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Głowacka IE, Gawron K, Piotrowska DG, Graus M, Andrei G, Schols D, Snoeck R, Camps A, Vanhulle E, Vermeire K. Design and synthesis of a new series of hybrids of functionalised N 1-[(1H-1,2,3-triazol-4-yl)methyl]quinazoline-2,4-dione with antiviral activity against Respiratory Syncytial Virus. Antiviral Res 2023; 209:105518. [PMID: 36587900 DOI: 10.1016/j.antiviral.2022.105518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/20/2022] [Accepted: 12/26/2022] [Indexed: 12/31/2022]
Abstract
In this study, a series of 48 hybrids of the functionalised 1-[(1H-1,2,3-triazole-4-yl)methyl]quinazoline-2,4-dione 17-22 were synthesised and evaluated for potential antiviral activity. The new hybrids were designed to contain a diethoxyphosphoryl group connected to the triazole moiety via ethylene or propylene linker, and in which the benzyl or benzoyl function is substituted at N3 in the quinazoline-2,4-dione moiety. The Cu(I)-catalyzed Hüisgen dipolar cycloaddition of azidophosphonates 23 and 24 with the respective N1-propargylquinazoline-2,4-diones 26aa-26ag, 26ba-26bg, 27aa-27ad and 27ba-27bd was applied for the syntheses of the designed compounds. All final hybrids 17-22 and N3-functionalised N1-propargylquinazoline-2,4-diones 26 and 27 were subsequently evaluated for their antiviral activity toward a broad range of DNA and RNA viruses. Importantly, hybrids 19be-19bg and 20be-20bg showed profound antiviral activities against Respiratory Syncytial Virus (RSV) with EC50 values in the lower micromolar range, with activity against viral strains of both subtypes (RSV A and B). In addition, several compounds also exerted some weak antiviral activity against varicella zoster virus. Finally, 19 ag was the only compound that showed antiviral potency against human cytomegalovirus, although with rather weak inhibitory activity. Notably, none of the tested compounds was cytotoxic toward uninfected cell lines used for the antiviral assays at a concentration up to 100 μM, returning interesting therapeutic indices for respiratory syncytial virus.
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Affiliation(s)
- Iwona E Głowacka
- Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Lodz, 90-151, Lodz, Muszyńskiego 1, Poland.
| | - Katarzyna Gawron
- Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Lodz, 90-151, Lodz, Muszyńskiego 1, Poland
| | - Dorota G Piotrowska
- Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Lodz, 90-151, Lodz, Muszyńskiego 1, Poland
| | - Mirthe Graus
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
| | - Graciela Andrei
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
| | - Dominique Schols
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
| | - Robert Snoeck
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
| | - Anita Camps
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
| | - Emiel Vanhulle
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
| | - Kurt Vermeire
- KU Leuven Department of Microbiology, Immunology and Transplantation, Rega Institute, Laboratory of Virology and Chemotherapy, Herestraat 49, Box 1030, B-3000, Leuven, Belgium
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2
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Łysakowska M, Głowacka IE, Andrei G, Schols D, Snoeck R, Lisiecki P, Szemraj M, Piotrowska DG. Design, Synthesis, Anti-Varicella-Zoster and Antimicrobial Activity of (Isoxazolidin-3-yl)Phosphonate Conjugates of N1-Functionalised Quinazoline-2,4-Diones. Molecules 2022; 27:molecules27196526. [PMID: 36235061 PMCID: PMC9571433 DOI: 10.3390/molecules27196526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 09/26/2022] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
Dipolar cycloaddition of the N-substituted C-(diethoxyphosphonyl)nitrones with N3-allyl-N1-benzylquinazoline-2,4-diones produced mixtures of diastereoisomeric 3-(diethoxyphosphonyl)isoxazolidines with a N1-benzylquinazoline-2,4-dione unit at C5. The obtained compounds were assessed for antiviral and antibacterial activities. Several compounds showed moderate inhibitory activities against VZV with EC50 values in the range of 12.63-58.48 µM. A mixture of isoxazolidines cis-20c/trans-20c (6:94) was found to be the most active against B. cereus PCM 1948, showing an MIC value 0.625 mg/mL, and also was not mutagenic up to this concentration.
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Affiliation(s)
- Magdalena Łysakowska
- Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Lodz, Muszynskiego 1, 90-151 Lodz, Poland
| | - Iwona E. Głowacka
- Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Lodz, Muszynskiego 1, 90-151 Lodz, Poland
| | - Graciela Andrei
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, B-3000 Leuven, Belgium
| | - Dominique Schols
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, B-3000 Leuven, Belgium
| | - Robert Snoeck
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, B-3000 Leuven, Belgium
| | - Paweł Lisiecki
- Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Faculty of Pharmacy, Medical University of Lodz, Muszynskiego 1, 90-151 Lodz, Poland
| | - Magdalena Szemraj
- Department of Pharmaceutical Microbiology and Microbiological Diagnostics, Faculty of Pharmacy, Medical University of Lodz, Muszynskiego 1, 90-151 Lodz, Poland
| | - Dorota G. Piotrowska
- Bioorganic Chemistry Laboratory, Faculty of Pharmacy, Medical University of Lodz, Muszynskiego 1, 90-151 Lodz, Poland
- Correspondence:
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Salman M, Sharma P, Kumar M, Ethayathulla AS, Kaur P. Targeting novel sites in DNA gyrase for development of anti-microbials. Brief Funct Genomics 2022; 22:180-194. [PMID: 36064602 DOI: 10.1093/bfgp/elac029] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 07/28/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Antimicrobial resistance in bacteria poses major challenges in selection of the therapeutic regime for managing the infectious disease. There is currently an upsurge in the appearance of multiple drug resistance in bacterial pathogens and a decline in the discovery of novel antibiotics. DNA gyrase is an attractive target used for antibiotic discovery due to its vital role in bacterial DNA replication and segregation in addition to its absence in mammalian organisms. Despite the presence of successful antibiotics targeting this enzyme, there is a need to bypass the resistance against this validated drug target. Hence, drug development in DNA gyrase is a highly active research area. In addition to the conventional binding sites for the novobiocin and fluoroquinolone antibiotics, several novel sites are being exploited for drug discovery. The binding sites for novel bacterial type II topoisomerase inhibitor (NBTI), simocyclinone, YacG, Thiophene and CcdB are structurally and biochemically validated active sites, which inhibit the supercoiling activity of topoisomerases. The novel chemical moieties with varied scaffolds have been identified to target DNA gyrase. Amongst them, the NBTI constitutes the most advanced DNA gyrase inhibitor which are in phase III trial of drug development. The present review aims to classify the novel binding sites other than the conventional novobiocin and quinolone binding pocket to bypass the resistance due to mutations in the DNA gyrase enzyme. These sites can be exploited for the identification of new scaffolds for the development of novel antibacterial compounds.
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Affiliation(s)
- Mohd Salman
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Priyanka Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Mukesh Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - A S Ethayathulla
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Punit Kaur
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi 110029, India
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4
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Pudipeddi A, Vasudevan S, Shanmugam K, Mohan S S, Vairaprakash P, Neelakantan P, Balraj AS, Solomon AP. Design, dynamic docking, synthesis, and in vitro validation of a novel DNA gyrase B inhibitor. J Biomol Struct Dyn 2022:1-14. [PMID: 35924774 DOI: 10.1080/07391102.2022.2107073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-intermediate-resistant Staphylococcus aureus (VRSA) are among the WHO's high priority pathogens. Among these two, MRSA is the most globally documented pathogen that necessitates the pressing demand for new classes of anti-MRSA drugs. Bacterial gyrase targeted therapeutics are unique strategies to overcome cross-resistance as they are present only in bacteria and absent in higher eukaryotes. The GyrB subunit is essential for the catalytic functions of the bacterial enzyme DNA Gyrase, thereby constituting a promising druggable target. The current study performed a structure-based virtual screening to designing GyrB target-specific candidate molecules. The de novo ligand design of novel hit molecules was performed using a rhodanine scaffold. Through a systematic in silico screening process, the hit molecules were screened for their synthetic accessibility, drug-likeness and pharmacokinetics properties in addition to its target specific interactions. Of the 374 hit molecules obtained through de novo ligand design, qsl-304 emerged as the most promising ligand. The molecular dynamic simulation studies confirmed the stable interaction between the key residues and qsl-304. qsl-304 was synthesized through a one-step chemical synthesis procedure, and the in vitro activity was proven, with an IC50 of 31.23 µg/mL against the novobiocin resistant clinical isolate, Staphylococcus aureus sa-P2003. Further studies on time-kill kinetics showed the bacteriostatic nature with the diminished recurrence of resistance. The on-target gyrB inhibition further proved the efficacy of qsl-304.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Akhila Pudipeddi
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India.,Faculty of Dentistry, The University of Hong Kong, Pok Fu Lam, Hong Kong
| | - Sahana Vasudevan
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Karthi Shanmugam
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India.,Department of Bioinformatics, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Suma Mohan S
- Department of Bioinformatics, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Pothiappan Vairaprakash
- Department of Chemistry, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | | | - Alex Stanley Balraj
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India.,Department of Bioinformatics, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
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5
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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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6
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Allele-specific collateral and fitness effects determine the dynamics of fluoroquinolone resistance evolution. Proc Natl Acad Sci U S A 2022; 119:e2121768119. [PMID: 35476512 PMCID: PMC9170170 DOI: 10.1073/pnas.2121768119] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A promising strategy to overcome the evolution of antibiotic-resistant bacteria is to use collateral sensitivity-informed antibiotic treatments that rely on cycling or mixing of antibiotics, such that that resistance toward one antibiotic confers increased sensitivity to the other. Here, focusing on multistep fluoroquinolone resistance in Streptococcus pneumoniae, we show that antibiotic resistance induces diverse collateral responses whose magnitude and direction are determined by allelic identity. Using mathematical simulations, we show that these effects can be exploited via combination treatment regimens to suppress the de novo emergence of resistance during treatment. Collateral sensitivity (CS), which arises when resistance to one antibiotic increases sensitivity toward other antibiotics, offers treatment opportunities to constrain or reverse the evolution of antibiotic resistance. The applicability of CS-informed treatments remains uncertain, in part because we lack an understanding of the generality of CS effects for different resistance mutations, singly or in combination. Here, we address this issue in the gram-positive pathogen Streptococcus pneumoniae by measuring collateral and fitness effects of clinically relevant gyrA and parC alleles and their combinations that confer resistance to fluoroquinolones. We integrated these results in a mathematical model that allowed us to evaluate how different in silico combination treatments impact the dynamics of resistance evolution. We identified common and conserved CS effects of different gyrA and parC alleles; however, the spectrum of collateral effects was unique for each allele or allelic pair. This indicated that allelic identity can impact the evolutionary dynamics of resistance evolution during monotreatment and combination treatment. Our model simulations, which included the experimentally derived antibiotic susceptibilities and fitness effects, and antibiotic-specific pharmacodynamics revealed that both collateral and fitness effects impact the population dynamics of resistance evolution. Overall, we provide evidence that allelic identity and interactions can have a pronounced impact on collateral effects to different antibiotics and suggest that these need to be considered in models examining CS-based therapies.
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7
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Gheidari D, Mehrdad M, Maleki S. Recent Advances in Synthesis of Quinazoline‐2,4(
1H,3H
)‐diones: Versatile Building Blocks in
N
‐ Heterocyclic Compounds. Appl Organomet Chem 2022. [DOI: 10.1002/aoc.6631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Davood Gheidari
- Department of Chemistry, Faculty of Science University of Guilan Rasht Iran
| | - Morteza Mehrdad
- Department of Chemistry, Faculty of Science University of Guilan Rasht Iran
| | - Saloomeh Maleki
- Department of Chemistry, Faculty of Science University of Shahrood Iran
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8
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Kirk R, Ratcliffe A, Noonan G, Uosis-Martin M, Lyth D, Bardell-Cox O, Massam J, Schofield P, Hindley S, Jones DR, Maclean J, Smith A, Savage V, Mohmed S, Charrier C, Salisbury AM, Moyo E, Metzger R, Chalam-Judge N, Cheung J, Stokes NR, Best S, Craighead M, Armer R, Huxley A. Rational design, synthesis and testing of novel tricyclic topoisomerase inhibitors for the treatment of bacterial infections part 1. RSC Med Chem 2020; 11:1366-1378. [PMID: 34095844 DOI: 10.1039/d0md00174k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 08/07/2020] [Indexed: 12/17/2022] Open
Abstract
The alarming reduction in drug effectiveness against bacterial infections has created an urgent need for the development of new antibacterial agents that circumvent bacterial resistance mechanisms. We report here a series of DNA gyrase and topoisomerase IV inhibitors that demonstrate potent activity against a range of Gram-positive and selected Gram-negative organisms, including clinically-relevant and drug-resistant strains. In part 1, we present a detailed structure activity relationship (SAR) analysis that led to the discovery of our previously disclosed compound, REDX05931, which has a minimum inhibitory concentration (MIC) of 0.06 μg mL-1 against fluoroquinolone-resistant Staphylococcus aureus. Although in vitro hERG and CYP inhibition precluded further development, it validates a rational design approach to address this urgent unmet medical need and provides a scaffold for further optimisation, which is presented in part 2.
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Affiliation(s)
- R Kirk
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - A Ratcliffe
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - G Noonan
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - M Uosis-Martin
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - D Lyth
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - O Bardell-Cox
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - J Massam
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - P Schofield
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - S Hindley
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - D R Jones
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - J Maclean
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - A Smith
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - V Savage
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - S Mohmed
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - C Charrier
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - A-M Salisbury
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - E Moyo
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - R Metzger
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - N Chalam-Judge
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - J Cheung
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - N R Stokes
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - S Best
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - M Craighead
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - R Armer
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
| | - A Huxley
- Redx Anti-Infectives Ltd, Alderley Park, Mereside Macclesfield SK10 4TG UK
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Ligand-based pharmacophore modelling, in silico virtual screening, molecular docking and molecular dynamic simulation study to identify novel Francisella tularensis ParE inhibitors. CHEMICAL PAPERS 2020. [DOI: 10.1007/s11696-020-01274-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Sharma P, Kumar M, Dahiya S, Sood S, Das BK, Kaur P, Kapil A. Structure based drug discovery and in vitro activity testing for DNA gyrase inhibitors of Salmonella enterica serovar Typhi. Bioorg Chem 2020; 104:104244. [PMID: 32966903 DOI: 10.1016/j.bioorg.2020.104244] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/23/2020] [Accepted: 08/25/2020] [Indexed: 11/24/2022]
Abstract
The emerged resistance in Typhoidal Salmonella has limited the treatment options for typhoid fever. In this scenario, there is a need to find alternate treatment modalities against this pathogen. Amongst the therapeutic agents currently being used to treat enteric fever, quinolones have enjoyed considerable success since past three decades. These drugs act upon DNA gyrase and the acquired resistance is due to mutations at Ser83 and Asp87 of gyrase A subunit. In the present study DNA gyrase enzyme was targeted to seek out potential new inhibitors which are not affected by these mutations. Molecular modelling and docking studies were performed in Schrödinger's molecular modelling software. Homology model of DNA gyrase-DNA complex was built using templates 1AB4 and 3LTN. Molecular dynamic simulations were performed in SPC solvent for 100 ns. Total 17,900,742 drug like molecules were downloaded from ZINC library of chemical compounds. The Glide XP score of the compounds ranged from -5.285 to -13.692. All the ligands bound at the four base pair staggered nick in the DNA binding groove of DNA gyrase enzyme with their aromatic rings intercalating between the bases of two successive nucleotides stabilized by π - π stacking interactions. The binding pocket of DNA gyrase B comprising conserved residues Lys 447, Gly 448, Lys 449, Ile 450, Leu 451, Gln 465 and Val 467 interacts with the ligand molecules through van der Waals interactions. The MIC (minimum inhibitory concentration), MBC (minimum bactericidal concentration) and IC50 of the tested compounds ranged from 500 to 125 mg/L, 750 to 500 mg/L and 100 to 12.5 mg/L, respectively. The selected hits bind to quinolone binding pocket, but their mode of binding and conformation is different to fluoroquinolones, and hence, their binding is not affected by mutations at Ser83 or Asp87 positions. These lead compounds can be further explored as a scaffold to design inhibitors against DNA gyrase to bypass quinolone resistance.
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Affiliation(s)
- Priyanka Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Manoj Kumar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Sushila Dahiya
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi, India
| | - Seema Sood
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi, India
| | - Bimal Kumar Das
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi, India
| | - Punit Kaur
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
| | - Arti Kapil
- Department of Microbiology, All India Institute of Medical Sciences, New Delhi, India.
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11
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Bientinesi R, Murri R, Sacco E. Efficacy and safety of levofloxacin as a treatment for complicated urinary tract infections and pyelonephritis. Expert Opin Pharmacother 2020; 21:637-644. [PMID: 32004097 DOI: 10.1080/14656566.2020.1720647] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Urinary tract infections (UTIs) are among the most common causes of sepsis presenting to hospitals. Treating complicated UTIs is extremely important due to their potential mortality. Levofloxacin is a fluoroquinolone antibacterial that has become one of the cornerstones of antibiotic therapy of complicated UTIs and pyelonephritis since its introduction in the 1990s because of its exceptional pharmacokinetic (PK) and pharmacodynamic (PD) profile. However, the emergence of widespread fluoroquinolone resistance over the past decade has prompted investigators to reexamine its place in the treatment of UTI. AREAS COVERED This literature review summarizes data about the efficacy and the tolerability of levofloxacin in treating complicated UTIs and pyelonephritis. EXPERT OPINION In the early 2000s, fluoroquinolones became the most commonly prescribed antibiotic in the US. Since then, the resistance rate of Escherichia coli to fluoroquinolones has increased, largely hampering the use of this class of drugs. These data, in association with emerging data about inappropriate prescription and toxicity, have limited its clinical use. For these reasons, a judicious use of levofloxacin and other fluoroquinolones and a careful implementation of infection control procedures are the main available tools for the management of UTIs and pyelonephritis.
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Affiliation(s)
- Riccardo Bientinesi
- Urology Department, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica Del Sacro Cuore , Rome, Italy
| | - Rita Murri
- Infective Disease Department, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica Del Sacro Cuore , Rome, Italy
| | - Emilio Sacco
- Urology Department, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica Del Sacro Cuore , Rome, Italy
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12
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Teng P, Li C, Peng Z, Anne Marie V, Nimmagadda A, Su M, Li Y, Sun X, Cai J. Facilely accessible quinoline derivatives as potent antibacterial agents. Bioorg Med Chem 2018; 26:3573-3579. [PMID: 29858158 DOI: 10.1016/j.bmc.2018.05.031] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/14/2018] [Accepted: 05/21/2018] [Indexed: 01/22/2023]
Abstract
Quinoline compounds have been extensively explored as anti-malaria and anti-cancer agents for decades and show profound functional bioactivities, however, the studies of these compounds in other medicinal fields have lagged dramatically. In this study, we report the development of a series of facilely accessible quinoline derivatives that display potent antibacterial activity against a panel of multidrug-resistant Gram-positive bacterial strains, especially C. difficile. We also demonstrated that these molecules are effective in vivo against C. difficile. These results revealed that these types of quinoline compounds could serve as prototypes for the development of an appealing class of antibiotic agents used to combat Gram-positive drug-resistant bacterial strains, including C. difficile.
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Affiliation(s)
- Peng Teng
- Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Chunhui Li
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Down Blvd, Tampa, FL 33612, USA; Department of Infection Control Center of Xiangya Hospital, Central South University, Changsha 410008, China
| | - Zhong Peng
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Down Blvd, Tampa, FL 33612, USA; State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Vanderschouw Anne Marie
- Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Alekhya Nimmagadda
- Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Ma Su
- Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Yaqiong Li
- Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Xingmin Sun
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Down Blvd, Tampa, FL 33612, USA.
| | - Jianfeng Cai
- Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA.
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Molecular insights on analogs of imidazo[1,2-a]pyridine, azaindole, and pyridylurea towards ParE using pharmacophore modeling, molecular docking, and dynamic simulation. Struct Chem 2017. [DOI: 10.1007/s11224-017-0919-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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14
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Gomes C, Martínez-Puchol S, Ruiz-Roldán L, Pons MJ, Del Valle Mendoza J, Ruiz J. Development and characterisation of highly antibiotic resistant Bartonella bacilliformis mutants. Sci Rep 2016; 6:33584. [PMID: 27667026 PMCID: PMC5035977 DOI: 10.1038/srep33584] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 08/31/2016] [Indexed: 01/31/2023] Open
Abstract
The objective was to develop and characterise in vitro Bartonella bacilliformis antibiotic resistant mutants. Three B. bacilliformis strains were plated 35 or 40 times with azithromycin, chloramphenicol, ciprofloxacin or rifampicin discs. Resistance-stability was assessed performing 5 serial passages without antibiotic pressure. MICs were determined with/without Phe-Arg-β-Napthylamide and artesunate. Target alterations were screened in the 23S rRNA, rplD, rplV, gyrA, gyrB, parC, parE and rpoB genes. Chloramphenicol and ciprofloxacin resistance were the most difficult and easiest (>37.3 and 10.6 passages) to be selected, respectively. All mutants but one selected with chloramphenicol achieved high resistance levels. All rifampicin, one azithromycin and one ciprofloxacin mutants did not totally revert when cultured without antibiotic pressure. Azithromycin resistance was related to L4 substitutions Gln-66 → Lys or Gly-70 → Arg; L4 deletion Δ62–65 (Lys-Met-Tyr-Lys) or L22 insertion 83::Val-Ser-Glu-Ala-His-Val-Gly-Lys-Ser; in two chloramphenicol-resistant mutants the 23S rRNA mutation G2372A was detected. GyrA Ala-91 → Val and Asp-95 → Gly and GyrB Glu474 → Lys were detected in ciprofloxacin-resistant mutants. RpoB substitutions Gln-527 → Arg, His-540 → Tyr and Ser-545 → Phe plus Ser-588 → Tyr were detected in rifampicin-resistant mutants. In 5 mutants the effect of efflux pumps on resistance was observed. Antibiotic resistance was mainly related to target mutations and overexpression of efflux pumps, which might underlie microbiological failures during treatments.
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Affiliation(s)
- Cláudia Gomes
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Sandra Martínez-Puchol
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Lidia Ruiz-Roldán
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Maria J Pons
- School of Medicine, Research Center and Innovation of the Health Sciences Faculty, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru
| | - Juana Del Valle Mendoza
- School of Medicine, Research Center and Innovation of the Health Sciences Faculty, Universidad Peruana de Ciencias Aplicadas (UPC), Lima, Peru.,Instituto de Investigación Nutricional, Lima, Peru
| | - Joaquim Ruiz
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
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15
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Ultra-high performance liquid chromatographic determination of levofloxacin in human plasma and prostate tissue with use of experimental design optimization procedures. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1029-1030:48-59. [DOI: 10.1016/j.jchromb.2016.06.051] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 06/25/2016] [Accepted: 06/28/2016] [Indexed: 11/21/2022]
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16
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Hooper DC, Jacoby GA. Topoisomerase Inhibitors: Fluoroquinolone Mechanisms of Action and Resistance. Cold Spring Harb Perspect Med 2016; 6:cshperspect.a025320. [PMID: 27449972 DOI: 10.1101/cshperspect.a025320] [Citation(s) in RCA: 255] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Quinolone antimicrobials are widely used in clinical medicine and are the only current class of agents that directly inhibit bacterial DNA synthesis. Quinolones dually target DNA gyrase and topoisomerase IV binding to specific domains and conformations so as to block DNA strand passage catalysis and stabilize DNA-enzyme complexes that block the DNA replication apparatus and generate double breaks in DNA that underlie their bactericidal activity. Resistance has emerged with clinical use of these agents and is common in some bacterial pathogens. Mechanisms of resistance include mutational alterations in drug target affinity and efflux pump expression and acquisition of resistance-conferring genes. Resistance mutations in one or both of the two drug target enzymes are commonly in a localized domain of the GyrA and ParC subunits of gyrase and topoisomerase IV, respectively, and reduce drug binding to the enzyme-DNA complex. Other resistance mutations occur in regulatory genes that control the expression of native efflux pumps localized in the bacterial membrane(s). These pumps have broad substrate profiles that include other antimicrobials as well as quinolones. Mutations of both types can accumulate with selection pressure and produce highly resistant strains. Resistance genes acquired on plasmids confer low-level resistance that promotes the selection of mutational high-level resistance. Plasmid-encoded resistance is because of Qnr proteins that protect the target enzymes from quinolone action, a mutant aminoglycoside-modifying enzyme that also modifies certain quinolones, and mobile efflux pumps. Plasmids with these mechanisms often encode additional antimicrobial resistances and can transfer multidrug resistance that includes quinolones.
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Affiliation(s)
- David C Hooper
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - George A Jacoby
- Lahey Hospital and Medical Center, Burlington, Massachusetts 01805
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17
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Guo J, Joubran C, Luzietti RA, Basarab GS, Grimm SW, Vishwanathan K. Absorption, distribution, metabolism and elimination of 14C-ETX0914, a novel inhibitor of bacterial type-II topoisomerases in rodents. Xenobiotica 2016; 47:31-49. [PMID: 27122100 DOI: 10.3109/00498254.2016.1156186] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
1. ETX0914 is a novel bacterial topoisomerase inhibitor that has a novel mode-of-inhibition and is in clinical development for the treatment of infections caused by Neisseria gonorrhoeae. 2. The in vitro biotransformation studies of ETX0914 using mouse, rat, dog and human hepatocytes showed moderate intrinsic clearance in mouse and rat and low intrinsic clearance in dog and human. 3. Following intravenous administration of [14C]-ETX0914 in rats, the mean recovery of administered dose in urine, bile and feces was approximately 15%, 55% and 24%, respectively. Unchanged ETX0914 recovered in urine and bile was less than 5% of the dose, indicating that ETX0914 underwent extensive metabolism in rats. Metabolites M1, M2, M4, M6 and M12 detected in both rat and mouse urine samples were not detected in mouse urine when predosed with 1-aminobenzotriazole, indicating that these metabolites were cytochrome P450 mediated products. The major fecal metabolites observed in rats were not formed when ETX0914 was incubated with fresh feces from germ free rats under sterile condition or in incubations with rat intestinal microsome and cytosol, suggesting that most likely ETX0914 was directly excreted into gut lumen where metabolites were formed as intestinal microflora-mediated products. The major sites of metabolism by CYP enzymes were in the morpholine and oxazolidinone rings while it was benzisoxazole reduction with the gut microflora.
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Affiliation(s)
- Jian Guo
- a Department of DMPK AstraZeneca Pharmaceuticals , Waltham , MA , USA.,b Department of DMPK , Celgene Corporation , Bedford , MA , USA
| | - Camil Joubran
- c Department of Chemistry of Infection Innovative Medicine , AstraZeneca Pharmaceuticals , Waltham , MA , USA.,d Analytical Development, Alkermes , Waltham , MA , USA
| | - Ricardo A Luzietti
- a Department of DMPK AstraZeneca Pharmaceuticals , Waltham , MA , USA.,e Full Spectrum Analytics Inc , CA , USA
| | - Gregory S Basarab
- c Department of Chemistry of Infection Innovative Medicine , AstraZeneca Pharmaceuticals , Waltham , MA , USA.,f Department of Chemistry , Drug Discovery and Development Centre, University of Cape Town , Rondebosch , South Africa , and
| | - Scott W Grimm
- c Department of Chemistry of Infection Innovative Medicine , AstraZeneca Pharmaceuticals , Waltham , MA , USA
| | - Karthick Vishwanathan
- a Department of DMPK AstraZeneca Pharmaceuticals , Waltham , MA , USA.,g Early Clinical Development, AstraZeneca Pharmaceuticals , Waltham , MA , USA
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18
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Savage VJ, Charrier C, Salisbury AM, Moyo E, Forward H, Chaffer-Malam N, Metzger R, Huxley A, Kirk R, Uosis-Martin M, Noonan G, Mohmed S, Best SA, Ratcliffe AJ, Stokes NR. Biological profiling of novel tricyclic inhibitors of bacterial DNA gyrase and topoisomerase IV. J Antimicrob Chemother 2016; 71:1905-13. [PMID: 27032669 DOI: 10.1093/jac/dkw061] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 02/17/2016] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES The objective of this study was to characterize the in vitro and in vivo biological properties of a novel series of small-molecule bacterial type IIA topoisomerase inhibitors. METHODS Bacterial susceptibility testing was performed by broth microdilution. Resistance frequencies were determined by plating bacteria onto agar containing test compound and enumerating mutants. Bacteria were passaged using subinhibitory concentrations of antibacterials to generate resistance. Target enzyme inhibition was determined by exposure to antibacterials and DNA; topoisomers were visualized by gel electrophoresis. Oral and intravenous pharmacokinetic profiles were determined in mice. In vivo efficacy was determined using a mouse model of septicaemia and thigh infection with MSSA and MRSA, respectively. RESULTS Representative compounds REDX04139, REDX05604 and REDX05931 demonstrated in vitro potency against a range of Gram-positive and fastidious Gram-negative pathogens. Clinical isolate testing revealed REDX04139 and REDX05931 had MIC90 values of 0.25 and 0.5 mg/L, respectively, for MRSA and MIC90 values of 2 mg/L for streptococci. REDX04139 was bactericidal in vitro against Staphylococcus aureus at 8× MIC over 6 h. Pharmacokinetic profiling of REDX04139 and REDX05604 in mice revealed low clearance and excellent bioavailability (≥71%). REDX04139 provided 100% survival against S. aureus in a mouse septicaemia model, while REDX05604 reduced bacterial load by up to 3.7 log units in the MRSA mouse thigh infection model. CONCLUSIONS Redx Pharma has discovered a novel series of topoisomerase inhibitors that are being further developed for drug-resistant bacteria.
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Affiliation(s)
| | | | | | - Emmanuel Moyo
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | - Henry Forward
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | | | | | - Anthony Huxley
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | - Ralph Kirk
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | | | - Gary Noonan
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | - Sarfraz Mohmed
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | - Stuart A Best
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
| | | | - Neil R Stokes
- Redx Pharma, BioHub, Alderley Park, Cheshire SK10 4TG, UK
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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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20
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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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21
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Bisacchi GS, Hale MR. A "Double-Edged" Scaffold: Antitumor Power within the Antibacterial Quinolone. Curr Med Chem 2016; 23:520-77. [PMID: 26695512 PMCID: PMC4997924 DOI: 10.2174/0929867323666151223095839] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 11/27/2015] [Accepted: 12/22/2015] [Indexed: 12/22/2022]
Abstract
In the late 1980s, reports emerged describing experimental antibacterial quinolones having significant potency against eukaryotic Type II topoisomerases (topo II) and showing cytotoxic activity against tumor cell lines. As a result, several pharmaceutical companies initiated quinolone anticancer programs to explore the potential of this class in comparison to conventional human topo II inhibiting antitumor drugs such as doxorubicin and etoposide. In this review, we present a modern re-evaluation of the anticancer potential of the quinolone class in the context of today's predominantly pathway-based (rather than cytotoxicity-based) oncology drug R&D environment. The quinolone eukaryotic SAR is comprehensively discussed, contrasted with the corresponding prokaryotic data, and merged with recent structural biology information which is now beginning to help explain the basis for that SAR. Quinolone topo II inhibitors appear to be much less susceptible to efflux-mediated resistance, a current limitation of therapy with conventional agents. Recent advances in the biological understanding of human topo II isoforms suggest that significant progress might now be made in overcoming two other treatment-limiting disadvantages of conventional topo II inhibitors, namely cardiotoxicity and drug-induced secondary leukemias. We propose that quinolone class topo II inhibitors could have a useful future therapeutic role due to the continued need for effective topo II drugs in many cancer treatment settings, and due to the recent biological and structural advances which can now provide, for the first time, specific guidance for the design of a new class of inhibitors potentially superior to existing agents.
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Affiliation(s)
- Gregory S Bisacchi
- Syngene International Ltd., Biocon Park, Jigani Link Road, Bangalore 560099, India.
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22
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Protective effect of Qnr on agents other than quinolones that target DNA gyrase. Antimicrob Agents Chemother 2015; 59:6689-95. [PMID: 26239981 DOI: 10.1128/aac.01292-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 07/30/2015] [Indexed: 12/16/2022] Open
Abstract
Qnr is a plasmid-encoded and chromosomally determined protein that protects DNA gyrase and topoisomerase IV from inhibition by quinolones. Despite its prevalence worldwide and existence prior to the discovery of quinolones, its native function is not known. Other synthetic compounds and natural products also target bacterial topoisomerases. A number were studied as molecular probes to gain insight into how Qnr acts. Qnr blocked inhibition by synthetic compounds with somewhat quinolone-like structure that target the GyrA subunit, such as the 2-pyridone ABT-719, the quinazoline-2,4-dione PD 0305970, and the spiropyrimidinetrione pyrazinyl-alkynyl-tetrahydroquinoline (PAT), indicating that Qnr is not strictly quinolone specific, but Qnr did not protect against GyrA-targeting simocyclinone D8 despite evidence that both simocyclinone D8 and Qnr affect DNA binding to gyrase. Qnr did not affect the activity of tricyclic pyrimidoindole or pyrazolopyridones, synthetic inhibitors of the GyrB subunit, or nonsynthetic GyrB inhibitors, such as coumermycin A1, novobiocin, gyramide A, or microcin B17.Thus, in this set of compounds the protective activity of Qnr was confined to those that, like quinolones, trap gyrase on DNA in cleaved complexes.
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Azam MA, Thathan J, Jubie S. Dual targeting DNA gyrase B (GyrB) and topoisomerse IV (ParE) inhibitors: A review. Bioorg Chem 2015; 62:41-63. [PMID: 26232660 DOI: 10.1016/j.bioorg.2015.07.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/19/2015] [Accepted: 07/20/2015] [Indexed: 01/03/2023]
Abstract
GyrB and ParE are type IIA topoisomerases and found in most bacteria. Its function is vital for DNA replication, repair and decatenation. The highly conserved ATP-binding subunits of DNA GyrB and ParE are structurally related and have been recognized as prime candidates for the development of dual-targeting antibacterial agents with broad-spectrum potential. However, no natural product or small molecule inhibitors targeting ATPase catalytic domain of both GyrB and ParE enzymes have succeeded in the clinic. Moreover, no inhibitors of these enzymes with broad-spectrum antibacterial activity against Gram-negative pathogens have been reported. Availability of high resolution crystal structures of GyrB and ParE made it possible for the design of many different classes of inhibitors with dual mechanism of action. Among them benzimidazoles, benzothiazoles, thiazolopyridines, imidiazopyridazoles, pyridines, indazoles, pyrazoles, imidazopyridines, triazolopyridines, pyrrolopyrimidines, pyrimidoindoles as well as related structures are disclosed in literatures. Unfortunately most of these inhibitors are found to be active against Gram-positive pathogens. In the present review we discuss about studies on novel dual targeting ATPase inhibitors.
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Affiliation(s)
- Mohammed Afzal Azam
- Department of Pharmaceutical Chemistry, JSS College of Pharmacy (A Constituent College of JSS University, Mysore), Udhagamandalam 643001, Tamil Nadu, India.
| | - Janarthanan Thathan
- Department of Pharmaceutical Chemistry, JSS College of Pharmacy (A Constituent College of JSS University, Mysore), Udhagamandalam 643001, Tamil Nadu, India
| | - Selvaraj Jubie
- Department of Pharmaceutical Chemistry, JSS College of Pharmacy (A Constituent College of JSS University, Mysore), Udhagamandalam 643001, Tamil Nadu, India
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Chiriac AI, Kloss F, Krämer J, Vuong C, Hertweck C, Sahl HG. Mode of action of closthioamide: the first member of the polythioamide class of bacterial DNA gyrase inhibitors. J Antimicrob Chemother 2015; 70:2576-88. [PMID: 26174721 DOI: 10.1093/jac/dkv161] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Accepted: 05/23/2015] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES The spread of MDR bacteria represents a serious threat to human society and novel antibiotic drugs, preferably from new chemical classes, are urgently needed. Closthioamide was isolated from the strictly anaerobic bacterium Clostridium cellulolyticum and belongs to a new class of natural products, the polythioamides. Here, we investigated the antimicrobial activity and mechanism of action of closthioamide. METHODS For assessing the antimicrobial activity of closthioamide, MIC values and killing kinetics were determined. To identify its target pathway, whole-cell-based assays were used including analysis of macromolecular synthesis and recording the susceptibility profile of a library of clones with down-regulated potential target genes. Subsequently, the inhibitory effect of closthioamide on the activity of isolated target enzymes, e.g. DNA gyrase and topoisomerase IV, was evaluated. RESULTS Closthioamide had broad-spectrum activity against Gram-positive bacteria. Notably, closthioamide was very potent against MRSA and VRE strains. Closthioamide impaired DNA replication and inhibited DNA gyrase activity, in particular the ATPase function of gyrase and of topoisomerase IV, whereas there was little effect on the cleavage-rejoining function. Closthioamide also inhibited the relaxation activity of DNA gyrase, which does not require ATP hydrolysis, and thus may allosterically rather than directly interfere with the ATPase activity of gyrase. Cross-resistance to ciprofloxacin and novobiocin could not be detected in experimental mutants and clinical isolates. CONCLUSIONS Closthioamide, a member of an unprecedented class of antibiotics, is a potent inhibitor of bacterial DNA gyrase; however, its molecular mechanism differs from that of the quinolones and aminocoumarins.
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Affiliation(s)
- Alina Iulia Chiriac
- Pharmaceutical Microbiology Section, Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, Bonn, Germany
| | - Florian Kloss
- Biomolecular Chemistry Department, Leibniz Institute for Natural Product Research and Infection Biology, HKI, Jena, Germany
| | - Jonas Krämer
- Pharmaceutical Microbiology Section, Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, Bonn, Germany
| | - Cuong Vuong
- Department of Bacteriology, AiCuris GmbH & Co. KG, Wuppertal, Germany
| | - Christian Hertweck
- Biomolecular Chemistry Department, Leibniz Institute for Natural Product Research and Infection Biology, HKI, Jena, Germany
| | - Hans-Georg Sahl
- Pharmaceutical Microbiology Section, Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, Bonn, Germany
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25
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Insights into the mechanism of inhibition of novel bacterial topoisomerase inhibitors from characterization of resistant mutants of Staphylococcus aureus. Antimicrob Agents Chemother 2015; 59:5278-87. [PMID: 26077256 DOI: 10.1128/aac.00571-15] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Accepted: 06/09/2015] [Indexed: 11/20/2022] Open
Abstract
The type II topoisomerases DNA gyrase and topoisomerase IV are clinically validated bacterial targets that catalyze the modulation of DNA topology that is vital to DNA replication, repair, and decatenation. Increasing resistance to fluoroquinolones, which trap the topoisomerase-DNA complex, has led to significant efforts in the discovery of novel inhibitors of these targets. AZ6142 is a member of the class of novel bacterial topoisomerase inhibitors (NBTIs) that utilizes a distinct mechanism to trap the protein-DNA complex. AZ6142 has very potent activity against Gram-positive organisms, including Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus pyogenes. In this study, we determined the frequencies of resistance to AZ6142 and other representative NBTI compounds in S. aureus and S. pneumoniae. The frequencies of selection of resistant mutants at 4× the MIC were 1.7 × 10(-8) for S. aureus and <5.5 × 10(-10) for S. pneumoniae. To improve our understanding of the NBTI mechanism of inhibition, the resistant S. aureus mutants were characterized and 20 unique substitutions in the topoisomerase subunits were identified. Many of these substitutions were located outside the NBTI binding pocket and impact the susceptibility of AZ6142, resulting in a 4- to 32-fold elevation in the MIC over the wild-type parent strain. Data on cross-resistance with other NBTIs and fluoroquinolones enabled the differentiation of scaffold-specific changes from compound-specific variations. Our results suggest that AZ6142 inhibits both type II topoisomerases in S. aureus but that DNA gyrase is the primary target. Further, the genotype of the resistant mutants suggests that domain conformations and DNA interactions may uniquely impact NBTIs compared to fluoroquinolones.
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Characterization of the novel DNA gyrase inhibitor AZD0914: low resistance potential and lack of cross-resistance in Neisseria gonorrhoeae. Antimicrob Agents Chemother 2014; 59:1478-86. [PMID: 25534723 DOI: 10.1128/aac.04456-14] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The unmet medical need for novel intervention strategies to treat Neisseria gonorrhoeae infections is significant and increasing, as rapidly emerging resistance in this pathogen is threatening to eliminate the currently available treatment options. AZD0914 is a novel bacterial gyrase inhibitor that possesses potent in vitro activities against isolates with high-level resistance to ciprofloxacin and extended-spectrum cephalosporins, and it is currently in clinical development for the treatment of N. gonorrhoeae infections. The propensity to develop resistance against AZD0914 was examined in N. gonorrhoeae and found to be extremely low, a finding supported by similar studies with Staphylococcus aureus. The genetic characterization of both first-step and second-step mutants that exhibited decreased susceptibilities to AZD0914 identified substitutions in the conserved GyrB TOPRIM domain, confirming DNA gyrase as the primary target of AZD0914 and providing differentiation from fluoroquinolones. The analysis of available bacterial gyrase and topoisomerase IV structures, including those bound to fluoroquinolone and nonfluoroquinolone inhibitors, has allowed the rationalization of the lack of cross-resistance that AZD0914 shares with fluoroquinolones. Microbiological susceptibility data also indicate that the topoisomerase inhibition mechanisms are subtly different between N. gonorrhoeae and other bacterial species. Taken together, these data support the progression of AZD0914 as a novel treatment option for the oral treatment of N. gonorrhoeae infections.
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Optimization of physicochemical properties and safety profile of novel bacterial topoisomerase type II inhibitors (NBTIs) with activity against Pseudomonas aeruginosa. Bioorg Med Chem 2014; 22:5392-409. [DOI: 10.1016/j.bmc.2014.07.040] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/18/2014] [Accepted: 07/26/2014] [Indexed: 01/24/2023]
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Bacillus anthracis GrlAV96A topoisomerase IV, a quinolone resistance mutation that does not affect the water-metal ion bridge. Antimicrob Agents Chemother 2014; 58:7182-7. [PMID: 25246407 DOI: 10.1128/aac.03734-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rise in quinolone resistance is threatening the clinical use of this important class of broad-spectrum antibacterials. Quinolones kill bacteria by increasing the level of DNA strand breaks generated by the type II topoisomerases gyrase and topoisomerase IV. Most commonly, resistance is caused by mutations in the serine and acidic amino acid residues that anchor a water-metal ion bridge that facilitates quinolone-enzyme interactions. Although other mutations in gyrase and topoisomerase IV have been reported in quinolone-resistant strains, little is known regarding their contributions to cellular quinolone resistance. To address this issue, we characterized the effects of the V96A mutation in the A subunit of Bacillus anthracis topoisomerase IV on quinolone activity. The results indicate that this mutation causes an ∼ 3-fold decrease in quinolone potency and reduces the stability of covalent topoisomerase IV-cleaved DNA complexes. However, based on metal ion usage, the V96A mutation does not disrupt the function of the water-metal ion bridge. A similar level of resistance to quinazolinediones (which do not use the bridge) was seen. V96A is the first topoisomerase IV mutation distal to the water-metal ion bridge demonstrated to decrease quinolone activity. It also represents the first A subunit mutation reported to cause resistance to quinazolinediones. This cross-resistance suggests that the V96A change has a global effect on the structure of the drug-binding pocket of topoisomerase IV.
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Guo J, Joubran C, Luzietti RA, Zhou F, Basarab GS, Vishwanathan K. In vitro and in vivo metabolism of 14C-AZ11, a novel inhibitor of bacterial DNA gyrase/type II topoisomerase. Xenobiotica 2014; 45:158-70. [PMID: 25142218 DOI: 10.3109/00498254.2014.952799] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
1. (2R,4S,4aS)-11-Fluoro-2,4-dimethyl-8-((S)-4-methyl-2-oxooxazolidin-3-yl)-2,4,4a,6-tetrahydro-1H,1'H-spiro [isoxazolo[4,5-g][1,4]oxazino[4,3-a]quinoline-5,5'-pyrimidine]-2',4',6'(3'H)-trione (AZ11) is a novel mode-of-inhibition bacterial topoisomerase inhibitor that entered preclinical development for the treatment of Gram-positive bacteria infection. 2. The in vitro biotransformation studies of AZ11 using mouse, rat, dog and human hepatocytes showed low-intrinsic clearance in all species attributed to microsomal metabolism. 3. After a single intravenous administration of [14C]AZ11 in bile duct cannulated rats, the mean percentage of dose recovered in rat urine, bile and feces was approximately 18, 36 and 42%, respectively. Unchanged AZ11 recovered in rat urine and bile was less than 9% of the dose, indicating that AZ11 underwent extensive metabolism in rats. 4. The most abundant in vivo metabolite detected in urine and bile was M1 formed via ring opening on the piperidine and morpholine rings accounting for 20% of the administered dose. The major fecal metabolite was M5, which accounted for approximately 32% of administered dose. M5 was not formed when AZ11 incubated with rat intestinal microsomes and cytosol but was formed when incubated with fresh rat feces, suggesting that unchanged AZ11 was directly excreted into gut lumen where M5 formed as an intestinal microflora-mediated product. This process could have significant impact on bioavailability or exposure of AZ11 in rat.
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Affiliation(s)
- Jian Guo
- Department of DMPK AstraZeneca Pharmaceuticals, Waltham, MA, USA
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Van Horn KS, Burda WN, Fleeman R, Shaw LN, Manetsch R. Antibacterial activity of a series of N2,N4-disubstituted quinazoline-2,4-diamines. J Med Chem 2014; 57:3075-93. [PMID: 24625106 DOI: 10.1021/jm500039e] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of N(2),N(4)-disubstituted quinazoline-2,4-diamines has been synthesized and tested against multidrug resistant Staphylococcus aureus. A structure-activity and structure-property relationship study was conducted to identify new hit compounds. This study led to the identification of N(2),N(4)-disubstituted quinazoline-2,4-diamines with minimum inhibitory concentrations (MICs) in the low micromolar range in addition to favorable physicochemical properties. Testing of biological activity revealed limited potential for resistance to these agents, low toxicity, and highly effective in vivo activity, even with low dosing regimens. Collectively, these characteristics make this compound series a suitable platform for future development of antibacterial agents.
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Affiliation(s)
- Kurt S Van Horn
- Department of Chemistry, University of South Florida , 4202 East Fowler Avenue, CHE 205, Tampa, Florida 33620, 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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Mayer C, Janin YL. Non-quinolone inhibitors of bacterial type IIA topoisomerases: a feat of bioisosterism. Chem Rev 2013; 114:2313-42. [PMID: 24313284 DOI: 10.1021/cr4003984] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Claudine Mayer
- Unité de Microbiologie Structurale, Département de Biologie Structurale et Chimie, Institut Pasteur , 25 rue du Dr. Roux, 75724 Paris Cedex 15, France
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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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35
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Zhou X, Xie X, Liu G. Quinazoline-2,4( $$1H,3H$$ )-diones inhibit the growth of multiple human tumor cell lines. Mol Divers 2013; 17:197-219. [DOI: 10.1007/s11030-012-9421-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 12/27/2012] [Indexed: 12/01/2022]
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36
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Los R, Wesołowska-Trojanowska M, Malm A, Karpińska MM, Matysiak J, Niewiadomy A, Głaszcz U. A new approach to the synthesis of 2-aryl-substituted benzimidazoles, quinazolines, and other related compounds and their antibacterial activity. HETEROATOM CHEMISTRY 2012. [DOI: 10.1002/hc.21012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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37
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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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38
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Noreddin AM, Elkhatib WF, Cunnion KM, Zhanel GG. Cumulative clinical experience from over a decade of use of levofloxacin in community-acquired pneumonia: critical appraisal and role in therapy. DRUG HEALTHCARE AND PATIENT SAFETY 2011; 3:59-68. [PMID: 22046107 PMCID: PMC3202762 DOI: 10.2147/dhps.s15599] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Indexed: 11/23/2022]
Abstract
Levofloxacin is the synthetic L-isomer of the racemic fluoroquinolone, ofloxacin. It interferes with critical processes in the bacterial cell such as DNA replication, transcription, repair, and recombination by inhibiting bacterial topoisomerases. Levofloxacin has broad spectrum activity against several causative bacterial pathogens of community-acquired pneumonia (CAP). Oral levofloxacin is rapidly absorbed and is bioequivalent to the intravenous formulation such that patients can be conveniently transitioned between these formulations when moving from the inpatient to the outpatient setting. Furthermore, levofloxacin demonstrates excellent safety, and has good tissue penetration maintaining adequate concentrations at the site of infection. The efficacy and tolerability of levofloxacin 500 mg once daily for 10 days in patients with CAP are well established. Furthermore, a high-dose (750 mg) and short-course (5 days) of once-daily levofloxacin has been approved for use in the US in the treatment of CAP, acute bacterial sinusitis, acute pyelonephritis, and complicated urinary tract infections. The high-dose, short-course levofloxacin regimen maximizes its concentration-dependent antibacterial activity, decreases the potential for drug resistance, and has better patient compliance.
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Affiliation(s)
- Ayman M Noreddin
- Department of Pharmacy Practice, Hampton University, Hampton, VA, USA
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López-Rojas R, Sánchez-Céspedes J, Docobo-Pérez F, Domínguez-Herrera J, Vila J, Pachón J. Pre-clinical studies of a new quinolone (UB-8902) against Acinetobacter baumannii resistant to ciprofloxacin. Int J Antimicrob Agents 2011; 38:355-9. [DOI: 10.1016/j.ijantimicag.2011.06.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 06/02/2011] [Accepted: 06/07/2011] [Indexed: 10/17/2022]
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40
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Collin F, Karkare S, Maxwell A. Exploiting bacterial DNA gyrase as a drug target: current state and perspectives. Appl Microbiol Biotechnol 2011; 92:479-97. [PMID: 21904817 PMCID: PMC3189412 DOI: 10.1007/s00253-011-3557-z] [Citation(s) in RCA: 364] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 08/08/2011] [Accepted: 08/18/2011] [Indexed: 12/17/2022]
Abstract
DNA gyrase is a type II topoisomerase that can introduce negative supercoils into DNA at the expense of ATP hydrolysis. It is essential in all bacteria but absent from higher eukaryotes, making it an attractive target for antibacterials. The fluoroquinolones are examples of very successful gyrase-targeted drugs, but the rise in bacterial resistance to these agents means that we not only need to seek new compounds, but also new modes of inhibition of this enzyme. We review known gyrase-specific drugs and toxins and assess the prospects for developing new antibacterials targeted to this enzyme.
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Affiliation(s)
- Frédéric Collin
- Department Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
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41
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Bush K, Pucci MJ. New antimicrobial agents on the horizon. Biochem Pharmacol 2011; 82:1528-39. [PMID: 21798250 DOI: 10.1016/j.bcp.2011.07.077] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 07/08/2011] [Accepted: 07/11/2011] [Indexed: 12/18/2022]
Abstract
Antibiotic resistance issues necessitate the continued discovery and development of new antibacterial agents. Efforts are ongoing in two approaches to find new compounds that are effective against antibiotic-resistant pathogens. These efforts involve modification of existing classes including fluoroquinolones, tetracyclines, aminoglycosides, and β-lactams and identification of inhibitors against previously unexploited antibacterial targets. Examples of both approaches are described here with emphasis on compounds in late pre-clinical or clinical stages of development.
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Affiliation(s)
- Karen Bush
- Department of Biology, Jordan Hall, 1001 E. Third Street, Indiana University, Bloomington, IN 47405, United States.
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42
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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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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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Boyapati S, Kulandaivelu U, Sangu S, Vanga MR. Synthesis, antimicrobial evaluation, and docking studies of novel 4-substituted quinazoline derivatives as DNA-gyrase inhibitors. Arch Pharm (Weinheim) 2011; 343:570-6. [PMID: 20941729 DOI: 10.1002/ardp.201000065] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Quinazoline derivatives are reported to have anti-inflammatory, analgesic, antibacterial, and anticancer activities. The incorporation of "OCH₂CONH₂" (oxymethylcarbamide) at 4th position of the quinazoline ring was found to influence the biological activities of the molecules. With this rationale, some new oxadiazolyl methyloxy quinazolines, pyrazolyl acetoxy methyl quinazolines, triazolylmethyloxy quinazolines were synthesized from anthranilic acid through quinazolyl oxyacetylhydrazide intermediates. All the compounds were characterized by IR, ¹H-NMR, EI-MS, and C, H, N analyses and evaluated for their antimicrobial activity. Docking studies on the DNA-gyrase enzyme (1KZN) show their role in the antimicrobial activity of the molecules and explain the higher potency of compounds 6a, 6b, 8a, 8b based on ReRanking scores and binding poses of the molecules.
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Affiliation(s)
- Shireesha Boyapati
- Medicinal Chemistry Research Division, Vaagdevi College of Pharmacy, Hanamkonda, Warangal, A.P, India.
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Abstract
The discovery of novel small-molecule antibacterial drugs has been stalled for many years. The purpose of this review is to underscore and illustrate those scientific problems unique to the discovery and optimization of novel antibacterial agents that have adversely affected the output of the effort. The major challenges fall into two areas: (i) proper target selection, particularly the necessity of pursuing molecular targets that are not prone to rapid resistance development, and (ii) improvement of chemical libraries to overcome limitations of diversity, especially that which is necessary to overcome barriers to bacterial entry and proclivity to be effluxed, especially in Gram-negative organisms. Failure to address these problems has led to a great deal of misdirected effort.
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Affiliation(s)
- Lynn L Silver
- LL Silver Consulting, LLC, 955 S. Springfield Ave., Unit C403, Springfield, NJ 07081, USA.
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Noreddin AM, Elkhatib WF. Levofloxacin in the treatment of community-acquired pneumonia. Expert Rev Anti Infect Ther 2010; 8:505-14. [PMID: 20455679 DOI: 10.1586/eri.10.35] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Levofloxacin is a fluoroquinolone that has a broad spectrum of activity against several causative bacterial pathogens of community-acquired pneumonia (CAP). The efficacy and tolerability of levofloxacin 500 mg once daily for 10 days in patients with CAP are well established. Furthermore, a high-dose (750 mg), short-course (5 days) of once-daily levofloxacin has been approved for use in the USA in the treatment of CAP, acute bacterial sinusitis, acute pyelonephritis and complicated urinary tract infections. Levofloxacin can be used as a monotherapy in patients with CAP, however, levofloxacin combination therapy with anti-pseudomonal beta-lactam (or aminoglycoside) should be considered if Pseudomonas aeruginosa is the causative pathogen of the respiratory infection. The high-dose, short-course levofloxacin regimen maximizes its concentration-dependent antibacterial activity, decreases the potential for drug resistance and has better patient compliance. Oral levofloxacin is rapidly absorbed and is bioequivalent to the intravenous formulation and the patients can switch between these formulations, which results in more options with respect to the therapeutic regimens. Furthermore, levofloxacin is generally well tolerated, has good tissue penetration and adequate concentrations can be maintained at the site of infections.
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Affiliation(s)
- Ayman M Noreddin
- Department of Pharmacy Practice, School of Pharmacy, Hampton University, Hampton, VA 23668, USA.
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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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Laponogov I, Pan XS, Veselkov DA, McAuley KE, Fisher LM, Sanderson MR. Structural basis of gate-DNA breakage and resealing by type II topoisomerases. PLoS One 2010; 5:e11338. [PMID: 20596531 PMCID: PMC2893164 DOI: 10.1371/journal.pone.0011338] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 06/07/2010] [Indexed: 11/23/2022] Open
Abstract
Type II DNA topoisomerases are ubiquitous enzymes with essential functions in DNA replication, recombination and transcription. They change DNA topology by forming a transient covalent cleavage complex with a gate-DNA duplex that allows transport of a second duplex though the gate. Despite its biological importance and targeting by anticancer and antibacterial drugs, cleavage complex formation and reversal is not understood for any type II enzyme. To address the mechanism, we have used X-ray crystallography to study sequential states in the formation and reversal of a DNA cleavage complex by topoisomerase IV from Streptococcus pneumoniae, the bacterial type II enzyme involved in chromosome segregation. A high resolution structure of the complex captured by a novel antibacterial dione reveals two drug molecules intercalated at a cleaved B-form DNA gate and anchored by drug-specific protein contacts. Dione release generated drug-free cleaved and resealed DNA complexes in which the DNA gate instead adopts an unusual A/B-form helical conformation with a Mg2+ ion repositioned to coordinate each scissile phosphodiester group and promote reversible cleavage by active-site tyrosines. These structures, the first for putative reaction intermediates of a type II topoisomerase, suggest how a type II enzyme reseals DNA during its normal reaction cycle and illuminate aspects of drug arrest important for the development of new topoisomerase-targeting therapeutics.
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Affiliation(s)
- Ivan Laponogov
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
- Division of Basic Medical Sciences, St George's University of London, London, United Kingdom
| | - Xiao-Su Pan
- Division of Basic Medical Sciences, St George's University of London, London, United Kingdom
| | - Dennis A. Veselkov
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
| | | | - L. Mark Fisher
- Division of Basic Medical Sciences, St George's University of London, London, United Kingdom
- * E-mail: (LMF); (MRS)
| | - Mark R. Sanderson
- Randall Division of Cell and Molecular Biophysics, King's College London, London, United Kingdom
- * E-mail: (LMF); (MRS)
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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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Ananthan S, Faaleolea ER, Goldman RC, Hobrath JV, Kwong CD, Laughon BE, Maddry JA, Mehta A, Rasmussen L, Reynolds RC, Secrist JA, Shindo N, Showe DN, Sosa MI, Suling WJ, White EL. High-throughput screening for inhibitors of Mycobacterium tuberculosis H37Rv. Tuberculosis (Edinb) 2009; 89:334-53. [PMID: 19758845 DOI: 10.1016/j.tube.2009.05.008] [Citation(s) in RCA: 221] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 05/20/2009] [Accepted: 05/27/2009] [Indexed: 10/20/2022]
Abstract
There is an urgent need for the discovery and development of new antitubercular agents that target new biochemical pathways and treat drug resistant forms of the disease. One approach to addressing this need is through high-throughput screening of medicinally relevant libraries against the whole bacterium in order to discover a variety of new, active scaffolds that will stimulate new biological research and drug discovery. Through the Tuberculosis Antimicrobial Acquisition and Coordinating Facility (www.taacf.org), a large, medicinally relevant chemical library was screened against M. tuberculosis strain H37Rv. The screening methods and a medicinal chemistry analysis of the results are reported herein.
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Affiliation(s)
- Subramaniam Ananthan
- Southern Research Institute, 2000 Ninth Avenue South, Birmingham, AL 35205, USA.
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