1
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Collins J, Oviatt AA, Chan PF, Osheroff N. Target-Mediated Fluoroquinolone Resistance in Neisseria gonorrhoeae: Actions of Ciprofloxacin against Gyrase and Topoisomerase IV. ACS Infect Dis 2024; 10:1351-1360. [PMID: 38606464 PMCID: PMC11015056 DOI: 10.1021/acsinfecdis.4c00041] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/08/2024] [Accepted: 02/13/2024] [Indexed: 04/13/2024]
Abstract
Fluoroquinolones make up a critically important class of antibacterials administered worldwide to treat human infections. However, their clinical utility has been curtailed by target-mediated resistance, which is caused by mutations in the fluoroquinolone targets, gyrase and topoisomerase IV. An important pathogen that has been affected by this resistance is Neisseria gonorrhoeae, the causative agent of gonorrhea. Over 82 million new cases of this sexually transmitted infection were reported globally in 2020. Despite the impact of fluoroquinolone resistance on gonorrhea treatment, little is known about the interactions of this drug class with its targets in this bacterium. Therefore, we investigated the effects of the fluoroquinolone ciprofloxacin on the catalytic and DNA cleavage activities of wild-type gyrase and topoisomerase IV and the corresponding enzymes that harbor mutations associated with cellular and clinical resistance to fluoroquinolones. Results indicate that ciprofloxacin interacts with both gyrase (its primary target) and topoisomerase IV (its secondary target) through a water-metal ion bridge that has been described in other species. Moreover, mutations in amino acid residues that anchor this bridge diminish the susceptibility of the enzymes for the drug, leading to fluoroquinolone resistance. Results further suggest that ciprofloxacin primarily induces its cytotoxic effects by enhancing gyrase-mediated DNA cleavage as opposed to inhibiting the DNA supercoiling activity of the enzyme. In conclusion, this work links the effects of ciprofloxacin on wild-type and resistant gyrase to results reported for cellular and clinical studies and provides a mechanistic explanation for the targeting and resistance of fluoroquinolones in N. gonorrhoeae.
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Affiliation(s)
- Jessica
A. Collins
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
| | - Alexandria A. Oviatt
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
| | - Pan F. Chan
- Infectious
Diseases Research Unit, GlaxoSmithKline, Collegeville, Pennsylvania 19426, United States
| | - Neil Osheroff
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
- Department
of Medicine (Hematology/Oncology), Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
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2
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Discovery of Quinazoline-2,4(1 H,3 H)-Dione Derivatives as Potential Antibacterial Agent: Design, Synthesis, and Their Antibacterial Activity. Molecules 2022; 27:molecules27123853. [PMID: 35744976 PMCID: PMC9228007 DOI: 10.3390/molecules27123853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 06/06/2022] [Accepted: 06/11/2022] [Indexed: 12/31/2022] Open
Abstract
In this paper, we report on the design and synthesis of a novel series of quinazoline-2,4(1H,3H)-dione derivatives as fluoroquinolone-like inhibitors of bacterial gyrase and DNA topoisomerase IV to identify and develop antimicrobial agents to prevent bacterial resistance problems. Their structures were confirmed using spectroscopic analyses (IR, NMR, and EI-MS). The novel quinazoline-2,4(1H,3H)-dione derivatives were evaluated for their antimicrobial activities against Gram-positive and Gram-negative bacterial strains using the Agar well diffusion method to study the antimicrobial activities and compared them with the standard drugs. Most compounds displayed moderate activity. Among the tested compounds, the most promising compounds 13 and 15 provided broad bioactive spectrum against Gram-positive and Gram-negative strains compared to the standard drugs.
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3
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Alla K, Vijayakumar V, Sarveswari S. Synthesis and In Vitro Antimicrobial Evaluation of New Quinolone Based 2-Arylamino Pyrimidines. Polycycl Aromat Compd 2022. [DOI: 10.1080/10406638.2022.2056209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | | | - S. Sarveswari
- Department of Chemistry, VIT, Vellore, Tamilnadu, India
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4
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Long S, Resende DISP, Palmeira A, Kijjoa A, Silva AMS, Tiritan ME, Pereira-Terra P, Freitas-Silva J, Barreiro S, Silva R, Remião F, Pinto E, Martins da Costa P, Sousa E, Pinto MMM. New marine-derived indolymethyl pyrazinoquinazoline alkaloids with promising antimicrobial profiles. RSC Adv 2020; 10:31187-31204. [PMID: 35520644 PMCID: PMC9056383 DOI: 10.1039/d0ra05319h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/11/2020] [Indexed: 01/03/2023] Open
Abstract
Due to the emergence of multidrug-resistant pathogenic microorganisms, the search for novel antimicrobials is urgent. Inspired by marine alkaloids, a series of indolomethyl pyrazino [1,2-b]quinazoline-3,6-diones was prepared using a one-pot microwave-assisted multicomponent polycondensation of amino acids. The compounds were evaluated for their antimicrobial activity against a panel of nine bacterial strains and five fungal strains. Compounds 26 and 27 were the most effective against Staphylococcus aureus ATCC 29213 reference strain with MIC values of 4 μg mL−1, and a methicillin-resistant Staphylococcus aureus (MRSA) isolate with MIC values of 8 μg mL−1. It was possible to infer that enantiomer (−)-26 was responsible for the antibacterial activity (MIC 4 μg mL−1) while (+)-26 had no activity. Furthermore, compound (−)-26 was able to impair S. aureus biofilm production and no significant cytotoxicity towards differentiated and non-differentiated SH-SY5Y cells was observed. Compounds 26, 28, and 29 showed a weak antifungal activity against Trichophyton rubrum clinical isolate with MIC 128 μg mL−1 and presented a synergistic effect with fluconazole. Indolomethyl pyrazino [1,2-b]quinazoline-3,6-diones were prepared using a one-pot multicomponent polycondensation of amino acids and were evaluated for their antimicrobial activity against a panel of nine bacterial strains and five fungal strains.![]()
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Affiliation(s)
- Solida Long
- LQOF - Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Diana I S P Resende
- LQOF - Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal .,CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal
| | - Andreia Palmeira
- LQOF - Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal .,CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal
| | - Anake Kijjoa
- CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal.,ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Artur M S Silva
- QOPNA - Química Orgânica, Produtos Naturais e Agroalimentares, Departamento de Química, Universidade de Aveiro 3810-193 Aveiro Portugal
| | - Maria Elizabeth Tiritan
- LQOF - Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal .,CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal.,CESPU, Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde (IINFACTS) Rua Central de Gandra, 1317 4585-116 Gandra PRD Portugal
| | - Patrícia Pereira-Terra
- CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal.,ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Joana Freitas-Silva
- CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal.,ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Sandra Barreiro
- UCIBIO-REQUIMTE, Laboratório de Toxicologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Renata Silva
- UCIBIO-REQUIMTE, Laboratório de Toxicologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Fernando Remião
- UCIBIO-REQUIMTE, Laboratório de Toxicologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Eugénia Pinto
- CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal.,Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Paulo Martins da Costa
- CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal.,ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal
| | - Emília Sousa
- LQOF - Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal .,CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal
| | - Madalena M M Pinto
- LQOF - Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto Rua de Jorge Viterbo Ferreira, 228 4050-313 Porto Portugal .,CIIMAR - Centro Interdisciplinar de Investigação Marinha e Ambiental, Terminal de Cruzeiros do Porto de Leixões Av. General Norton de Matos S/N 4450-208 Matosinhos Portugal
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5
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Pham TDM, Ziora ZM, Blaskovich MAT. Quinolone antibiotics. MEDCHEMCOMM 2019; 10:1719-1739. [PMID: 31803393 PMCID: PMC6836748 DOI: 10.1039/c9md00120d] [Citation(s) in RCA: 304] [Impact Index Per Article: 60.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/09/2019] [Indexed: 12/12/2022]
Abstract
The quinolone antibiotics arose in the early 1960s, with the first examples possessing a narrow-spectrum of activity with unfavorable pharmacokinetic properties. Over time, the development of new quinolone antibiotics has led to improved analogues with an expanded spectrum and high efficacy. Nowadays, quinolones are widely used for treating a variety of infections. Quinolones are broad-spectrum antibiotics that are active against both Gram-positive and Gram-negative bacteria, including mycobacteria, and anaerobes. They exert their actions by inhibiting bacterial nucleic acid synthesis through disrupting the enzymes topoisomerase IV and DNA gyrase, and by causing breakage of bacterial chromosomes. However, bacteria have acquired resistance to quinolones, similar to other antibacterial agents, due to the overuse of these drugs. Mechanisms contributing to quinolone resistance are mediated by chromosomal mutations and/or plasmid gene uptake that alter the topoisomerase targets, modify the quinolone, and/or reduce drug accumulation by either decreased uptake or increased efflux. This review discusses the development of this class of antibiotics in terms of potency, pharmacokinetics and toxicity, along with the resistance mechanisms which reduce the quinolones' activity against pathogens. Potential strategies for future generations of quinolone antibiotics with enhanced activity against resistant strains are suggested.
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Affiliation(s)
- Thu D M Pham
- School of Chemistry & Molecular Biosciences , The University of Queensland , Brisbane , QLD 4072 , Australia
| | - Zyta M Ziora
- Institute for Molecular Bioscience , The University of Queensland , Brisbane , QLD 4072 , Australia .
| | - Mark A T Blaskovich
- Institute for Molecular Bioscience , The University of Queensland , Brisbane , QLD 4072 , Australia .
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6
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The C7-aminomethylpyrrolidine group rescues the activity of a thio-fluoroquinolone. Biochimie 2019; 160:24-27. [PMID: 30763638 DOI: 10.1016/j.biochi.2019.02.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 02/05/2019] [Indexed: 01/03/2023]
Abstract
A Mg2+-water bridge between the C-3, C-4 diketo moiety of fluoroquinolones and the conserved amino acid residues in the GyrA/ParC subunit is critical for the binding of a fluoroquinolone to a topoisomerase-DNA covalent complex. The fluoroquinolone UING-5-249 (249) can bind to the GyrB subunit through its C7-aminomethylpyrrolidine group. This interaction is responsible for enhanced activities of 249 against the wild type and quinolone-resistant mutant topoisomerases. To further evaluate the effects of the 249-GyrB interaction on fluoroquinolone activity, we examined the activities of decarboxy- and thio-249 against DNA gyrase and conducted docking studies using the structure of a gyrase-ciprofloxacin-DNA ternary complex. We found that the 249-GyrB interaction rescued the activity of thio-249 but not that of decarboxy-249. A C7-group that binds more strongly to the GyrB subunit may allow for modifications at the C-4 position, leading to a novel compound that is active against the wild type and quinolone-resistant pathogens.
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7
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Oppegard LM, Delgado JL, Kulkarni CA, Towle TR, Hart DE, Williams BP, Lentz SRC, Norris BJ, Flory CM, Schumacher RJ, Murry DJ, Kerns RJ, Hiasa H. Novel N-1 substituted fluoroquinolones inhibit human topoisomerase I activity and exhibit anti-proliferative activity. Invest New Drugs 2018; 37:378-383. [PMID: 30198058 DOI: 10.1007/s10637-018-0666-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 09/04/2018] [Indexed: 11/29/2022]
Abstract
Fluoroquinolone-class agents selectively target the bacterial type IIA topoisomerases DNA gyrase and topoisomerase IV, with a few exceptions that target eukaryotic type IIA topoisomerases. Fluoroquinolones bind and stabilize type IIA topoisomerase-DNA covalent complexes that contain a double-strand break. This unique mode of action is referred to as 'topoisomerase poisoning'. We discovered that two novel fluoroquinolones having aryl functionality at the N-1 position, UITT-3-217 (217) and UITT-3-227 (227), could inhibit the catalytic activity of human topoisomerase II without stabilizing topoisomerase-DNA complexes, i.e., without poisoning it. Surprisingly, these compounds are more effective in inhibiting the catalytic activities of human and bacterial topoisomerase I. The National Cancer Institute's 60 human tumor cell lines screen revealed significant anti-proliferative activities with 217 and 227 against the majority of 60 cancer cell lines. A proof of concept in vivo efficacy study using an HT-29 xenograft model of human colorectal cancer showed that 217 could inhibit the proliferation of human colorectal cancer cells to a degree comparable to fluorouracil in mice. Although 227 also exhibited anti-proliferative activity, it was not as effective as 217 in this xenograft model. These novel fluoroquinolones may serve as promising lead compounds for the development of new anticancer drugs.
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Affiliation(s)
- Lisa M Oppegard
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA.,College of Undergraduate Health Sciences, Northwestern Health Sciences University, Bloomington, MN, 55431, USA
| | - Justine L Delgado
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA, 52242, USA
| | - Chaitanya A Kulkarni
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA, 52242, USA
| | - Tyrell R Towle
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA, 52242, USA.,MedPharm Holdings, Denver, CO, 80239, USA
| | - Delaney E Hart
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Bridget P Williams
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Sarah R C Lentz
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA
| | - Beverly J Norris
- Center for Translational Medicine, University of Minnesota Academic Health Center, 515 Delaware Street SE, Room 2-191, Minneapolis, MN, 55455, USA
| | - Craig M Flory
- Center for Translational Medicine, University of Minnesota Academic Health Center, 515 Delaware Street SE, Room 2-191, Minneapolis, MN, 55455, USA
| | - Robert J Schumacher
- Center for Translational Medicine, University of Minnesota Academic Health Center, 515 Delaware Street SE, Room 2-191, Minneapolis, MN, 55455, USA
| | - Daryl J Murry
- The Division of Pharmaceutics and Translational Therapeutics, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA, 52242, USA.,Department of Pharmacy Practice, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Robert J Kerns
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA, 52242, USA
| | - Hiroshi Hiasa
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN, 55455, USA.
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8
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Germe T, Vörös J, Jeannot F, Taillier T, Stavenger RA, Bacqué E, Maxwell A, Bax BD. A new class of antibacterials, the imidazopyrazinones, reveal structural transitions involved in DNA gyrase poisoning and mechanisms of resistance. Nucleic Acids Res 2018; 46:4114-4128. [PMID: 29538767 PMCID: PMC5934680 DOI: 10.1093/nar/gky181] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 02/16/2018] [Accepted: 03/02/2018] [Indexed: 12/24/2022] Open
Abstract
Imidazopyrazinones (IPYs) are a new class of compounds that target bacterial topoisomerases as a basis for their antibacterial activity. We have characterized the mechanism of these compounds through structural/mechanistic studies showing they bind and stabilize a cleavage complex between DNA gyrase and DNA ('poisoning') in an analogous fashion to fluoroquinolones, but without the requirement for the water-metal-ion bridge. Biochemical experiments and structural studies of cleavage complexes of IPYs compared with an uncleaved gyrase-DNA complex, reveal conformational transitions coupled to DNA cleavage at the DNA gate. These involve movement at the GyrA interface and tilting of the TOPRIM domains toward the scissile phosphate coupled to capture of the catalytic metal ion. Our experiments show that these structural transitions are involved generally in poisoning of gyrase by therapeutic compounds and resemble those undergone by the enzyme during its adenosine triphosphate-coupled strand-passage cycle. In addition to resistance mutations affecting residues that directly interact with the compounds, we characterized a mutant (D82N) that inhibits formation of the cleavage complex by the unpoisoned enzyme. The D82N mutant appears to act by stabilizing the binary conformation of DNA gyrase with uncleaved DNA without direct interaction with the compounds. This provides general insight into the resistance mechanisms to antibiotics targeting bacterial type II topoisomerases.
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Affiliation(s)
- Thomas Germe
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Judit Vörös
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Frederic Jeannot
- Sanofi R&D, TSU Infectious Diseases, 1541 Avenue Marcel Mérieux, 69280 Marcy L’Etoile, France
| | - Thomas Taillier
- Sanofi R&D, TSU Infectious Diseases, 1541 Avenue Marcel Mérieux, 69280 Marcy L’Etoile, France
| | - Robert A Stavenger
- Antibacterial Discovery Performance Unit, Infectious Diseases Therapy Area Unit, GlaxoSmithKline, 1250 Collegeville Road, Collegeville, PA 19426, USA
| | - Eric Bacqué
- Sanofi R&D, TSU Infectious Diseases, 1541 Avenue Marcel Mérieux, 69280 Marcy L’Etoile, France
| | - Anthony Maxwell
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Benjamin D Bax
- Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
- Platform Technology and Science, GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2NY, UK
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9
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Abstract
DNA topoisomerases are proven therapeutic targets of antibacterial agents. Quinolones, especially fluoroquinolones, are the most successful topoisomerase-targeting antibacterial drugs. These drugs target type IIA topoisomerases in bacteria. Recent structural and biochemical studies on fluoroquinolones have provided the molecular basis for both their mechanism of action, as well as the molecular basis of bacterial resistance. Due to the development of drug resistance, including fluoroquinolone resistance, among bacterial pathogens, there is an urgent need to discover novel antibacterial agents. Recent advances in topoisomerase inhibitors may lead to the development of novel antibacterial drugs that are effective against fluoroquinolone-resistant pathogens. They include type IIA topoisomerase inhibitors that either interact with the GyrB/ParE subunit or form nick-containing ternary complexes. In addition, several topoisomerase I inhibitors have recently been identified. Thus, DNA topoisomerases remain important targets of antibacterial agents.
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10
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Malik M, Mustaev A, Schwanz HA, Luan G, Shah N, Oppegard LM, de Souza EC, Hiasa H, Zhao X, Kerns RJ, Drlica K. Suppression of gyrase-mediated resistance by C7 aryl fluoroquinolones. Nucleic Acids Res 2016; 44:3304-16. [PMID: 26984528 PMCID: PMC4838383 DOI: 10.1093/nar/gkw161] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 03/02/2016] [Indexed: 11/16/2022] Open
Abstract
Fluoroquinolones form drug-topoisomerase-DNA complexes that rapidly block transcription and replication. Crystallographic and biochemical studies show that quinolone binding involves a water/metal-ion bridge between the quinolone C3-C4 keto-acid and amino acids in helix-4 of the target proteins, GyrA (gyrase) and ParC (topoisomerase IV). A recent cross-linking study revealed a second drug-binding mode in which the other end of the quinolone, the C7 ring system, interacts with GyrA. We report that addition of a dinitrophenyl (DNP) moiety to the C7 end of ciprofloxacin (Cip-DNP) reduced protection due to resistance substitutions in Escherichia coli GyrA helix-4, consistent with the existence of a second drug-binding mode not evident in X-ray structures of drug-topoisomerase-DNA complexes. Several other C7 aryl fluoroquinolones behaved in a similar manner with particular GyrA mutants. Treatment of E. coli cultures with Cip-DNP selectively enriched an uncommon variant, GyrA-A119E, a change that may impede binding of the dinitrophenyl group at or near the GyrA-GyrA interface. Collectively the data support the existence of a secondary quinolone-binding mode in which the quinolone C7 ring system interacts with GyrA; the data also identify C7 aryl derivatives as a new way to obtain fluoroquinolones that overcome existing GyrA-mediated quinolone resistance.
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Affiliation(s)
- Muhammad Malik
- Public Heath Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA
| | - Arkady Mustaev
- Public Heath Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA
| | - Heidi A Schwanz
- University of Iowa, Division of Medicinal & Natural Products Chemistry, College of Pharmacy, Iowa City, IA 52246, USA
| | - Gan Luan
- Public Heath Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA
| | - Nirali Shah
- Public Heath Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA
| | - Lisa M Oppegard
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Ernane C de Souza
- University of Iowa, Division of Medicinal & Natural Products Chemistry, College of Pharmacy, Iowa City, IA 52246, USA
| | - Hiroshi Hiasa
- Department of Pharmacology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Xilin Zhao
- Public Heath Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA Department of Microbiology, Biochemistry & Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, South Xiang-An Road, Xiang-An District, Xiamen, Fujian Province 361102, China
| | - Robert J Kerns
- University of Iowa, Division of Medicinal & Natural Products Chemistry, College of Pharmacy, Iowa City, IA 52246, USA
| | - Karl Drlica
- Public Heath Research Institute, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA Department of Microbiology, Biochemistry & Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Science, 225 Warren Street, Newark, NJ 07103, USA
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11
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Crystal structure and stability of gyrase-fluoroquinolone cleaved complexes from Mycobacterium tuberculosis. Proc Natl Acad Sci U S A 2016; 113:1706-13. [PMID: 26792525 DOI: 10.1073/pnas.1525047113] [Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) infects one-third of the world's population and in 2013 accounted for 1.5 million deaths. Fluoroquinolone antibacterials, which target DNA gyrase, are critical agents used to halt the progression from multidrug-resistant tuberculosis to extensively resistant disease; however, fluoroquinolone resistance is emerging and new ways to bypass resistance are required. To better explain known differences in fluoroquinolone action, the crystal structures of the WT Mtb DNA gyrase cleavage core and a fluoroquinolone-sensitized mutant were determined in complex with DNA and five fluoroquinolones. The structures, ranging from 2.4- to 2.6-Å resolution, show that the intrinsically low susceptibility of Mtb to fluoroquinolones correlates with a reduction in contacts to the water shell of an associated magnesium ion, which bridges fluoroquinolone-gyrase interactions. Surprisingly, the structural data revealed few differences in fluoroquinolone-enzyme contacts from drugs that have very different activities against Mtb. By contrast, a stability assay using purified components showed a clear relationship between ternary complex reversibility and inhibitory activities reported with cultured cells. Collectively, our data indicate that the stability of fluoroquinolone/DNA interactions is a major determinant of fluoroquinolone activity and that moieties that have been appended to the C7 position of different quinolone scaffolds do not take advantage of specific contacts that might be made with the enzyme. These concepts point to new approaches for developing quinolone-class compounds that have increased potency against Mtb and the ability to overcome resistance.
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Fluoroquinolone interactions with Mycobacterium tuberculosis gyrase: Enhancing drug activity against wild-type and resistant gyrase. Proc Natl Acad Sci U S A 2016; 113:E839-46. [PMID: 26792518 DOI: 10.1073/pnas.1525055113] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mycobacterium tuberculosis is a significant source of global morbidity and mortality. Moxifloxacin and other fluoroquinolones are important therapeutic agents for the treatment of tuberculosis, particularly multidrug-resistant infections. To guide the development of new quinolone-based agents, it is critical to understand the basis of drug action against M. tuberculosis gyrase and how mutations in the enzyme cause resistance. Therefore, we characterized interactions of fluoroquinolones and related drugs with WT gyrase and enzymes carrying mutations at GyrA(A90) and GyrA(D94). M. tuberculosis gyrase lacks a conserved serine that anchors a water-metal ion bridge that is critical for quinolone interactions with other bacterial type II topoisomerases. Despite the fact that the serine is replaced by an alanine (i.e., GyrA(A90)) in M. tuberculosis gyrase, the bridge still forms and plays a functional role in mediating quinolone-gyrase interactions. Clinically relevant mutations at GyrA(A90) and GyrA(D94) cause quinolone resistance by disrupting the bridge-enzyme interaction, thereby decreasing drug affinity. Fluoroquinolone activity against WT and resistant enzymes is enhanced by the introduction of specific groups at the C7 and C8 positions. By dissecting fluoroquinolone-enzyme interactions, we determined that an 8-methyl-moxifloxacin derivative induces high levels of stable cleavage complexes with WT gyrase and two common resistant enzymes, GyrA(A90V) and GyrA(D94G). 8-Methyl-moxifloxacin was more potent than moxifloxacin against WT M. tuberculosis gyrase and displayed higher activity against the mutant enzymes than moxifloxacin did against WT gyrase. This chemical biology approach to defining drug-enzyme interactions has the potential to identify novel drugs with improved activity against tuberculosis.
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Oppegard LM, Schwanz HA, Towle TR, Kerns RJ, Hiasa H. Fluoroquinolones stimulate the DNA cleavage activity of topoisomerase IV by promoting the binding of Mg(2+) to the second metal binding site. Biochim Biophys Acta Gen Subj 2015; 1860:569-75. [PMID: 26723176 DOI: 10.1016/j.bbagen.2015.12.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 12/14/2015] [Accepted: 12/22/2015] [Indexed: 01/03/2023]
Abstract
BACKGROUND Fluoroquinolones target bacterial type IIA topoisomerases, DNA gyrase and topoisomerase IV (Topo IV). Fluoroquinolones trap a topoisomerase-DNA covalent complex as a topoisomerase-fluoroquinolone-DNA ternary complex and ternary complex formation is critical for their cytotoxicity. A divalent metal ion is required for type IIA topoisomerase-catalyzed strand breakage and religation reactions. Recent studies have suggested that type IIA topoisomerases use two metal ions, one structural and one catalytic, to carry out the strand breakage reaction. METHODS We conducted a series of DNA cleavage assays to examine the effects of fluoroquinolones and quinazolinediones on Mg(2+)-, Mn(2+)-, or Ca(2+)-supported DNA cleavage activity of Escherichia coli Topo IV. RESULTS In the absence of any drug, 20-30 mM Mg(2+) was required for the maximum levels of the DNA cleavage activity of Topo IV, whereas approximately 1mM of either Mn(2+) or Ca(2+) was sufficient to support the maximum levels of the DNA cleavage activity of Topo IV. Fluoroquinolones promoted the Topo IV-catalyzed strand breakage reaction at low Mg(2+) concentrations where Topo IV alone could not efficiently cleave DNA. CONCLUSIONS AND GENERAL SIGNIFICANCE At low Mg(2+) concentrations, fluoroquinolones may stimulate the Topo IV-catalyzed strand breakage reaction by promoting Mg(2+) binding to metal binding site B through the structural distortion in DNA. As Mg(2+) concentration increases, fluoroquinolones may inhibit the religation reaction by either stabilizing Mg(2+) at site B or inhibition the binding of Mg(2+) to site A. This study provides a molecular basis of how fluoroquinolones stimulate the Topo IV-catalyzed strand breakage reaction by modulating Mg(2+) binding.
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Affiliation(s)
- Lisa M Oppegard
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, USA.
| | - Heidi A Schwanz
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA 52242, USA.
| | - Tyrell R Towle
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA 52242, USA.
| | - Robert J Kerns
- Division of Medicinal and Natural Products Chemistry, Department of Pharmaceutical Sciences and Experimental Therapeutics, University of Iowa, 115 S Grand Ave., S321 Pharmacy Building, Iowa City, IA 52242, USA.
| | - Hiroshi Hiasa
- Department of Pharmacology, University of Minnesota Medical School, 6-120 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, USA.
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Aldred KJ, Schwanz HA, Li G, Williamson BH, McPherson SA, Turnbough CL, Kerns RJ, Osheroff N. Activity of quinolone CP-115,955 against bacterial and human type II topoisomerases is mediated by different interactions. Biochemistry 2015; 54:1278-86. [PMID: 25586498 DOI: 10.1021/bi501073v] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
CP-115,955 is a quinolone with a 4-hydroxyphenyl at C7 that displays high activity against both bacterial and human type II topoisomerases. To determine the basis for quinolone cross-reactivity between bacterial and human enzymes, the activity of CP-115,955 and a series of related quinolones and quinazolinediones against Bacillus anthracis topoisomerase IV and human topoisomerase IIα was analyzed. Results indicate that the activity of CP-115,955 against the bacterial and human enzymes is mediated by different interactions. On the basis of the decreased activity of quinazolinediones against wild-type and resistant mutant topoisomerase IV and the low activity of quinolones against resistant mutant enzymes, it appears that the primary interaction of CP-115,955 with the bacterial system is mediated through the C3/C4 keto acid and the water-metal ion bridge. In contrast, the drug interacts with the human enzyme primarily through the C7 4-hydroxyphenyl ring and has no requirement for a substituent at C8 in order to attain high activity. Despite the fact that the human type II enzyme is unable to utilize the water-metal ion bridge, quinolones in the CP-115,955 series display higher activity against topoisomerase IIα in vitro and in cultured human cells than the corresponding quinazolinediones. Thus, quinolones may be a viable platform for the development of novel drugs with anticancer potential.
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Affiliation(s)
- Katie J Aldred
- Department of Biochemistry and ⊥Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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Drlica K, Mustaev A, Towle TR, Luan G, Kerns RJ, Berger JM. Bypassing fluoroquinolone resistance with quinazolinediones: studies of drug-gyrase-DNA complexes having implications for drug design. ACS Chem Biol 2014; 9:2895-904. [PMID: 25310082 PMCID: PMC4273985 DOI: 10.1021/cb500629k] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
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Widespread
fluoroquinolone resistance has drawn attention to quinazolinediones
(diones), fluoroquinolone-like topoisomerase poisons that are unaffected
by common quinolone-resistance mutations. To better understand differences
between quinolones and diones, we examined their impact on the formation
of cleaved complexes (drug–topoisomerase–DNA complexes
in which the DNA moiety is broken) with gyrase, one of two bacterial
targets of the drugs. Formation of cleaved complexes, measured by
linearization of a circular DNA substrate, required lower concentrations
of quinolone than dione. The reverse reaction, detected as resealing
of DNA breaks in cleaved complexes, required higher temperatures and
EDTA concentrations for quinolones than diones. The greater stability
of quinolone-containing complexes was attributed to the unique ability
of the quinolone C3/C4 keto acid to complex with magnesium and form
a previously described drug–magnesium–water bridge with
GyrA-Ser83 and GyrA-Asp87. A nearby substitution in GyrA (G81C) reduced
activity differences between quinolone and dione, indicating that
resistance due to this variation derives from perturbation of the
magnesium–water bridge. To increase dione activity, we examined
a relatively small, flexible C-7-3-(aminomethyl)pyrrolidinyl substituent,
which is distal to the bridging C3/C4 keto acid substituent of quinolones.
The 3-(aminomethyl)pyrrolidinyl group at position C-7 was capable
of forming binding interactions with GyrB-Glu466, as indicated by
inspection of crystal structures, computer-aided docking, and measurement
of cleaved-complex formation with mutant and wild-type GyrB proteins.
Thus, modification of dione C-7 substituents constitutes a strategy
for obtaining compounds active against common quinolone-resistant
mutants.
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Affiliation(s)
- Karl Drlica
- Public Health Research Institute and Department of Microbiology & Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Sciences, 225 Warren Street, Newark, New Jersey 07103, United States
| | - Arkady Mustaev
- Public Health Research Institute and Department of Microbiology & Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Sciences, 225 Warren Street, Newark, New Jersey 07103, United States
| | - Tyrell R. Towle
- Division of Medicinal & Natural Products Chemistry, Department of Pharmaceutical Sciences & Experimental Therapeutics, University of Iowa College of Pharmacy, 115 South Grand Avenue, Iowa City, Iowa 52246, United States
| | - Gan Luan
- Public Health Research Institute and Department of Microbiology & Molecular Genetics, New Jersey Medical School, Rutgers Biomedical and Health Sciences, 225 Warren Street, Newark, New Jersey 07103, United States
| | - Robert J. Kerns
- Division of Medicinal & Natural Products Chemistry, Department of Pharmaceutical Sciences & Experimental Therapeutics, University of Iowa College of Pharmacy, 115 South Grand Avenue, Iowa City, Iowa 52246, United States
| | - James M. Berger
- Molecular
and Cell Biology Department, Quantitative Biosciences Institute, University of California, Stanley Hall, Berkeley, California 94720, United States
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Aldred KJ, Breland EJ, Vlčková V, Strub MP, Neuman KC, Kerns RJ, Osheroff N. Role of the water-metal ion bridge in mediating interactions between quinolones and Escherichia coli topoisomerase IV. Biochemistry 2014; 53:5558-67. [PMID: 25115926 PMCID: PMC4151693 DOI: 10.1021/bi500682e] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
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Although
quinolones have been in clinical use for decades, the
mechanism underlying drug activity and resistance has remained elusive.
However, recent studies indicate that clinically relevant quinolones
interact with Bacillus anthracis (Gram-positive)
topoisomerase IV through a critical water–metal ion bridge
and that the most common quinolone resistance mutations decrease drug
activity by disrupting this bridge. As a first step toward determining
whether the water–metal ion bridge is a general mechanism of
quinolone–topoisomerase interaction, we characterized drug
interactions with wild-type Escherichia coli (Gram-negative)
topoisomerase IV and a series of ParC enzymes with mutations (S80L,
S80I, S80F, and E84K) in the predicted bridge-anchoring residues.
Results strongly suggest that the water–metal ion bridge is
essential for quinolone activity against E. coli topoisomerase
IV. Although the bridge represents a common and critical mechanism
that underlies broad-spectrum quinolone function, it appears to play
different roles in B. anthracis and E. coli topoisomerase IV. The water–metal ion bridge is the most
important binding contact of clinically relevant quinolones with the
Gram-positive enzyme. However, it primarily acts to properly align
clinically relevant quinolones with E. coli topoisomerase
IV. Finally, even though ciprofloxacin is unable to increase levels
of DNA cleavage mediated by several of the Ser80 and Glu84 mutant E. coli enzymes, the drug still retains the ability to inhibit
the overall catalytic activity of these topoisomerase IV proteins.
Inhibition parallels drug binding, suggesting that the presence of
the drug in the active site is sufficient to diminish DNA relaxation
rates.
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Affiliation(s)
- Katie J Aldred
- Department of Biochemistry and ‡Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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Abstract
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Quinolones
are one of the most commonly prescribed classes of antibacterials
in the world and are used to treat a variety of bacterial infections
in humans. Because of the wide use (and overuse) of these drugs, the
number of quinolone-resistant bacterial strains has been growing steadily
since the 1990s. As is the case with other antibacterial agents, the
rise in quinolone resistance threatens the clinical utility of this
important drug class. Quinolones act by converting their targets,
gyrase and topoisomerase IV, into toxic enzymes that fragment the
bacterial chromosome. This review describes the development of the
quinolones as antibacterials, the structure and function of gyrase
and topoisomerase IV, and the mechanistic basis for quinolone action
against their enzyme targets. It will then discuss the following three
mechanisms that decrease the sensitivity of bacterial cells to quinolones.
Target-mediated resistance is the most common and clinically significant
form of resistance. It is caused by specific mutations in gyrase and
topoisomerase IV that weaken interactions between quinolones and these
enzymes. Plasmid-mediated resistance results from extrachromosomal
elements that encode proteins that disrupt quinolone–enzyme
interactions, alter drug metabolism, or increase quinolone efflux.
Chromosome-mediated resistance results from the underexpression of
porins or the overexpression of cellular efflux pumps, both of which
decrease cellular concentrations of quinolones. Finally, this review
will discuss recent advancements in our understanding of how quinolones
interact with gyrase and topoisomerase IV and how mutations in these
enzymes cause resistance. These last findings suggest approaches to
designing new drugs that display improved activity against resistant
strains.
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Affiliation(s)
- Katie J Aldred
- Department of Biochemistry and ‡Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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Aldred KJ, Schwanz HA, Li G, McPherson SA, Turnbough CL, Kerns RJ, Osheroff N. Overcoming target-mediated quinolone resistance in topoisomerase IV by introducing metal-ion-independent drug-enzyme interactions. ACS Chem Biol 2013; 8:2660-8. [PMID: 24047414 DOI: 10.1021/cb400592n] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quinolones, which target gyrase and topoisomerase IV, are the most widely prescribed antibacterials worldwide. Unfortunately, their use is threatened by the increasing prevalence of target-mediated drug resistance. Greater than 90% of mutations that confer quinolone resistance act by disrupting enzyme-drug interactions coordinated by a critical water-metal ion bridge. Quinazolinediones are quinolone-like drugs but lack the skeletal features necessary to support the bridge interaction. These compounds are of clinical interest, however, because they retain activity against the most common quinolone resistance mutations. We utilized a chemical biology approach to determine how quinazolinediones overcome quinolone resistance in Bacillus anthracis topoisomerase IV. Quinazolinediones that retain activity against quinolone-resistant topoisomerase IV do so primarily by establishing novel interactions through the C7 substituent, rather than the drug skeleton. Because some quinolones are highly active against human topoisomerase IIα, we also determined how clinically relevant quinolones discriminate between the bacterial and human enzymes. Clinically relevant quinolones display poor activity against topoisomerase IIα because the human enzyme cannot support drug interactions mediated by the water-metal ion bridge. However, the inclusion of substituents that allow quinazolinediones to overcome topoisomerase IV-mediated quinolone resistance can cause cross-reactivity against topoisomerase IIα. Therefore, a major challenge in designing drugs that overcome quinolone resistance lies in the ability to identify substituents that mediate strong interactions with the bacterial, but not the human, enzymes. On the basis of our understanding of quinolone-enzyme interactions, we have identified three compounds that display high activity against quinolone-resistant B. anthracis topoisomerase IV but low activity against human topoisomerase IIα.
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Affiliation(s)
| | - Heidi A. Schwanz
- Division
of Medicinal and Natural Products Chemistry, University of Iowa College of Pharmacy, Iowa City, Iowa 52242, United States
| | - Gangqin Li
- Division
of Medicinal and Natural Products Chemistry, University of Iowa College of Pharmacy, Iowa City, Iowa 52242, United States
| | - Sylvia A. McPherson
- Department
of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Charles L. Turnbough
- Department
of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Robert J. Kerns
- Division
of Medicinal and Natural Products Chemistry, University of Iowa College of Pharmacy, Iowa City, Iowa 52242, United States
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20
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Shah Z, Mahbuba R, Turcotte B. The anticancer drug tirapazamine has antimicrobial activity against Escherichia coli, Staphylococcus aureus and Clostridium difficile. FEMS Microbiol Lett 2013; 347:61-9. [PMID: 23888874 DOI: 10.1111/1574-6968.12223] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 06/28/2013] [Accepted: 07/17/2013] [Indexed: 12/21/2022] Open
Abstract
Rapidly increasing bacterial resistance to existing therapies creates an urgent need for the development of new antibacterials. Tirapazamine (TPZ, 3-amino-1,2,4-benzotriazine 1,4 dioxide) is a prodrug undergoing clinical trials for various types of cancers. In this study, we showed that TPZ has antibacterial activity, particularly at low oxygen levels. With Escherichia coli, TPZ was bactericidal under both aerobic and anaerobic conditions. Escherichia coli mutants deficient in homologous recombination were hypersusceptible to TPZ, suggesting that drug toxicity may be due to DNA damage. Moreover, E. coli strains deleted for genes encoding putative reductases were resistant to TPZ, implying that these enzymes are responsible for conversion of the prodrug to a toxic compound. Fluoroquinolone-resistant E. coli strains were as susceptible to TPZ as a wild-type strain. Methicillin-resistant Staphylococcus aureus strains were also susceptible to TPZ (MIC = 0.5 μg mL(-1) ), as were pathogenic strains of Clostridium difficile (MIC = 7.5 ng mL(-1) ). TPZ may merit additional study as a broad-spectrum antibacterial, particularly for anaerobes.
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Affiliation(s)
- Zarna Shah
- Department of Biochemistry, McGill University, Montréal, QC, Canada
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21
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Aldred KJ, McPherson SA, Turnbough CL, Kerns RJ, Osheroff N. Topoisomerase IV-quinolone interactions are mediated through a water-metal ion bridge: mechanistic basis of quinolone resistance. Nucleic Acids Res 2013; 41:4628-39. [PMID: 23460203 PMCID: PMC3632122 DOI: 10.1093/nar/gkt124] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although quinolones are the most commonly prescribed antibacterials, their use is threatened by an increasing prevalence of resistance. The most common causes of quinolone resistance are mutations of a specific serine or acidic residue in the A subunit of gyrase or topoisomerase IV. These amino acids are proposed to serve as a critical enzyme-quinolone interaction site by anchoring a water-metal ion bridge that coordinates drug binding. To probe the role of the proposed water-metal ion bridge, we characterized wild-type, GrlAE85K, GrlAS81F/E85K, GrlAE85A, GrlAS81F/E85A and GrlAS81FBacillus anthracis topoisomerase IV, their sensitivity to quinolones and related drugs and their use of metal ions. Mutations increased the Mg2+ concentration required to produce maximal quinolone-induced DNA cleavage and restricted the divalent metal ions that could support quinolone activity. Individual mutation of Ser81 or Glu85 partially disrupted bridge function, whereas simultaneous mutation of both residues abrogated protein–quinolone interactions. Results provide functional evidence for the existence of the water-metal ion bridge, confirm that the serine and glutamic acid residues anchor the bridge, demonstrate that the bridge is the primary conduit for interactions between clinically relevant quinolones and topoisomerase IV and provide a likely mechanism for the most common causes of quinolone resistance.
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Affiliation(s)
- Katie J Aldred
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
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Induction of mycobacterial resistance to quinolone class antimicrobials. Antimicrob Agents Chemother 2012; 56:3879-87. [PMID: 22564842 DOI: 10.1128/aac.00474-12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An agar plate assay was developed for detecting the induction of drug-resistant mycobacterial mutants during exposure to inhibitors of DNA gyrase. When Mycobacterium smegmatis on drug-containing agar, resistant colonies arose over a period of 2 weeks. A recA deficiency reduced mutant recovery, consistent with involvement of the SOS response in mutant induction. The C-8-methoxy compounds gatifloxacin and moxifloxacin allowed the recovery of fewer resistant mutants than either ciprofloxacin or levofloxacin when present at the same multiple of the MIC; a quinolone-like 8-methoxy-quinazoline-2,4-dione was more effective at restricting the emergence of resistant mutants than its cognate fluoroquinolone. Thus, the structure of fluoroquinolone-like compounds affects mutant recovery. A spontaneous mutator mutant of M. smegmatis, obtained by growth in medium containing both isoniazid and rifampin, increased mutant induction during exposure to ciprofloxacin. Moreover, the mutator increased the size of spontaneous resistant mutant subpopulations, as detected by population analysis. Induction of ciprofloxacin resistance was also observed with Mycobacterium tuberculosis H37Rv. When measured with clinical isolates, no difference in mutant recovery was observed between multidrug-resistant (MDR) and pansusceptible isolates. This finding is consistent with at least some MDR isolates of M. tuberculosis lacking mutators detectable by the agar plate assay. Collectively, the data indicate that the use of fluoroquinolones against tuberculosis may induce resistance and that the choice of quinolone may be important for restricting the recovery of induced mutants.
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Aldred KJ, McPherson SA, Wang P, Kerns RJ, Graves DE, Turnbough CL, Osheroff N. Drug interactions with Bacillus anthracis topoisomerase IV: biochemical basis for quinolone action and resistance. Biochemistry 2011; 51:370-81. [PMID: 22126453 DOI: 10.1021/bi2013905] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Bacillus anthracis, the causative agent of anthrax, is considered a serious threat as a bioweapon. The drugs most commonly used to treat anthrax are quinolones, which act by increasing the levels of DNA cleavage mediated by topoisomerase IV and gyrase. Quinolone resistance most often is associated with specific serine mutations in these enzymes. Therefore, to determine the basis for quinolone action and resistance, we characterized wild-type B. anthracis topoisomerase IV, the GrlA(S81F) and GrlA(S81Y) quinolone-resistant mutants, and the effects of quinolones and a related quinazolinedione on these enzymes. Ser81 is believed to anchor a water-Mg(2+) bridge that coordinates quinolones to the enzyme through the C3/C4 keto acid. Consistent with this hypothesized bridge, ciprofloxacin required increased Mg(2+) concentrations to support DNA cleavage by GrlA(S81F) topoisomerase IV. The three enzymes displayed similar catalytic activities in the absence of drugs. However, the resistance mutations decreased the affinity of topoisomerase IV for ciprofloxacin and other quinolones, diminished quinolone-induced inhibition of DNA religation, and reduced the stability of the enzyme-quinolone-DNA ternary complex. Wild-type DNA cleavage levels were generated by mutant enzymes at high quinolone concentrations, suggesting that increased drug potency could overcome resistance. 8-Methyl-quinazoline-2,4-dione, which lacks the quinolone keto acid (and presumably does not require the water-Mg(2+) bridge to mediate protein interactions), was more potent than quinolones against wild-type topoisomerase IV and was equally efficacious. Moreover, it maintained high potency and efficacy against the mutant enzymes, effectively inhibited DNA religation, and formed stable ternary complexes. Our findings provide an underlying biochemical basis for the ability of quinazolinediones to overcome clinically relevant quinolone resistance mutations in bacterial type II topoisomerases.
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Affiliation(s)
- Katie J Aldred
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States
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Marks KR, Malik M, Mustaev A, Hiasa H, Drlica K, Kerns RJ. Synthesis and evaluation of 1-cyclopropyl-2-thioalkyl-8-methoxy fluoroquinolones. Bioorg Med Chem Lett 2011; 21:4585-8. [PMID: 21705218 DOI: 10.1016/j.bmcl.2011.05.112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 05/27/2011] [Accepted: 05/27/2011] [Indexed: 01/22/2023]
Abstract
Novel fluoroquinolone derivatives substituted with a 2-thioalkyl moiety, with and without a concomitant 3-carboxylate group, were synthesized to evaluate the effect of C-2 thioalkyl substituents on gyrase binding and inhibition. The presence of a 2-thioalkyl group universally decreased activity as compared to parent fluoroquinolones. However, with derivatives of moxifloxacin the presence of either a 2-thioalkyl group or a 3-carboxylate moiety increased activity over the 2,3-unsubstituted derivative. Energy minimization of structures provides an explanation for relative activities of fluoroquinolones having a C-2 thio moiety.
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Affiliation(s)
- Kevin R Marks
- Division of Medicinal and Natural Products Chemistry, University of Iowa College of Pharmacy, Iowa City, IA 52242, USA
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25
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Fluoroquinolone and quinazolinedione activities against wild-type and gyrase mutant strains of Mycobacterium smegmatis. Antimicrob Agents Chemother 2011; 55:2335-43. [PMID: 21383100 DOI: 10.1128/aac.00033-11] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Quinazolinediones (diones) are fluoroquinolone-like inhibitors of bacterial gyrase and DNA topoisomerase IV. To assess activity against mycobacteria, C-8-methoxy dione derivatives were compared with cognate fluoroquinolones by using cultured Mycobacterium smegmatis. Diones exhibited higher MIC values than fluoroquinolones; however, MICs for fluoroquinolone-resistant gyrA mutants, normalized to the MIC for wild-type cells, were lower. Addition of a 3-amino group to the 2,4-dione core increased relative activity against mutants, while alteration of the 8-methoxy group to a methyl or of the 2,4-dione core to a 1,3-dione core lowered activity against mutants. A GyrA G89C bacterial variant was strikingly susceptible to most of the diones tested; in contrast, low susceptibility to fluoroquinolones was observed. Many of the bacteriostatic differences between diones and fluoroquinolones were explained by interactions at the N terminus of GyrA helix IV revealed by recently published X-ray structures of drug-topoisomerase-DNA complexes. When lethal activity was normalized to the MIC in order to minimize the effects of drug uptake, efflux, and ternary complex formation, a 3-amino-2,4-dione exhibited killing activity comparable to that of a cognate fluoroquinolone. Surprisingly, the lethal activity of the dione was inhibited less by chloramphenicol than that of the cognate fluoroquinolone. This observation adds the 2,4-dione structural motif to the list of structural features known to impart lethality to fluoroquinolone-like compounds in the absence of protein synthesis, a phenomenon that is not explained by X-ray structures of drug-enzyme-DNA complexes.
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Wiles JA, Bradbury BJ, Pucci MJ. New quinolone antibiotics: a survey of the literature from 2005 to 2010. Expert Opin Ther Pat 2010; 20:1295-319. [DOI: 10.1517/13543776.2010.505922] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Dartois V, Barry CE. Clinical pharmacology and lesion penetrating properties of second- and third-line antituberculous agents used in the management of multidrug-resistant (MDR) and extensively-drug resistant (XDR) tuberculosis. CURRENT CLINICAL PHARMACOLOGY 2010; 5:96-114. [PMID: 20156156 PMCID: PMC6344931 DOI: 10.2174/157488410791110797] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 12/17/2009] [Indexed: 11/22/2022]
Abstract
Failure of first-line chemotherapy to cure tuberculosis (TB) patients occurs, in part, because of the development of resistance to isoniazid (INH) and rifampicin (RIF) the two most sterilizing agents in the four-drug regimen used to treat primary infections. Strains resistant to both INH and RIF are termed multidrug-resistant (MDR). Treatment options for MDR patients involve a complex array of twenty different drugs only two classes of which are considered to be highly effective (fluoroquinolones and aminoglycosides). Resistance to these two classes results in strains known as extensively drug-resistant (XDR) and these types of infections are becoming increasingly common. Many of the remaining agents have poorly defined pharmacology but nonetheless are widely used in the treatment of this disease. Several of these agents are known to have highly variable exposures in healthy volunteers and little is known in the patients in which they must be used. Therapeutic drug monitoring (TDM) is infrequently used in the management of MDR or XDR disease yet the clinical pharmacokinetic studies that have been done suggest this might have a large impact on disease outcome. We review what is known about the pharmacologic properties of each of the major classes of second- and third-line antituberculosis agents and suggest where judicious use of TDM would have the maximum possible impact. We summarize the state of knowledge of drug-drug interactions (DDI) in these classes of agents and those that are currently in clinical trials. Finally we consider what little is known about the ability of TB drugs to reach their ultimate site of action--the interior of a granuloma by penetrating the diseased lung area. Careful consideration of the pharmacology of these agents is essential if we are to avoid further fueling the growing epidemic of highly drug-resistant TB and critical in the development of new antituberculosis drugs.
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Affiliation(s)
- Véronique Dartois
- The Novartis Institute for Tropical Diseases, Biopolis, Singapore, Singapore.
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Comparison of in vitro activities of fluoroquinolone-like 2,4- and 1,3-diones. Antimicrob Agents Chemother 2010; 54:3011-4. [PMID: 20404126 DOI: 10.1128/aac.00190-10] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial resistance presents a difficult issue for fluoroquinolone treatment of bacterial infections. In previous work, we reported that 8-methoxy-quinazoline-2,4-diones are active against quinolone-resistant mutants of Escherichia coli. Here, we demonstrate the activity of a representative 8-methoxy-quinazoline-2,4-dione against quinolone-resistant gyrases. Furthermore, 8-methoxy-quinazoline-2,4-dione and other diones are shown to inhibit Staphylococcus aureus gyrase and topoisomerase IV with similar degrees of efficacy, suggesting that the diones might act as dual-targeting agents against S. aureus.
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Novel approach for comparing the abilities of quinolones to restrict the emergence of resistant mutants during quinolone exposure. Antimicrob Agents Chemother 2009; 54:149-56. [PMID: 19805561 DOI: 10.1128/aac.01035-09] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
An agar-plate assay was adapted to examine aspects of quinolone structure that restrict the emergence of quinolone-mediated quinolone resistance. When Escherichia coli was applied to agar containing nalidixic acid, the number of quinolone-resistant mutants arising during incubation was decreased by raising the drug concentration and by mutations expected to block the induction of the SOS response (recA, lexA); the mutant number was increased by a mutator mutation (ung). The examination of four related fluoroquinolones then revealed that a C-8 methoxy group and an N-ethyl piperazine substituent at C-7 reduced mutant acquisition more effectively than C-8 H and C-7 C-ethyl piperazine groups. The fluoroquinolone that was most effective at restricting mutant acquisition was the most active when lethal activity was measured on agar plates or in liquid medium (as minimal bactericidal concentration). It also exhibited the lowest ratio of mutant MIC to wild-type MIC when it was tested with a set of isogenic gyrase mutants, and it had a low mutant prevention concentration (MPC) relative to MIC. However, a low MPC was less likely to be important in restricting the induced mutant accumulation because a fluoroquinolone N-ethyl piperazine substituent was more effective than a C-ethyl piperazine substituent at reducing mutant accumulation but was less effective at lowering the MPC. An 8-methoxy-quinazoline-2,4-dione was also effective at restricting the accumulation of resistant mutants on agar. Collectively, these data characterize a simple assay for detection of drug-mediated resistance that is sensitive to the structures of GyrA inhibitors. The assay provides a new method for screening quinolones and quinolone-like molecules that complements MPC-based tests for restricting the emergence of resistance.
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Probing the differential interactions of quinazolinedione PD 0305970 and quinolones with gyrase and topoisomerase IV. Antimicrob Agents Chemother 2009; 53:3822-31. [PMID: 19564360 DOI: 10.1128/aac.00113-09] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Quinazoline-2,4-diones, such as PD 0305970, are new DNA gyrase and topoisomerase IV (topo IV) inhibitors with potent activity against gram-positive pathogens, including quinolone-resistant isolates. The mechanistic basis of dione activity vis-à-vis quinolones is not understood. We present evidence for Streptococcus pneumoniae gyrase and topo IV that PD 0305970 and quinolones interact differently with the enzyme breakage-reunion and Toprim domains, DNA, and Mg2+-four components that are juxtaposed in the topoisomerase cleavage complex to effect DNA scission. First, PD 0305970 targets primarily gyrase in Streptococcus pneumoniae. However, unlike quinolones, which select predominantly for gyrA (or topo IV parC) mutations in the breakage-reunion domain, unusually the dione selected for novel mutants with alterations that map to a region of the Toprim domain of GyrB (R456H and E474A or E474D) or ParE (D435H and E475A). This "dione resistance-determining region" overlaps the GyrB quinolone resistance-determining region and the region that binds essential Mg2+ ions, each function involving conserved EGDSA and PLRGK motifs. Second, dione-resistant gyrase and topo IV were inhibited by ciprofloxacin, whereas quinolone-resistant enzymes (GyrA S81F and ParC S79F) remained susceptible to PD 0305970. Third, dione-promoted DNA cleavage by gyrase occurred at a distinct repertoire of sites, implying that structural differences with quinolones are sensed at the DNA level. Fourth, unlike the situation with quinolones, the Mg2+ chelator EDTA did not reverse dione-induced gyrase cleavage nor did the dione promote Mg2+-dependent DNA unwinding. It appears that PD 0305970 interacts uniquely to stabilize the cleavage complex of gyrase/topo IV perhaps via an altered orientation directed by the bidentate 3-amino-2,4-dione moiety.
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Rosen JD, German N, Kerns RJ. Efficient Synthesis of the 2-amino-6-chloro-4-cyclopropyl-7-fluoro-5-methoxy-pyrido[1,2-c]pyrimidine-1,3-dione core ring system. Tetrahedron Lett 2009; 50:785-789. [PMID: 20160840 DOI: 10.1016/j.tetlet.2008.11.121] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
An optimized total synthesis of the 2-amino-6-chloro-4-cyclopropyl-7-fluoro-5-methoxy-pyrido[1,2-c]pyrimidine-1,3-dione core structure of a new fluoroquinolone-like class of antibacterial agents is described. This synthesis is highlighted by a nearly quantitative ring-closing reaction to form the pyrido[1,2-c]pyrimidine core. This bicyclic ring system serves as a scaffold for a family of biologically active compounds.
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Affiliation(s)
- Jonathan D Rosen
- Division of Medicinal & Natural Products Chemistry, University of Iowa, Iowa City, Iowa 52242, USA
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Drlica K, Hiasa H, Kerns R, Malik M, Mustaev A, Zhao X. Quinolones: action and resistance updated. Curr Top Med Chem 2009; 9:981-98. [PMID: 19747119 PMCID: PMC3182077 DOI: 10.2174/156802609789630947] [Citation(s) in RCA: 235] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 07/30/2009] [Indexed: 11/22/2022]
Abstract
The quinolones trap DNA gyrase and DNA topoisomerase IV on DNA as complexes in which the DNA is broken but constrained by protein. Early studies suggested that drug binding occurs largely along helix-4 of the GyrA (gyrase) and ParC (topoisomerase IV) proteins. However, recent X-ray crystallography shows drug intercalating between the -1 and +1 nucleotides of cut DNA, with only one end of the drug extending to helix-4. These two models may reflect distinct structural steps in complex formation. A consequence of drug-enzyme-DNA complex formation is reversible inhibition of DNA replication; cell death arises from subsequent events in which bacterial chromosomes are fragmented through two poorly understood pathways. In one pathway, chromosome fragmentation stimulates excessive accumulation of highly toxic reactive oxygen species that are responsible for cell death. Quinolone resistance arises stepwise through selective amplification of mutants when drug concentrations are above the MIC and below the MPC, as observed with static agar plate assays, dynamic in vitro systems, and experimental infection of rabbits. The gap between MIC and MPC can be narrowed by compound design that should restrict the emergence of resistance. Resistance is likely to become increasingly important, since three types of plasmid-borne resistance have been reported.
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Affiliation(s)
- Karl Drlica
- Public Health Research Institute, New Jersey Medical School, UMDNJ, 225 Warren Street, Newark, NJ 07103, USA.
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