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Chaudhury S, Narasimharao Meka P, Banerjee M, Kent CN, Blagg BSJ. Structure-Based Design, Synthesis, and Biological Evaluation of Hsp90β-Selective Inhibitors. Chemistry 2021; 27:14747-14764. [PMID: 34449940 PMCID: PMC8790780 DOI: 10.1002/chem.202102574] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Indexed: 11/06/2022]
Abstract
The 90 kDa heat shock proteins (Hsp90) are molecular chaperones that are responsible for the folding and/or trafficking of ∼400 client proteins, many of which are directly associated with cancer progression. Consequently, inhibition of Hsp90 can exhibit similar activity as combination therapy as multiple signaling nodes can be targeted simultaneously. In fact, seventeen small-molecule inhibitors that bind the Hsp90 N-terminus entered clinical trials for the treatment of cancer, all of which exhibited pan-inhibitory activity against all four Hsp90 isoforms. Unfortunately, most demonstrated undesired effects alongside induction of the pro-survival heat shock response. As a result, isoform-selective inhibitors have been sought to overcome these detriments. Described herein is a structure-based approach to design Hsp90β-selective inhibitors along with preliminary SAR. In the end, compound 5 was shown to manifest ∼370-fold selectivity for Hsp90β versus Hsp90α, and induced the degradation of select Hsp90β-dependent clients. These data support the development of Hsp90β-selective inhibitors as a new paradigm to overcome the detriments associated with pan-inhibition of Hsp90.
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Affiliation(s)
- Subhabrata Chaudhury
- Department of Chemistry and Biochemistry, Warren Family Research Center for Drug Discovery and Development, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Penchala Narasimharao Meka
- Department of Chemistry and Biochemistry, Warren Family Research Center for Drug Discovery and Development, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Monimoy Banerjee
- Department of Chemistry and Biochemistry, Warren Family Research Center for Drug Discovery and Development, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Caitlin N Kent
- Department of Chemistry and Biochemistry, Warren Family Research Center for Drug Discovery and Development, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Brian S J Blagg
- Department of Chemistry and Biochemistry, Warren Family Research Center for Drug Discovery and Development, University of Notre Dame, Notre Dame, IN, 46556, USA
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Sarewicz M, Pintscher S, Pietras R, Borek A, Bujnowicz Ł, Hanke G, Cramer WA, Finazzi G, Osyczka A. Catalytic Reactions and Energy Conservation in the Cytochrome bc1 and b6f Complexes of Energy-Transducing Membranes. Chem Rev 2021; 121:2020-2108. [PMID: 33464892 PMCID: PMC7908018 DOI: 10.1021/acs.chemrev.0c00712] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Indexed: 12/16/2022]
Abstract
This review focuses on key components of respiratory and photosynthetic energy-transduction systems: the cytochrome bc1 and b6f (Cytbc1/b6f) membranous multisubunit homodimeric complexes. These remarkable molecular machines catalyze electron transfer from membranous quinones to water-soluble electron carriers (such as cytochromes c or plastocyanin), coupling electron flow to proton translocation across the energy-transducing membrane and contributing to the generation of a transmembrane electrochemical potential gradient, which powers cellular metabolism in the majority of living organisms. Cytsbc1/b6f share many similarities but also have significant differences. While decades of research have provided extensive knowledge on these enzymes, several important aspects of their molecular mechanisms remain to be elucidated. We summarize a broad range of structural, mechanistic, and physiological aspects required for function of Cytbc1/b6f, combining textbook fundamentals with new intriguing concepts that have emerged from more recent studies. The discussion covers but is not limited to (i) mechanisms of energy-conserving bifurcation of electron pathway and energy-wasting superoxide generation at the quinol oxidation site, (ii) the mechanism by which semiquinone is stabilized at the quinone reduction site, (iii) interactions with substrates and specific inhibitors, (iv) intermonomer electron transfer and the role of a dimeric complex, and (v) higher levels of organization and regulation that involve Cytsbc1/b6f. In addressing these topics, we point out existing uncertainties and controversies, which, as suggested, will drive further research in this field.
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Affiliation(s)
- Marcin Sarewicz
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Sebastian Pintscher
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Rafał Pietras
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Arkadiusz Borek
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Łukasz Bujnowicz
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
| | - Guy Hanke
- School
of Biological and Chemical Sciences, Queen
Mary University of London, London E1 4NS, U.K.
| | - William A. Cramer
- Department
of Biological Sciences, Purdue University, West Lafayette, Indiana 47907 United States
| | - Giovanni Finazzi
- Laboratoire
de Physiologie Cellulaire et Végétale, Université Grenoble Alpes, Centre National Recherche Scientifique,
Commissariat Energie Atomique et Energies Alternatives, Institut National
Recherche l’agriculture, l’alimentation et l’environnement, 38054 Grenoble Cedex 9, France
| | - Artur Osyczka
- Department
of Molecular Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, 30-387 Kraków, Poland
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Cheng H, Yang L, Liu HF, Zhang R, Chen C, Wu Y, Jiang W. N-(4-(2-chloro-4-(trifluoromethyl)phenoxy)phenyl)picolinamide as a new inhibitor of mitochondrial complex III: Synthesis, biological evaluation and computational simulations. Bioorg Med Chem Lett 2020; 30:127302. [DOI: 10.1016/j.bmcl.2020.127302] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 05/15/2020] [Accepted: 05/31/2020] [Indexed: 01/23/2023]
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4
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Cheng H, Liu HF, Yang L, Zhang R, Chen C, Wu Y, Jiang W. N-(3,5-Dichloro-4-(2,4,6-trichlorophenoxy)phenyl)benzenesulfonamide: A new dual-target inhibitor of mitochondrial complex II and complex III via structural simplification. Bioorg Med Chem 2020; 28:115299. [DOI: 10.1016/j.bmc.2019.115299] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/19/2019] [Accepted: 12/26/2019] [Indexed: 12/22/2022]
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5
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Synthesis, biochemical evaluation and computational simulations of new cytochrome bc1 complex inhibitors based on N-(4-aryloxyphenyl) phthalimides. CHINESE CHEM LETT 2018. [DOI: 10.1016/j.cclet.2018.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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6
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Cheng H, Song W, Nie R, Wang YX, Li HL, Jiang XS, Wu JJ, Chen C, Wu QY. Synthesis of new 4-aryloxy- N -arylanilines and their inhibitory activities against succinate-cytochrome c reductase. Bioorg Med Chem Lett 2018; 28:1330-1335. [DOI: 10.1016/j.bmcl.2018.03.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/23/2018] [Accepted: 03/05/2018] [Indexed: 11/26/2022]
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7
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Young DH, Wang NX, Meyer ST, Avila‐Adame C. Characterization of the mechanism of action of the fungicide fenpicoxamid and its metabolite UK-2A. PEST MANAGEMENT SCIENCE 2018; 74:489-498. [PMID: 28960782 PMCID: PMC5813142 DOI: 10.1002/ps.4743] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 08/31/2017] [Accepted: 09/22/2017] [Indexed: 05/04/2023]
Abstract
BACKGROUND Fenpicoxamid is a new fungicide for control of Zymoseptoria tritici, and is a derivative of the natural product UK-2A. Its mode of action and target site interactions have been investigated. RESULTS UK-2A strongly inhibited cytochrome c reductase, whereas fenpicoxamid was much less active, consistent with UK-2A being the fungicidally active species generated from fenpicoxamid by metabolism. Both compounds caused rapid loss of mitochondrial membrane potential in Z. tritici spores. In Saccharomyces cerevisiae, amino acid substitutions N31K, G37C and L198F at the Qi quinone binding site of cytochrome b reduced sensitivity to fenpicoxamid, UK-2A and antimycin A. Activity of fenpicoxamid was not reduced by the G143A exchange responsible for strobilurin resistance. A docking pose for UK-2A at the Qi site overlaid that of antimycin A. Activity towards Botrytis cinerea was potentiated by salicylhydroxamic acid, showing an ability of alternative respiration to mitigate activity. Fungitoxicity assays against Z. tritici field isolates showed no cross-resistance to strobilurin, azole or benzimidazole fungicides. CONCLUSION Fenpicoxamid is a Qi inhibitor fungicide that provides a new mode of action for Z. tritici control. Mutational and modeling studies suggest that the active species UK-2A binds at the Qi site in a similar, but not identical, fashion to antimycin A. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
| | - Nick X Wang
- Dow AgroSciencesDiscovery ResearchIndianapolisINUSA
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Chen C, Wu QY, Shan LY, Zhang B, Verpoort F, Yang GF. Discovery of cytochrome bc1 complex inhibitors inspired by the natural product karrikinolide. RSC Adv 2016. [DOI: 10.1039/c6ra19424a] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Novel and potent inhibitors targeting the cytochrome bc1 complex were discovered from the natural product karrikinolide for the first time.
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Affiliation(s)
- Cheng Chen
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing
- Wuhan University of Technology
- Wuhan 430070
- P. R. China
| | - Qiong-You Wu
- Key Laboratory of Pesticide & Chemical Biology
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Lian-Ying Shan
- Key Laboratory of Pesticide & Chemical Biology
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Bei Zhang
- Key Laboratory of Pesticide & Chemical Biology
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
| | - Francis Verpoort
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing
- Wuhan University of Technology
- Wuhan 430070
- P. R. China
| | - Guang-Fu Yang
- Key Laboratory of Pesticide & Chemical Biology
- College of Chemistry
- Central China Normal University
- Wuhan 430079
- P. R. China
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9
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Recent advanced in bioactive systems containing pyrazole fused with a five membered heterocycle. Eur J Med Chem 2015; 97:732-46. [DOI: 10.1016/j.ejmech.2014.12.023] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 11/28/2014] [Accepted: 12/13/2014] [Indexed: 12/13/2022]
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10
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Cheng H, Shen YQ, Pan XY, Hou YP, Wu QY, Yang GF. Discovery of 1,2,4-triazole-1,3-disulfonamides as dual inhibitors of mitochondrial complex II and complex III. NEW J CHEM 2015. [DOI: 10.1039/c5nj00215j] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1,2,4-Triazole-1,3-disulfonamide derivatives as dual function inhibitors of mitochondrial complex II (SQR) and complex III (cyt bc1) were discovered.
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Affiliation(s)
- Hua Cheng
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Yan-Qing Shen
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Xia-Yan Pan
- Department of Pesticide Science
- College of Plant Protection
- Nanjing Agricultural University
- Nanjing 210095
- P. R. China
| | - Yi-Ping Hou
- Department of Pesticide Science
- College of Plant Protection
- Nanjing Agricultural University
- Nanjing 210095
- P. R. China
| | - Qiong-You Wu
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
| | - Guang-Fu Yang
- Key Laboratory of Pesticide & Chemical Biology
- Ministry of Education
- College of Chemistry
- Central China Normal University
- Wuhan 430079
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Xiao YM, Esser L, Zhou F, Li C, Zhou YH, Yu CA, Qin ZH, Xia D. Studies on inhibition of respiratory cytochrome bc1 complex by the fungicide pyrimorph suggest a novel inhibitory mechanism. PLoS One 2014; 9:e93765. [PMID: 24699450 PMCID: PMC3974799 DOI: 10.1371/journal.pone.0093765] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 03/05/2014] [Indexed: 11/29/2022] Open
Abstract
The respiratory chain cytochrome bc1 complex (cyt bc1) is a major target of numerous antibiotics and fungicides. All cyt bc1 inhibitors act on either the ubiquinol oxidation (QP) or ubiquinone reduction (QN) site. The primary cause of resistance to bc1 inhibitors is target site mutations, creating a need for novel agents that act on alternative sites within the cyt bc1 to overcome resistance. Pyrimorph, a synthetic fungicide, inhibits the growth of a broad range of plant pathogenic fungi, though little is known concerning its mechanism of action. In this study, using isolated mitochondria from pathogenic fungus Phytophthora capsici, we show that pyrimorph blocks mitochondrial electron transport by affecting the function of cyt bc1. Indeed, pyrimorph inhibits the activities of both purified 11-subunit mitochondrial and 4-subunit bacterial bc1 with IC50 values of 85.0 μM and 69.2 μM, respectively, indicating that it targets the essential subunits of cyt bc1 complexes. Using an array of biochemical and spectral methods, we show that pyrimorph acts on an area near the QP site and falls into the category of a mixed-type, noncompetitive inhibitor with respect to the substrate ubiquinol. In silico molecular docking of pyrimorph to cyt b from mammalian and bacterial sources also suggests that pyrimorph binds in the vicinity of the quinol oxidation site.
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Affiliation(s)
- Yu-Mei Xiao
- Department of Applied Chemistry, China Agricultural University, Beijing, China
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, United States of America
| | - Lothar Esser
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, United States of America
| | - Fei Zhou
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, United States of America
| | - Chang Li
- Department of Applied Chemistry, China Agricultural University, Beijing, China
| | - Yi-Hui Zhou
- Department of Applied Chemistry, China Agricultural University, Beijing, China
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, United States of America
| | - Chang-An Yu
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, Oklahoma, United States of America
| | - Zhao-Hai Qin
- Department of Applied Chemistry, China Agricultural University, Beijing, China
- * E-mail: (ZQ); (DX)
| | - Di Xia
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, United States of America
- * E-mail: (ZQ); (DX)
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12
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Rodrigues T, Ressurreição AS, da Cruz FP, Albuquerque IS, Gut J, Carrasco MP, Gonçalves D, Guedes RC, dos Santos DJVA, Mota MM, Rosenthal PJ, Moreira R, Prudêncio M, Lopes F. Flavones as isosteres of 4(1H)-quinolones: discovery of ligand efficient and dual stage antimalarial lead compounds. Eur J Med Chem 2013; 69:872-80. [PMID: 24125849 DOI: 10.1016/j.ejmech.2013.09.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Revised: 09/01/2013] [Accepted: 09/03/2013] [Indexed: 11/20/2022]
Abstract
Malaria is responsible for nearly one million deaths annually, and the increasing prevalence of multi-resistant strains of Plasmodium falciparum poses a great challenge to controlling the disease. A diverse set of flavones, isosteric to 4(1H)-quinolones, were prepared and profiled for their antiplasmodial activity against the blood stage of P. falciparum W2 strain, and the liver stage of the rodent parasite Plasmodium berghei. Ligand efficient leads were identified as dual stage antimalarials, suggesting that scaffold optimization may afford potent antiplasmodial compounds.
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Affiliation(s)
- Tiago Rodrigues
- Research Institute for Medicines and Pharmaceutical Sciences (iMed.UL), Faculty of Pharmacy, University of Lisbon, Av. Prof. Gama Pinto, 1649-019 Lisbon, Portugal.
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13
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Yang WC, Li H, Wang F, Zhu XL, Yang GF. Rieske Iron-Sulfur Protein of the Cytochrome bc1 Complex: A Potential Target for Fungicide Discovery. Chembiochem 2012; 13:1542-51. [DOI: 10.1002/cbic.201200295] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Indexed: 01/17/2023]
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14
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Cankařová N, Hlaváč J, Krchňák V. Recent Synthetic Approaches to 1H- and 2H-Indazoles. A Review. ORG PREP PROCED INT 2010. [DOI: 10.1080/00304948.2010.513898] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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15
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Zhao PL, Wang L, Zhu XL, Huang X, Zhan CG, Wu JW, Yang GF. Subnanomolar inhibitor of cytochrome bc1 complex designed by optimizing interaction with conformationally flexible residues. J Am Chem Soc 2010; 132:185-94. [PMID: 19928849 DOI: 10.1021/ja905756c] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cytochrome bc(1) complex (EC 1.10.2.2, bc(1)), an essential component of the cellular respiratory chain and the photosynthetic apparatus in photosynthetic bacteria, has been identified as a promising target for new drugs and agricultural fungicides. X-ray diffraction structures of the free bc(1) complex and its complexes with various inhibitors revealed that the phenyl group of Phe274 in the binding pocket exhibited significant conformational flexibility upon different inhibitors binding to optimize respective pi-pi interactions, whereas the side chains of other hydrophobic residues showed conformational stability. Therefore, in the present study, a strategy of optimizing the pi-pi interaction with conformationally flexible residues was proposed to design and discover new bc(1) inhibitors with a higher potency. Eight new compounds were designed and synthesized, among which compound 5c, with a K(i) value of 570 pM, was identified as the most promising drug or fungicide candidate, significantly more potent than the commercially available bc(1) inhibitors, including azoxystrobin (AZ), kresoxim-methyl (KM), and pyraclostrobin (PY). To our knowledge, this is the first bc(1) inhibitor discovered from structure-based design with a potency of subnanomolar K(i) value. For all of the compounds synthesized and assayed, the calculated binding free energies correlated reasonably well with the binding free energies derived from the experimental K(i) values, with a correlation coefficient of r(2) = 0.89. The further inhibitory kinetics studies revealed that 5c is a noncompetitive inhibitor with respect to substrate cytochrome c, but it is a competitive inhibitor with respect to substrate ubiquinol. Due to its subnanomolar K(i) potency and slow dissociation rate constant (k(-0) = 0.00358 s(-1)), 5c could be used as a specific probe for further elucidation of the mechanism of bc(1) function and as a new lead compound for future drug discovery.
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Affiliation(s)
- Pei-Liang Zhao
- Key Laboratory of Pesticide & Chemical Biology, College of Chemistry, Ministry of Education, Central China Normal University, Wuhan 430079, PR China
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Zmijewski JW, Lorne E, Banerjee S, Abraham E. Participation of mitochondrial respiratory complex III in neutrophil activation and lung injury. Am J Physiol Lung Cell Mol Physiol 2009; 296:L624-34. [PMID: 19168575 DOI: 10.1152/ajplung.90522.2008] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Reactive oxygen species (ROS) produced during mitochondrial activity participate in the regulation of intracellular signaling pathways. However, there is only limited information concerning the role that ROS derived from the mitochondrial respiratory chain play in modulating neutrophil activity and participation in acute inflammatory processes. Because mitochondrial complex III is a major site of ROS formation, we examined whether selective complex III inhibition, through exposure of neutrophils to myxothiazol or antimycin A, would affect LPS-induced activation. Culture of neutrophils with antimycin A or myxothiazol resulted in increased intracellular levels of ROS, including superoxide and hydrogen peroxide (H(2)O(2)). Inhibition of complex III activity reduced LPS-induced degradation of IkappaB-alpha, nuclear accumulation of NF-kappaB, and proinflammatory cytokine production. The effects of antimycin A or myxothiazol appeared to be dependent on generation of H(2)O(2) since addition of pegylated catalase to neutrophils restored LPS-mediated IkappaB-alpha degradation and production of proinflammatory cytokines. Administration of myxothiazol to mice resulted in diminished mitochondrial complex III activity in the lungs and decreased severity of LPS-induced lung injury. These results indicate that inhibition of mitochondrial complex III diminishes Toll-like receptor 4-induced neutrophil activation through a mechanism dependent on H(2)O(2) generation and also reduces the severity of lung injury due to LPS exposure, a pathophysiologic process in which neutrophils play a major role.
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Affiliation(s)
- Jaroslaw W Zmijewski
- Department of Medicine, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294-0012, USA
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17
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Affiliation(s)
- Andreas Schmidt
- Clausthal University of Technology, Institute of Organic Chemistry, Leibnizstrasse 6, 38678 Clausthal‐Zellerfeld, Germany, Fax: +49‐5323‐722858
| | - Ariane Beutler
- Clausthal University of Technology, Institute of Organic Chemistry, Leibnizstrasse 6, 38678 Clausthal‐Zellerfeld, Germany, Fax: +49‐5323‐722858
| | - Bohdan Snovydovych
- Clausthal University of Technology, Institute of Organic Chemistry, Leibnizstrasse 6, 38678 Clausthal‐Zellerfeld, Germany, Fax: +49‐5323‐722858
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Abstract
Rapid progress in the synthetic application of benzotriazole derivatives in the last 20 years has resulted in over 1000 scientific papers on the subject. This fact is reflected in Section 5.01.7, which involves almost a half of the volume of this chapter. The section is arranged according to hybridization of the C-α atom and atomic numbers of the atoms in positions β and γ to allow an easy access to the material of interest. Recent discovery of copper catalysis in [3+2] cycloadditions of azides to acetylenes, the so-called ‘click chemistry’, which boosted application of the 1,2,3-triazole derivatives, especially in medicinal chemistry, is presented in Section 5.01.9. From the point of view of practical applications, Section 5.01.11 is organized according to the number, position, and combination of the substituents at the aromatic rings. Another novel feature that has no precedence in the previous editions of Comprehensive Heterocyclic Chemistry is an addition of triazole and benzotriazole complexes with various transitions metals to Section 5.01.4.
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