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Mizutani M, Kuroda S, Oku M, Aoki W, Masuya T, Miyoshi H, Murai M. Identification of proteins involved in intracellular ubiquinone trafficking in Saccharomyces cerevisiae using artificial ubiquinone probe. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149147. [PMID: 38906315 DOI: 10.1016/j.bbabio.2024.149147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/28/2024] [Accepted: 06/13/2024] [Indexed: 06/23/2024]
Abstract
Ubiquinone (UQ) is an essential player in the respiratory electron transfer system. In Saccharomyces cerevisiae strains lacking the ability to synthesize UQ6, exogenously supplied UQs can be taken up and delivered to mitochondria through an unknown mechanism, restoring the growth of UQ6-deficient yeast in non-fermentable medium. Since elucidating the mechanism responsible may markedly contribute to therapeutic strategies for patients with UQ deficiency, many attempts have been made to identify the machinery involved in UQ trafficking in the yeast model. However, definite experimental evidence of the direct interaction of UQ with a specific protein(s) has not yet been demonstrated. To gain insight into intracellular UQ trafficking via a chemistry-based strategy, we synthesized a hydrophobic UQ probe (pUQ5), which has a photoreactive diazirine group attached to a five-unit isoprenyl chain and a terminal alkyne to visualize and/or capture the labeled proteins via click chemistry. pUQ5 successfully restored the growth of UQ6-deficient S. cerevisiae (Δcoq2) on a non-fermentable carbon source, indicating that this UQ was taken up and delivered to mitochondria, and served as a UQ substrate of respiratory enzymes. Through photoaffinity labeling of the mitochondria isolated from Δcoq2 yeast cells cultured in the presence of pUQ5, we identified many labeled proteins, including voltage-dependent anion channel 1 (VDAC1) and cytochrome c oxidase subunit 3 (Cox3). The physiological relevance of UQ binding to these proteins is discussed.
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Affiliation(s)
- Mirai Mizutani
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Seina Kuroda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Masahide Oku
- Department of Bioscience and Biotechnology, Faculty of Bioenvironmental Sciences, Kyoto University of Advanced Science, Kameoka, Japan
| | - Wataru Aoki
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Japan
| | - Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
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2
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Abou-Hamdan A, Mahler R, Grossenbacher P, Biner O, Sjöstrand D, Lochner M, Högbom M, von Ballmoos C. Functional design of bacterial superoxide:quinone oxidoreductase. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148583. [PMID: 35671795 DOI: 10.1016/j.bbabio.2022.148583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 05/10/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
The superoxide anion - molecular oxygen reduced by a single electron - is produced in large amounts by enzymatic and adventitious reactions. It can perform a range of cellular functions, including bacterial warfare and iron uptake, signalling and host immune response in eukaryotes. However, it also serves as precursor for more deleterious species such as the hydroxyl anion or peroxynitrite and defense mechanisms to neutralize superoxide are important for cellular health. In addition to the soluble proteins superoxide dismutase and superoxide reductase, recently the membrane embedded diheme cytochrome b561 (CybB) from E. coli has been proposed to act as a superoxide:quinone oxidoreductase. Here, we confirm superoxide and cellular ubiquinones or menaquinones as natural substrates and show that quinone binding to the enzyme accelerates the reaction with superoxide. The reactivity of the substrates is in accordance with the here determined midpoint potentials of the two b hemes (+48 and -23 mV / NHE). Our data suggest that the enzyme can work near the diffusion limit in the forward direction and can also catalyse the reverse reaction efficiently under physiological conditions. The data is discussed in the context of described cytochrome b561 proteins and potential physiological roles of CybB.
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Affiliation(s)
- Abbas Abou-Hamdan
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Roman Mahler
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Philipp Grossenbacher
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland
| | - Olivier Biner
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland; Department of Plant and Microbial Biology, University of Zürich, 8008 Zürich, Switzerland
| | - Dan Sjöstrand
- Stockholm center for Biomembrane Research, Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden
| | - Martin Lochner
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012 Bern, Switzerland
| | - Martin Högbom
- Stockholm center for Biomembrane Research, Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden
| | - Christoph von Ballmoos
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, 3012 Bern, Switzerland.
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3
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Saito K, Kurasawa K, Takino C, Kuwahara S, Enomoto M. Asymmetric total synthesis of (–)-rossinone A. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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4
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Ito T, Murai M, Ninokura S, Kitazumi Y, Mezic KG, Cress BF, Koffas MAG, Morgan JE, Barquera B, Miyoshi H. Identification of the binding sites for ubiquinone and inhibitors in the Na +-pumping NADH-ubiquinone oxidoreductase from Vibrio cholerae by photoaffinity labeling. J Biol Chem 2017; 292:7727-7742. [PMID: 28298441 DOI: 10.1074/jbc.m117.781393] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 03/11/2017] [Indexed: 12/30/2022] Open
Abstract
The Na+-pumping NADH-quinone oxidoreductase (Na+-NQR) is the first enzyme of the respiratory chain and the main ion transporter in many marine and pathogenic bacteria, including Vibrio cholerae The V. cholerae Na+-NQR has been extensively studied, but its binding sites for ubiquinone and inhibitors remain controversial. Here, using a photoreactive ubiquinone PUQ-3 as well as two aurachin-type inhibitors [125I]PAD-1 and [125I]PAD-2 and photoaffinity labeling experiments on the isolated enzyme, we demonstrate that the ubiquinone ring binds to the NqrA subunit in the regions Leu-32-Met-39 and Phe-131-Lys-138, encompassing the rear wall of a predicted ubiquinone-binding cavity. The quinolone ring and alkyl side chain of aurachin bound to the NqrB subunit in the regions Arg-43-Lys-54 and Trp-23-Gly-89, respectively. These results indicate that the binding sites for ubiquinone and aurachin-type inhibitors are in close proximity but do not overlap one another. Unexpectedly, although the inhibitory effects of PAD-1 and PAD-2 were almost completely abolished by certain mutations in NqrB (i.e. G140A and E144C), the binding reactivities of [125I]PAD-1 and [125I]PAD-2 to the mutated enzymes were unchanged compared with those of the wild-type enzyme. We also found that photoaffinity labeling by [125I]PAD-1 and [125I]PAD-2, rather than being competitively suppressed in the presence of other inhibitors, is enhanced under some experimental conditions. To explain these apparently paradoxical results, we propose models for the catalytic reaction of Na+-NQR and its interactions with inhibitors on the basis of the biochemical and biophysical results reported here and in previous work.
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Affiliation(s)
- Takeshi Ito
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan and
| | - Masatoshi Murai
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan and
| | - Satoshi Ninokura
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan and
| | - Yuki Kitazumi
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan and
| | - Katherine G Mezic
- the Departments of Biological Sciences and.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Brady F Cress
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180.,Chemical and Biological Engineering
| | - Mattheos A G Koffas
- the Departments of Biological Sciences and.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180.,Chemical and Biological Engineering
| | - Joel E Morgan
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Blanca Barquera
- the Departments of Biological Sciences and.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180
| | - Hideto Miyoshi
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan and
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5
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Murai M, Okuda A, Yamamoto T, Shinohara Y, Miyoshi H. Synthetic Ubiquinones Specifically Bind to Mitochondrial Voltage-Dependent Anion Channel 1 (VDAC1) in Saccharomyces cerevisiae Mitochondria. Biochemistry 2017; 56:570-581. [DOI: 10.1021/acs.biochem.6b01011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Masatoshi Murai
- Division
of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Ayaka Okuda
- Division
of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Takenori Yamamoto
- Institute
for Genome Research, University of Tokushima, Kuramotocho-3, Tokushima 770-8503, Japan
| | - Yasuo Shinohara
- Institute
for Genome Research, University of Tokushima, Kuramotocho-3, Tokushima 770-8503, Japan
| | - Hideto Miyoshi
- Division
of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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6
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Herstad G, Molesworth PP, Miller CM, Benneche T, Tius MA. Ring-closing metathesis in an enantioselective synthesis of the macrocyclic core of crassin acetate. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.02.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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7
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Murai M, Matsunobu K, Kudo S, Ifuku K, Kawamukai M, Miyoshi H. Identification of the Binding Site of the Quinone-Head Group in Mitochondrial Coq10 by Photoaffinity Labeling. Biochemistry 2014; 53:3995-4003. [DOI: 10.1021/bi500347s] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | | | | | - Makoto Kawamukai
- Faculty of Life and Environmental
Science, Shimane University, 1060 Nishikawatsu, Matsue 690-8504, Japan
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8
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Masuya T, Murai M, Ifuku K, Morisaka H, Miyoshi H. Site-Specific Chemical Labeling of Mitochondrial Respiratory Complex I through Ligand-Directed Tosylate Chemistry. Biochemistry 2014; 53:2307-17. [DOI: 10.1021/bi500205x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, and ‡Division of
Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, and ‡Division of
Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kentaro Ifuku
- Division of Applied Life Sciences, Graduate School of Agriculture, and ‡Division of
Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hironobu Morisaka
- Division of Applied Life Sciences, Graduate School of Agriculture, and ‡Division of
Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, and ‡Division of
Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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9
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Structural insight into the type-II mitochondrial NADH dehydrogenases. Nature 2012; 491:478-82. [PMID: 23086143 DOI: 10.1038/nature11541] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Accepted: 08/29/2012] [Indexed: 01/13/2023]
Abstract
The single-component type-II NADH dehydrogenases (NDH-2s) serve as alternatives to the multisubunit respiratory complex I (type-I NADH dehydrogenase (NDH-1), also called NADH:ubiquinone oxidoreductase; EC 1.6.5.3) in catalysing electron transfer from NADH to ubiquinone in the mitochondrial respiratory chain. The yeast NDH-2 (Ndi1) oxidizes NADH on the matrix side and reduces ubiquinone to maintain mitochondrial NADH/NAD(+) homeostasis. Ndi1 is a potential therapeutic agent for human diseases caused by complex I defects, particularly Parkinson's disease, because its expression restores the mitochondrial activity in animals with complex I deficiency. NDH-2s in pathogenic microorganisms are viable targets for new antibiotics. Here we solve the crystal structures of Ndi1 in its substrate-free, NADH-, ubiquinone- and NADH-ubiquinone-bound states, to help understand the catalytic mechanism of NDH-2s. We find that Ndi1 homodimerization through its carboxy-terminal domain is critical for its catalytic activity and membrane targeting. The structures reveal two ubiquinone-binding sites (UQ(I) and UQ(II)) in Ndi1. NADH and UQ(I) can bind to Ndi1 simultaneously to form a substrate-protein complex. We propose that UQ(I) interacts with FAD to act as an intermediate for electron transfer, and that NADH transfers electrons through this FAD-UQ(I) complex to UQ(II). Together our data reveal the regulatory and catalytic mechanisms of Ndi1 and may facilitate the development or targeting of NDH-2s for potential therapeutic applications.
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10
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The structure of the yeast NADH dehydrogenase (Ndi1) reveals overlapping binding sites for water- and lipid-soluble substrates. Proc Natl Acad Sci U S A 2012; 109:15247-52. [PMID: 22949654 DOI: 10.1073/pnas.1210059109] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bioenergy is efficiently produced in the mitochondria by the respiratory system consisting of complexes I-V. In various organisms, complex I can be replaced by the alternative NADH-quinone oxidoreductase (NDH-2), which catalyzes the transfer of an electron from NADH via FAD to quinone, without proton pumping. The Ndi1 protein from Saccharomyces cerevisiae is a monotopic membrane protein, directed to the matrix. A number of studies have investigated the potential use of Ndi1 as a therapeutic agent against complex I disorders, and the NDH-2 enzymes have emerged as potential therapeutic targets for treatments against the causative agents of malaria and tuberculosis. Here we present the crystal structures of Ndi1 in its substrate-free, NAD(+)- and ubiquinone- (UQ2) complexed states. The structures reveal that Ndi1 is a peripheral membrane protein forming an intimate dimer, in which packing of the monomeric units within the dimer creates an amphiphilic membrane-anchor domain structure. Crucially, the structures of the Ndi1-NAD(+) and Ndi1-UQ2 complexes show overlapping binding sites for the NAD(+) and quinone substrates.
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11
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Respiratory chain analysis of Zymomonas mobilis mutants producing high levels of ethanol. Appl Environ Microbiol 2012; 78:5622-9. [PMID: 22660712 DOI: 10.1128/aem.00733-12] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously isolated respiratory-deficient mutant (RDM) strains of Zymomonas mobilis, which exhibited greater growth and enhanced ethanol production under aerobic conditions. These RDM strains also acquired thermotolerance. Morphologically, the cells of all RDM strains were shorter compared to the wild-type strain. We investigated the respiratory chains of these RDM strains and found that some RDM strains lost NADH dehydrogenase activity, whereas others exhibited reduced cytochrome bd-type ubiquinol oxidase or ubiquinol peroxidase activities. Complementation experiments restored the wild-type phenotype. Some RDM strains seem to have certain mutations other than the corresponding respiratory chain components. RDM strains with deficient NADH dehydrogenase activity displayed the greatest amount of aerobic growth, enhanced ethanol production, and thermotolerance. Nucleotide sequence analysis revealed that all NADH dehydrogenase-deficient strains were mutated within the ndh gene, which includes insertion, deletion, or frameshift. These results suggested that the loss of NADH dehydrogenase activity permits the acquisition of higher aerobic growth, enhanced ethanol production, and thermotolerance in this industrially important strain.
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12
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Casutt MS, Nedielkov R, Wendelspiess S, Vossler S, Gerken U, Murai M, Miyoshi H, Möller HM, Steuber J. Localization of ubiquinone-8 in the Na+-pumping NADH:quinone oxidoreductase from Vibrio cholerae. J Biol Chem 2011; 286:40075-82. [PMID: 21885438 DOI: 10.1074/jbc.m111.224980] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Na(+) is the second major coupling ion at membranes after protons, and many pathogenic bacteria use the sodium-motive force to their advantage. A prominent example is Vibrio cholerae, which relies on the Na(+)-pumping NADH:quinone oxidoreductase (Na(+)-NQR) as the first complex in its respiratory chain. The Na(+)-NQR is a multisubunit, membrane-embedded NADH dehydrogenase that oxidizes NADH and reduces quinone to quinol. Existing models describing redox-driven Na(+) translocation by the Na(+)-NQR are based on the assumption that the pump contains four flavins and one FeS cluster. Here we show that the large, peripheral NqrA subunit of the Na(+)-NQR binds one molecule of ubiquinone-8. Investigations of the dynamic interaction of NqrA with quinones by surface plasmon resonance and saturation transfer difference NMR reveal a high affinity, which is determined by the methoxy groups at the C-2 and C-3 positions of the quinone headgroup. Using photoactivatable quinone derivatives, it is demonstrated that ubiquinone-8 bound to NqrA occupies a functional site. A novel scheme of electron transfer in Na(+)-NQR is proposed that is initiated by NADH oxidation on subunit NqrF and leads to quinol formation on subunit NqrA.
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Affiliation(s)
- Marco S Casutt
- Department of Neuropathology, University of Freiburg, 79106 Freiburg, Germany
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13
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Yang Y, Yamashita T, Nakamaru-Ogiso E, Hashimoto T, Murai M, Igarashi J, Miyoshi H, Mori N, Matsuno-Yagi A, Yagi T, Kosaka H. Reaction mechanism of single subunit NADH-ubiquinone oxidoreductase (Ndi1) from Saccharomyces cerevisiae: evidence for a ternary complex mechanism. J Biol Chem 2011; 286:9287-97. [PMID: 21220430 PMCID: PMC3059053 DOI: 10.1074/jbc.m110.175547] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 12/27/2010] [Indexed: 11/06/2022] Open
Abstract
The flavoprotein rotenone-insensitive internal NADH-ubiquinone (UQ) oxidoreductase (Ndi1) is a member of the respiratory chain in Saccharomyces cerevisiae. We reported previously that bound UQ in Ndi1 plays a key role in preventing the generation of reactive oxygen species. Here, to elucidate this mechanism, we investigated biochemical properties of Ndi1 and its mutants in which highly conserved amino acid residues (presumably involved in NADH and/or UQ binding sites) were replaced. We found that wild-type Ndi1 formed a stable charge transfer (CT) complex (around 740 nm) with NADH, but not with NADPH, under anaerobic conditions. The intensity of the CT absorption band was significantly increased by the presence of bound UQ or externally added n-decylbenzoquinone. Interestingly, however, when Ndi1 was exposed to air, the CT band transiently reached the same maximum level regardless of the presence of UQ. This suggests that Ndi1 forms a ternary complex with NADH and UQ, but the role of UQ in withdrawing an electron can be substitutable with oxygen. Proteinase K digestion analysis showed that NADH (but not NADPH) binding induces conformational changes in Ndi1. The kinetic study of wild-type and mutant Ndi1 indicated that there is no overlap between NADH and UQ binding sites. Moreover, we found that the bound UQ can reversibly dissociate from Ndi1 and is thus replaceable with other quinones in the membrane. Taken together, unlike other NAD(P)H-UQ oxidoreductases, the Ndi1 reaction proceeds through a ternary complex (not a ping-pong) mechanism. The bound UQ keeps oxygen away from the reduced flavin.
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Affiliation(s)
- Yu Yang
- From the Departments of Cardiovascular Physiology and
| | | | - Eiko Nakamaru-Ogiso
- Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6059
| | | | - Masatoshi Murai
- Division of Applied Life Science, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan, and
| | | | - Hideto Miyoshi
- Division of Applied Life Science, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan, and
| | - Nozomu Mori
- Otolaryngology, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa 761-0793, Japan
| | - Akemi Matsuno-Yagi
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037
| | - Takao Yagi
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037
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14
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Villegas JM, Volentini SI, Rintoul MR, Rapisarda VA. Amphipathic C-terminal region of Escherichia coli NADH dehydrogenase-2 mediates membrane localization. Arch Biochem Biophys 2010; 505:155-9. [PMID: 20933494 DOI: 10.1016/j.abb.2010.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 10/02/2010] [Accepted: 10/04/2010] [Indexed: 01/19/2023]
Abstract
Respiratory NADH dehydrogenase-2 (NDH-2) of Escherichia coli is a membrane-bound flavoprotein. Bioinformatics approaches suggested the involvement of NDH-2 C-terminal region in membrane anchorage. Here, we demonstrated that NDH-2 is a peripheral membrane protein and that its predicted C-terminal amphipathic Arg390-Ala406 helix is sufficient to bind the protein to lipid membranes. Additionally, a cytosolic NDH-2 protein (Trun-3), lacking the last 43 aminoacids, was purified and characterized. FAD cofactor was absent in purified Trun-3. Upon the addition of FAD, Trun-3 maximum velocity was similar to native NDH-2 rate with ferricyanide and MTT acceptors. However, Trun-3 activity was around 5-fold lower with quinones. No significant difference in K(m) values was observed for both enzymes. For the first time, an active and water soluble NDH-2 was obtained, representing a major improvement for structural/functional characterizations.
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Affiliation(s)
- Josefina M Villegas
- Departamento Bioquímica de la Nutrición, Instituto Superior de Investigaciones Biológicas, Universidad Nacional de Tucumán, San Miguel de Tucumán, Argentina
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15
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Current awareness on yeast. Yeast 2010. [DOI: 10.1002/yea.1721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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