Crystallization of mitochondrial respiratory complex II from chicken heart: A membrane-protein complex diffracting to 2.0 Å

University of California, Berkeley, Berkeley, California, United States
Acta Crystallographica Section D Biological Crystallography (Impact Factor: 2.67). 05/2005; 61(Pt 4):380-7. DOI: 10.1107/S0907444905000181
Source: PubMed


A procedure is presented for preparation of diffraction-quality crystals of a vertebrate mitochondrial respiratory complex II. The crystals have the potential to diffract to at least 2.0 A with optimization of post-crystal-growth treatment and cryoprotection. This should allow determination of the structure of this important and medically relevant membrane-protein complex at near-atomic resolution and provide great detail of the mode of binding of substrates and inhibitors at the two substrate-binding sites.

Full-text preview

Available from:
  • Source
    • "Crystal structures of SDH enzymes from avian [17], bacterial [18] [19] [20], and mammalian [21] sources are available. In addition, a homology model of the Saccharomyces cerevisiae SDH has been published [22]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The coupling of succinate oxidation to the reduction of ubiquinone by succinate dehydrogenase (SDH) constitutes a pivotal reaction in the aerobic generation of energy. In Saccharomyces cerevisiae, SDH is a tetramer composed of a catalytic dimer comprising a flavoprotein subunit, Sdh1p and an iron-sulfur protein, Sdh2p and a heme b-containing membrane-anchoring dimer comprising the Sdh3p and Sdh4p subunits. In order to investigate the role of heme in SDH catalysis, we constructed an S. cerevisiae strain expressing a mutant enzyme lacking the two heme axial ligands, Sdh3p His-106 and Sdh4p Cys-78. The mutant enzyme was characterized for growth on a non-fermentable carbon source, for enzyme assembly, for succinate-dependent quinone reduction and for its heme b content. Replacement of both Sdh3p His-106 and Sdh4p Cys-78 with alanine residues leads to an undetectable level of cytochrome b(562). Although enzyme assembly is slightly impaired, the apocytochrome SDH retains a significant ability to reduce quinone. The enzyme has a reduced affinity for quinone and its catalytic efficiency is reduced by an order of magnitude. To better understand the effects of the mutations, we employed atomistic molecular dynamic simulations to investigate the enzyme's structure and stability in the absence of heme. Our results strongly suggest that heme is not required for electron transport from succinate to quinone nor is it necessary for assembly of the S. cerevisiae SDH.
    Biochimica et Biophysica Acta 01/2008; 1767(12):1436-45. DOI:10.1016/j.bbabio.2007.09.008 · 4.66 Impact Factor
  • Source

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A probable mechanism of alteration of the isoenzyme composition of succinate dehydrogenase (SDH) due to differential expression of genes encoding subunit A was considered. The alteration of SDH activity during maize seed germination was investigated, and its maximal activity on day 4-5 of germination was found. The alteration of the sdh1-1 and sdh1-2 gene expression level during maize seed germination was evaluated using the quantitative polymerase chain reaction method. The presence of four forms of the studied enzymes, providing multiple SDH functions was found in maize inflorescence using electrophoresis in polyacrylamide gel.
    Biology Bulletin 06/2010; 37(3):268-276. DOI:10.1134/S1062359010030088 · 0.25 Impact Factor
Show more