathways as well as lifespan control and aging.
authors.affiliation: Department of Chemistry, Physical Biochemistry, Darmstadt University of Technology, Petersenstrasse 22, D-64287 Darmstadt, Germany. f_krause@pop.tu-darmstadt.de
authors.forename: Frank
authors.initials: F
authors.lastname: Krause
authors.forename: Christian Q
authors.initials: CQ
authors.lastname: Scheckhuber
authors.forename: Alexandra
authors.initials: A
authors.lastname: Werner
authors.forename: Sascha
authors.initials: S
authors.lastname: Rexroth
authors.forename: Nicole H
authors.initials: NH
authors.lastname: Reifschneider
authors.forename: Norbert A
authors.initials: NA
authors.lastname: Dencher
authors.forename: Heinz D
authors.initials: HD
authors.lastname: Osiewacz
mesh_terms: D001203:Ascomycota / Q000201:enzymology*; D001669:Biochemical Phenomena; D001671:Biochemistry; D003902:Detergents / Q000494:pharmacology; D019281:Dimerization; D004579:Electron Transport; D003576:Electron Transport Complex IV / Q000737:chemistry* / Q000378:metabolism; D004583:Electrons; D004591:Electrophoresis, Polyacrylamide Gel; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins; D010088:Oxidoreductases / Q000378:metabolism*; D010940:Plant Proteins; D006180:Proton-Translocating ATPases / Q000378:metabolism; D013997:Time Factors; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000737:chemistry; D000099188:Alternative Oxidase
chemical_list: D003902:Detergents; D003576:Electron Transport Complex IV; D024101:Mitochondrial Proteins; D010088:Oxidoreductases; D010940:Plant Proteins; D006180:Proton-Translocating ATPases; D014451:Ubiquinone; D000099188:Alternative Oxidase; C003741:ubiquinol