title: Atypical composition and structure of the mitochondrial dimeric ATP synthase from Euglena gracilis.
abstract: Mitochondrial respiratory-chain complexes from Euglenozoa comprise classical subunits described in other eukaryotes (i.e. mammals and fungi) and subunits that are restricted to Euglenozoa (e.g. Euglena gracilis and Trypanosoma brucei). Here we studied the mitochondrial F1FO-ATP synthase (or Complex V) from the photosynthetic eukaryote E. gracilis in detail. The enzyme was purified by a two-step chromatographic procedure and its subunit composition was resolved by a three-dimensional gel electrophoresis (BN/SDS/SDS). Twenty-two different subunits were identified by mass-spectrometry analyses among which the canonical α, β, γ, δ, ε, and OSCP subunits, and at least seven subunits previously found in Trypanosoma. The ADP/ATP carrier was also associated to the ATP synthase into a dimeric ATP synthasome. Single-particle analysis by transmission electron microscopy of the dimeric ATP synthase indicated that the structures of both the catalytic and central rotor parts are conserved while other structural features are original. These new features include a large membrane-spanning region joining the monomers, an external peripheral stalk and a structure that goes through the membrane and reaches the inter membrane space below the c-ring, the latter having not been reported for any mitochondrial F-ATPase.
authors.affiliation: Department of Electron Microscopy, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands.
authors.forename: K N Sathish
authors.initials: KNS
authors.lastname: Yadav
authors.affiliation: Genetics and Physiology of Microalgae, InBioS/Phytosystems, University of Liège, Belgium.
authors.forename: Héctor V
authors.initials: HV
authors.lastname: Miranda-Astudillo
authors.affiliation: Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico.
authors.forename: Lilia
authors.initials: L
authors.lastname: Colina-Tenorio
authors.affiliation: InBioS/Centre for Protein Engineering, University of Liège, Belgium.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Bouillenne
authors.affiliation: Institut des Sciences de la Vie, Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
authors.forename: Hervé
authors.initials: H
authors.lastname: Degand
authors.affiliation: Institut des Sciences de la Vie, Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Morsomme
authors.affiliation: Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico.
authors.forename: Diego
authors.initials: D
authors.lastname: González-Halphen
authors.affiliation: Department of Electron Microscopy, Groningen Biological Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands. Electronic address: e.j.boekema@rug.nl.
authors.forename: Egbert J
authors.initials: EJ
authors.lastname: Boekema
authors.affiliation: Genetics and Physiology of Microalgae, InBioS/Phytosystems, University of Liège, Belgium. Electronic address: Pierre.cardol@ulg.ac.be.
authors.forename: Pierre
authors.initials: P
authors.lastname: Cardol
mesh_terms: D005056:Euglena gracilis / Q000201:enzymology*; D008854:Microscopy, Electron; D025261:Mitochondrial Proton-Translocating ATPases / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D055503:Protein Multimerization; D021122:Protein Subunits / Q000032:analysis
chemical_list: D021122:Protein Subunits; D025261:Mitochondrial Proton-Translocating ATPases
keywords: ATP synthasome; Dimeric mitochondrial complex V; Electron microscopy; Euglenozoa; F(1)F(O) ATP synthase; Trypanosomatidae