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Demars M, McDowell T, Renaud JB, Scott A, Fruci M, Topp E. Persistence and evidence for accelerated biodegradation of streptomycin in agricultural soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 929:172502. [PMID: 38636872 DOI: 10.1016/j.scitotenv.2024.172502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 04/12/2024] [Accepted: 04/13/2024] [Indexed: 04/20/2024]
Abstract
Some antibiotics are used for the treatment of various bacterial crop diseases, and there is a concern that this practice may represent a selection pressure that increases the reservoir of antibiotic resistance carried by bacteria in crop production systems. Since the 1950s the aminoglycoside antibiotic streptomycin has been widely used for the treatment of some bacterial crop diseases such as fire blight in apples and pears. Following application, the time that bacteria will be exposed to the antibiotic, and therefore the pressure for selection of resistance, will vary according to the environmental persistence of the antibiotic. In the present study, the dissipation of streptomycin was examined in soils supplemented with 5 mg streptomycin/kg soil and incubated for 21 days under laboratory conditions. The impact of two key rate-controlling variables, soil texture (sandy loam, loam, clay loam) and temperature (4, 20, 30 °C) on streptomycin persistence were explored. -Robust methods for streptomycin extraction and analysis by LC-MS/MS were developed. Streptomycin dissipation followed first order kinetics, with the time to dissipate 50 % of the parent compound (DT50) in soils of varying texture incubated at 20 °C ranging from about seven to 15 days. In contrast, the DT50 of streptomycin in autoclaved loam soil incubated at 20 °C was about 111 days. At 4 °C the DT50 ranged from 49 to 137 days. Under no incubation conditions were any extractable transformation products obtained. Streptomycin was dissipated significantly more rapidly in field soil that had a prior history of exposure to the antibiotic than in soil that did not. Taken together, these results indicate that streptomycin is amenable to biodegradation in agricultural soils with DT50s of several days when temperature is permissive.
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Affiliation(s)
- Megan Demars
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Biology, University of Western Ontario, London, ON, Canada
| | - Tim McDowell
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Justin B Renaud
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Andrew Scott
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Michael Fruci
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
| | - Edward Topp
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Biology, University of Western Ontario, London, ON, Canada.
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2
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Perez-Bou L, Gonzalez-Martinez A, Cabrera JJ, Juarez-Jimenez B, Rodelas B, Gonzalez-Lopez J, Correa-Galeote D. Design and Validation of Primer Sets for the Detection and Quantification of Antibiotic Resistance Genes in Environmental Samples by Quantitative PCR. MICROBIAL ECOLOGY 2024; 87:71. [PMID: 38748252 PMCID: PMC11096201 DOI: 10.1007/s00248-024-02385-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 04/26/2024] [Indexed: 05/18/2024]
Abstract
The high prevalence of antibiotic resistant bacteria (ARB) in several environments is a great concern threatening human health. Particularly, wastewater treatment plants (WWTP) become important contributors to the dissemination of ARB to receiving water bodies, due to the inefficient management or treatment of highly antibiotic-concentrated wastewaters. Hence, it is vital to develop molecular tools that allow proper monitoring of the genes encoding resistances to these important therapeutic compounds (antibiotic resistant genes, ARGs). For an accurate quantification of ARGs, there is a need for sensitive and robust qPCR assays supported by a good design of primers and validated protocols. In this study, eleven relevant ARGs were selected as targets, including aadA and aadB (conferring resistance to aminoglycosides); ampC, blaTEM, blaSHV, and mecA (resistance to beta-lactams); dfrA1 (resistance to trimethoprim); ermB (resistance to macrolides); fosA (resistance to fosfomycin); qnrS (resistance to quinolones); and tetA(A) (resistance to tetracyclines). The in silico design of the new primer sets was performed based on the alignment of all the sequences of the target ARGs (orthology grade > 70%) deposited in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, allowing higher coverages of the ARGs' biodiversity than those of several primers described to date. The adequate design and performance of the new molecular tools were validated in six samples, retrieved from both natural and engineered environments related to wastewater treatment. The hallmarks of the optimized qPCR assays were high amplification efficiency (> 90%), good linearity of the standard curve (R2 > 0.980), repeatability and reproducibility across experiments, and a wide linear dynamic range. The new primer sets and methodology described here are valuable tools to upgrade the monitorization of the abundance and emergence of the targeted ARGs by qPCR in WWTPs and related environments.
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Affiliation(s)
- Lizandra Perez-Bou
- Environmental Microbiology Group, Department of Microbiology and Virology, Faculty of Biology, University of Havana, Havana, Cuba
- Microbiology and Environmental Technologies Section, Water Research Institute, University of Granada, Granada, Spain
| | - Alejandro Gonzalez-Martinez
- Microbiology and Environmental Technologies Section, Water Research Institute, University of Granada, Granada, Spain
- Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain
| | - Juan J Cabrera
- Nitrogen Metabolism Group, Zaidín Experimental Station, Spanish National Research Council, EEZ-CSIC, Granada, Spain
| | - Belen Juarez-Jimenez
- Microbiology and Environmental Technologies Section, Water Research Institute, University of Granada, Granada, Spain
- Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain
| | - Belen Rodelas
- Microbiology and Environmental Technologies Section, Water Research Institute, University of Granada, Granada, Spain
- Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain
| | - Jesus Gonzalez-Lopez
- Microbiology and Environmental Technologies Section, Water Research Institute, University of Granada, Granada, Spain
- Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain
| | - David Correa-Galeote
- Microbiology and Environmental Technologies Section, Water Research Institute, University of Granada, Granada, Spain.
- Department of Microbiology, Faculty of Pharmacy, University of Granada, Granada, Spain.
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3
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Lyu Z, Ling Y, van Hoof A, Ling J. Inactivation of the ribosome assembly factor RimP causes streptomycin resistance and impairs motility in Salmonella. Antimicrob Agents Chemother 2024:e0000224. [PMID: 38629858 DOI: 10.1128/aac.00002-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 03/27/2024] [Indexed: 05/02/2024] Open
Abstract
The ribosome is the central hub for protein synthesis and the target of many antibiotics. Although the majority of ribosome-targeting antibiotics inhibit protein synthesis and are bacteriostatic, aminoglycosides promote protein mistranslation and are bactericidal. Understanding the resistance mechanisms of bacteria against aminoglycosides is not only vital for improving the efficacy of this critically important group of antibiotics but also crucial for studying the molecular basis of translational fidelity. In this work, we analyzed Salmonella mutants evolved in the presence of the aminoglycoside streptomycin (Str) and identified a novel gene rimP to be involved in Str resistance. RimP is a ribosome assembly factor critical for the maturation of the 30S small subunit that binds Str. Deficiency in RimP increases resistance against Str and facilitates the development of even higher resistance. Deleting rimP decreases mistranslation and cellular uptake of Str and further impairs flagellar motility. Our work thus highlights a previously unknown mechanism of aminoglycoside resistance via defective ribosome assembly.
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Affiliation(s)
- Zhihui Lyu
- Department of Cell Biology and Molecular Genetics, The University of Maryland, College Park, Maryland, USA
| | - Yunyi Ling
- Department of Cell Biology and Molecular Genetics, The University of Maryland, College Park, Maryland, USA
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Jiqiang Ling
- Department of Cell Biology and Molecular Genetics, The University of Maryland, College Park, Maryland, USA
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4
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Wu Z, Li H, Wu J, Lai X, Huang S, Yu M, Liao Q, Zhang C, Zhou L, Chen X, Guo H, Chen L. The profile of genome-wide DNA methylation, transcriptome, and proteome in streptomycin-resistant Mycobacterium tuberculosis. PLoS One 2024; 19:e0297477. [PMID: 38285653 PMCID: PMC10824437 DOI: 10.1371/journal.pone.0297477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 01/06/2024] [Indexed: 01/31/2024] Open
Abstract
Streptomycin-resistant (SM-resistant) Mycobacterium tuberculosis (M. tuberculosis) is a major concern in tuberculosis (TB) treatment. However, the mechanisms underlying streptomycin resistance remain unclear. This study primarily aimed to perform preliminary screening of genes associated with streptomycin resistance through conjoint analysis of multiple genomics. Genome-wide methylation, transcriptome, and proteome analyses were used to elucidate the associations between specific genes and streptomycin resistance in M. tuberculosis H37Rv. Methylation analysis revealed that 188 genes were differentially methylated between the SM-resistant and normal groups, with 89 and 99 genes being hypermethylated and hypomethylated, respectively. Furthermore, functional analysis revealed that these 188 differentially methylated genes were enriched in 74 pathways, with most of them being enriched in metabolic pathways. Transcriptome analysis revealed that 516 genes were differentially expressed between the drug-resistant and normal groups, with 263 and 253 genes being significantly upregulated and downregulated, respectively. KEGG analysis indicated that these 516 genes were enriched in 79 pathways, with most of them being enriched in histidine metabolism. The methylation level was negatively related to mRNA abundance. Proteome analysis revealed 56 differentially expressed proteins, including 14 upregulated and 42 downregulated proteins. Moreover, three hub genes (coaE, fadE5, and mprA) were obtained using synthetic analysis. The findings of this study suggest that an integrated DNA methylation, transcriptome, and proteome analysis can provide important resources for epigenetic studies in SM-resistant M. tuberculosis H37Rv.
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Affiliation(s)
- Zhuhua Wu
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Haicheng Li
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
- The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Jiawen Wu
- Institute for tuberculosis control of Zhaoqing, Zhaoqing, China
| | - Xiaoyu Lai
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Shanshan Huang
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Meiling Yu
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Qinghua Liao
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Chenchen Zhang
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Lin Zhou
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Xunxun Chen
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Huixin Guo
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
| | - Liang Chen
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China
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5
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Lyu Z, Ling Y, van Hoof A, Ling J. Deficiency in ribosome biogenesis causes streptomycin resistance and impairs motility in Salmonella. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574728. [PMID: 38260697 PMCID: PMC10802465 DOI: 10.1101/2024.01.08.574728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The ribosome is the central hub for protein synthesis and the target of many antibiotics. Whereas the majority of ribosome-targeting antibiotics inhibit protein synthesis and are bacteriostatic, aminoglycosides promote protein mistranslation and are bactericidal. Understanding the resistance mechanisms of bacteria against aminoglycosides is not only vital for improving the efficacy of this critically important group of antibiotics but also crucial for studying the molecular basis of translational fidelity. In this work, we analyzed Salmonella mutants evolved in the presence of the aminoglycoside streptomycin (Str) and identified a novel gene rimP to be involved in Str resistance. RimP is a ribosome assembly factor critical for the maturation of the 30S small subunit that binds Str. Deficiency in RimP increases resistance against Str and facilitates the development of even higher resistance. Deleting rimP decreases mistranslation and cellular uptake of Str, and further impairs flagellar motility. Our work thus highlights a previously unknown mechanism of aminoglycoside resistance via defective ribosome assembly.
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Affiliation(s)
- Zhihui Lyu
- Department of Cell Biology and Molecular Genetics, The University of Maryland, College Park, MD 20742, USA
| | - Yunyi Ling
- Department of Cell Biology and Molecular Genetics, The University of Maryland, College Park, MD 20742, USA
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jiqiang Ling
- Department of Cell Biology and Molecular Genetics, The University of Maryland, College Park, MD 20742, USA
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Sun H, Sheng G, Xu Y, Chu H, Cao T, Dai G, Tian N, Duan H, Sun Z. Efflux pump Rv1258c activates novel functions of the oxidative stress and via the VII secretion system ESX-3-mediated iron metabolic pathway in Mycobacterium tuberculosis. Microbes Infect 2024; 26:105239. [PMID: 37863312 DOI: 10.1016/j.micinf.2023.105239] [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: 04/27/2023] [Revised: 10/08/2023] [Accepted: 10/17/2023] [Indexed: 10/22/2023]
Abstract
Oxidative stress and iron metabolism are essential for Mycobacterium tuberculosis (M.tb) survival in host cells. The efflux pump Rv1258c belongs to the major facilitator superfamily (MFS) and can actively pump drugs to promote certain drug resistance in M.tb. In this study, we compared H37RvΔRv1258c with wild-type (WT) M.tb H37Rv. The qRT-PCR results suggested that Rv1258c is potentially involved in the iron metabolic pathway by regulating the expression of ESX-3, which is required for iron uptake. Protein-Protein Affinity Predictor (PPA-Pred2) and the artificial intelligence program AlphaFold 2 were used for prediction and showed that Rv1258c has direct interactions with PPE4 and EccD3 but weak interactions with EccB3. This was further determined via protein-protein interaction analysis of the yeast two-hybrid expression system. By comparing mutant H37RvΔRv1258c strains with WT strains, we discovered that the absence of Rv1258c led to elevated intracellular H+ potential and NAD+/NADH ratios in M.tb, thereby resulting in oxidative stress. We hypothesize that the efflux pump Rv1258c not only has the function of regulating drug resistance in M.tb but also has a novel function in activating oxidative stress and regulating ESX-3-associated iron metabolism in M.tb.
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Affiliation(s)
- Hong Sun
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Gang Sheng
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Yuhui Xu
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Science, Beijing 100700, China
| | - Hongqian Chu
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Tingming Cao
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Guangming Dai
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Na Tian
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Huijuan Duan
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China
| | - Zhaogang Sun
- Translational Medicine Center, Beijing Chest Hospital, Capital Medical University, Beijing 101149, China, Beijing Key Laboratory in Drug Resistant Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China.
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7
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Morey-León G, Mejía-Ponce PM, Granda Pardo JC, Muñoz-Mawyin K, Fernández-Cadena JC, García-Moreira E, Andrade-Molina D, Licona-Cassani C, Berná L. A precision overview of genomic resistance screening in Ecuadorian isolates of Mycobacterium tuberculosis using web-based bioinformatics tools. PLoS One 2023; 18:e0294670. [PMID: 38051742 DOI: 10.1371/journal.pone.0294670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 11/07/2023] [Indexed: 12/07/2023] Open
Abstract
INTRODUCTION Tuberculosis (TB) is among the deadliest diseases worldwide, and its impact is mainly due to the continuous emergence of resistant isolates during treatment due to the laborious process of resistance diagnosis, nonadherence to treatment and circulation of previously resistant isolates of Mycobacterium tuberculosis. In this study, we evaluated the performance and functionalities of web-based tools, including Mykrobe, TB-profiler, PhyResSE, KvarQ, and SAM-TB, for detecting resistance in 88 Ecuadorian isolates of Mycobacterium tuberculosis drug susceptibility tested previously. Statistical analysis was used to determine the correlation between genomic and phenotypic analysis. Our results showed that with the exception of KvarQ, all tools had the highest correlation with the conventional drug susceptibility test (DST) for global resistance detection (98% agreement and 0.941 Cohen's kappa), while SAM-TB, PhyResSE, TB-profiler and Mykrobe had better correlations with DST for first-line drug analysis individually. We also identified that in our study, only 50% of mutations characterized by the web-based tools in the rpoB, katG, embB, pncA, gyrA and rrs regions were canonical and included in the World Health Organization (WHO) catalogue. Our findings suggest that SAM-TB, PhyResSE, TB-profiler and Mykrobe were efficient in determining canonical resistance-related mutations, but more analysis is needed to improve second-line detection. Improving surveillance programs using whole-genome sequencing tools for first-line drugs, MDR-TB and XDR-TB is essential to understand the molecular epidemiology of TB in Ecuador. IMPORTANCE Tuberculosis, an infectious disease caused by Mycobacterium tuberculosis, most commonly affects the lungs and is often spread through the air when infected people cough, sneeze, or spit. However, despite the existence of effective drug treatment, patient adherence, long duration of treatment, and late diagnosis have reduced the effectiveness of therapy and increased drug resistance. The increase in resistant cases, added to the impact of the COVID-19 pandemic, has highlighted the importance of implementing efficient and timely diagnostic methodologies worldwide. The significance of our research is in evaluating and identifying a more efficient and user-friendly web-based tool to characterize resistance in Mycobacterium tuberculosis by whole-genome sequencing, which will allow more routine application to improve TB strain surveillance programs locally.
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Affiliation(s)
- Gabriel Morey-León
- Facultad de Ciencias de la Salud, Universidad Espíritu Santo, Samborondón, Ecuador
- Universidad de la República, Montevideo, Uruguay
- University of Guayaquil, Guayaquil, Ecuador
| | - Paulina M Mejía-Ponce
- Escuela de Ingeniería y Ciencias, Tecnológico de Monterrey, Monterrey, Nuevo León, México
| | - Juan Carlos Granda Pardo
- Centro de Referencia Nacional de Micobacterias, Instituto Nacional de Investigación en Salud Pública Dr Leopoldo Izquieta Perez, INSPI-LIP, Guayaquil, Ecuador
| | - Karen Muñoz-Mawyin
- Laboratorio de Ciencias Ómicas, Universidad Espíritu Santo, Samborondón, Ecuador
| | | | | | - Derly Andrade-Molina
- Facultad de Ciencias de la Salud, Universidad Espíritu Santo, Samborondón, Ecuador
- Laboratorio de Ciencias Ómicas, Universidad Espíritu Santo, Samborondón, Ecuador
| | | | - Luisa Berná
- Laboratorio de Interacciones Hospedero-Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo, Uruguay
- Unidad de Genómica Evolutiva, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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Rao M, Wollenberg K, Harris M, Kulavalli S, Thomas L, Chawla K, Shenoy VP, Varma M, Saravu K, Hande HM, Shanthigrama Vasudeva CS, Jeffrey B, Gabrielian A, Rosenthal A. Lineage classification and antitubercular drug resistance surveillance of Mycobacterium tuberculosis by whole-genome sequencing in Southern India. Microbiol Spectr 2023; 11:e0453122. [PMID: 37671895 PMCID: PMC10580826 DOI: 10.1128/spectrum.04531-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Accepted: 07/03/2023] [Indexed: 09/07/2023] Open
Abstract
Whole-genome sequencing has created a revolution in tuberculosis management by providing a comprehensive picture of the various genetic polymorphisms with unprecedented accuracy. Studies mapping genomic heterogeneity in clinical isolates of Mycobacterium tuberculosis using a whole-genome sequencing approach from high tuberculosis burden countries are underrepresented. We report whole-genome sequencing results of 242 clinical isolates of culture-confirmed M. tuberculosis isolates from tuberculosis patients referred to a tertiary care hospital in Southern India. Phylogenetic analysis revealed that the isolates in our study belonged to five different lineages, with Indo-Oceanic (lineage 1, n = 122) and East-African Indian (lineage 3, n = 80) being the most prevalent. We report several mutations in genes conferring resistance to first and second line antitubercular drugs including the genes rpoB, katG, ahpC, inhA, fabG1, embB, pncA, rpsL, rrs, and gyrA. The majority of these mutations were identified in relatively high proportions in lineage 1. Our study highlights the utility of whole-genome sequencing as a potential supplemental tool to the existing genotypic and phenotypic methods, in providing expedited comprehensive surveillance of mutations that may be associated with antitubercular drug resistance as well as lineage characterization of M. tuberculosis isolates. Further larger-scale whole-genome datasets with linked minimum inhibition concentration testing are imperative for resolving the discrepancies between whole-genome sequencing and phenotypic drug sensitivity testing results and quantifying the level of the resistance associated with the mutations for optimization of antitubercular drug and precise dose selection in clinics. IMPORTANCE Studies mapping genetic heterogeneity of clinical isolates of M. tuberculosis for determining their strain lineage and drug resistance by whole-genome sequencing are limited in high tuberculosis burden settings. We carried out whole-genome sequencing of 242 M. tuberculosis isolates from drug-sensitive and drug-resistant tuberculosis patients, identified and collected as part of the TB Portals Program, to have a comprehensive insight into the genetic diversity of M. tuberculosis in Southern India. We report several genetic variations in M. tuberculosis that may confer resistance to antitubercular drugs. Further wide-scale efforts are required to fully characterize M. tuberculosis genetic diversity at a population level in high tuberculosis burden settings for providing precise tuberculosis treatment.
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Affiliation(s)
- Mahadev Rao
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Kurt Wollenberg
- Department of Health and Human Services, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Michael Harris
- Department of Health and Human Services, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Shrivathsa Kulavalli
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Levin Thomas
- Department of Pharmacy Practice, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Kiran Chawla
- Department of Microbiology, Kasturba Medical College, Manipal, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Vishnu Prasad Shenoy
- Department of Microbiology, Kasturba Medical College, Manipal, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Muralidhar Varma
- Department of Infectious Diseases, Kasturba Medical College, Manipal, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - Kavitha Saravu
- Department of Infectious Diseases, Kasturba Medical College, Manipal, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | - H. Manjunatha Hande
- Department of Medicine, Kasturba Medical College, Manipal, Manipal Academy of Higher Education (MAHE), Manipal, Karnataka, India
| | | | - Brendan Jeffrey
- Department of Health and Human Services, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Andrei Gabrielian
- Department of Health and Human Services, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Alex Rosenthal
- Department of Health and Human Services, Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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9
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Wang S, Luan J, Chen L, Liu H, Li W, Wang J. Computational characteristics of the structure-activity relationship of inhibitors targeting Pks13-TE domain. Comput Biol Chem 2023; 104:107864. [PMID: 37028177 DOI: 10.1016/j.compbiolchem.2023.107864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 03/22/2023] [Accepted: 04/01/2023] [Indexed: 04/09/2023]
Abstract
Multiple studies have established the Pks13-TE domain as a promising target for anti-tuberculosis drug development. However, recent findings have revealed that the lead compound currently in the pipeline for Pks13-TE has significant cardiotoxicity issues. Given the pressing need for new chemical structures for Pks13-TE inhibitors, this study aims to provide a detailed understanding of the Pks13-TE domain binding site through the application of computational chemical biology techniques. Our results highlight the size and shape of the Pks13-TE domain binding pocket, key residues including Asp1644, Asn1640, Phe1670, and Tyr1674 within the pocket, and inhibitor pharmacophore characteristics such as aromatic ring sites, positively charged sites, and hydrogen bond donors. To our knowledge, these simulation results are novel and contribute to the discovery of next-generation Pks13-TE inhibitors without similar prior studies.
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Affiliation(s)
- Shizun Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Jiasi Luan
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Medical Devices, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Lu Chen
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Haihan Liu
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Weixia Li
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Jian Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China; Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China; School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, China.
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10
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Vatlin AA, Bekker OB, Shur KV, Ilyasov RA, Shatrov PA, Maslov DA, Danilenko VN. Kanamycin and Ofloxacin Activate the Intrinsic Resistance to Multiple Antibiotics in Mycobacterium smegmatis. BIOLOGY 2023; 12:biology12040506. [PMID: 37106707 PMCID: PMC10135989 DOI: 10.3390/biology12040506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/16/2023] [Accepted: 03/25/2023] [Indexed: 03/30/2023]
Abstract
Drug resistance (DR) in Mycobacterium tuberculosis is the main problem in fighting tuberculosis (TB). This pathogenic bacterium has several types of DR implementation: acquired and intrinsic DR. Recent studies have shown that exposure to various antibiotics activates multiple genes, including genes responsible for intrinsic DR. To date, there is evidence of the acquisition of resistance at concentrations well below the standard MICs. In this study, we aimed to investigate the mechanism of intrinsic drug cross-resistance induction by subinhibitory concentrations of antibiotics. We showed that pretreatment of M. smegmatis with low doses of antibiotics (kanamycin and ofloxacin) induced drug resistance. This effect may be caused by a change in the expression of transcriptional regulators of the mycobacterial resistome, in particular the main transcriptional regulator whiB7.
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11
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Dasoondi RS, Blundell TL, Pandurangan AP. In silico analyses of isoniazid and streptomycin resistance-associated mutations in Mycobacterium tuberculosis. Comput Struct Biotechnol J 2023; 21:1874-1884. [PMID: 36915381 PMCID: PMC10006719 DOI: 10.1016/j.csbj.2023.02.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 02/18/2023] [Accepted: 02/18/2023] [Indexed: 02/23/2023] Open
Abstract
Multi-drug resistant tuberculosis is categorised by the World Health Organisation (WHO) as a public health crisis. In silico techniques were used to probe the structural basis of Mycobacterium tuberculosis resistance to isoniazid and streptomycin. Isoniazid resistance-associated mutations in InhA were predicted to reduce the binding affinity of NADH to InhA, without affecting INH-NAD (competitive-inhibitor) binding. Perturbation of the mutated residues was predicted (with the AlloSigMA server) to modulate the free energy of allosteric modulation of key binding site residues F41, F149, Y158 and W222. These results suggest that allosteric modulation of the protein structure may be key to the mechanism by which isoniazid resistance-associated mutations act. Mutations in the methyltransferase glucose-inhibited division gene B (GidB) are associated with streptomycin resistance. Molecular docking was carried out to predict the structure of the GidB bound to its substrate (s-adenosyl methionine). The effects of streptomycin resistance-associated mutations in GidB on protein stability and substrate binding were predicted (using SDM and mCSM-lig). All GidB mutants were predicted to disfavour SAM binding.
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Affiliation(s)
| | - Tom L Blundell
- Department of Biochemistry, University of Cambridge, United Kingdom
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12
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Morey-León G, Andrade-Molina D, Fernández-Cadena JC, Berná L. Comparative genomics of drug-resistant strains of Mycobacterium tuberculosis in Ecuador. BMC Genomics 2022; 23:844. [PMID: 36544084 PMCID: PMC9769008 DOI: 10.1186/s12864-022-09042-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 11/23/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Tuberculosis is a serious infectious disease affecting millions of people. In spite of efforts to reduce the disease, increasing antibiotic resistance has contributed to persist in the top 10 causes of death worldwide. In fact, the increased cases of multi (MDR) and extreme drug resistance (XDR) worldwide remains the main challenge for tuberculosis control. Whole genome sequencing is a powerful tool for predicting drug resistance-related variants, studying lineages, tracking transmission, and defining outbreaks. This study presents the identification and characterization of resistant clinical isolates of Mycobacterium tuberculosis including a phylogenetic and molecular resistance profile study by sequencing the complete genome of 24 strains from different provinces of Ecuador. RESULTS Genomic sequencing was used to identify the variants causing resistance. A total of 15/21 isolates were identified as MDR, 4/21 as pre-XDR and 2/21 as XDR, with three isolates discarded due to low quality; the main sub-lineage was LAM (61.9%) and Haarlem (19%) but clades X, T and S were identified. Of the six pre-XDR and XDR strains, it is noteworthy that five come from females; four come from the LAM sub-lineage and two correspond to the X-class sub-lineage. A core genome of 3,750 genes, distributed in 295 subsystems, was determined. Among these, 64 proteins related to virulence and implicated in the pathogenicity of M. tuberculosis and 66 possible pharmacological targets stand out. Most variants result in nonsynonymous amino acid changes and the most frequent genotypes were identified as conferring resistance to rifampicin, isoniazid, ethambutol, para-aminosalicylic acid and streptomycin. However, an increase in the resistance to fluoroquinolones was detected. CONCLUSION This work shows for the first time the variability of circulating resistant strains between men and women in Ecuador, highlighting the usefulness of genomic sequencing for the identification of emerging resistance. In this regard, we found an increase in fluoroquinolone resistance. Further sampling effort is needed to determine the total variability and associations with the metadata obtained to generate better health policies.
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Affiliation(s)
- Gabriel Morey-León
- grid.418532.90000 0004 0403 6035Laboratorio de Interacciones Hospedero-Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo, Uruguay ,grid.442157.10000 0001 1183 0630Universidad de Guayaquil, Guayaquil, Ecuador ,grid.442156.00000 0000 9557 7590Facultad de Ciencias de la Salud, Universidad Espíritu Santo, Samborondón, Ecuador
| | - Derly Andrade-Molina
- grid.442156.00000 0000 9557 7590Laboratorio de Ciencias Ómicas, Universidad Espíritu Santo, Samborondón, Ecuador
| | - Juan Carlos Fernández-Cadena
- grid.442156.00000 0000 9557 7590Laboratorio de Ciencias Ómicas, Universidad Espíritu Santo, Samborondón, Ecuador
| | - Luisa Berná
- grid.418532.90000 0004 0403 6035Laboratorio de Interacciones Hospedero-Patógeno, Unidad de Biología Molecular, Institut Pasteur de Montevideo, Montevideo, Uruguay ,grid.11630.350000000121657640Facultad de Ciencias, Unidad de Genómica Evolutiva, Universidad de La República, Montevideo, Uruguay
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13
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Faille A, Warren AJ. Teaching old drugs new tricks. eLife 2022; 11:e84702. [PMID: 36480270 PMCID: PMC9731568 DOI: 10.7554/elife.84702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Understanding the mechanism by which streptomycin binds to the small subunit of the mitoribosome may help researchers design less toxic derivatives of this antibiotic.
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Affiliation(s)
- Alexandre Faille
- Cambridge Institute for Medical Research, University of CambridgeCambridgeUnited Kingdom
| | - Alan J Warren
- The Department of Haematology, University of CambridgeCambridgeUnited Kingdom
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of CambridgeCambridgeUnited Kingdom
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14
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Nasiri A, Mokhtari S, Daraei B, Yazdanpanah H, Faizi M, Kobarfard F. A Neglected Challenge in the Analysis of Active Pharmaceutical Substances with Aldehyde Functional Group in Aqueous Matrices. IRANIAN JOURNAL OF PHARMACEUTICAL RESEARCH : IJPR 2022; 21:e127036. [PMID: 36060912 PMCID: PMC9420214 DOI: 10.5812/ijpr-127036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/05/2022] [Indexed: 06/15/2023]
Abstract
Aldehydes are compounds that are widely used and popular in organic synthesis due to their high reactivity. This advantage is a disadvantage in medicinal chemistry. Due to the ability of aldehydes to participate in nucleophilic reactions (especially in aqueous biological media) and access to nucleophiles such as amino acids and nucleic acids, drugs with aldehyde functional groups are always used with caution and carefully quantified in biological fluids. Our experience in working on biologically active aldehydes indicates the transformation of these groups of compounds in aqueous or alcoholic solution and thus the failure of analytical methods for their accurate monitoring in such media. Both mass spectrometry and Proton nuclear magnetic resonance spectroscopic findings indicate the reaction of spiramycin with water molecules in an aqueous solution, resulting in the conversion of spiramycin to a new molecule with 18 mass unit difference and thus, the residue amount which is measured and reported based on a mass spectrometries method does not show the correct amount of spiramycin in these samples.
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Affiliation(s)
- Azadeh Nasiri
- Department of Pharmacology and Toxicology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Food Safety Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shaya Mokhtari
- Central Research Laboratories, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Bahram Daraei
- Department of Pharmacology and Toxicology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hassan Yazdanpanah
- Department of Pharmacology and Toxicology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Food Safety Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mehrdad Faizi
- Department of Pharmacology and Toxicology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farzad Kobarfard
- Department of Medicinal Chemistry, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Central Research Laboratories, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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15
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Mhazo AT, Maponga CC. Framing access to essential medicines in the context of Universal Health Coverage: a critical analysis of health sector strategic plans from eight countries in the WHO African region. BMC Health Serv Res 2022; 22:1390. [PMID: 36419062 PMCID: PMC9682662 DOI: 10.1186/s12913-022-08791-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 11/04/2022] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Framing affects how issues are understood and portrayed. This profoundly shapes the construction of social problems and how policy options are considered. While access to essential medicines (ATM) in the World Health Organization (WHO) African Region is often framed as a societal problem, there is dominance of medical and technically oriented approaches to analyze and remedy the situation. Hence, the systematic application of social science approaches, such as framing theory, remains under-explored. Through a framing analysis of National Strategic Plans (NSPs) from eight countries, this study explores the applicability and potential usefulness of framing theory to analyze essential medicines policies. METHODS We inductively coded the relevant NSP textual fragments using the qualitative content analysis software ATLAS.ti.22. Benford and Snow's conceptualization of framing was used to organize the coded data into three frames: diagnostic (problems), prognostic (solutions) and motivational (values and ideological). RESULTS The following five diagnostic frames were dominant or in-frame: medicine unavailability, ineffective regulation, weak supply chain management, proliferation of counterfeit (substandard or falsified) medicines and use of poor quality medicines. Diagnostic frames related to financing, affordability, efficiency and corruption were given limited coverage or out of frame. Prognostic frames corresponded with how these problems were framed. Whilst Universal Health Coverage (UHC) and its guiding principles was the dominant motivational frame, we identified some frame discordance between the global discourse and national level policies. CONCLUSIONS Social science approaches such as framing analysis are applicable and useful to systematically analyze essential medicine aspects. By applying framing theory, we revealed that ATM aspects in the eight countries we analyzed are more often characterized in relation to availability at the expense of affordability which undermines UHC. We conclude that whilst UHC is a strong motivational frame to guide ATM aspects, it is insufficient to inform a comprehensive approach to address the problems related to ATM at country level. To effectively advance ATM, concerned actors need to realize such limitation and endeavor to gain a deeper understanding of how problems are framed and agendas are set at country level, the processes through which ideas and knowledge become policies, including the political demands, incentives and trade-offs facing decision-makers in selecting policy priorities.
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Affiliation(s)
- Alison T. Mhazo
- grid.415722.70000 0004 0598 3405Ministry of Health, Community Health Sciences Unit (CHSU), Private Bag 65, Area 3, Lilongwe, Malawi
| | - Charles C. Maponga
- grid.13001.330000 0004 0572 0760Department of Pharmacy and Pharmaceutical Sciences, Faculty of Medicine and Health Sciences, University of Zimbabwe, Avondale, P. O. Box A178, Harare, Zimbabwe
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16
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Stanley S, Liu Q, Fortune SM. Mycobacterium tuberculosis functional genetic diversity, altered drug sensitivity, and precision medicine. Front Cell Infect Microbiol 2022; 12:1007958. [PMID: 36262182 PMCID: PMC9574059 DOI: 10.3389/fcimb.2022.1007958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 09/14/2022] [Indexed: 01/27/2023] Open
Abstract
In the face of the unrelenting global burden of tuberculosis (TB), antibiotics remain our most effective tools to save lives and control the spread of Mycobacterium tuberculosis (Mtb). However, we confront a dual challenge in our use of antibiotics: simplifying and shortening the TB drug regimen while also limiting the emergence and propagation of antibiotic resistance. This task is now more feasible due to the increasing availability of bacterial genomic data at or near the point of care. These resources create an opportunity to envision how integration of bacterial genetic determinants of antibiotic response into treatment algorithms might transform TB care. Historically, Mtb drug resistance studies focused on mutations in genes encoding antibiotic targets and the resulting increases in the minimal inhibitory concentrations (MICs) above a breakpoint value. But recent progress in elucidating the effects of functional genetic diversity in Mtb has revealed various genetic loci that are associated with drug phenotypes such as low-level MIC increases and tolerance which predict the development of resistance and treatment failure. As a result, we are now poised to advance precision medicine approaches in TB treatment. By incorporating information regarding Mtb genetic characteristics into the development of drug regimens, clinical care which tailors antibiotic treatment to maximize the likelihood of success has come into reach.
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Affiliation(s)
- Sydney Stanley
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - Qingyun Liu
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, United States
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17
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Experimental confirmation that an uncommon
rrs
gene mutation (g878a) of
Mycobacterium tuberculosis
confers resistance to streptomycin. Antimicrob Agents Chemother 2022; 66:e0191521. [DOI: 10.1128/aac.01915-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effective treatment of patients diagnosed with drug resistant tuberculosis is highly dependent upon the ability to rapidly and accurately determine the antibiotic susceptibility profile of the
Mycobacterium tuberculosis
isolate(s) involved. Thus, as more clinical microbiology laboratories advance towards the use of DNA sequence-based diagnostics, it is imperative that their predictive functions extend beyond the well-known resistance mutations, in order to also encompass as many of the lower-frequency mutations as possible. However, in most cases, the fundamental experimental proof that links these uncommon mutations with phenotypic resistance is lacking. One such example is the g878a polymorphism within the
rrs
16s rRNA gene. We, and others, have identified this mutation within a small number of drug-resistant isolates, although a consensus regarding exactly which aminoglycoside antibiotic(s) it confers resistance toward has not previously been reached. Here we have employed oligo-mediated recombineering to introduce the g878a polymorphism into the
rrs
gene of
M. bovis
BCG - a close relative of
M. tuberculosis
- and demonstrate that it confers low-level resistance to streptomycin alone. It does not confer cross-resistance towards amikacin, capreomycin, nor kanamycin. We also demonstrate that the
rrs
g878a
mutation exerts a substantial fitness defect
in vitro
, that may at least in part explain why clinical isolates bearing this mutation appear to be quite rare. Overall, this study provides clarity to the phenotype attributable to the
rrs
g878a
mutation and is relevant to the future implementation of genomics-based diagnostics, as well as the clinical management of patients where this particular polymorphism is encountered.
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18
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Duboux S, Ngom-Bru C, De Bruyn F, Bogicevic B. Phylogenetic, Functional and Safety Features of 1950s B. infantis Strains. Microorganisms 2022; 10:microorganisms10020203. [PMID: 35208658 PMCID: PMC8879182 DOI: 10.3390/microorganisms10020203] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 02/05/2023] Open
Abstract
Strains of Bifidobacterium longum subsp. infantis (B. infantis) are amongst the first to colonize the infant gut, partly due to their capacity to metabolize complex human milk oligosaccharides (HMO), and are proposed to play a key role in the development of the infant gut. Since early life, B. infantis supplementation is of high interest, and detailed phylogenetic, functional and safety characterization of the selected strains should be pursued. Using a combination of long and short-read sequencing technologies, we first decipher the genetic distance between different isolates of the same B. infantis strain. Using the same approach, we show that several publicly available genomes recapitulate this strain-level distance as compared to two of the first strains obtained in the 1950s. Furthermore, we demonstrate that the two 1950s B. infantis strains display different functional and safety attributes, as ATCC 15697 is resistant to streptomycin and shows a preference towards lacto-N-tetraose LNT and sialylated HMOs, while LMG 11588 is sensitive to all tested antibiotics and shows a preference towards fucosylated HMOs. Overall, our work highlights that the current diversity observed in B. infantis is likely underestimated and that strain selection within this subspecies must be the subject of scientific pursuit and associated evaluation.
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Affiliation(s)
- Stéphane Duboux
- Société des Produits Nestlé SA, Nestlé Research, Route du Jorat 57, CH-1000 Lausanne 26, Switzerland; (C.N.-B.); (B.B.)
- Correspondence:
| | - Catherine Ngom-Bru
- Société des Produits Nestlé SA, Nestlé Research, Route du Jorat 57, CH-1000 Lausanne 26, Switzerland; (C.N.-B.); (B.B.)
| | - Florac De Bruyn
- Société des Produits Nestlé SA, Nestlé Research & Development, Nestléstrasse 3, CH-3510 Konolfingen, Switzerland;
| | - Biljana Bogicevic
- Société des Produits Nestlé SA, Nestlé Research, Route du Jorat 57, CH-1000 Lausanne 26, Switzerland; (C.N.-B.); (B.B.)
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19
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The Neglected Contribution of Streptomycin to the Tuberculosis Drug Resistance Problem. Genes (Basel) 2021; 12:genes12122003. [PMID: 34946952 PMCID: PMC8701281 DOI: 10.3390/genes12122003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 12/22/2022] Open
Abstract
The airborne pathogen Mycobacterium tuberculosis is responsible for a present major public health problem worsened by the emergence of drug resistance. M. tuberculosis has acquired and developed streptomycin (STR) resistance mechanisms that have been maintained and transmitted in the population over the last decades. Indeed, STR resistant mutations are frequently identified across the main M. tuberculosis lineages that cause tuberculosis outbreaks worldwide. The spread of STR resistance is likely related to the low impact of the most frequent underlying mutations on the fitness of the bacteria. The withdrawal of STR from the first-line treatment of tuberculosis potentially lowered the importance of studying STR resistance. However, the prevalence of STR resistance remains very high, could be underestimated by current genotypic methods, and was found in outbreaks of multi-drug (MDR) and extensively drug (XDR) strains in different geographic regions. Therefore, the contribution of STR resistance to the problem of tuberculosis drug resistance should not be neglected. Here, we review the impact of STR resistance and detail well-known and novel candidate STR resistance mechanisms, genes, and mutations. In addition, we aim to provide insights into the possible role of STR resistance in the development of multi-drug resistant tuberculosis.
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20
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Wastewater-Based Surveillance of Antibiotic Resistance Genes Associated with Tuberculosis Treatment Regimen in KwaZulu Natal, South Africa. Antibiotics (Basel) 2021; 10:antibiotics10111362. [PMID: 34827300 PMCID: PMC8614817 DOI: 10.3390/antibiotics10111362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/15/2021] [Accepted: 10/28/2021] [Indexed: 12/15/2022] Open
Abstract
Essential components of public health include strengthening the surveillance of infectious diseases and developing early detection and prevention policies. This is particularly important for drug-resistant tuberculosis (DR-TB), which can be explored by using wastewater-based surveillance. This study aimed to use molecular techniques to determine the occurrence and concentration of antibiotic-resistance genes (ARGs) associated with tuberculosis (TB) resistance in untreated and treated wastewater. Raw/untreated and treated (post-chlorination) wastewater samples were taken from three wastewater treatment plants (WWTPs) in South Africa. The ARGs were selected to target drugs used for first- and second-line TB treatment. Both conventional polymerase chain reaction (PCR) and the more advanced droplet digital PCR (ddPCR) were evaluated as surveillance strategies to determine the distribution and concentration of the selected ARGs. The most abundant ARG in the untreated wastewater was the rrs gene, associated with resistance to the aminoglycosides, specifically streptomycin, with median concentration ranges of 4.69–5.19 log copies/mL. In contrast, pncA gene, associated with resistance to the TB drug pyrazinamide, was the least detected (1.59 to 2.27 log copies/mL). Resistance genes associated with bedaquiline was detected, which is a significant finding because this is a new drug introduced in South Africa for the treatment of multi-drug resistant TB. This study, therefore, establishes the potential of molecular surveillance of wastewater for monitoring antibiotic resistance to TB treatment in communities.
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21
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Characterization of Mutations Associated with Streptomycin Resistance in Multidrug-Resistant Mycobacterium tuberculosis in Zambia. Antibiotics (Basel) 2021; 10:antibiotics10101169. [PMID: 34680750 PMCID: PMC8532810 DOI: 10.3390/antibiotics10101169] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/17/2021] [Accepted: 09/20/2021] [Indexed: 11/17/2022] Open
Abstract
Streptomycin (STR) is recommended for the management of multidrug-resistant tuberculosis (MDR-TB). Streptomycin resistance-conferring mutation types and frequency are shown to be influenced by genotypes of circulating strains in a population. This study aimed to characterize the mutations in MDR-TB isolates and examine their relationship with the genotypes in Zambia. A total of 138 MDR-TB isolates stored at the University Teaching Hospital Tuberculosis Reference Laboratory in Zambia were analyzed using spoligotyping and sequencing of STR resistance-associated genes. Streptomycin resistance was observed in 65.9% (91/138) of MDR-TB isolates. Mutations in rpsL, rrs, and gidB accounted for 33%, 12.1%, and 49.5%, respectively. Amino acid substitution K43R in rpsL was strongly associated with the CAS1_Kili genotype (p < 0.0001). The combination of three genes could predict 91.2% of STR resistance. Clustering of isolates based on resistance-conferring mutations and spoligotyping was observed. The clustering of isolates suggests that the increase in STR-resistant MDR-TB in Zambia is largely due to the spread of resistant strains from inadequate treatment. Therefore, rapid detection of STR resistance genetically is recommended before its use in MDR-TB treatment in Zambia.
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22
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Ngoc NB, Vu Dinh H, Thuy NT, Quang DV, Huyen CTT, Hoa NM, Anh NH, Dat PT, Hoa NB, Tiemersma E, Nhung NV. Active surveillance for adverse events in patients on longer treatment regimens for multidrug-resistant tuberculosis in Viet Nam. PLoS One 2021; 16:e0255357. [PMID: 34492031 PMCID: PMC8423256 DOI: 10.1371/journal.pone.0255357] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/14/2021] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Management of multidrug-resistant tuberculosis (MDR-TB) is a significant challenge to the global healthcare system due to the complexity and long duration of the MDR-TB treatment. This study analyzed the safety of patients on longer injectable-based MDR-TB treatment regimens using active pharmacovigilance data. METHOD We conducted an observational, prospective study based on active pharmacovigilance within the national TB program. A total of 659 MDR-TB patients were enrolled and followed up at 9 TB- hospitals in 9 provinces of all 3 regions in Vietnam between 2014 and 2016. Patients received a treatment regimen (standardized or individualized) based on their drug susceptibility test result and their treatment history. Baseline and follow-up information was collected at the start and during treatment. Adverse events (AE) were defined and classified as serious adverse events (SAEs) or otherwise. Multivariate Cox regression following the Iterative Bayesian Model Averaging algorithm was performed to identify factors associated with AE occurrence. RESULTS Out of 659 patients assessed, 71.3% experienced at least one AE, and 17.5% suffered at least one SAE. The most common AEs were gastrointestinal disorders (38.5%), arthralgia (34.7%), and psychiatric disorders (30.0%). The proportion of patients with nephrotoxicity and hearing loss or vestibular disorders were 7.4% and 15.2%, respectively. 13.1% of patients required modifications or interruption of one or more drugs. In 77.7% of patients, treatment was completed successfully, while 9.3% lost to follow-up, in 3.0% treatment failed, and 7.4% died. Some significant risk factors for nephrotoxicity included diabetes mellitus (HR = 8.46 [1.91-37.42]), renal dysfunction (HR = 8.46 [1.91-37.42]), alcoholism (HR = 13.28 [5.04-34.99]), and a higher average daily dose of injectable drugs (HR = 1.28 [1.14-1.43]). CONCLUSION While a majority of patients on the longer injectable-based regimens experienced non-serious AEs during MDR-TB treatment, one in six patients experienced at least an SAE. Active TB drug-safety monitoring is useful to understand the safety of MDR-TB treatment and explore the risk factors for toxicity. All-oral, shorter MDR-TB regimens might be able to reduce the inconvenience, discomfort, and toxicity of such regimens and increase adherence and likelihood of successful completion.
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Affiliation(s)
- Nguyen Bao Ngoc
- National Tuberculosis Programme, Hanoi, Viet Nam
- Department of Pharmacy, National Lung Hospital, Hanoi, Viet Nam
- National Drug Information and Adverse Drug Reaction Monitoring Centre, Hanoi University of Pharmacy, Hanoi, Viet Nam
| | - Hoa Vu Dinh
- National Drug Information and Adverse Drug Reaction Monitoring Centre, Hanoi University of Pharmacy, Hanoi, Viet Nam
| | - Nguyen Thi Thuy
- National Tuberculosis Programme, Hanoi, Viet Nam
- Department of Pharmacy, National Lung Hospital, Hanoi, Viet Nam
| | - Duong Van Quang
- National Drug Information and Adverse Drug Reaction Monitoring Centre, Hanoi University of Pharmacy, Hanoi, Viet Nam
| | - Cao Thi Thu Huyen
- National Drug Information and Adverse Drug Reaction Monitoring Centre, Hanoi University of Pharmacy, Hanoi, Viet Nam
| | - Nguyen Mai Hoa
- National Drug Information and Adverse Drug Reaction Monitoring Centre, Hanoi University of Pharmacy, Hanoi, Viet Nam
| | - Nguyen Hoang Anh
- National Drug Information and Adverse Drug Reaction Monitoring Centre, Hanoi University of Pharmacy, Hanoi, Viet Nam
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23
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Molecular Analysis of Streptomycin Resistance Genes in Clinical Strains of Mycobacterium tuberculosis and Biocomputational Analysis of the MtGidB L101F Variant. Antibiotics (Basel) 2021; 10:antibiotics10070807. [PMID: 34356728 PMCID: PMC8300841 DOI: 10.3390/antibiotics10070807] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 12/30/2022] Open
Abstract
Globally, tuberculosis (TB) remains a prevalent threat to public health. In 2019, TB affected 10 million people and caused 1.4 million deaths. The major challenge for controlling this infectious disease is the emergence and spread of drug-resistant Mycobacterium tuberculosis, the causative agent of TB. The antibiotic streptomycin is not a current first-line anti-TB drug. However, WHO recommends its use in patients infected with a streptomycin-sensitive strain. Several mutations in the M. tuberculosisrpsL, rrs and gidB genes have proved association with streptomycin resistance. In this study, we performed a molecular analysis of these genes in clinical isolates to determine the prevalence of known or novel mutations. Here, we describe the genetic analysis outcome. Furthermore, a biocomputational analysis of the MtGidB L101F variant, the product of a novel mutation detected in gidB during molecular analysis, is also reported as a theoretical approach to study the apparent genotype-phenotype association.
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Rocha DMGC, Magalhães C, Cá B, Ramos A, Carvalho T, Comas I, Guimarães JT, Bastos HN, Saraiva M, Osório NS. Heterogeneous Streptomycin Resistance Level Among Mycobacterium tuberculosis Strains From the Same Transmission Cluster. Front Microbiol 2021; 12:659545. [PMID: 34177837 PMCID: PMC8226182 DOI: 10.3389/fmicb.2021.659545] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 05/06/2021] [Indexed: 11/13/2022] Open
Abstract
Widespread and frequent resistance to the second-line tuberculosis (TB) medicine streptomycin, suggests ongoing transmission of low fitness cost streptomycin resistance mutations. To investigate this hypothesis, we studied a cohort of 681 individuals from a TB epidemic in Portugal. Whole-genome sequencing (WGS) analyses were combined with phenotypic growth studies in culture media and in mouse bone marrow derived macrophages. Streptomycin resistance was the most frequent resistance in the cohort accounting for 82.7% (n = 67) of the resistant Mycobacterium tuberculosis isolates. WGS of 149 clinical isolates identified 13 transmission clusters, including three clusters containing only streptomycin resistant isolates. The biggest cluster was formed by eight streptomycin resistant isolates with a maximum of five pairwise single nucleotide polymorphisms of difference. Interestingly, despite their genetic similarity, these isolates displayed different resistance levels to streptomycin, as measured both in culture media and in infected mouse bone marrow derived macrophages. The genetic bases underlying this phenotype are a combination of mutations in gid and other genes. This study suggests that specific streptomycin resistance mutations were transmitted in the cohort, with the resistant isolates evolving at the cluster level to allow low-to-high streptomycin resistance levels without a significative fitness cost. This is relevant not only to better understand transmission of streptomycin resistance in a clinical setting dominated by Lineage 4 M. tuberculosis infections, but mainly because it opens new prospects for the investigation of selection and spread of drug resistance in general.
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Affiliation(s)
- Deisy M G C Rocha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga, Portugal.,i3S - Instituto de Investigacão e Inovação em Saúde, University of Porto, Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto, Portugal
| | - Carlos Magalhães
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga, Portugal
| | - Baltazar Cá
- i3S - Instituto de Investigacão e Inovação em Saúde, University of Porto, Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto, Portugal
| | - Angelica Ramos
- Department of Clinical Pathology, Centro Hospitalar São João, Porto, Portugal
| | - Teresa Carvalho
- Department of Clinical Pathology, Centro Hospitalar São João, Porto, Portugal
| | - Iñaki Comas
- Biomedicine Institute of Valencia IBV-CSIC, Valencia, Spain.,CIBER in Epidemiology and Public Health, Valencia, Spain
| | - João Tiago Guimarães
- Department of Clinical Pathology, Centro Hospitalar São João, Porto, Portugal.,Institute of Public Health, University of Porto, Porto, Portugal.,Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Helder Novais Bastos
- i3S - Instituto de Investigacão e Inovação em Saúde, University of Porto, Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto, Portugal.,Serviço de Pneumologia, Centro Hospitalar Universitário de São João EPE, Porto, Portugal
| | - Margarida Saraiva
- i3S - Instituto de Investigacão e Inovação em Saúde, University of Porto, Porto, Portugal.,Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Porto, Portugal
| | - Nuno S Osório
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal.,ICVS/3B's - PT Government Associate Laboratory, Braga, Portugal
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Antimicrobial Peptides as Potential Anti-Tubercular Leads: A Concise Review. Pharmaceuticals (Basel) 2021; 14:ph14040323. [PMID: 33918182 PMCID: PMC8065624 DOI: 10.3390/ph14040323] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 12/11/2022] Open
Abstract
Despite being considered a public health emergency for the last 25 years, tuberculosis (TB) is still one of the deadliest infectious diseases, responsible for over a million deaths every year. The length and toxicity of available treatments and the increasing emergence of multidrug-resistant strains of Mycobacterium tuberculosis renders standard regimens increasingly inefficient and emphasizes the urgency to develop new approaches that are not only cost- and time-effective but also less toxic. Antimicrobial peptides (AMP) are small cationic and amphipathic molecules that play a vital role in the host immune system by acting as a first barrier against invading pathogens. The broad spectrum of properties that peptides possess make them one of the best possible alternatives for a new “post-antibiotic” era. In this context, research into AMP as potential anti-tubercular agents has been driven by the increasing danger revolving around the emergence of extremely-resistant strains, the innate resistance that mycobacteria possess and the low compliance of patients towards the toxic anti-TB treatments. In this review, we will focus on AMP from various sources, such as animal, non-animal and synthetic, with reported inhibitory activity towards Mycobacterium tuberculosis.
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Cantillon D, Wroblewska J, Cooper I, Newport MJ, Waddell SJ. Three-dimensional low shear culture of Mycobacterium bovis BCG induces biofilm formation and antimicrobial drug tolerance. NPJ Biofilms Microbiomes 2021; 7:12. [PMID: 33526771 PMCID: PMC7851154 DOI: 10.1038/s41522-021-00186-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 01/07/2021] [Indexed: 01/30/2023] Open
Abstract
Mycobacteria naturally grow as corded biofilms in liquid media without detergent. Such detergent-free biofilm phenotypes may reflect the growth pattern of bacilli in tuberculous lung lesions. New strategies are required to treat tuberculosis, which is responsible for more deaths each year than any other bacterial disease. The lengthy 6-month regimen for drug-sensitive tuberculosis is necessary to remove antimicrobial drug tolerant populations of bacilli that persist through drug therapy. The role of biofilm-like growth in the generation of these sub-populations remains poorly understood despite the hypothesised clinical significance and mounting evidence of biofilms in pathogenesis. We adapt a three-dimensional Rotary Cell Culture System to model M. bovis BCG biofilm growth in low-shear detergent-free liquid suspension. Importantly, biofilms form without attachment to artificial surfaces and without severe nutrient starvation or environmental stress. Biofilm-derived planktonic bacilli are tolerant to isoniazid and streptomycin, but not rifampicin. This phenotypic drug tolerance is lost after passage in drug-free media. Transcriptional profiling reveals induction of cell surface regulators, sigE and BCG_0559c alongside the ESX-5 secretion apparatus in these low-shear liquid-suspension biofilms. This study engineers and characterises mycobacteria grown as a suspended biofilm, illuminating new drug discovery pathways for this deadly disease.
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Affiliation(s)
- Daire Cantillon
- grid.12082.390000 0004 1936 7590Global Health and Infection, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX UK
| | - Justyna Wroblewska
- grid.12082.390000 0004 1936 7590Global Health and Infection, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX UK
| | - Ian Cooper
- grid.12477.370000000121073784School of Pharmacy & Biomolecular Sciences, University of Brighton, Brighton, BN2 4GJ UK
| | - Melanie J. Newport
- grid.12082.390000 0004 1936 7590Global Health and Infection, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX UK
| | - Simon J. Waddell
- grid.12082.390000 0004 1936 7590Global Health and Infection, Brighton and Sussex Medical School, University of Sussex, Brighton, BN1 9PX UK
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