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Sullivan JR, Lupien A, Kalthoff E, Hamela C, Taylor L, Munro KA, Schmeing TM, Kremer L, Behr MA. Efficacy of epetraborole against Mycobacterium abscessus is increased with norvaline. PLoS Pathog 2021; 17:e1009965. [PMID: 34637487 PMCID: PMC8535176 DOI: 10.1371/journal.ppat.1009965] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 10/22/2021] [Accepted: 09/23/2021] [Indexed: 12/16/2022] Open
Abstract
Mycobacterium abscessus is the most common rapidly growing non-tuberculous mycobacteria to cause pulmonary disease in patients with impaired lung function such as cystic fibrosis. M. abscessus displays high intrinsic resistance to common antibiotics and inducible resistance to macrolides like clarithromycin. As such, M. abscessus is clinically resistant to the entire regimen of front-line M. tuberculosis drugs, and treatment with antibiotics that do inhibit M. abscessus in the lab results in cure rates of 50% or less. Here, we identified epetraborole (EPT) from the MMV pandemic response box as an inhibitor against the essential protein leucyl-tRNA synthetase (LeuRS) in M. abscessus. EPT protected zebrafish from lethal M. abscessus infection and did not induce self-resistance nor against clarithromycin. Contrary to most antimycobacterials, the whole-cell activity of EPT was greater against M. abscessus than M. tuberculosis, but crystallographic and equilibrium binding data showed that EPT binds LeuRSMabs and LeuRSMtb with similar residues and dissociation constants. Since EPT-resistant M. abscessus mutants lost LeuRS editing activity, these mutants became susceptible to misaminoacylation with leucine mimics like the non-proteinogenic amino acid norvaline. Proteomic analysis revealed that when M. abscessus LeuRS mutants were fed norvaline, leucine residues in proteins were replaced by norvaline, inducing the unfolded protein response with temporal changes in expression of GroEL chaperonins and Clp proteases. This supports our in vitro data that supplementation of media with norvaline reduced the emergence of EPT mutants in both M. abscessus and M. tuberculosis. Furthermore, the combination of EPT and norvaline had improved in vivo efficacy compared to EPT in a murine model of M. abscessus infection. Our results emphasize the effectiveness of EPT against the clinically relevant cystic fibrosis pathogen M. abscessus, and these findings also suggest norvaline adjunct therapy with EPT could be beneficial for M. abscessus and other mycobacterial infections like tuberculosis. Current antimycobacterial drugs are inadequate to handle the increasing number of non-tuberculous mycobacteria infections that eclipse tuberculosis infections in many developed countries. Of particular importance for cystic fibrosis patients, Mycobacterium abscessus is notoriously difficult to treat where patients spend extended time on antibiotics with cure rates comparable to extreme drug resistant M. tuberculosis. Here, we identified epetraborole (EPT) with in vitro and in vivo activities against M. abscessus. We showed that EPT targets the editing domain of the leucyl-tRNA synthetase (LeuRS) and that escape mutants lost LeuRS editing activity, making these mutants susceptible to misaminoacylation with leucine mimics. Most importantly, combination therapy of EPT and norvaline limited the rate of EPT resistance in both M. abscessus and M. tuberculosis, and this was the first study to demonstrate improved in vivo efficacy of EPT and norvaline compared to EPT in a murine model of M. abscessus pulmonary infection. The demonstration of norvaline adjunct therapy with EPT for M. abscessus infections is promising for cystic fibrosis patients and could translate to other mycobacterial infections, such as tuberculosis.
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Affiliation(s)
- Jaryd R. Sullivan
- Department of Microbiology & Immunology, McGill University, Montréal, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Canada
- McGill International TB Centre, Montréal, Canada
| | - Andréanne Lupien
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Canada
- McGill International TB Centre, Montréal, Canada
| | - Elias Kalthoff
- Department of Biochemistry, McGill University, Montréal, Canada
- Centre de Recherche en Biologie Structural, McGill University, Montréal, Canada
| | - Claire Hamela
- Centre National de la Recherche Scientifique UMR 9004, Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, Montpellier, France
| | - Lorne Taylor
- Clinical Proteomics Platform, Research Institute of the McGill University Health Centre, Montréal, Canada
| | - Kim A. Munro
- Department of Biochemistry, McGill University, Montréal, Canada
- Centre de Recherche en Biologie Structural, McGill University, Montréal, Canada
| | - T. Martin Schmeing
- Department of Biochemistry, McGill University, Montréal, Canada
- Centre de Recherche en Biologie Structural, McGill University, Montréal, Canada
| | - Laurent Kremer
- Centre National de la Recherche Scientifique UMR 9004, Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, Montpellier, France
- INSERM, IRIM, Montpellier, France
| | - Marcel A. Behr
- Department of Microbiology & Immunology, McGill University, Montréal, Canada
- Infectious Diseases and Immunity in Global Health Program, Research Institute of the McGill University Health Centre, Montréal, Canada
- McGill International TB Centre, Montréal, Canada
- Department of Medicine, McGill University Health Centre, Montréal, Canada
- * E-mail:
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2
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Yan C, Zhang J, Wu P, Gan Y, Zhang G. An EDTA-resistant pyrazinamidase from non-pathogen Pseudonocardia carboxydivorans. Biotechnol Lett 2020; 42:1707-1718. [PMID: 32323078 DOI: 10.1007/s10529-020-02890-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 04/14/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVES To characterize a pyrazinamidase from non-pathogen Pseudonocardia carboxydivorans. RESULTS A pyrazinamidase gene pncA encoding a 23-kDa protein PncA-Pse from P. carboxydivorans was over-expressed in Escherichia coli and characterized. This PncA-Pse can convert both pyrazinamide and nicotinamide efficiently with the optimal pH and temperature of pH 8.5 and 45 °C, respectively. Although ferrous iron and manganese were detected in PncA-Pse, the enzymatic activity is not affected by EDTA with the final concentration of 10 mM. Moreover, the enzymatic activity was not significantly affected with the addition of several metal ions, respectively. Based on the structure modeling, the 61st histidine which is associated with the metal binding, was mutated into alanine to get mutant H61A. No activity, iron and manganese were detected for H61A, which implies that PncA-Pse is a metal enzyme with resistance of the metal ion chelator EDTA, which is different from the previous reports. CONCLUSION This is the first characterized pyrazinamidase from the genus Pseudonocardia, a non-pathogen.
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Affiliation(s)
- Chuang Yan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Jingxuan Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Pan Wu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China
| | - Yong Gan
- Zhejiang Anglikang Pharmaceutical Co., Ltd. Shengzhou, Shaoxing, 312400, Zhejiang, China
| | - Guimin Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, 430062, Hubei, China.
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3
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Xu J, Chen Y, Mou X, Huang Y, Ma S, Zhang L, Zhang Y, Long Q, Ali MK, Xie J. Mycobacterium smegmatis msmeg_3314 is involved in pyrazinamide and fluoroquinolones susceptibility via NAD +/NADH dysregulation. Future Microbiol 2020; 15:413-426. [PMID: 32250176 DOI: 10.2217/fmb-2019-0071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To identify and characterize new mycobacterium pyrazinamide (PZA) resistance genes in addition to pncA, rpsA and panD. Materials & methods: To screen a Tn7 M. smegmatis mc2155 transposon library using 50 μM PZA and a PZA hypersensitive mutant (M492) was obtained. MIC was further used to confirm the hypersensitivity of M492 mutant by culturing the mutant in Middlebrook 7H9 liquid medium at 37°C. Results: msmeg_3314 is the gene underlying the hypersensitive phenotype of mutant M492. The observed resistance to PZA and fluoroquinolones involved the alteration of Mycobacterium cell wall permeability and the dissipation of the proton motive force. NAD+/NADH dysregulation and attenuated glyoxylate shunt might underlie the declined scavenging capacity of reactive oxygen species in the msmeg_3314-deficient mutants. Conclusion: msmeg_ 3314 is a novel gene involved in pyrazinamide resistance and might be a new candidate for drugs target.
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Affiliation(s)
- Junqi Xu
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Yu Chen
- Shenyang Tenth People's Hospital (Shenyang Chest Hospital), Dadong District, Shenyang City, Liaoning 110044, China
| | - Xi Mou
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Yu Huang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Shuang Ma
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Liyuan Zhang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Yuan Zhang
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Quanxin Long
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China.,The Second Affiliated Hospital & the Key Laboratory of Molecular Biology of Infectious Diseases of The Ministry of Education, Chongqing Medical University, Yuzhong District, Chongqing 400016, China
| | - Md Kaisar Ali
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment & Bio-Resource of The Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing 400715, China
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4
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Antibiotic resistance genes in the Actinobacteria phylum. Eur J Clin Microbiol Infect Dis 2019; 38:1599-1624. [PMID: 31250336 DOI: 10.1007/s10096-019-03580-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/01/2019] [Indexed: 02/07/2023]
Abstract
The Actinobacteria phylum is one of the oldest bacterial phyla that have a significant role in medicine and biotechnology. There are a lot of genera in this phylum that are causing various types of infections in humans, animals, and plants. As well as antimicrobial agents that are used in medicine for infections treatment or prevention of infections, they have been discovered of various genera in this phylum. To date, resistance to antibiotics is rising in different regions of the world and this is a global health threat. The main purpose of this review is the molecular evolution of antibiotic resistance in the Actinobacteria phylum.
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Wu ML, Aziz DB, Dartois V, Dick T. NTM drug discovery: status, gaps and the way forward. Drug Discov Today 2018; 23:1502-1519. [PMID: 29635026 DOI: 10.1016/j.drudis.2018.04.001] [Citation(s) in RCA: 168] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/09/2018] [Accepted: 04/03/2018] [Indexed: 12/22/2022]
Abstract
Incidence of pulmonary diseases caused by non-tuberculous mycobacteria (NTM), relatives of Mycobacterium tuberculosis, is increasing at an alarming rate, surpassing tuberculosis in many countries. Current chemotherapies require long treatment times and the clinical outcomes are often disappointing. There is an urgent medical need to discover and develop new, more-efficacious anti-NTM drugs. In this review, we summarize the current status of NTM drug development, and highlight knowledge gaps and scientific obstacles in NTM drug discovery. We propose strategies to reduce biological uncertainties and to begin to populate a NTM drug pipeline with attractive leads and drug candidates.
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Affiliation(s)
- Mu-Lu Wu
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, 117599, Singapore
| | - Dinah B Aziz
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 14 Medical Drive, 117599, Singapore
| | - Véronique Dartois
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, 225 Warren Street, Newark, NJ 07103, USA
| | - Thomas Dick
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, 225 Warren Street, Newark, NJ 07103, USA.
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6
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Zhang Z, Ordonez AA, Smith-Jones P, Wang H, Gogarty KR, Daryaee F, Bambarger LE, Chang YS, Jain SK, Tonge PJ. The biodistribution of 5-[18F]fluoropyrazinamide in Mycobacterium tuberculosis-infected mice determined by positron emission tomography. PLoS One 2017; 12:e0170871. [PMID: 28151985 PMCID: PMC5289470 DOI: 10.1371/journal.pone.0170871] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 01/11/2017] [Indexed: 02/03/2023] Open
Abstract
5-[18F]F-pyrazinamide (5-[18F]F-PZA), a radiotracer analog of the first-line tuberculosis drug pyrazinamide (PZA), was employed to determine the biodistribution of PZA using PET imaging and ex vivo analysis. 5-[18F]F-PZA was synthesized in 60 min using a halide exchange reaction. The overall decay-corrected yield of the reaction was 25% and average specific activity was 2.6 × 106 kBq (70 mCi)/μmol. The biodistribution of 5-[18F]F-PZA was examined in a pulmonary Mycobacterium tuberculosis mouse model, where rapid distribution of the tracer to the lung, heart, liver, kidney, muscle, and brain was observed. The concentration of 5-[18F]F-PZA was not significantly different between infected and uninfected lung tissue. Biochemical and microbiological studies revealed substantial differences between 5-F-PZA and PZA. 5-F-PZA was not a substrate for pyrazinamidase, the bacterial enzyme that activates PZA, and the minimum inhibitory concentration for 5-F-PZA against M. tuberculosis was more than 100-fold higher than that for PZA.
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Affiliation(s)
- Zhuo Zhang
- Institute for Chemical Biology & Drug Discovery, Department of Chemistry and Department of Radiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Alvaro A. Ordonez
- Center for Infection and Inflammation Imaging Research, Center for Tuberculosis Research and Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Peter Smith-Jones
- The Facility for Experimental Radiopharmaceutical Manufacturing, Department of Psychiatry, Stony Brook University, Stony Brook, New York, United States of America
| | - Hui Wang
- Institute for Chemical Biology & Drug Discovery, Department of Chemistry and Department of Radiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Kayla R. Gogarty
- Institute for Chemical Biology & Drug Discovery, Department of Chemistry and Department of Radiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Fereidoon Daryaee
- Institute for Chemical Biology & Drug Discovery, Department of Chemistry and Department of Radiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Lauren E. Bambarger
- Center for Infection and Inflammation Imaging Research, Center for Tuberculosis Research and Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Yong S. Chang
- Center for Infection and Inflammation Imaging Research, Center for Tuberculosis Research and Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Sanjay K. Jain
- Center for Infection and Inflammation Imaging Research, Center for Tuberculosis Research and Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (SKJ); (PJT)
| | - Peter J. Tonge
- Institute for Chemical Biology & Drug Discovery, Department of Chemistry and Department of Radiology, Stony Brook University, Stony Brook, New York, United States of America
- * E-mail: (SKJ); (PJT)
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7
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Sayahi H, Pugliese KM, Zimhony O, Jacobs WR, Shekhtman A, Welch JT. Analogs of the antituberculous agent pyrazinamide are competitive inhibitors of NADPH binding to M. tuberculosis fatty acid synthase I. Chem Biodivers 2013; 9:2582-96. [PMID: 23161636 DOI: 10.1002/cbdv.201200291] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Indexed: 11/10/2022]
Abstract
Analogs of pyrazinamide (=pyrazine-2-carboxamide; PZA), an essential component of short-course antituberculous chemotherapy, such as 5-chloropyrazinamide (5-Cl-PZA) act as competitive inhibitors of NADPH binding to purified mycobacterial fatty acid synthase I (FAS I) as shown by Saturation Transfer Difference (STD) NMR studies. In addition, pyrazinoic acid esters (POE) and 5-Cl-POE reversibly bind to FAS I with the relatively greater affinity of longer-chain esters for FAS I, clear from the STD amplification factors. The competitive binding of PZA and 5-Cl-PZA clearly illustrates that both agents bind FAS. In contrast to PZA, at low NADPH concentrations 5-Cl-PZA is a cooperative inhibitor of NADPH binding.
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Affiliation(s)
- Halimah Sayahi
- Department of Chemistry, University at Albany, SUNY, 1400 Washington Ave, Albany, NY 12222, USA
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8
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Evaluation of methods for testing the susceptibility of clinical Mycobacterium tuberculosis isolates to pyrazinamide. J Clin Microbiol 2013; 51:1374-80. [PMID: 23390285 DOI: 10.1128/jcm.03197-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide (PZA) is a first-line antituberculosis (anti-TB) drug capable of killing nonreplicating, persistent Mycobacterium tuberculosis. However, reliable testing of the susceptibility of M. tuberculosis to PZA is challenging. Using 432 clinical M. tuberculosis isolates, we compared the performances of five methods for the determination of M. tuberculosis susceptibility to PZA: the MGIT 960 system, the molecular drug susceptibility test (mDST), the pyrazinamidase (PZase) activity assay, the resazurin microtiter assay (REMA), and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction test. The sensitivities of the MGIT 960 system, the PZase activity assay, the mDST, the REMA, and the MTT assay were 98.8%, 88.8%, 90.5%, 98.8%, and 98.2%, respectively. The sensitivities of the PZase activity assay and the mDST were lower than those of the other three methods (P < 0.05). The specificities of the MGIT 960 system, the PZase activity assay, the mDST, the REMA and the MTT assays were 99.2%, 98.9%, 90.9%, 98.5%, and 100%, respectively. The specificity of the mDST was lower than those of the other four methods (P < 0.05). In conclusion, the MGIT 960 system, the MTT assay, and the REMA are superior to the PZase activity assay and the mDST in determining the susceptibility of M. tuberculosis to PZA. The MTT assay and the REMA might serve as alternative methods for clinical laboratories without access to the MGIT 960 system. For rapid testing in well-equipped laboratories, the mDST might be the best choice, particularly for small quantities of M. tuberculosis. The PZase activity assay has no obvious advantage in the assessment of M. tuberculosis susceptibility to PZA, as it is less accurate and requires larger quantities of bacteria.
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Gene sequencing for routine verification of pyrazinamide resistance in Mycobacterium tuberculosis: a role for pncA but not rpsA. J Clin Microbiol 2012; 50:3726-8. [PMID: 22895038 DOI: 10.1128/jcm.00620-12] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide (PZA) is an important component of first-line therapy for the treatment of tuberculosis. Here, we evaluate targeted gene sequencing as a supplement to phenotypic PZA susceptibility testing of Mycobacterium tuberculosis. Routine sequencing of pncA, but not rpsA, is effective for verification of PZA susceptibility results.
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10
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Antibacterial activities of naturally occurring compounds against Mycobacterium avium subsp. paratuberculosis. Appl Environ Microbiol 2008; 74:5986-90. [PMID: 18676709 DOI: 10.1128/aem.00981-08] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The antibacterial activities of 18 naturally occurring compounds (including essential oils and some of their isolated constituents, apple and green tea polyphenols, and other plant extracts) against three strains of Mycobacterium avium subsp. paratuberculosis (a bovine isolate [NCTC 8578], a raw-milk isolate [806R], and a human isolate [ATCC 43015]) were evaluated using a macrobroth susceptibility testing method. M. avium subsp. paratuberculosis was grown in 4 ml Middlebrook 7H9 broth containing 10% oleic acid-albumin-dextrose-catalase, 0.05% Tween 80 (or 0.2% glycerol), and 2 microg/ml mycobactin J supplemented with five concentrations of each test compound. The changes in the optical densities of the cultures at 600 nm as a measure of CFU were recorded at intervals over an incubation period of 42 days at 37 degrees C. Six of the compounds were found to inhibit the growth of M. avium subsp. paratuberculosis. The most effective compound was trans-cinnamaldehyde, with a MIC of 25.9 microg/ml, followed by cinnamon oil (26.2 microg/ml), oregano oil (68.2 microg/ml), carvacrol (72.2 microg/ml), 2,5-dihydroxybenzaldehyde (74 microg/ml), and 2-hydroxy-5-methoxybenzaldehyde (90.4 microg/ml). With the exception of carvacrol, a phenolic compound, three of the four most active compounds are aldehydes, suggesting that the structure of the phenolic group or the aldehyde group may be important to the antibacterial activity. No difference in compound activity was observed between the three M. avium subsp. paratuberculosis strains studied. Possible mechanisms of the antimicrobial effects are discussed.
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11
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Ngo SC, Zimhony O, Chung WJ, Sayahi H, Jacobs WR, Welch JT. Inhibition of isolated Mycobacterium tuberculosis fatty acid synthase I by pyrazinamide analogs. Antimicrob Agents Chemother 2007; 51:2430-5. [PMID: 17485499 PMCID: PMC1913273 DOI: 10.1128/aac.01458-06] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An analog of pyrazinamide (PZA), 5-chloropyrazinamide (5-Cl-PZA), has previously been shown to inhibit mycobacterial fatty acid synthase I (FASI). FASI has been purified from a recombinant strain of M. smegmatis (M. smegmatis Deltafas1 attB::M. tuberculosis fas1). Following purification, FASI activity and inhibition were assessed spectrophotometrically by monitoring NADPH oxidation. The observed inhibition was both concentration and structure dependent, being affected by both substitution at the 5 position of the pyrazine nucleus and the nature of the ester or N-alkyl group. Under the conditions studied, both 5-Cl-PZA and PZA exhibited concentration and substrate dependence consistent with competitive inhibition of FASI with K(i)s of 55 to 59 microM and 2,567 to 2,627 microM, respectively. The results were validated utilizing a radiolabeled fatty acid synthesis assay. This assay showed that FASI was inhibited by PZA and pyrazinoic acid as well as by a series of PZA analogs.
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Affiliation(s)
- Silvana C Ngo
- Department of Chemistry, University at Albany-SUNY, Albany, NY 12222, USA
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12
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Bamaga M, Wright DJM, Zhang H. Selection of in vitro mutants of pyrazinamide-resistant Mycobacterium tuberculosis. Int J Antimicrob Agents 2002; 20:275-81. [PMID: 12385684 DOI: 10.1016/s0924-8579(02)00182-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Mutations within the pncA gene coding for pyrazinamidase of Mycobacterium tuberculosis can cause pyrazinamide (PZA) resistance. The effect of drug concentrations on PZA resistance in a clinical isolate of M. tuberculosis was studied in vitro. Serial passage at gradually increased concentrations of PZA from 200 to 500 microg/ml was performed using BACTEC radiometric method. Thirteen in vitro-selected variant strains were assembled and sequence analysis showed that 12 of the 13 variants had a novel single point mutation within the pncA gene by deletion at nucleotide 381 (G), codon 127. This lead to a frameshift that affected the function of the pyrazinamidase resulting in PZA resistance regardless of different PZA concentrations used. One variant had a silent mutation at nucleotide 6 (G-->A) and remains PZA sensitive. We conclude that the mutation location found is an important position for full resistance, at least in this strain. The lack of further mutations even after exposure to higher PZA concentrations implies a critical value for development of resistance-a level exceeded in tissues in clinical treatment regimes.
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Affiliation(s)
- M Bamaga
- Department of Infectious Diseases and Microbiology, Division of Investigative Science, Imperial College School of Medicine, SAF Building, 1st Floor, Exhibition Road, SW7 2AZ, London, UK
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13
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Boshoff HI, Mizrahi V, Barry CE. Effects of pyrazinamide on fatty acid synthesis by whole mycobacterial cells and purified fatty acid synthase I. J Bacteriol 2002; 184:2167-72. [PMID: 11914348 PMCID: PMC134955 DOI: 10.1128/jb.184.8.2167-2172.2002] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effects of low extracellular pH and intracellular accumulation of weak organic acids were compared with respect to fatty acid synthesis by whole cells of Mycobacterium tuberculosis and Mycobacterium smegmatis. The profile of fatty acids synthesized during exposure to benzoic, nicotinic, or pyrazinoic acids, as well as that observed during intracellular hydrolysis of the corresponding amides, was not a direct consequence of modulation of fatty acid synthesis by these compounds but reflected the response to inorganic acid stress. Analysis of fatty acid synthesis in crude mycobacterial cell extracts demonstrated that pyrazinoic acid failed to directly modulate the fatty acid synthase activity catalyzed by fatty acid synthase I (FAS-I). However, fatty acid synthesis was irreversibly inhibited by 5-chloro-pyrazinamide in a time-dependent fashion. Moreover, we demonstrate that pyrazinoic acid does not inhibit purified mycobacterial FAS-I, suggesting that this enzyme is not the immediate target of pyrazinamide.
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Affiliation(s)
- Helena I Boshoff
- Tuberculosis Research Section, National Institute of Allergy and Infectious Diseases, Rockville, Maryland 20852, USA
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Boshoff HI, Mizrahi V. Expression of Mycobacterium smegmatis pyrazinamidase in Mycobacterium tuberculosis confers hypersensitivity to pyrazinamide and related amides. J Bacteriol 2000; 182:5479-85. [PMID: 10986252 PMCID: PMC110992 DOI: 10.1128/jb.182.19.5479-5485.2000] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2000] [Accepted: 07/05/2000] [Indexed: 11/20/2022] Open
Abstract
A pyrazinamidase (PZase)-deficient pncA mutant of Mycobacterium tuberculosis, constructed by allelic exchange, was used to investigate the effects of heterologous amidase gene expression on the susceptibility of this organism to pyrazinamide (PZA) and related amides. The mutant was highly resistant to PZA (MIC, >2,000 microg/ml), in accordance with the well-established role of pncA in the PZA susceptibility of M. tuberculosis (A. Scorpio and Y. Zhang, Nat. Med. 2:662-667, 1996). Integration of the pzaA gene encoding the major PZase/nicotinamidase from Mycobacterium smegmatis (H. I. M. Boshoff and V. Mizrahi, J. Bacteriol. 180:5809-5814, 1998) or the M. tuberculosis pncA gene into the pncA mutant complemented its PZase/nicotinamidase defect. In both pzaA- and pncA-complemented mutant strains, the PZase activity was detected exclusively in the cytoplasm, suggesting an intracellular localization for PzaA and PncA. The pzaA-complemented strain was hypersensitive to PZA (MIC, =10 microg/ml) and nicotinamide (MIC, >/=20 microg/ml) and was also sensitive to benzamide (MIC, 20 microg/ml), unlike the wild-type and pncA-complemented mutant strains, which were highly resistant to this amide (MIC, >500 microg/ml). This finding was consistent with the observation that benzamide is hydrolyzed by PzaA but not by PncA. Overexpression of PzaA also conferred sensitivity to PZA, nicotinamide, and benzamide on M. smegmatis (MIC, 150 microg/ml in all cases) and rendered Escherichia coli hypersensitive for growth at low pH.
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Affiliation(s)
- H I Boshoff
- MRC/SAIMR/WITS Molecular Mycobacteriology Research Unit, South African Institute for Medical Research, and Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School, Johannesburg, South Africa
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Abstract
The Mycobacterium smegmatis pncA gene, encoding nicotinamidase/pyrazinamidase, was identified. While it was similar to counterparts from other mycobacteria, the M. smegmatis PncA had little homology to the other M. smegmatis pyrazinamidase/nicotinamidase, encoded by the pzaA gene. Transformation of Mycobacterium bovis strain BCG with M. smegmatis pncA or pzaA conferred susceptibility to pyrazinamide.
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Affiliation(s)
- M Guo
- Department of Molecular Microbiology and Immunology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland 21205, USA
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Zhang Y, Scorpio A, Nikaido H, Sun Z. Role of acid pH and deficient efflux of pyrazinoic acid in unique susceptibility of Mycobacterium tuberculosis to pyrazinamide. J Bacteriol 1999; 181:2044-9. [PMID: 10094680 PMCID: PMC93615 DOI: 10.1128/jb.181.7.2044-2049.1999] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide (PZA) is an important antituberculosis drug. Unlike most antibacterial agents, PZA, despite its remarkable in vivo activity, has no activity against Mycobacterium tuberculosis in vitro except at an acidic pH. M. tuberculosis is uniquely susceptible to PZA, but other mycobacteria as well as nonmycobacteria are intrinsically resistant. The role of acidic pH in PZA action and the basis for the unique PZA susceptibility of M. tuberculosis are unknown. We found that in M. tuberculosis, acidic pH enhanced the intracellular accumulation of pyrazinoic acid (POA), the active derivative of PZA, after conversion of PZA by pyrazinamidase. In contrast, at neutral or alkaline pH, POA was mainly found outside M. tuberculosis cells. PZA-resistant M. tuberculosis complex organisms did not convert PZA into POA. Unlike M. tuberculosis, intrinsically PZA-resistant M. smegmatis converted PZA into POA, but it did not accumulate POA even at an acidic pH, due to a very active POA efflux mechanism. We propose that a deficient POA efflux mechanism underlies the unique susceptibility of M. tuberculosis to PZA and that the natural PZA resistance of M. smegmatis is due to a highly active efflux pump. These findings may have implications with regard to the design of new antimycobacterial drugs.
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Affiliation(s)
- Y Zhang
- Department of Molecular Microbiology and Immunology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland 21205,
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Sun Z, Zhang Y. Reduced pyrazinamidase activity and the natural resistance of Mycobacterium kansasii to the antituberculosis drug pyrazinamide. Antimicrob Agents Chemother 1999; 43:537-42. [PMID: 10049264 PMCID: PMC89157 DOI: 10.1128/aac.43.3.537] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pyrazinamide (PZA), an analog of nicotinamide, is a prodrug that requires conversion to the bactericidal compound pyrazinoic acid (POA) by the bacterial pyrazinamidase (PZase) activity of nicotinamidase to show activity against Mycobacterium tuberculosis. Mutations leading to a loss of PZase activity cause PZA resistance in M. tuberculosis. M. kansasii is naturally resistant to PZA and has reduced PZase activity along with an apparently detectable nicotinamidase activity. The role of the reduction in PZase activity in the natural PZA resistance of M. kansasii is unknown. The MICs of PZA and POA for M. kansasii were determined to be 500 and 125 micrograms/ml, respectively. Using [14C]PZA and [14C]nicotinamide, we found that M. kansasii had about 5-fold-less PZase activity and about 25-fold-less nicotinamidase activity than M. tuberculosis. The M. kansasii pncA gene was cloned on a 1.8-kb BamHI DNA fragment, using M. avium pncA probe. Sequence analysis showed that the M. kansasii pncA gene encoded a protein with homology to its counterparts from M. tuberculosis (69.9%), M. avium (65.6%), and Escherichia coli (28.5%). Transformation of naturally PZA-resistant M. bovis BCG with M. kansasii pncA conferred partial PZA susceptibility. Transformation of M. kansasii with M. avium pncA caused functional expression of PZase and high-level susceptibility to PZA, indicating that the natural PZA resistance in M. kansasii results from a reduced PZase activity. Like M. tuberculosis, M. kansasii accumulated POA in the cells at an acidic pH; however, due to its highly active POA efflux pump, the naturally PZA-resistant species M. smegmatis did not. These findings suggest the existence of a weak POA efflux mechanism in M. kansasii.
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Affiliation(s)
- Z Sun
- Department of Molecular Microbiology and Immunology, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland 21205, USA
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Boshoff HI, Mizrahi V. Purification, gene cloning, targeted knockout, overexpression, and biochemical characterization of the major pyrazinamidase from Mycobacterium smegmatis. J Bacteriol 1998; 180:5809-14. [PMID: 9811635 PMCID: PMC107651 DOI: 10.1128/jb.180.22.5809-5814.1998] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/1998] [Accepted: 09/09/1998] [Indexed: 11/20/2022] Open
Abstract
The pyrazinamidase from Mycobacterium smegmatis was purified to homogeneity to yield a product of approximately 50 kDa. The deduced amino-terminal amino acid sequence of this polypeptide was used to design an oligonucleotide probe for screening a DNA library of M. smegmatis. An open reading frame, designated pzaA, which encodes a polypeptide of 49.3 kDa containing motifs conserved in several amidases was identified. Targeted knockout of the pzaA gene by homologous recombination yielded a mutant, pzaA::aph, with a more-than-threefold-reduced level of pyrazinamidase activity, suggesting that this gene encodes the major pyrazinamidase of M. smegmatis. Recombinant forms of the M. smegmatis PzaA and the Mycobacterium tuberculosis pyrazinamidase/nicotinamidase (PncA) were produced in Escherichia coli and were partially purified and compared in terms of their kinetics of nicotinamidase and pyrazinamidase activity. The comparable Km values obtained from this study suggested that the unique specificity of pyrazinamide (PZA) for M. tuberculosis was not based on an unusually high PZA-specific activity of the PncA protein. Overexpression of pzaA conferred PZA susceptibility on M. smegmatis by reducing the MIC of this drug to 150 micrograms/ml.
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Affiliation(s)
- H I Boshoff
- Molecular Biology Unit, South African Institute for Medical Research, and Department of Haematology, University of the Witwatersrand Medical School, Johannesburg, South Africa
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