1
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Ikunishi R, Otani R, Masuya T, Shinzawa-Itoh K, Shiba T, Murai M, Miyoshi H. Respiratory complex I in mitochondrial membrane catalyzes oversized ubiquinones. J Biol Chem 2023; 299:105001. [PMID: 37394006 PMCID: PMC10416054 DOI: 10.1016/j.jbc.2023.105001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 06/20/2023] [Accepted: 06/23/2023] [Indexed: 07/04/2023] Open
Abstract
NADH-ubiquinone (UQ) oxidoreductase (complex I) couples electron transfer from NADH to UQ with proton translocation in its membrane part. The UQ reduction step is key to triggering proton translocation. Structural studies have identified a long, narrow, tunnel-like cavity within complex I, through which UQ may access a deep reaction site. To elucidate the physiological relevance of this UQ-accessing tunnel, we previously investigated whether a series of oversized UQs (OS-UQs), whose tail moiety is too large to enter and transit the narrow tunnel, can be catalytically reduced by complex I using the native enzyme in bovine heart submitochondrial particles (SMPs) and the isolated enzyme reconstituted into liposomes. Nevertheless, the physiological relevance remained unclear because some amphiphilic OS-UQs were reduced in SMPs but not in proteoliposomes, and investigation of extremely hydrophobic OS-UQs was not possible in SMPs. To uniformly assess the electron transfer activities of all OS-UQs with the native complex I, here we present a new assay system using SMPs, which were fused with liposomes incorporating OS-UQ and supplemented with a parasitic quinol oxidase to recycle reduced OS-UQ. In this system, all OS-UQs tested were reduced by the native enzyme, and the reduction was coupled with proton translocation. This finding does not support the canonical tunnel model. We propose that the UQ reaction cavity is flexibly open in the native enzyme to allow OS-UQs to access the reaction site, but their access is obstructed in the isolated enzyme as the cavity is altered by detergent-solubilizing from the mitochondrial membrane.
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Affiliation(s)
- Ryo Ikunishi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Ryohei Otani
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Kyoko Shinzawa-Itoh
- Department of Life Science, Graduate School of Life Science, University of Hyogo, Hyogo, Japan
| | - Tomoo Shiba
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto, Japan
| | - Masatoshi Murai
- 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.
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2
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Tsuji A, Masuya T, Arichi N, Inuki S, Murai M, Miyoshi H, Ohno H. Discovery of Bis-sulfonamides as Novel Inhibitors of Mitochondrial NADH-Quinone Oxidoreductase (Complex I). ACS Med Chem Lett 2023; 14:211-216. [PMID: 36793437 PMCID: PMC9923842 DOI: 10.1021/acsmedchemlett.2c00504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 01/16/2023] [Indexed: 01/25/2023] Open
Abstract
Mitochondrial oxidative phosphorylation (OXPHOS) is an essential cellular metabolic process that generates ATP. The enzymes involved in OXPHOS are considered to be promising druggable targets. Through screening of an in-house synthetic library with bovine heart submitochondrial particles, we identified a unique symmetric bis-sulfonamide, KPYC01112 (1) as an inhibitor targeting NADH-quinone oxidoreductase (complex I). Structural modifications of KPYC01112 (1) led to the discovery of the more potent inhibitors 32 and 35 possessing long alkyl chains (IC50 = 0.017 and 0.014 μM, respectively). A photoaffinity labeling experiment using a newly synthesized photoreactive bis-sulfonamide ([125I]-43) revealed that it binds to the 49-kDa, PSST, and ND1 subunits which make up the quinone-accessing cavity of complex I.
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Affiliation(s)
- Atsuhito Tsuji
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Kyoto 606-8501, Japan
| | - Takahiro Masuya
- Division
of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Norihito Arichi
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Kyoto 606-8501, Japan
| | - Shinsuke Inuki
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Kyoto 606-8501, Japan
| | - Masatoshi Murai
- Division
of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division
of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Hiroaki Ohno
- Graduate
School of Pharmaceutical Sciences, Kyoto
University, Kyoto 606-8501, Japan
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3
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Maurer L, Kang H, Smyers M, Klei L, Cheng J, Trotta M, Hu D, Ekambaram P, Murai M, Nikolovska-Coleska Z, Chen B, Lucas P, McAllister-Lucas L. BLOCKING THE BCL10-MALT1 INTERACTION IN DIFFUSE LARGE B-CELL LYMPHOMA. Leuk Res 2022. [DOI: 10.1016/s0145-2126(22)00224-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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4
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Ishikawa M, Masuya T, Kuroda S, Uno S, Butler NL, Foreman S, Murai M, Barquera B, Miyoshi H. The side chain of ubiquinone plays a critical role in Na + translocation by the NADH-ubiquinone oxidoreductase (Na +-NQR) from Vibrio cholerae. Biochim Biophys Acta Bioenerg 2022; 1863:148547. [PMID: 35337841 DOI: 10.1016/j.bbabio.2022.148547] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/18/2022] [Accepted: 03/17/2022] [Indexed: 11/19/2022]
Abstract
The Na+-pumping NADH-ubiquinone (UQ) oxidoreductase (Na+-NQR) is an essential bacterial respiratory enzyme that generates a Na+ gradient across the cell membrane. However, the mechanism that couples the redox reactions to Na+ translocation remains unknown. To address this, we examined the relation between reduction of UQ and Na+ translocation using a series of synthetic UQs with Vibrio cholerae Na+-NQR reconstituted into liposomes. UQ0 that has no side chain and UQCH3 and UQC2H5, which have methyl and ethyl side chains, respectively, were catalytically reduced by Na+-NQR, but their reduction generated no membrane potential, indicating that the overall electron transfer and Na+ translocation are not coupled. While these UQs were partly reduced by electron leak from the cofactor(s) located upstream of riboflavin, this complete loss of Na+ translocation cannot be explained by the electron leak. Lengthening the UQ side chain to n-propyl (C3H7) or longer significantly restored Na+ translocation. It has been considered that Na+ translocation is completed when riboflavin, a terminal redox cofactor residing within the membrane, is reduced. In this view, the role of UQ is simply to accept electrons from the reduced riboflavin to regenerate the stable neutral riboflavin radical and reset the catalytic cycle. However, the present study revealed that the final UQ reduction via reduced riboflavin makes an important contribution to Na+ translocation through a critical role of its side chain. Based on the results, we discuss the critical role of the UQ side chain in Na+ translocation.
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Affiliation(s)
- Moe Ishikawa
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Seina Kuroda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Shinpei Uno
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Nicole L Butler
- Department of Biological Science, Rensselaer Polytechnic Institute, Troy, NY 12180, United States
| | - Sara Foreman
- Department of Biological Science, Rensselaer Polytechnic Institute, Troy, NY 12180, United States
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Blanca Barquera
- Department of Biological Science, Rensselaer Polytechnic Institute, Troy, NY 12180, United States; Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, United States
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
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5
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Uno S, Masuya T, Zdorevskyi O, Ikunishi R, Shinzawa-Itoh K, Lasham J, Sharma V, Murai M, Miyoshi H. Diverse reaction behaviors of artificial ubiquinones in mitochondrial respiratory complex I. J Biol Chem 2022; 298:102075. [PMID: 35643318 PMCID: PMC9243180 DOI: 10.1016/j.jbc.2022.102075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/24/2022] Open
Abstract
The ubiquinone (UQ) reduction step catalyzed by NADH-UQ oxidoreductase (mitochondrial respiratory complex I) is key to triggering proton translocation across the inner mitochondrial membrane. Structural studies have identified a long, narrow, UQ-accessing tunnel within the enzyme. We previously demonstrated that synthetic oversized UQs, which are unlikely to transit this narrow tunnel, are catalytically reduced by native complex I embedded in submitochondrial particles but not by the isolated enzyme. To explain this contradiction, we hypothesized that access of oversized UQs to the reaction site is obstructed in the isolated enzyme because their access route is altered following detergent solubilization from the inner mitochondrial membrane. In the present study, we investigated this using two pairs of photoreactive UQs (pUQm-1/pUQp-1 and pUQm-2/pUQp-2), with each pair having the same chemical properties except for a ∼1.0 Å difference in side-chain widths. Despite this subtle difference, reduction of the wider pUQs by the isolated complex was significantly slower than of the narrower pUQs, but both were similarly reduced by the native enzyme. In addition, photoaffinity-labeling experiments using the four [125I]pUQs demonstrated that their side chains predominantly label the ND1 subunit with both enzymes but at different regions around the tunnel. Finally, we show that the suppressive effects of different types of inhibitors on the labeling significantly changed depending on [125I]pUQs used, indicating that [125I]pUQs and these inhibitors do not necessarily share a common binding cavity. Altogether, we conclude that the reaction behaviors of pUQs cannot be simply explained by the canonical UQ tunnel model.
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Affiliation(s)
- Shinpei Uno
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | | | - Ryo Ikunishi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Kyoko Shinzawa-Itoh
- Department of Life Science, Graduate School of Life Science, University of Hyogo, Hyogo, Japan
| | - Jonathan Lasham
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Vivek Sharma
- Department of Physics, University of Helsinki, Helsinki, Finland; Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Masatoshi Murai
- 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.
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6
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Grba DN, Blaza JN, Bridges HR, Agip ANA, Yin Z, Murai M, Miyoshi H, Hirst J. Cryo-electron microscopy reveals how acetogenins inhibit mitochondrial respiratory complex I. J Biol Chem 2022; 298:101602. [PMID: 35063503 PMCID: PMC8861642 DOI: 10.1016/j.jbc.2022.101602] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 12/22/2022] Open
Abstract
Mitochondrial complex I (NADH:ubiquinone oxidoreductase), a crucial enzyme in energy metabolism, captures the redox potential energy from NADH oxidation/ubiquinone reduction to create the proton motive force used to drive ATP synthesis in oxidative phosphorylation. High-resolution single-particle electron cryo-EM analyses have provided detailed structural knowledge of the catalytic machinery of complex I, but not of the molecular principles of its energy transduction mechanism. Although ubiquinone is considered to bind in a long channel at the interface of the membrane-embedded and hydrophilic domains, with channel residues likely involved in coupling substrate reduction to proton translocation, no structures with the channel fully occupied have yet been described. Here, we report the structure (determined by cryo-EM) of mouse complex I with a tight-binding natural product acetogenin inhibitor, which resembles the native substrate, bound along the full length of the expected ubiquinone-binding channel. Our structure reveals the mode of acetogenin binding and the molecular basis for structure-activity relationships within the acetogenin family. It also shows that acetogenins are such potent inhibitors because they are highly hydrophobic molecules that contain two specific hydrophilic moieties spaced to lock into two hydrophilic regions of the otherwise hydrophobic channel. The central hydrophilic section of the channel does not favor binding of the isoprenoid chain when the native substrate is fully bound but stabilizes the ubiquinone/ubiquinol headgroup as it transits to/from the active site. Therefore, the amphipathic nature of the channel supports both tight binding of the amphipathic inhibitor and rapid exchange of the ubiquinone/ubiquinol substrate and product.
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Affiliation(s)
- Daniel N Grba
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - James N Blaza
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Hannah R Bridges
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Ahmed-Noor A Agip
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Zhan Yin
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Masatoshi Murai
- 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
| | - Judy Hirst
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK.
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7
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Unten Y, Murai M, Sakai K, Asami Y, Yamamoto T, Masuya T, Miyoshi H. Natural tetramic acids elicit multiple inhibitory actions against mitochondrial machineries presiding over oxidative phosphorylation. Biosci Biotechnol Biochem 2021; 85:2368-2377. [PMID: 34625801 DOI: 10.1093/bbb/zbab176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/04/2021] [Indexed: 11/14/2022]
Abstract
The mitochondrial machineries presiding over ATP synthesis via oxidative phosphorylation are promising druggable targets. Fusaramin, a 3-acyl tetramic acid isolated from Fusarium concentricum FKI-7550, is an inhibitor of oxidative phosphorylation in Saccharomyces cerevisiae mitochondria, although its target has yet to be identified. Fusaramin significantly interfered with [3H]ADP uptake by yeast mitochondria at the concentration range inhibiting oxidative phosphorylation. A photoreactive fusaramin derivative (pFS-5) specifically labeled voltage-dependent anion channel 1 (VDAC1), which facilitates trafficking of ADP/ATP across the outer mitochondrial membrane. These results strongly suggest that the inhibition of oxidative phosphorylation by fusaramin is predominantly attributable to the impairment of VDAC1 functions. Fusaramin also inhibited FoF1-ATP synthase and ubiquinol-cytochrome c oxidoreductase (complex III) at concentrations higher than those required for the VDAC inhibition. Considering that other tetramic acid derivatives are reported to inhibit FoF1-ATP synthase and complex III, natural tetramic acids were found to elicit multiple inhibitory actions against mitochondrial machineries.
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Affiliation(s)
- Yufu Unten
- 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
| | | | - Yukihiro Asami
- Graduate School of Infection Control Sciences.,Ōmura Satoshi Memorial Institute, Kitasato University, Tokyo, Japan
| | - Takenori Yamamoto
- Division of Molecular Target and Gene Therapy Production, National Institute of Health Sciences, Kanagawa, 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
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8
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Sakai K, Unten Y, Kimishima A, Nonaka K, Chinen T, Sakai K, Usui T, Shiomi K, Iwatsuki M, Murai M, Miyoshi H, Asami Y, Ōmura S. Traminines A and B, produced by Fusarium concentricum, inhibit oxidative phosphorylation in Saccharomyces cerevisiae mitochondria. J Ind Microbiol Biotechnol 2021; 48:6338109. [PMID: 34343309 PMCID: PMC8788869 DOI: 10.1093/jimb/kuab051] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 07/29/2021] [Indexed: 11/13/2022]
Abstract
Two new tetramic acid derivatives, traminines A (1) and B (2), were isolated from a culture broth of Fusarium concentricum FKI-7550 by bioassay-guided fractionation using multidrug-sensitive Saccharomyces cerevisiae 12geneΔ0HSR-iERG6. The chemical structures of 1 and 2 were elucidated by NMR studies. Compounds 1 and 2 inhibited the growth of the multidrug-sensitive yeast strain on nonfermentable medium containing glycerol, but not on fermentable medium containing glucose. These results strongly suggest that they target mitochondrial machineries presiding over ATP production via oxidative phosphorylation. Throughout the assay monitoring overall ADP-uptake/ATP-release in yeast mitochondria, 1 and 2 were shown to inhibit one or more enzymes involving oxidative phosphorylation. Based on biochemical characterization, we found that the interference with oxidative phosphorylation by 1 is attributable to the dual inhibition of complex III and FoF1-ATPase, whereas that by 2 is solely due to the inhibition of complex III.
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Affiliation(s)
- Katsuyuki Sakai
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Yufu Unten
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Aoi Kimishima
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.,Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
| | - Kenichi Nonaka
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.,Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
| | - Takumi Chinen
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan
| | - Kazunari Sakai
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.,Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
| | - Takeo Usui
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan
| | - Kazuro Shiomi
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.,Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
| | - Masato Iwatsuki
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.,Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yukihiro Asami
- Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.,Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
| | - Satoshi Ōmura
- Ōmura Satoshi Memorial Institute, Kitasato University, 5-9-1, shirokane Minato-ku, Tokyo 108-8641, Japan
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9
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Masuya T, Uno S, Murai M, Miyoshi H. Pinpoint Dual Chemical Cross-Linking Explores the Structural Dynamics of the Ubiquinone Reaction Site in Mitochondrial Complex I. Biochemistry 2021; 60:813-824. [PMID: 33650850 DOI: 10.1021/acs.biochem.0c00991] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The ubiquinone reduction step in NADH-ubiquinone oxidoreductase (complex I) is the key to triggering proton translocation in its membrane part. Although the existence of a long and narrow quinone-access channel has been identified, it remains debatable whether the channel model can account for binding of various ligands (ubiquinones and inhibitors) to the enzyme. We previously proposed that the matrix-side interfacial region of the 49 kDa, ND1, PSST, and 39 kDa subunits, which is covered by a loop connecting transmembrane helices (TMHs) 1 and 2 of ND3, may be the area for entry of some bulky ligands into the quinone reaction cavity. However, this proposition lacks direct evidence that the cavity is accessible from the putative matrix-side region, which allows ligands to pass. To address this, we examined whether Cys39 of ND3 and Asp160 of 49 kDa can be specifically cross-linked by bifunctional cross-linkers (tetrazine-maleimide hybrid, named TMBC). On the basis of the structural models of complex I, such dual cross-linking is unexpected because ND3 Cys39 and 49 kDa Asp160 are located on the TMH1-2 loop and deep inside the channel, respectively, and hence, they are physically separated by peptide chains forming the channel wall. However, three TMBCs with different spacer lengths did cross-link the two residues, resulting in the formation of new cross-linked ND3/49 kDa subunits. Chemical modification of either ND3 Cys39 or 49 kDa Asp160 blocked the dual cross-linking, ensuring the specificity of the cross-linking. Altogether, this study provides direct evidence that the quinone reaction cavity is indeed accessible from the proposed matrix-side region covered by the ND3 TMH1-2 loop.
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Affiliation(s)
- Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Shinpei Uno
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
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10
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Masuya T, Sano Y, Tanaka H, Butler NL, Ito T, Tosaki T, Morgan JE, Murai M, Barquera B, Miyoshi H. Inhibitors of a Na +-pumping NADH-ubiquinone oxidoreductase play multiple roles to block enzyme function. J Biol Chem 2020; 295:12739-12754. [PMID: 32690607 DOI: 10.1074/jbc.ra120.014229] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/18/2020] [Indexed: 11/06/2022] Open
Abstract
The Na+-pumping NADH-ubiquinone (UQ) oxidoreductase (Na+-NQR) is present in the respiratory chain of many pathogenic bacteria and is thought to be a promising antibiotic target. Whereas many details of Na+-NQR structure and function are known, the mechanisms of action of potent inhibitors is not well-understood; elucidating the mechanisms would not only advance drug design strategies but might also provide insights on a terminal electron transfer from riboflavin to UQ. To this end, we performed photoaffinity labeling experiments using photoreactive derivatives of two known inhibitors, aurachin and korormicin, on isolated Vibrio cholerae Na+-NQR. The inhibitors labeled the cytoplasmic surface domain of the NqrB subunit including a protruding N-terminal stretch, which may be critical to regulate the UQ reaction in the adjacent NqrA subunit. The labeling was blocked by short-chain UQs such as ubiquinone-2. The photolabile group (2-aryl-5-carboxytetrazole (ACT)) of these inhibitors reacts with nucleophilic amino acids, so we tested mutations of nucleophilic residues in the labeled region of NqrB, such as Asp49 and Asp52 (to Ala), and observed moderate decreases in labeling yields, suggesting that these residues are involved in the interaction with ACT. We conclude that the inhibitors interfere with the UQ reaction in two ways: the first is blocking structural rearrangements at the cytoplasmic interface between NqrA and NqrB, and the second is the direct obstruction of UQ binding at this interfacial area. Unusual competitive behavior between the photoreactive inhibitors and various competitors corroborates our previous proposition that there may be two inhibitor binding sites in Na+-NQR.
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Affiliation(s)
- Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Yuki Sano
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Hinako Tanaka
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | | | | | - Tatsuhiko Tosaki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Joel E Morgan
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Blanca Barquera
- Department of Biological Science and.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
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11
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Tsuji A, Akao T, Masuya T, Murai M, Miyoshi H. IACS-010759, a potent inhibitor of glycolysis-deficient hypoxic tumor cells, inhibits mitochondrial respiratory complex I through a unique mechanism. J Biol Chem 2020; 295:7481-7491. [PMID: 32295842 PMCID: PMC7247293 DOI: 10.1074/jbc.ra120.013366] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/13/2020] [Indexed: 12/14/2022] Open
Abstract
The small molecule IACS-010759 has been reported to potently inhibit the proliferation of glycolysis-deficient hypoxic tumor cells by interfering with the functions of mitochondrial NADH-ubiquinone oxidoreductase (complex I) without exhibiting cytotoxicity at tolerated doses in normal cells. Considering the significant cytotoxicity of conventional quinone-site inhibitors of complex I, such as piericidin and acetogenin families, we hypothesized that the mechanism of action of IACS-010759 on complex I differs from that of other known quinone-site inhibitors. To test this possibility, here we investigated IACS-010759's mechanism in bovine heart submitochondrial particles. We found that IACS-010759, like known quinone-site inhibitors, suppresses chemical modification by the tosyl reagent AL1 of Asp160 in the 49-kDa subunit, located deep in the interior of a previously proposed quinone-access channel. However, contrary to the other inhibitors, IACS-010759 direction-dependently inhibited forward and reverse electron transfer and did not suppress binding of the quinazoline-type inhibitor [125I]AzQ to the N terminus of the 49-kDa subunit. Photoaffinity labeling experiments revealed that the photoreactive derivative [125I]IACS-010759-PD1 binds to the middle of the membrane subunit ND1 and that inhibitors that bind to the 49-kDa or PSST subunit cannot suppress the binding. We conclude that IACS-010759's binding location in complex I differs from that of any other known inhibitor of the enzyme. Our findings, along with those from previous study, reveal that the mechanisms of action of complex I inhibitors with widely different chemical properties are more diverse than can be accounted for by the quinone-access channel model proposed by structural biology studies.
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Affiliation(s)
- Atsuhito Tsuji
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Takumi Akao
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
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Abstract
NADH-quinone oxidoreductase (respiratory complex I) is a key player in mitochondrial energy metabolism. The enzyme couples electron transfer from NADH to quinone with the translocation of protons across the membrane, providing a major proton-motive force that drives ATP synthesis. Recently, X-ray crystallography and cryo-electron microscopy provided further insights into the structure and functions of the enzyme. However, little is known about the mechanism of quinone reduction, which is a crucial step in the energy coupling process. A variety of complex I inhibitors targeting the quinone-binding site have been indispensable tools for mechanistic studies on the enzyme. Using biorationally designed inhibitor probes, the author has accumulated a large amount of experimental data characterizing the actions of complex I inhibitors. On the basis of comprehensive interpretations of the data, the author reviews the structural features of the binding pocket of quinone/inhibitors in bovine mitochondrial complex I. ABBREVIATIONS ATP: adenosine triphosphate; BODIPY: boron dipyrromethene; complex I: proton-translocating NADH-quinone oxidoreductase; DIBO: dibenzocyclooctyne; EM: electron microscopy; FeS: iron-sulfur; FMN: flavin adenine mononucleotide; LDT: ligand-directed tosylate; NADH: nicotinamide adenine dinucleotide; ROS: reactive oxygen species; SMP: submitochondrial particle; TAMRA: 6-carboxy-N,N,N',N'-tetramethylrhodamine; THF: tetrahydrofuran; TMH: transmembrane helix.
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Affiliation(s)
- Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Kyoto, Japan
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Uno S, Masuya T, Shinzawa-Itoh K, Lasham J, Haapanen O, Shiba T, Inaoka DK, Sharma V, Murai M, Miyoshi H. Oversized ubiquinones as molecular probes for structural dynamics of the ubiquinone reaction site in mitochondrial respiratory complex I. J Biol Chem 2020; 295:2449-2463. [PMID: 31953326 DOI: 10.1074/jbc.ra119.012347] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/15/2020] [Indexed: 12/18/2022] Open
Abstract
NADH-quinone oxidoreductase (complex I) couples electron transfer from NADH to quinone with proton translocation across the membrane. Quinone reduction is a key step for energy transmission from the site of quinone reduction to the remotely located proton-pumping machinery of the enzyme. Although structural biology studies have proposed the existence of a long and narrow quinone-access channel, the physiological relevance of this channel remains debatable. We investigated here whether complex I in bovine heart submitochondrial particles (SMPs) can catalytically reduce a series of oversized ubiquinones (OS-UQs), which are highly unlikely to transit the narrow channel because their side chain includes a bulky "block" that is ∼13 Å across. We found that some OS-UQs function as efficient electron acceptors from complex I, accepting electrons with an efficiency comparable with ubiquinone-2. The catalytic reduction and proton translocation coupled with this reduction were completely inhibited by different quinone-site inhibitors, indicating that the reduction of OS-UQs takes place at the physiological reaction site for ubiquinone. Notably, the proton-translocating efficiencies of OS-UQs significantly varied depending on their side-chain structures, suggesting that the reaction characteristics of OS-UQs affect the predicted structural changes of the quinone reaction site required for triggering proton translocation. These results are difficult to reconcile with the current channel model; rather, the access path for ubiquinone may be open to allow OS-UQs to access the reaction site. Nevertheless, contrary to the observations in SMPs, OS-UQs were not catalytically reduced by isolated complex I reconstituted into liposomes. We discuss possible reasons for these contradictory results.
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Affiliation(s)
- Shinpei Uno
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Takahiro Masuya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Kyoko Shinzawa-Itoh
- Department of Life Science, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan
| | - Jonathan Lasham
- Department of Physics, University of Helsinki, FI-00014 Helsinki, Finland
| | - Outi Haapanen
- Department of Physics, University of Helsinki, FI-00014 Helsinki, Finland
| | - Tomoo Shiba
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Kyoto 606-8585, Japan
| | - Daniel Ken Inaoka
- Department of Molecular Infection Dynamics, Institute of Tropical Medicine (NEKKEN); School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki 852-8523, Japan
| | - Vivek Sharma
- Department of Physics, University of Helsinki, FI-00014 Helsinki, Finland; Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
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Murai M, Miyoshi H. Photoaffinity Labeling of Respiratory Complex I in Bovine Heart Submitochondrial Particles by Photoreactive [ 125I] amilorides. Bio Protoc 2019; 9:e3349. [PMID: 33654851 DOI: 10.21769/bioprotoc.3349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/26/2019] [Accepted: 07/28/2019] [Indexed: 12/12/2022] Open
Abstract
The architecture of quinone/inhibitor-access channel in proton-translocating NADH-quinone oxidoreductase (respiratory complex I) was modeled by X-ray crystallography and cryo-EM, however, it remains debatable whether the channel model reflects the physiologically relevant state present throughout the catalytic cycle. Using photoreactive [125I]amilorides, we demonstrated that amiloride-type inhibitors bind to the interfacial region of multiple subunits (49-kDa, ND1, PSST, and 39-kDa subunits), which is difficult to reconcile with the current channel model. This report describes the procedures for photoaffinity labeling of bovine submitochondrial particles by photoreactive [125I]amilorides. The protocol could be widely applicable for the characterization of various biologically active compounds, whose target protein remains to be identified or characterized.
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Affiliation(s)
- Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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15
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Sakai K, Unten Y, Iwatsuki M, Matsuo H, Fukasawa W, Hirose T, Chinen T, Nonaka K, Nakashima T, Sunazuka T, Usui T, Murai M, Miyoshi H, Asami Y, Ōmura S, Shiomi K. Fusaramin, an antimitochondrial compound produced by Fusarium sp., discovered using multidrug-sensitive Saccharomyces cerevisiae. J Antibiot (Tokyo) 2019; 72:645-652. [DOI: 10.1038/s41429-019-0197-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/07/2019] [Accepted: 05/13/2019] [Indexed: 12/11/2022]
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Maynard A, Butler NL, Ito T, da Silva AJ, Murai M, Chen T, Koffas MAG, Miyoshi H, Barquera B. Antibiotic Korormicin A Kills Bacteria by Producing Reactive Oxygen Species. J Bacteriol 2019; 201:e00718-18. [PMID: 30858300 PMCID: PMC6509656 DOI: 10.1128/jb.00718-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 03/07/2019] [Indexed: 11/20/2022] Open
Abstract
Korormicin is an antibiotic produced by some pseudoalteromonads which selectively kills Gram-negative bacteria that express the Na+-pumping NADH:quinone oxidoreductase (Na+-NQR.) We show that although korormicin is an inhibitor of Na+-NQR, the antibiotic action is not a direct result of inhibiting enzyme activity. Instead, perturbation of electron transfer inside the enzyme promotes a reaction between O2 and one or more redox cofactors in the enzyme (likely the flavin adenine dinucleotide [FAD] and 2Fe-2S center), leading to the production of reactive oxygen species (ROS). All Pseudoalteromonas contain the nqr operon in their genomes, including Pseudoalteromonas strain J010, which produces korormicin. We present activity data indicating that this strain expresses an active Na+-NQR and that this enzyme is not susceptible to korormicin inhibition. On the basis of our DNA sequence data, we show that the Na+-NQR of Pseudoalteromonas J010 carries an amino acid substitution (NqrB-G141A; Vibrio cholerae numbering) that in other Na+-NQRs confers resistance against korormicin. This is likely the reason that a functional Na+-NQR is able to exist in a bacterium that produces a compound that typically inhibits this enzyme and causes cell death. Korormicin is an effective antibiotic against such pathogens as Vibrio cholerae, Aliivibrio fischeri, and Pseudomonas aeruginosa but has no effect on Bacteroides fragilis and Bacteroides thetaiotaomicron, microorganisms that are important members of the human intestinal microflora.IMPORTANCE As multidrug antibiotic resistance in pathogenic bacteria continues to rise, there is a critical need for novel antimicrobial agents. An essential requirement for a useful antibiotic is that it selectively targets bacteria without significant effects on the eukaryotic hosts. Korormicin is an excellent candidate in this respect because it targets a unique respiratory enzyme found only in prokaryotes, the Na+-pumping NADH:quinone oxidoreductase (Na+-NQR). Korormicin is synthesized by some species of the marine bacterium Pseudoalteromonas and is a potent and specific inhibitor of Na+-NQR, an enzyme that is essential for the survival and proliferation of many Gram-negative human pathogens, including Vibrio cholerae and Pseudomonas aeruginosa, among others. Here, we identified how korormicin selectively kills these bacteria. The binding of korormicin to Na+-NQR promotes the formation of reactive oxygen species generated by the reaction of the FAD and the 2Fe-2S center cofactors with O2.
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Affiliation(s)
- Adam Maynard
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Nicole L Butler
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York, USA
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Takeshi Ito
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Adilson José da Silva
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
- Chemical Engineering Department, Federal University of Sao Carlos, Sao Paulo, Brazil
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Tsute Chen
- The Forsyth Institute, Cambridge, Massachusetts, USA
- School of Dental Medicine, Harvard University, Boston, Massachusetts, USA
| | - Mattheos A G Koffas
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Blanca Barquera
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York, USA
- Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, USA
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Banba A, Tsuji A, Kimura H, Murai M, Miyoshi H. Defining the mechanism of action of S1QELs, specific suppressors of superoxide production in the quinone-reaction site in mitochondrial complex I. J Biol Chem 2019; 294:6550-6561. [PMID: 30824536 DOI: 10.1074/jbc.ra119.007687] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/25/2019] [Indexed: 12/21/2022] Open
Abstract
Site-specific suppressors of superoxide production (named S1QELs) in the quinone-reaction site in mitochondrial respiratory complex I during reverse electron transfer have been previously reported; however, their mechanism of action remains elusive. Using bovine heart submitochondrial particles, we herein investigated the effects of S1QELs on complex I functions. We found that the inhibitory effects of S1QELs on complex I are distinctly different from those of other known quinone-site inhibitors. For example, the inhibitory potencies of S1QELs significantly varied depending on the direction of electron transfer (forward or reverse). S1QELs marginally suppressed the specific chemical modification of Asp160 in the 49-kDa subunit, located deep in the quinone-binding pocket, by the tosyl chemistry reagent AL1. S1QELs also failed to suppress the binding of a photoreactive quinazoline-type inhibitor ([125I]AzQ) to the 49-kDa subunit. Moreover, a photoaffinity labeling experiment with photoreactive S1QEL derivatives indicated that they bind to a segment in the ND1 subunit that is not considered to make up the binding pocket for quinone or inhibitors. These results indicate that unlike known quinone-site inhibitors, S1QELs do not occupy the quinone- or inhibitor-binding pocket; rather, they may indirectly modulate the quinone-redox reactions by inducing structural changes of the pocket through binding to ND1. We conclude that this indirect effect may be a prerequisite for S1QELs' direction-dependent modulation of electron transfer. This, in turn, may be responsible for the suppression of superoxide production during reverse electron transfer without significantly interfering with forward electron transfer.
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Affiliation(s)
- Atsushi Banba
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Atsuhito Tsuji
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hironori Kimura
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Ochi T, Giampaolo B, Murai M, Nozaki F, Kobayashi D, Iwamoto T, Niikura N, Suzuki K, Yamauchi H, Hayashi N. Abstract P2-08-31: Predictive and prognostic value of stromal tumor-infiltrating lymphocytes before and after neoadjuvant therapy in triple negative and HER2-positive breast cancer. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p2-08-31] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Lymphocyte predominant breast cancer subgroup, defined as ≥ 50% stromal tumor-infiltrating lymphocytes (sTILs), is associated with high pathological complete response (pCR) rate after neoadjuvant therapy (NAT) and favorable outcome. In a cohort of triple negative (TNBC) and HER2+ breast cancer (BC) patients treated with NAT, we aimed to assess the predictive and prognostic value of pre- and post-NAT sTILs and the information provided by the change in sTILs during NAT.
Materials and methods: Two-hundred and nine consecutive patients (n=80 TNBC; and n=129 HER2+) who received NAT between 2001 and 2009 in our institution were evaluated. Pre-NAT sTILs were assessed on biopsy sample (baseline) and post-NAT sTILs on surgical specimens just for non-pCR patients. sTILs level was categorized as low 0-9%, intermediate 10-49%, and high ≥50%. The change in sTILs during NAT was calculated as the absolute difference between pre- and post-NAT sTILs. We evaluated the association of pre-NAT sTILs and pCR, and the association between pre- and post-NAT sTILs, and their change with relapse-free survival (RFS).
Results: Overall pCR rate was 37.8% (31.3% for TNBC, 41.2% for ER+/HER2+BC, 42.3% for ER-/HER2+BC). In each subtype, pre-NAT low sTILs group was significantly associated with lower pCR rate. During the median follow-up period of 98 months, 44 recurrences (21.1%) were observed. For TNBC, low pre-NAT sTILs group was associated with higher recurrence risk compared with int/high sTILs (HR=4.675 [2.013-10.859], p<0.001). For only non-pCR patients, both pre- and post-NAT sTILs were significantly associated with RFS. The risk of recurrence was higher in the group with low pre-NAT sTILs (HR=5.333 [1.731-16.427], p=0.004), and the group of low post-NAT sTILs (HR=4.271 [1.498-12.173], p=0.007). Patients with the change of sTILs increase during NAT were not associated with RFS, compared with decrease or equal group (log-rank p=0.163). In multivariate analysis including both pre- and post-NAT sTILs, only pre-NAT sTILs retained significance (HR=3.844 [1.190-12.421], p=0.024). Low post-NAT sTILs group showed only a borderline significant association with shorter RFS (HR=2.836 [0.951-8.457], p=0.061), but it suggests that both pre- and post-NAT sTILs might provide independent prognostic information. In ER+/HER2+BC, low pre-NAT sTILs were associated with short RFS (p=0.036), but this association was not significant when only non-pCR patients were considered. In ER−/HER2+BC, sTILs were not significantly associated with RFS.
Conclusion: In TN and HER2+ BCs, tumors with low pre-NAT sTILs have a low likelihood to achieve a pCR (predictive marker). In TNBC, low pre-NAT sTILs were associated with higher recurrence risk. In non-pCR TNBC patients, both low pre- and post-NAT sTILs were associated with shorter RFS. These results suggest that sTILs information should be taken into account when additional post-surgery treatments are considered in non-pCR patients.
Citation Format: Ochi T, Giampaolo B, Murai M, Nozaki F, Kobayashi D, Iwamoto T, Niikura N, Suzuki K, Yamauchi H, Hayashi N. Predictive and prognostic value of stromal tumor-infiltrating lymphocytes before and after neoadjuvant therapy in triple negative and HER2-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-31.
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Affiliation(s)
- T Ochi
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - B Giampaolo
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - M Murai
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - F Nozaki
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - D Kobayashi
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - T Iwamoto
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - N Niikura
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - K Suzuki
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - H Yamauchi
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
| | - N Hayashi
- St. Luke's International Hospital, Tokyo, Japan; San Raffaele Scientific Institute, Milan, Italy; Okayama University Hospital, Okayama, Japan; Tokai University School of Medicine, Isehara, Japan
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Unten Y, Murai M, Yamamoto T, Watanabe A, Ichimaru N, Aburaya S, Aoki W, Shinohara Y, Miyoshi H. Pentenediol-Type Compounds Specifically Bind to Voltage-Dependent Anion Channel 1 in Saccharomyces cerevisiae Mitochondria. Biochemistry 2019; 58:1141-1154. [PMID: 30657320 DOI: 10.1021/acs.biochem.8b01209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Voltage-dependent anion channel 1 (VDAC1) situated in the outer mitochondrial membrane regulates the transfer of various metabolites and is a key player in mitochondria-mediated apoptosis. Although many small chemicals that modulate the functions of VDAC1 have been reported to date, most, if not all, of them cannot be regarded as specific reagents due to their interactions with other transporters or enzymes. By screening our chemical libraries using isolated Saccharomyces cerevisiae mitochondria, we found pentenediol (PTD)-type compounds (e.g., PTD-023) as new specific inhibitors of VDAC1. PTD-023 inhibited overall ADP-uptake/ATP-release reactions in isolated mitochondria at a single digit μM level. To identify the binding position of PTDs in VDAC1 by visualizing PTD-bound peptides, we conducted ligand-directed tosyl (LDT) chemistry using the synthetic LDT reagent t-PTD-023 derived from the parent PTD-023 in combination with mutagenesis experiments. t-PTD-023 made a covalent bond predominantly and subsidiarily with nucleophilic Cys210 and Cys130, respectively, indicating that PTDs bind to the region interactive with both residues. Site-directed mutations of hydrogen bond-acceptable Asp139 and Glu152 to Ala, which were selected as potential interactive partners of the critical pentenediol moiety based on the presumed binding model of PTDs in VDAC1, resulted in a decrease in susceptibility against PTD-023. This result strongly suggests that PTDs bind to VDAC1 through a specific hydrogen bond with the two residues. The present study is the first to demonstrate the binding position of specific inhibitors of VDAC1 at the amino acid level.
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Affiliation(s)
- Yufu Unten
- Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto 606-8502 , Japan
| | - Masatoshi Murai
- 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
| | - Akira Watanabe
- Institute for Genome Research , University of Tokushima , Kuramotocho-3 , Tokushima 770-8503 , Japan
| | - Naoya Ichimaru
- Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto 606-8502 , Japan
| | - Shunsuke Aburaya
- Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto 606-8502 , Japan
| | - Wataru Aoki
- Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto 606-8502 , 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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Uno S, Kimura H, Murai M, Miyoshi H. Exploring the quinone/inhibitor-binding pocket in mitochondrial respiratory complex I by chemical biology approaches. J Biol Chem 2018; 294:679-696. [PMID: 30425100 DOI: 10.1074/jbc.ra118.006056] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/10/2018] [Indexed: 11/06/2022] Open
Abstract
NADH-quinone oxidoreductase (respiratory complex I) couples NADH-to-quinone electron transfer to the translocation of protons across the membrane. Even though the architecture of the quinone-access channel in the enzyme has been modeled by X-ray crystallography and cryo-EM, conflicting findings raise the question whether the models fully reflect physiologically relevant states present throughout the catalytic cycle. To gain further insights into the structural features of the binding pocket for quinone/inhibitor, we performed chemical biology experiments using bovine heart sub-mitochondrial particles. We synthesized ubiquinones that are oversized (SF-UQs) or lipid-like (PC-UQs) and are highly unlikely to enter and transit the predicted narrow channel. We found that SF-UQs and PC-UQs can be catalytically reduced by complex I, albeit only at moderate or low rates. Moreover, quinone-site inhibitors completely blocked the catalytic reduction and the membrane potential formation coupled to this reduction. Photoaffinity-labeling experiments revealed that amiloride-type inhibitors bind to the interfacial domain of multiple core subunits (49 kDa, ND1, and PSST) and the 39-kDa supernumerary subunit, although the latter does not make up the channel cavity in the current models. The binding of amilorides to the multiple target subunits was remarkably suppressed by other quinone-site inhibitors and SF-UQs. Taken together, the present results are difficult to reconcile with the current channel models. On the basis of comprehensive interpretations of the present results and of previous findings, we discuss the physiological relevance of these models.
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Affiliation(s)
- Shinpei Uno
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hironori Kimura
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- From the Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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21
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Katsura N, Higashiguchi T, Murai M, Oohara H, Yamashita M. The preliminary trial to have the new predictor of cancer pain with sarcopenia. Clin Nutr 2018. [DOI: 10.1016/j.clnu.2018.06.1716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Aoyama A, Murai M, Ichimaru N, Aburaya S, Aoki W, Miyoshi H. Epoxycyclohexenedione-Type Compounds Make Up a New Class of Inhibitors of the Bovine Mitochondrial ADP/ATP Carrier. Biochemistry 2018; 57:1031-1044. [PMID: 29313673 DOI: 10.1021/acs.biochem.7b01119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Through the extensive screening of our chemical library, we found epoxycyclohexenedione (ECHD)-type compounds (AMM-59 and -120) as unique inhibitors of the bovine heart mitochondrial ADP/ATP carrier (AAC). This study investigated the mechanism of inhibition of AAC by ECHDs using submitochondrial particles (SMPs). Proteomic analyses of ECHD-bound AAC as well as biochemical characterization using different SH reagents showed that ECHDs inhibit the function of AAC by covalently binding primarily to Cys57 and secondarily to Cys160. Interestingly, AAC remarkably aggregated in SMPs upon being incubated with high concentrations of ECHDs for a long period of time. This aggregation was observed under both oxidative and reductive conditions of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of SMP proteins, indicating that aggregation is not caused by intermolecular S-S linkages. ECHDs are the first chemicals, to the best of our knowledge, to induce prominent structural alteration in AAC without forming intermolecular S-S linkages. When all solvent-accessible cysteines (Cys57, Cys160, and Cys257) were previously modified by N-ethylmaleimide, the aggregation of AAC was completely suppressed. In contrast, when Cys57 or Cys160 is selectively modified by a SH reagent, the covalent binding of ECHDs to a residual free residue of the two cysteines is sufficient to induce aggregation. The aggregation-inducing ability of another ECHD analogue (AMM-124), which has an alkyl chain that is shorter than those of AMM-59 and -120, was significantly less efficient than that of the two compounds. On the basis of these results, the mechanism underlying the aggregation of AAC induced by ECHDs is discussed.
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Affiliation(s)
- Ayaki Aoyama
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Naoya Ichimaru
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Shunsuke Aburaya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Wataru Aoki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
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23
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Masuya T, Murai M, Ito T, Aburaya S, Aoki W, Miyoshi H. Pinpoint Chemical Modification of the Quinone-Access Channel of Mitochondrial Complex I via a Two-Step Conjugation Reaction. Biochemistry 2017; 56:4279-4287. [DOI: 10.1021/acs.biochem.7b00612] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Takahiro Masuya
- Division of Applied
Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied
Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Takeshi Ito
- Division of Applied
Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Shunsuke Aburaya
- Division of Applied
Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Wataru Aoki
- Division of Applied
Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied
Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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24
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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25
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Sasaki Y, Kikuchi A, Murai M, Kanasugi T, Isurugi C, Oyama R, Sugiyama T. Fetal goiter associated with preconception hysterosalpingography using an oil-soluble iodinated contrast medium. Ultrasound Obstet Gynecol 2017; 49:275-276. [PMID: 26935488 DOI: 10.1002/uog.15902] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 02/18/2016] [Accepted: 02/26/2016] [Indexed: 06/05/2023]
Affiliation(s)
- Y Sasaki
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
| | - A Kikuchi
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
| | - M Murai
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
| | - T Kanasugi
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
| | - C Isurugi
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
| | - R Oyama
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
| | - T Sugiyama
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate, 020-8505, Japan
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26
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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27
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Mori N, Higashiguchi T, Ito A, Murai M, Ohara H, Tsuzuki N, Nakagawa A, Awa H, Miyoshi A, Akihiko F, Uekuzu Y. PT08.1: Pinch Grip Strength is a Simple Indicator for Prognosis and Muscle Depletion in Patients with Far Advanced Cancer. Clin Nutr 2016. [DOI: 10.1016/s0261-5614(16)30326-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Chida H, Kikuchi A, Murai M, Sasaki Y, Kanasugi T, Isurugi C, Oyama R, Sugiyama T. Intramural Pregnancy Implanted Into a Myometrial Defect Caused by Curettage: Diagnosis With Transvaginal Sonography and Preconception and Postconception Magnetic Resonance Imaging. J Ultrasound Med 2016; 35:2066-2067. [PMID: 27574126 DOI: 10.7863/ultra.15.11071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Hideyuki Chida
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Akihiko Kikuchi
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Masatoshi Murai
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Yuri Sasaki
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Tomonobu Kanasugi
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Chizuko Isurugi
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Rie Oyama
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
| | - Toru Sugiyama
- Department of Obstetrics and Gynecology Iwate Medical University School of Medicine Morioka, Japan
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Abstract
The dissolution time of rigid polyurethane foam (PUF) under various glycolysis conditions was examined in a detailed investigation of the glycolysis reactivity of PUF. PUF dissolution depended on the molecular weight of glycol. Dipropylene glycol and tetraethylene glycol dissolved PUF in the shortest time among polypropylene glycols and polyethylene glycols, respectively. PUF dissolution time was reduced to one-half for each 10 C rise in the range of 170–200 C. Also PUF dissolution time was inverselyproportional to KOH (catalyst) concentration. Dibutyltindilaurate concentration had less influence on PUF dissolution time than KOH concentration. Smaller PUF particles dissolved in a shorter time. Especially, the initial glycolysis conversion of PUF was proportional to the total surface area of PUF particles.
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Affiliation(s)
- M. Murai
- Advanced Technology R&D Center, Mitsubishi Electric Corporation, 8-1-1, Tsukaguchi-Honmachi, Amagasaki-City, Hyogo, 661-8661, Japan
| | | | | | - F. Baba
- Advanced Technology R&D Center, Mitsubishi Electric Corporation, 8-1-1, Tsukaguchi-Honmachi, Amagasaki-City, Hyogo, 661-8661, Japan
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30
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Murai M, Inaoka H, Masuya T, Aburaya S, Aoki W, Miyoshi H. Specific Methylation of Asp160 (49 kDa subunit) Located inside the Quinone Binding Cavity of Bovine Mitochondrial Complex I. Biochemistry 2016; 55:3189-97. [DOI: 10.1021/acs.biochem.6b00190] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Masatoshi Murai
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hiroyuki Inaoka
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Takahiro Masuya
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Shunsuke Aburaya
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Wataru Aoki
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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31
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Masuya T, Okuda K, Murai M, Miyoshi H. Characterization of the reaction of decoupling ubiquinone with bovine mitochondrial respiratory complex I. Biosci Biotechnol Biochem 2016; 80:1464-9. [PMID: 27140857 DOI: 10.1080/09168451.2016.1179095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We previously produced the unique ubiquinone QT ("decoupling" quinone), the catalytic reduction of which in NADH-quinone oxidoreduction with bovine heart mitochondrial NADH-ubiquinone oxidoreductase (complex I) is completely decoupled from proton translocation across the membrane domain. This feature is markedly distinct from those of typical short-chain quinones such as ubiquinone-1. To further characterize the features of the QT reaction with complex I, we herein synthesized three QT analogs, QT2-QT4, and characterized their electron transfer reactions. We found that all aspects of electron transfer (e.g. electron-accepting activity and membrane potential formation) vary significantly among these analogs. The features of QT2 as decoupling quinone were slightly superior to those of original QT. Based on these results, we conclude that the bound positions of QTs within the quinone binding cavity susceptibly change depending on their side-chain structures, and the positions, in turn, govern the behavior of QTs as electron acceptors.
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Affiliation(s)
- Takahiro Masuya
- a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto , Japan
| | - Kenji Okuda
- a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto , Japan
| | - Masatoshi Murai
- a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto , Japan
| | - Hideto Miyoshi
- a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Sakyo-ku, Kyoto , Japan
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32
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Kanasugi T, Kikuchi A, Murai M, Sasaki Y, Isurugi C, Oyama R, Sugiyama T. Successful ultrasound-guided intraoperative external cephalic version of fetus in breech presentation immediately before ex-utero intrapartum treatment (EXIT) procedure. Ultrasound Obstet Gynecol 2016; 47:653-655. [PMID: 26411591 DOI: 10.1002/uog.15763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 09/14/2015] [Accepted: 09/18/2015] [Indexed: 06/05/2023]
Affiliation(s)
- T Kanasugi
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
| | - A Kikuchi
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
| | - M Murai
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
| | - Y Sasaki
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
| | - C Isurugi
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
| | - R Oyama
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
| | - T Sugiyama
- Department of Obstetrics and Gynecology, Iwate Medical University School of Medicine, 19-1 Uchimaru, Morioka, Iwate 020-8505, Japan
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33
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Suga T, Asami Y, Hashimoto S, Nonaka K, Iwatsuki M, Nakashima T, Watanabe Y, Sugahara R, Shiotsuki T, Yamamoto T, Shinohara Y, Ichimaru N, Murai M, Miyoshi H, Ōmura S, Shiomi K. Trichopolyn VI: a new peptaibol insecticidal compound discovered using a recombinant Saccharomyces cerevisiae screening system. J GEN APPL MICROBIOL 2016; 61:82-7. [PMID: 26227911 DOI: 10.2323/jgam.61.82] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In the course of searching for insecticides from soil microorganisms, we found that a fermentation broth of the fungus, Trichoderma brevicompactum FKI-6324, produced Trichopolyn VI, a new peptaibol, which possessed significant insecticidal potential. Spectroscopic analysis showed the compound to be a new trichopolyn I derivative. This paper describes the isolation, structure elucidation and biological activity of trichopolyn VI.
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Affiliation(s)
- Takuya Suga
- Graduate School of Infection Control Sciences, Kitasato University
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34
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Okuda K, Murai M, Aburaya S, Aoki W, Miyoshi H. Reduction of Synthetic Ubiquinone QT Catalyzed by Bovine Mitochondrial Complex I Is Decoupled from Proton Translocation. Biochemistry 2016; 55:470-81. [PMID: 26701224 DOI: 10.1021/acs.biochem.5b01090] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We previously succeeded in site-specific chemical modifications of the inner part of the quinone binding pocket of bovine mitochondrial complex I through ligand-directed tosylate (LDT) chemistry using specific inhibitors as high-affinity ligands for the enzyme [Masuya, T., et al. (2014) Biochemistry 53, 2304-2317, 7816-7823]. To investigate whether a short-chain ubiquinone, in place of these specific inhibitors, serves as a ligand for LDT chemistry, we herein synthesized a LDT reagent QT possessing ubiquinone scaffold and performed LDT chemistry with bovine heart submitochondrial particles (SMP). Detailed proteomic analyses revealed that QT properly guides the tosylate group into the quinone binding pocket and transfers a terminal alkyne to nucleophilic amino acids His150 and Asp160 in the 49 kDa subunit. This result clearly indicates that QT occupies the inner part of the quinone binding pocket. Nevertheless, we noted that QT is a unique electron acceptor from complex I distinct from typical short-chain ubiquinones such as ubiquinone-1 (Q1) for several reasons; for example, QT reduction in NADH-QT oxidoreduction was almost completely insensitive to quinone-site inhibitors (such as bullatacin and piericidin A), and this reaction did not produce a membrane potential. On the basis of detailed comparisons of the electron transfer features between QT and typical short-chain quinones, we conclude that QT may accept electrons from an N2 cluster at a position different from that of typical short-chain quinones because of its unique side-chain structure; accordingly, QT reduction is unable to induce putative structural changes inside the quinone binding pocket, which are critical for driving proton translocation. Thus, QT is the first ubiquinone analogue, to the best of our knowledge, the catalytic reduction of which is decoupled from proton translocation through the membrane domain. Implications for mechanistic studies on QT are also discussed.
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Affiliation(s)
- Kenji Okuda
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Shunsuke Aburaya
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Wataru Aoki
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University , Sakyo-ku, Kyoto 606-8502, Japan
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35
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Ito T, Murai M, Morisaka H, Miyoshi H. Identification of the Binding Position of Amilorides in the Quinone Binding Pocket of Mitochondrial Complex I. Biochemistry 2015; 54:3677-86. [PMID: 26009789 DOI: 10.1021/acs.biochem.5b00385] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We previously demonstrated that amilorides bind to the quinone binding pocket of bovine mitochondrial complex I, not to the hitherto suspected Na⁺/H⁺ antiporter-like subunits (ND2, ND4, and ND5) [Murai, M., et al. (2015) Biochemistry 54, 2739-2746]. To characterize the binding position of amilorides within the pocket in more detail, we conducted specific chemical labeling [alkynylation (-C≡CH)] of complex I via ligand-directed tosyl (LDT) chemistry using a newly synthesized amide-type amiloride AAT as a LDT chemistry reagent. The inhibitory potency of AAT, in terms of its IC50 value, was markedly higher (∼1000-fold) than that of prototypical guanidine-type amilorides such as commercially available EIPA and benzamil. Detailed proteomic analyses in combination with click chemistry revealed that the chemical labeling occurred at Asp160 of the 49 kDa subunit (49 kDa Asp160). This labeling was significantly suppressed in the presence of an excess amount of other amilorides or ordinary inhibitors such as quinazoline and acetogenin. Taking into consideration the fact that 49 kDa Asp160 was also specifically labeled by LDT chemistry reagents derived from acetogenin [Masuya, T., et al. (2014) Biochemistry 53, 2307-2317, 7816-7823], we found this aspartic acid to elicit very strong nucleophilicity in the local protein environment. The structural features of the quinone binding pocket in bovine complex I are discussed on the basis of this finding.
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Affiliation(s)
- Takeshi Ito
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hironobu Morisaka
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Suga T, Asami Y, Hashimoto S, Nonaka K, Iwatsuki M, Nakashima T, Sugahara R, Shiotsuki T, Yamamoto T, Shinohara Y, Ichimaru N, Murai M, Miyoshi H, Ōmura S, Shiomi K. Ascosteroside C, a new mitochondrial respiration inhibitor discovered by pesticidal screening using recombinant Saccharomyces cerevisiae. J Antibiot (Tokyo) 2015; 68:649-52. [PMID: 25944534 DOI: 10.1038/ja.2015.43] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/27/2015] [Accepted: 03/31/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Takuya Suga
- Department of Drug Discovery Sciences, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan
| | - Yukihiro Asami
- Department of Drug Discovery Sciences, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.,Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
| | - Shohei Hashimoto
- Department of Chemistry, School of Science, Kitasato University, Kanagawa, Japan
| | - Kenichi Nonaka
- Department of Drug Discovery Sciences, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.,Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
| | - Masato Iwatsuki
- Department of Drug Discovery Sciences, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.,Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
| | - Takuji Nakashima
- Research Organization for Infection Control Sciences, Kitasato University, Tokyo, Japan
| | - Ryohei Sugahara
- Insect Growth Regulation Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Takahiro Shiotsuki
- Insect Growth Regulation Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Takenori Yamamoto
- Institute for Genome Research, University of Tokushima, Tokushima, Japan
| | - Yasuo Shinohara
- Institute for Genome Research, University of Tokushima, Tokushima, Japan.,Faculty of Pharmaceutical Sciences, University of Tokushima, Tokushima, Japan
| | - Naoya Ichimaru
- 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
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Satoshi Ōmura
- Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
| | - Kazuro Shiomi
- Department of Drug Discovery Sciences, Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan.,Kitasato Institute for Life Sciences, Kitasato University, Tokyo, Japan
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Taniguchi Y, Takahashi Y, Toba T, Yamada S, Yokoi K, Kobayashi S, Okajima S, Shimane A, Kawai H, Yasaka Y, Smanio P, Oliveira MA, Machado L, Cestari P, Medeiros E, Fukuzawa S, Okino S, Ikeda A, Maekawa J, Ichikawa S, Kuroiwa N, Yamanaka K, Igarashi A, Inagaki M, Patel K, Mahan M, Ananthasubramaniam K, Mouden M, Yokota S, Ottervanger J, Knollema S, Timmer J, Jager P, Padron K, Peix A, Cabrera L, Pena Bofill V, Valera D, Rodriguez Nande L, Carrillo Hernandez R, Mena Esnard E, Fernandez Columbie Y, Bertella E, Baggiano A, Mushtaq S, Segurini C, Loguercio M, Conte E, Beltrama V, Petulla' M, Andreini D, Pontone G, Guzic Salobir B, Dolenc Novak M, Jug B, Kacjan B, Novak Z, Vrtovec M, Mushtaq S, Pontone G, Bertella E, Conte E, Segurini C, Volpato V, Baggiano A, Formenti A, Pepi M, Andreini D, Ajanovic R, Husic-Selimovic A, Zujovic-Ajanovic A, Mlynarski R, Mlynarska A, Golba K, Sosnowski M, Ameta D, Goyal M, Kumar D, Chandra S, Sethi R, Puri A, Dwivedi SK, Narain VS, Saran RK, Nekolla S, Rischpler C, Nicolosi S, Langwieser N, Dirschinger R, Laugwitz K, Schwaiger M, Goral JL, Napoli J, Forcada P, Zucchiatti N, Damico A, Damico A, Olivieri D, Lavorato M, Dubesarsky E, Montana O, Salgado C, Jimenez-Heffernan A, Ramos-Font C, Lopez-Martin J, Sanchez De Mora E, Lopez-Aguilar R, Manovel A, Martinez A, Rivera F, Soriano E, Maroz-Vadalazhskaya N, Trisvetova E, Vrublevskaya O, Abazid R, Kattea M, Saqqah H, Sayed S, Smettei O, Winther S, Svensson M, Birn H, Jorgensen H, Botker H, Ivarsen P, Bottcher M, Maaniitty T, Stenstrom I, Saraste A, Pikkarainen E, Uusitalo V, Ukkonen H, Kajander S, Bax J, Knuuti J, Choi T, Park H, Lee C, Lee J, Seo Y, Cho Y, Hwang E, Cho D, Sanchez Enrique C, Ferrera C, Olmos C, Jimenez - Ballve A, Perez - Castejon MJ, Fernandez C, Vivas D, Vilacosta I, Nagamachi S, Onizuka H, Nishii R, Mizutani Y, Kitamura K, Lo Presti M, Polizzi V, Pino P, Luzi G, Bellavia D, Fiorilli R, Madeo A, Malouf J, Buffa V, Musumeci F, Rosales S, Puente A, Zafrir N, Shochat T, Mats A, Solodky A, Kornowski R, Lorber A, Boemio A, Pellegrino T, Paolillo S, Piscopo V, Carotenuto R, Russo B, Pellegrino S, De Matteis G, Perrone-Filardi P, Cuocolo A, Piscopo V, Pellegrino T, Boemio A, Carotenuto R, Russo B, Pellegrino S, De Matteis G, Petretta M, Cuocolo A, Amirov N, Ibatullin M, Sadykov A A, Saifullina G, Ruano R, Diego Dominguez M, Rodriguez Gabella T, Diego Nieto A, Diaz Gonzalez L, Garcia-Talavera J, Sanchez Fernandez P, Leen A, Al Younis I, Zandbergen-Harlaar S, Verberne H, Gimelli A, Veltman C, Wolterbeek R, Bax J, Scholte A, Mooney D, Rosenblatt J, Dunn T, Vasaiwala S, Okuda K, Nakajima K, Nystrom K, Edenbrandt L, Matsuo S, Wakabayashi H, Hashimoto M, Kinuya S, Iric-Cupic V, Milanov S, Davidovic G, Zdravkovic V, Ashikaga K, Yoneyama K, Akashi Y, Shugushev Z, Maximkin D, Chepurnoy A, Volkova O, Baranovich V, Faibushevich A, El Tahlawi M, Elmurr A, Alzubaidi S, Sakrana A, Gouda M, El Tahlawi R, Sellem A, Melki S, Elajmi W, Hammami H, Okano M, Kato T, Kimura M, Funasako M, Nakane E, Miyamoto S, Izumi T, Haruna T, Inoko M, Massardo T, Swett E, Fernandez R, Vera V, Zhindon J, Fernandez R, Swett E, Vera V, Zhindon J, Alay R, Massardo T, Ohshima S, Nishio M, Kojima A, Tamai S, Kobayashi T, Murohara T, Burrell S, Van Rosendael A, Van Den Hoogen I, De Graaf M, Roelofs J, Kroft L, Bax J, Scholte A, Rjabceva I, Krumina G, Kalvelis A, Chanakhchyan F, Vakhromeeva M, Kankiya E, Koppes J, Knol R, Wondergem M, Van Der Ploeg T, Van Der Zant F, Lazarenko SV, Bruin VS, Pan XB, Declerck JM, Van Der Zant FM, Knol RJJ, Juarez-Orozco LE, Alexanderson E, Slart R, Tio R, Dierckx R, Zeebregts C, Boersma H, Hillege H, Martinez-Aguilar M, Jordan-Rios A, Christensen TE, Ahtarovski KA, Bang LE, Holmvang L, Soeholm H, Ghotbi AA, Andersson H, Ihlemann N, Kjaer A, Hasbak P, Gulya M, Lishmanov YB, Zavadovskii K, Lebedev D, Stahle M, Hellberg S, Liljenback H, Virta J, Metsala O, Yla-Herttuala S, Saukko P, Knuuti J, Saraste A, Roivainen A, Thackeray J, Wang Y, Bankstahl J, Wollert K, Bengel F, Saushkina Y, Evtushenko V, Minin S, Efimova I, Evtushenko A, Smishlyaev K, Lishmanov Y, Maslov L, Okuda K, Nakajima K, Kirihara Y, Sugino S, Matsuo S, Taki J, Hashimoto M, Kinuya S, Ahmadian A, Berman J, Govender P, Ruberg F, Miller E, Piriou N, Pallardy A, Valette F, Cahouch Z, Mathieu C, Warin-Fresse K, Gueffet J, Serfaty J, Trochu J, Kraeber-Bodere F, Van Dijk J, Mouden M, Ottervanger J, Van Dalen J, Jager P, Zafrir N, Ofrk H, Vaturi M, Shochat T, Hassid Y, Belzer D, Sagie A, Kornowski R, Kaminek M, Metelkova I, Budikova M, Koranda P, Henzlova L, Sovova E, Kincl V, Drozdova A, Jordan M, Shahid F, Teoh Y, Thamen R, Hara N, Onoguchi M, Hojyo O, Kawaguchi Y, Murai M, Udaka F, Matsuzawa Y, Bulugahapitiya DS, Avison M, Martin J, Liu YH, Wu J, Liu C, Sinusas A, Daou D, Sabbah R, Bouladhour H, Coaguila C, Aguade-Bruix S, Pizzi M, Romero-Farina G, Candell-Riera J, Castell-Conesa J, Patchett N, Sverdlov A, Miller E, Daou D, Sabbah R, Bouladhour H, Coaguila C, Smettei O, Abazid R, Boulaamayl El Fatemi S, Sallam L, Snipelisky D, Park J, Ray J, Shapiro B, Kostkiewicz M, Szot W, Holcman K, Lesniak-Sobelga A, Podolec P, Clerc O, Possner M, Liga R, Vontobel J, Mikulicic F, Graeni C, Benz D, Herzog B, Gaemperli O, Kaufmann P. Poster Session 1: Sunday 3 May 2015, 08:30-18:00 * Room: Poster Area. Eur Heart J Cardiovasc Imaging 2015. [DOI: 10.1093/ehjci/jev051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
Amilorides, well-known inhibitors of Na(+)/H(+) antiporters, were previously shown to inhibit bacterial and mitochondrial NADH-quinone oxidoreductase (complex I) but were markedly less active for complex I. Because membrane subunits ND2, ND4, and ND5 of bovine complex I are homologous to Na(+)/H(+) antiporters, amilorides have been thought to bind to any or all of the antiporter-like subunits; however, there is currently no direct experimental evidence that supports this notion. To identify the binding site of amilorides in bovine complex I, we synthesized two photoreactive amilorides (PRA1 and PRA2), which have a photoreactive azido (-N3) group and terminal alkyne (-C≡CH) group at the opposite ends of the molecules, respectively, and conducted photoaffinity labeling with bovine heart submitochondrial particles. The terminal alkyne group allows various molecular tags to covalently attach to it via Cu(+)-catalyzed click chemistry, thereby allowing purification and/or detection of the labeled peptides. Proteomic analyses revealed that PRA1 and PRA2 label none of the antiporter-like subunits; they specifically label the accessory subunit B14.5a and core subunit 49 kDa (N-terminal region of Thr25-Glu115), respectively. Suppressive effects of ordinary inhibitors (bullatacin, fenpyroximate, and quinazoline), which bind to the putative quinone binding pocket, on labeling were fairly different between the B14.5a and 49 kDa subunits probably because the binding positions of the three inhibitors differ within the pocket. The results of this study clearly demonstrate that amilorides inhibit complex I activity by occupying the quinone binding pocket rather than directly blocking translocation of protons through the antiporter-like subunits (ND2, ND4, and ND5). The accessory subunit B14.5a may be located adjacent to the N-terminal region of the 49 kDa subunits. The structural features of the quinone binding pocket in bovine complex I were discussed on the basis of these results.
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Affiliation(s)
- Masatoshi Murai
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Sonomi Murakami
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Takeshi Ito
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Murai M, Habu S, Murakami S, Ito T, Miyoshi H. Production of new amilorides as potent inhibitors of mitochondrial respiratory complex I. Biosci Biotechnol Biochem 2015; 79:1061-6. [PMID: 25731956 DOI: 10.1080/09168451.2015.1010479] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Amilorides, well-known inhibitors of Na(+)/H(+) antiporters, have also shown to inhibit bacterial and mitochondrial NADH-quinone oxidoreductase (complex I). Since the membrane subunits ND2, ND4, and ND5 of bovine mitochondrial complex I are homologous to Na(+)/H(+) antiporters, amilorides have been thought to bind to any or all of the antiporter-like subunits; however, there is no direct experimental evidence in support of this notion. Photoaffinity labeling is a powerful technique to identify the binding site of amilorides in bovine complex I. Commercially available amilorides such as 5-(N-ethyl-N-isopropyl)amiloride are not suitable as design templates to synthesize photoreactive amilorides because of their low binding affinities to bovine complex I. Thereby, we attempted to modify the structures of commercially available amilorides in order to obtain more potent derivatives. We successfully produced two photoreactive amilorides (PRA1 and PRA2) with a photolabile azido group at opposite ends of the molecule.
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Affiliation(s)
- Masatoshi Murai
- a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kyoto , Japan
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Masuya T, Murai M, Morisaka H, Miyoshi H. Pinpoint Chemical Modification of Asp160 in the 49 kDa Subunit of Bovine Mitochondrial Complex I via a Combination of Ligand-Directed Tosyl Chemistry and Click Chemistry. Biochemistry 2014; 53:7816-23. [DOI: 10.1021/bi501342w] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Takahiro Masuya
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Masatoshi Murai
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hironobu Morisaka
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hideto Miyoshi
- Division of Applied Life
Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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Abstract
We have investigated the antitumor effects of human lymphoblastoid interferon (HLBI) mini-pellets, interleukin-2 (IL-2) entrapped in liposome (IL-2 liposome) and an immune complex of IL-2 and monoclonal antibody against IL-2 (IC-1). The HLBI mini-pellets were administered to nude mice bearing a human renal cancer cell line (KU-2). HLBI levels remained detectable both in the tumor tissue and the serum up to 10 days after peritumor injection. The HLBI mini-pellet significantly suppressed tumor growth by peritumor administration. The antitumor effect of IL-2 liposome on Renca, a murine renal cancer, resulted in the inhibition of tumor growth. An accumulation of Lyt-2(-) and L3T4 lymphocytes was seen in the tumor tissue which was treated with IL-2 liposomes. The IC-1 was prepared by mixing IL-2 and anti-IL-2 monoclonal antibody at a molar ratio of 2: 1. Plasma IL-2 levels were sustained longer in mice given the IC-1 than in mice given IL-2 alone. The IC-1 complex exerted a more significant antitumor effect by local administration in Renca-bearing mice than the administration of IL-2 alone. We speculated that these effects were a result of sustained tumor IL-2 levels due to the increase in molecular weight. The results we obtained indicate that the cytokine drug delivery system has a long-acting cytotoxicity by administration to the tumor sites through efficient stimulation of the local immune response, and thus provides a useful tool for treatment of renal cell carcinoma.
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Affiliation(s)
- K Marumo
- Department of Urology, School of Medicine, Keio University, Tokyo, Japan
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Murai M, Miyoshi H. Chemical modifications of respiratory complex I for structural and functional studies. J Bioenerg Biomembr 2014; 46:313-21. [DOI: 10.1007/s10863-014-9562-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 06/26/2014] [Indexed: 01/07/2023]
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Inagaki N, Watada H, Murai M, Kagimura T, Gong Y, Patel S, Woerle HJ. Linagliptin provides effective, well-tolerated add-on therapy to pre-existing oral antidiabetic therapy over 1 year in Japanese patients with type 2 diabetes. Diabetes Obes Metab 2013; 15:833-43. [PMID: 23565760 DOI: 10.1111/dom.12110] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 02/26/2013] [Accepted: 03/24/2013] [Indexed: 01/26/2023]
Abstract
AIMS To evaluate the long-term safety and efficacy of linagliptin as add-on therapy to one approved oral antidiabetic drug (OAD) in Japanese patients with type 2 diabetes mellitus and insufficient glycaemic control. METHODS This 52-week, multicentre, open-label, parallel-group study evaluated once-daily linagliptin 5 mg as add-on therapy to one OAD [biguanide, glinide, glitazone, sulphonylurea (SU) or α-glucosidase inhibitors (A-GI)] in 618 patients. After a 2-week run-in, patients on SU or A-GI were randomized to either linagliptin (once daily, 5 mg) or metformin (twice or thrice daily, up to 2250 mg/day) as add-on therapy. Patients receiving the other OADs received linagliptin add-on therapy (non-randomized). RESULTS Adverse events were mostly mild or moderate, and rates were similar across all groups. Hypoglycaemic events were rare, except in the SU group. Overall, 26 (5.8%) hypoglycaemic events were reported in patients receiving linagliptin (non-randomized). Hypoglycaemic events were similar for linagliptin and metformin added to A-GI (1/61 vs. 2/61, respectively) or SU (17/124 vs. 10/63, respectively). Significant reductions in glycated haemoglobin (HbA1c) levels (between -0.7 and -0.9%) occurred throughout the study period for the background therapy groups that received linagliptin (baseline HbA1c 7.9-8.1%). The decline in HbA1c levels was indistinguishable between linagliptin and metformin groups when administered as add-on therapy to A-GI or SU. CONCLUSIONS Once-daily linagliptin showed safety and tolerability over 1 year and provided effective add-on therapy leading to significant HbA1c reductions, similar to metformin, over 52 weeks in Japanese patients.
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Affiliation(s)
- N Inagaki
- Department of Diabetes and Clinical Nutrition, Kyoto University Graduate School of Medicine, Kyoto, Japan.
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Oshiro Y, Nakagawa K, Hoshinaga K, Aikawa A, Shishido S, Yoshida K, Asano T, Murai M, Hasegawa A. A Japanese Multicenter Study of High-Dose Mizoribine Combined With Cyclosporine, Basiliximab, and Corticosteroid in Renal Transplantation (The Fourth Report). Transplant Proc 2013; 45:1476-80. [DOI: 10.1016/j.transproceed.2013.03.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 02/16/2013] [Accepted: 03/04/2013] [Indexed: 01/03/2023]
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Shiraishi Y, Murai M, Sakiyama N, Ifuku K, Miyoshi H. Fenpyroximate Binds to the Interface between PSST and 49 kDa Subunits in Mitochondrial NADH-Ubiquinone Oxidoreductase. Biochemistry 2012; 51:1953-63. [DOI: 10.1021/bi300047h] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yusuke Shiraishi
- 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
| | - Naoto Sakiyama
- 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
| | - 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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Kamada H, Matsui Y, Sakurai Y, Tanigawa T, Itoh M, Kawamoto S, Kai K, Sasaki T, Takahashi K, Hayashi M, Takayama Y, Nakamura M, Kadokawa H, Ueda Y, Sutoh M, Murai M. Twelve oxo-eicosatetraenoic acid induces fetal membrane release after delivery in cows. Placenta 2011; 33:106-13. [PMID: 22118869 DOI: 10.1016/j.placenta.2011.11.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 10/29/2011] [Accepted: 11/01/2011] [Indexed: 10/15/2022]
Abstract
Fetal fibroblast cell culture from cotyledons of bovine placenta and animal experiments close to term were used to elucidate afterbirth release and factors missing in the signal transduction mechanism for retained fetal membranes (RFM) after delivery. In cell culture the addition of arachidonic acid (Ara) to the medium caused rapid release to free floating cell in the culture dish, accompanied by matrix metalloproteinase (MMP) activation, being consistent with previous in vivo observations, where a relation between MMP and fetal membrane release had been shown. Ara-induced cell floating was not inhibited by the addition of cyclooxygenase (COX) inhibitor, and not induced by the addition of PGF2α or PGE2 to replace Ara, while 12-lipoxygenase (12-LOX) metabolite of Ara, 12-oxo-eicosatetraenoic acid (12-oxoETE), strongly induced cell floating. In the animal experiments, 12-oxoETE injection to delivery-induced cows (n = 6) using prostaglandin (PG) and dexamethazone resulted in rapid release of fetal membranes. In cows with natural calf delivery, a 12-oxoETE peak (11.7-16.8 ng/ml) was observed in maternal blood plasma prior to release of fetal membranes. This investigation thus gives new indications for that the mediator for fetal membrane release is 12-oxoETE and not PG.
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Affiliation(s)
- H Kamada
- NARO Institute of Livestock and Grassland Science, Ibaraki 305-0901, Japan.
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Hinotsu S, Akaza H, Usami M, Ogawa O, Kitamura T, Suzuki K, Tsukamoto T, Naito S, Namiki M, Hirao Y, Murai M. MP-16.14 Improved Grouping System Combining Gleason Score for Group IV of TNM Prognostic Grouping for Prostate Cancer: Results from J-CAP Database. Urology 2011. [DOI: 10.1016/j.urology.2011.07.382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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