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Singhal L, Sandhu D, Gupta V, Kour I. Salmonella Typhi: A Review of Antibiogram Journey in Developing Countries. Infect Disord Drug Targets 2024; 24:e230124225976. [PMID: 38265374 DOI: 10.2174/0118715265255339240102110929] [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: 06/13/2023] [Revised: 11/20/2023] [Accepted: 11/27/2023] [Indexed: 01/25/2024]
Abstract
BACKGROUND Typhoid fever poses a significant health challenge in low- and middleincome countries (LMiCs), impacting millions of individuals across various age groups. Its prevalence is particularly pronounced in South Asia. Factors contributing to its transmission in South Asia include rapid unplanned urbanization, urban-rural disparities, provision of poor water and sanitation facilities, and open defecation. The mortality rate of typhoid fever is up to 1%, and those who survive have a protracted period of poor health and carry an enormous financial burden. The treatment is further complicated by the emerging antibiotic resistance leaving few treatment options in hands. This issue has become more urgent due to the further emergence of extended drug-resistant (XDR) and multidrug-resistant (MDR) typhoid strains, as well as their subsequent global spread. Fluoroquinolone-resistant Salmonella spp. is currently classified by the World Health Organization (WHO) as a high (Priority 2) pathogen. As a result, establishing minimum inhibitory concentrations (MIC) according to the latest guidelines may prove effective in treating typhoid fever and minimizing the rising threat of drug resistance.
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Affiliation(s)
- Lipika Singhal
- Department of Microbiology, Government Medical College & Hospital, Chandigarh, 160030, India
| | - Diljot Sandhu
- Department of Microbiology, Government Medical College & Hospital, Chandigarh, 160030, India
| | - Varsha Gupta
- Department of Microbiology, Government Medical College & Hospital, Chandigarh, 160030, India
| | - Ivneet Kour
- Department of Microbiology, Government Medical College & Hospital, Chandigarh, 160030, India
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Hajra D, Nair AV, Chakravortty D. Decoding the invasive nature of a tropical pathogen of concern: The invasive non-Typhoidal Salmonella strains causing host-restricted extraintestinal infections worldwide. Microbiol Res 2023; 277:127488. [PMID: 37716125 DOI: 10.1016/j.micres.2023.127488] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/01/2023] [Accepted: 09/06/2023] [Indexed: 09/18/2023]
Abstract
Invasive-Non-Typhoidal Salmonella (iNTS) are the major cause of health concern in the low-income, under-developed nations in Africa and Asia that lack proper sanitation facilities. Around 5% of the NTS cases give rise to invasive, extraintestinal diseases leading to focal infections like osteomyelitis, meningitis, osteoarthritis, endocarditis and neonatal sepsis. iNTS serovars like S. Typhimurium, S. Enteritidis, S. Dublin, S. Choleraesuis show a greater propensity to become invasive than others which hints at the genetic basis of their emergence. The major risk factors attributing to the invasive diseases include immune-compromised individuals having co-infection with malaria or HIV, or suffering from malnutrition. The rampant use of antibiotics leading to the emergence of multi-drug resistant strains poses a great challenge in disease management. An extensive understanding of the iNTS pathogenesis and its epidemiology will open up avenues for the development of new vaccination and therapeutic strategies to restrict the spread of this neglected disease.
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Affiliation(s)
- Dipasree Hajra
- Department of Microbiology & Cell Biology, Indian Institute of Science, India
| | - Abhilash Vijay Nair
- Department of Microbiology & Cell Biology, Indian Institute of Science, India
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Igo M, Xu L, Krishna A, Stewart S, Xu L, Li Z, Weaver JL, Stone H, Sacks L, Bensman T, Florian J, Rouse R, Han X. A metagenomic analysis for combination therapy of multiple classes of antibiotics on the prevention of the spread of antibiotic-resistant genes. Gut Microbes 2023; 15:2271150. [PMID: 37908118 PMCID: PMC10621307 DOI: 10.1080/19490976.2023.2271150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 10/11/2023] [Indexed: 11/02/2023] Open
Abstract
Antibiotics used systemically to treat infections may have off-target effects on the gut microbiome, potentially resulting in the emergence of drug-resistant bacteria or selection of pathogenic species. These organisms may present a risk to the host and spread to the environment with a risk of transmission in the community. To investigate the risk of emergent antibiotic resistance in the gut microbiome following systemic treatment with antibiotics, this metagenomic analysis project used next-generation sequencing, a custom-built metagenomics pipeline, and differential abundance analysis to study the effect of antibiotics (ampicillin, ciprofloxacin, and fosfomycin) in monotherapy and different combinations at high and low doses, to determine the effect on resistome and taxonomic composition in the gut of Balb/c mice. The results showed that low-dose monotherapy treatments showed little change in microbiome composition but did show an increase in expression of many antibiotic-resistant genes (ARGs) posttreatment. Dual combination treatments allowed the emergence of some conditionally pathogenic bacteria and some increase in the abundance of ARGs despite a general decrease in microbiota diversity. Triple combination treatment was the most successful in inhibiting emergence of relevant opportunistic pathogens and completely suppressed all ARGs after 72 h of treatment. The relative abundances of mobile genetic elements that can enhance transmission of antibiotic resistance either decreased or remained the same for combination therapy while increasing for low-dose monotherapy. Combination therapy prevented the emergence of ARGs and decreased bacterial diversity, while low-dose monotherapy treatment increased ARGs and did not greatly change bacterial diversity.
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Affiliation(s)
- Matthew Igo
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Lei Xu
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Ashok Krishna
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Sharron Stewart
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Lin Xu
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Zhihua Li
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - James L. Weaver
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Heather Stone
- Office of Medical Policy, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Leonard Sacks
- Office of Medical Policy, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Timothy Bensman
- Division of Infectious Disease Pharmacology, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Jeffry Florian
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Rodney Rouse
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
| | - Xiaomei Han
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD, USA
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Athar M, Gervasoni S, Catte A, Basciu A, Malloci G, Ruggerone P, Vargiu AV. Tripartite efflux pumps of the RND superfamily: what did we learn from computational studies? MICROBIOLOGY (READING, ENGLAND) 2023; 169. [PMID: 36972322 DOI: 10.1099/mic.0.001307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Bacterial resistance to antibiotics has been long recognized as a priority to address for human health. Among all micro-organisms, the so-called multi-drug resistant (MDR) bacteria, which are resistant to most, if not all drugs in our current arsenal, are particularly worrisome. The World Health Organization has prioritized the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species) pathogens, which include four Gram-negative bacterial species. In these bacteria, active extrusion of antimicrobial compounds out of the cell by means of 'molecular guns' known as efflux pumps is a main determinant of MDR phenotypes. The resistance-nodulation-cell division (RND) superfamily of efflux pumps connecting the inner and outer membrane in Gram-negative bacteria is crucial to the onset of MDR and virulence, as well as biofilm formation. Thus, understanding the molecular basis of the interaction of antibiotics and inhibitors with these pumps is key to the design of more effective therapeutics. With the aim to contribute to this challenge, and complement and inspire experimental research, in silico studies on RND efflux pumps have flourished in recent decades. Here, we review a selection of such investigations addressing the main determinants behind the polyspecificity of these pumps, the mechanisms of substrate recognition, transport and inhibition, as well as the relevance of their assembly for proper functioning, and the role of protein-lipid interactions. The journey will end with a perspective on the role of computer simulations in addressing the challenges posed by these beautifully complex machineries and in supporting the fight against the spread of MDR bacteria.
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Affiliation(s)
- Mohd Athar
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Silvia Gervasoni
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Andrea Catte
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Andrea Basciu
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Giuliano Malloci
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Paolo Ruggerone
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
| | - Attilio Vittorio Vargiu
- Physics Department, University of Cagliari, Cittadella Universitaria, SP 8 km 0.700, 09042, Monserrato (CA), Italy
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Chaudhari R, Singh K, Kodgire P. Biochemical and molecular mechanisms of antibiotic resistance in Salmonella spp. Res Microbiol 2023; 174:103985. [PMID: 35944794 DOI: 10.1016/j.resmic.2022.103985] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 01/11/2023]
Abstract
Salmonella is a diverse Gram-negative bacterium that represents the major disease burden worldwide. According to WHO, Salmonella is one of the fourth global causes of diarrhoeal disease. Antibiotic resistance is a worldwide health concern, and Salmonella spp. is one of the microorganisms that can evade the toxicity of antimicrobials via antibiotic resistance. This review aims to deliver in-depth knowledge of the molecular mechanisms and the underlying biochemical alterations perceived in antibiotic resistance in Salmonella. This information will help understand and mitigate the impact of antibiotic-resistant bacteria on humans and contribute to the state-of-the-art research developing newer and more potent antibiotics.
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Affiliation(s)
- Rahul Chaudhari
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore 453552, India
| | - Kanika Singh
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore 453552, India
| | - Prashant Kodgire
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology, Indore, Simrol, Khandwa Road, Indore 453552, India.
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Ul Haq S, Wang L, Guo W, Aqib AI, Muneer A, Saqib M, Ahmad S, Ghafoor M, Iftikhar A, Chen K, Liang J. Enhancing activity of β-lactam and fluoroquinolones antibiotics by artemisinin and its derivatives against MDR Escherichia coli. Front Vet Sci 2022; 9:1048531. [PMID: 36439355 PMCID: PMC9686389 DOI: 10.3389/fvets.2022.1048531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 10/11/2022] [Indexed: 11/11/2022] Open
Abstract
Artemisinin and its derivatives had played a biocidal role in biomedical remedies, while they were expected to enhance the activity of antibiotics against multiple drug-resistant (MDR) bacteria. The current study evaluated the interaction of artemisinin (ART), dihydroartemisinin (DHA), artesunate (AS), and artemisinic acid (AA) with β-lactam and fluoroquinolones antibiotics against Escherichia coli. Antibiotic strip test (E-test), Kirby Bauer's disc test (KB method), and broth microdilution method were adopted for susceptibility analysis, while the checkerboard method was applied to assess synergisms. ART, DHA, AS, and AA showed significantly enhanced antibacterial effects of β-lactam antibiotics against different strains of E. coli. The study showed ciprofloxacin to be most effective by presenting the least MIC (0.017125 ± 0.0022 μg/ml), while oxacillin was least effective (MIC 256 μg/ml) against E. coli. Synergism between AA and penicillin G (75%), ampicillin (25%), and oxacillin (50%) was observed in all isolates tested. AA and AS significantly decreased the MIC of ampicillin (-0.912 ± 0.908 μg/ml) and ciprofloxacin (-0.901 ± 0.893 g/ml), respectively. Artemisinin and its derivatives increased antibiotic accumulation within E. coli in a dose-dependent manner. The time-kill assay significantly reduced the bacterial number within 24 h of incubation. The study thus concludes greater room for improvement in enhancing the efficacy of antibiotics if used with artemisinin and its derivatives.
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Affiliation(s)
- Shahbaz Ul Haq
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou, China
| | - Ling Wang
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou, China
| | - Wenzhou Guo
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou, China
| | - Amjad Islam Aqib
- Department of Medicine, Cholistan University of Veterinary and Animal Sciences, Bahawalpur, Pakistan
| | - Afshan Muneer
- Department of Zoology, Cholistan University of Veterinary and Animal Sciences, Bahawalpur, Pakistan
| | - Muhammad Saqib
- Department of Clinical Medicine and Surgery, University of Agriculture, Faisalabad, Pakistan
| | - Saad Ahmad
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou, China
| | - Muzafar Ghafoor
- Department of Clinical Medicine and Surgery, University of Agriculture, Faisalabad, Pakistan
| | - Amir Iftikhar
- Department of Clinical Medicine and Surgery, Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Keyuan Chen
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou, China
| | - Jianping Liang
- Key Laboratory of New Animal Drug Project, Gansu Province, Key Laboratory of Veterinary Pharmaceutical Development, Ministry of Agriculture and Rural Affairs, Lanzhou Institute of Husbandry and Pharmaceutical Sciences of Chinese Academy of Agriculture Sciences, Lanzhou, China
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Miranda CD, Concha C, Godoy FA, Lee MR. Aquatic Environments as Hotspots of Transferable Low-Level Quinolone Resistance and Their Potential Contribution to High-Level Quinolone Resistance. Antibiotics (Basel) 2022; 11:1487. [PMID: 36358142 PMCID: PMC9687057 DOI: 10.3390/antibiotics11111487] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 10/01/2022] [Accepted: 10/04/2022] [Indexed: 08/27/2023] Open
Abstract
The disposal of antibiotics in the aquatic environment favors the selection of bacteria exhibiting antibiotic resistance mechanisms. Quinolones are bactericidal antimicrobials extensively used in both human and animal medicine. Some of the quinolone-resistance mechanisms are encoded by different bacterial genes, whereas others are the result of mutations in the enzymes on which those antibiotics act. The worldwide occurrence of quinolone resistance genes in aquatic environments has been widely reported, particularly in areas impacted by urban discharges. The most commonly reported quinolone resistance gene, qnr, encodes for the Qnr proteins that protect DNA gyrase and topoisomerase IV from quinolone activity. It is important to note that low-level resistance usually constitutes the first step in the development of high-level resistance, because bacteria carrying these genes have an adaptive advantage compared to the highly susceptible bacterial population in environments with low concentrations of this antimicrobial group. In addition, these genes can act additively with chromosomal mutations in the sequences of the target proteins of quinolones leading to high-level quinolone resistance. The occurrence of qnr genes in aquatic environments is most probably caused by the release of bacteria carrying these genes through anthropogenic pollution and maintained by the selective activity of antimicrobial residues discharged into these environments. This increase in the levels of quinolone resistance has consequences both in clinical settings and the wider aquatic environment, where there is an increased exposure risk to the general population, representing a significant threat to the efficacy of quinolone-based human and animal therapies. In this review the potential role of aquatic environments as reservoirs of the qnr genes, their activity in reducing the susceptibility to various quinolones, and the possible ways these genes contribute to the acquisition and spread of high-level resistance to quinolones will be discussed.
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Affiliation(s)
- Claudio D. Miranda
- Laboratorio de Patobiología Acuática, Departamento de Acuicultura, Universidad Católica del Norte, Coquimbo 1780000, Chile
| | - Christopher Concha
- Laboratorio de Patobiología Acuática, Departamento de Acuicultura, Universidad Católica del Norte, Coquimbo 1780000, Chile
| | - Félix A. Godoy
- Centro i~mar, Universidad de Los Lagos, Puerto Montt 5480000, Chile
| | - Matthew R. Lee
- Centro i~mar, Universidad de Los Lagos, Puerto Montt 5480000, Chile
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Droplet Digital PCR-Based Detection and Quantification of GyrA Thr-86-Ile Mutation Based Fluoroquinolone-Resistant Campylobacter jejuni. Microbiol Spectr 2022; 10:e0276921. [PMID: 35412390 PMCID: PMC9045142 DOI: 10.1128/spectrum.02769-21] [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] [Indexed: 11/20/2022] Open
Abstract
Fluoroquinolone (FQ)-resistant Campylobacter jejuni is a serious problem worldwide that limits effective treatment of infections. The traditional detection method depends on bacterial isolation and MIC testing, or traditional PCR, which is time-consuming and hard to identify the FQ-resistant C. jejuni in a high abundance wild-type background. This study aimed to develop a rapid and accurate ddPCR assay to detect FQ-resistant C. jejuni mutants based on the crucial resistance mutation C257T (Thr-86-Ile) in gyrA. Our ddPCR gyrA assay showed high specificity and accuracy. Sanger sequencing and the qPCR assay could only recognize gyrA mutant sequences when the ratios of wild-type/mutant were 1:1 or 10:1, respectively. Our ddPCR gyrA assay was able to detect gyrA mutant sequences in the mixtures with up to at least 1000:1 wild-type/mutant ratios, which suggested a significant advantage to distinguish the low mutant signal from the wild-type background. We further monitored the occurrence of gyrA mutations under ciprofloxacin pressure using our ddPCR gyrA assay, and clearly showed that the transition of a dominant C. jejuni subpopulation from wild-type to gyrA C257T mutant, resulting in FQ-resistance. We tested 52 samples from live chickens and retail chicken meat and showed that four samples contained wild-type/mutant mixtures comprising 1.7%, 28.6%, 53.3%, and 87.0% gyrA C257T mutants, respectively. These results demonstrated that the ddPCR gyrA assay was a highly sensitive alternative method to distinguish and quantify FQ-resistant C. jejuni infections that could help guide the appropriate use of FQs in clinical practice. IMPORTANCECampylobacter jejuni is considered to be the leading cause of human bacterial gastroenteritis worldwide, and fluoroquinolones (FQs) are the main choices for the treatment of bacterial gastroenteritis in clinical practice. In theory, antimicrobial susceptibility testing should help us to choose the most appropriate drugs for the treatment. However, to test the susceptibility of C. jejuni to FQs, the standardized method is bacteria isolation and MIC measurement, which will take more than 4 days. In addition, a low abundance of FQ-resistant C. jejuni is also hardly distinguished from a high abundance of wild-type background in the mixed infection. Therefore, the development of rapid and accurate detection technology for FQ-resistant C. jejuni is very important. This study provided a ddPCR gyrA assay, which is a highly sensitive alternative method to distinguish and quantify FQ-resistant C. jejuni infections that may help guide the appropriate use of FQs both in veterinary and human clinical practice.
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Youlden G, McNeil HE, Blair JMA, Jabbari S, King JR. Mathematical Modelling Highlights the Potential for Genetic Manipulation as an Adjuvant to Counter Efflux-Mediated MDR in Salmonella. Bull Math Biol 2022; 84:56. [PMID: 35380320 PMCID: PMC8983579 DOI: 10.1007/s11538-022-01011-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 03/02/2022] [Indexed: 11/18/2022]
Abstract
Bacteria have developed resistance to antibiotics by various mechanisms, notable amongst these is the use of permeation barriers and the expulsion of antibiotics via efflux pumps. The resistance-nodulation-division (RND) family of efflux pumps is found in Gram-negative bacteria and a major contributor to multidrug resistance (MDR). In particular, Salmonella encodes five RND efflux pump systems: AcrAB, AcrAD, AcrEF, MdsAB and MdtAB which have different substrate ranges including many antibiotics. We produce a spatial partial differential equation (PDE) model governing the diffusion and efflux of antibiotic in Salmonella, via these RND efflux pumps. Using parameter fitting techniques on experimental data, we are able to establish the behaviour of multiple wild-type and efflux mutant Salmonella strains, which enables us to produce efflux profiles for each individual efflux pump system. By combining the model with a gene regulatory network (GRN) model of efflux regulation, we simulate how the bacteria respond to their environment. Finally, performing a parameter sensitivity analysis, we look into various different targets to inhibit the efflux pumps. The model provides an in silico framework with which to test these potential adjuvants to counter MDR.
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Affiliation(s)
- George Youlden
- School of Mathematics, University of Birmingham, Birmingham, B15 2TT, UK.
- School of Mathematical Sciences, University of Nottingham, Nottingham, NG7 2RD, UK.
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, B15 2TT, UK.
| | - Helen E McNeil
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, B15 2TT, UK
| | - Jessica M A Blair
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, B15 2TT, UK
| | - Sara Jabbari
- School of Mathematics, University of Birmingham, Birmingham, B15 2TT, UK
- Institute of Microbiology and Infection, University of Birmingham, Birmingham, B15 2TT, UK
| | - John R King
- School of Mathematical Sciences, University of Nottingham, Nottingham, NG7 2RD, UK
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Pang X, Wu Y, Liu X, Wu Y, Shu Q, Niu J, Chen Q, Zhang X. The Lipoteichoic Acid-Related Proteins YqgS and LafA Contribute to the Resistance of Listeria monocytogenes to Nisin. Microbiol Spectr 2022; 10:e0209521. [PMID: 35196823 PMCID: PMC8865564 DOI: 10.1128/spectrum.02095-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/24/2022] [Indexed: 11/20/2022] Open
Abstract
Listeria monocytogenes is a major pathogen contributing to foodborne outbreaks with high mortality. Nisin, a natural antimicrobial, has been widely used as a food preservative. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. A mariner transposon library was constructed in L. monocytogenes, leading to the identification of 99 genes associated with the innate resistance to nisin via Transposon sequencing (Tn-seq) analysis. To validate the accuracy of the Tn-seq results, we constructed five mutants (ΔyqgS, ΔlafA, ΔvirR, ΔgtcA, and Δlmo1464) in L. monocytogenes. The results revealed that yqgS and lafA, the lipoteichoic acid-related genes, were essential for resistance to nisin, while the gtcA and lmo1464 mutants showed substantially enhanced nisin resistance. Densely wrinkled, collapsed surface and membrane breakdown were shown on ΔyqgS and ΔlafA mutants under nisin treatment. Deletion of yqgS and lafA altered the surface charge, and decreased the resistance to general stress conditions and cell envelope-acting antimicrobials. Furthermore, YqgS and LafA are required for biofilm formation and cell invasion of L. monocytogenes. Collectively, these results reveal novel mechanisms of nisin resistance in L. monocytogenes and may provide unique targets for the development of food-grade inhibitors for nisin-resistant foodborne pathogens. IMPORTANCE Listeria monocytogenes is an opportunistic Gram-positive pathogen responsible for listeriosis, and is widely present in a variety of foods including ready-to-eat foods, meat, and dairy products. Nisin is the only licensed lantibiotic by the FDA for use as a food-grade inhibitor in over 50 countries. A prior study suggests that L. monocytogenes are more resistant than other Gram-positive pathogens in nisin-mediated bactericidal effects. However, the mechanisms of L. monocytogenes involved in nisin resistance have not yet to be fully defined. Here, we used a mariner transposon library to identify nisin-resistance-related genes on a genome-wide scale via transposon sequencing. We found, for the first time, that YqgS and LafA (Lipoteichoic acid-related proteins) are required for resistance to nisin. Subsequently, we investigated the roles of YqgS and LafA in L. monocytogenes stress resistance, antimicrobial resistance, biofilm formation, and virulence in mammalian cells.
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Affiliation(s)
- Xinxin Pang
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
| | - Yansha Wu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
| | - Xiayu Liu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
| | - Yajing Wu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
| | - Qin Shu
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
| | - Jianrui Niu
- College of Agriculture and Forestry, Linyi University, Linyi, China
| | - Qihe Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
| | - Xinglin Zhang
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China
- College of Agriculture and Forestry, Linyi University, Linyi, China
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11
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Cacciotto P, Basciu A, Oliva F, Malloci G, Zacharias M, Ruggerone P, Vargiu AV. Molecular rationale for the impairment of the MexAB-OprM efflux pump by a single mutation in MexA. Comput Struct Biotechnol J 2022; 20:252-260. [PMID: 35024097 PMCID: PMC8717590 DOI: 10.1016/j.csbj.2021.11.042] [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: 09/02/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 11/16/2022] Open
Abstract
Efflux pumps of the Resistance-Nodulation-cell Division (RND) superfamily contribute to intrinsic and acquired resistance in Gram-negative pathogens by expelling chemically unrelated antibiotics with high efficiency. They are tripartite systems constituted by an inner-membrane-anchored transporter, an outer membrane factor protein, and a membrane fusion protein. Multimerization of the membrane fusion protein is an essential prerequisite for full functionality of these efflux pumps. In this work, we employed complementary computational techniques to investigate the stability of a dimeric unit of MexA (the membrane fusion protein of the MexAB-OprM RND efflux pump of Pseudomonas aeruginosa), and to provide a molecular rationale for the effect of the G72S substitution, which affects MexAB-OprM functionality by impairing the assembly of MexA. Our findings indicate that: i) dimers of this protein are stable in multiple µs-long molecular dynamics simulations; ii) the mutation drastically alters the conformational equilibrium of MexA, favouring a collapsed conformation that is unlikely to form dimers or higher order assemblies. Unveiling the mechanistic aspects underlying large conformational distortions induced by minor sequence changes is informative to efforts at interfering with the activity of this elusive bacterial weapon. In this respect, our work further confirms how molecular simulations can give important contribution and useful insights to characterize the mechanism of highly complex biological systems.
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Affiliation(s)
- Pierpaolo Cacciotto
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Andrea Basciu
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Francesco Oliva
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Giuliano Malloci
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Martin Zacharias
- Physics Department, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany
| | - Paolo Ruggerone
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
| | - Attilio V Vargiu
- Dipartimento di Fisica, Università degli Studi di Cagliari, S.P. Monserrato-Sestu km 0.700, I-09042 Monserrato (CA), Italy
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12
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Azargun R, Gholizadeh P, Sadeghi V, Hosainzadegan H, Tarhriz V, Memar MY, Pormohammad A, Eyvazi S. Molecular mechanisms associated with quinolone resistance in Enterobacteriaceae: review and update. Trans R Soc Trop Med Hyg 2021; 114:770-781. [PMID: 32609840 DOI: 10.1093/trstmh/traa041] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 04/09/2020] [Accepted: 05/20/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Quinolones are broad-spectrum antibiotics, which are used for the treatment of different infectious diseases associated with Enterobacteriaceae. During recent decades, the wide use as well as overuse of quinolones against diverse infections has led to the emergence of quinolone-resistant bacterial strains. Herein, we present the development of quinolone antibiotics, their function and also the different quinolone resistance mechanisms in Enterobacteriaceae by reviewing recent literature. METHODS All data were extracted from Google Scholar search engine and PubMed site, using keywords; quinolone resistance, Enterobacteriaceae, plasmid-mediated quinolone resistance, etc. RESULTS AND CONCLUSION The acquisition of resistance to quinolones is a complex and multifactorial process. The main resistance mechanisms consist of one or a combination of target-site gene mutations altering the drug-binding affinity of target enzymes. Other mechanisms of quinolone resistance are overexpression of AcrAB-tolC multidrug-resistant efflux pumps and downexpression of porins as well as plasmid-encoded resistance proteins including Qnr protection proteins, aminoglycoside acetyltransferase (AAC(6')-Ib-cr) and plasmid-encoded active efflux pumps such as OqxAB and QepA. The elucidation of resistance mechanisms will help researchers to explore new drugs against the resistant strains.
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Affiliation(s)
- Robab Azargun
- Department of Microbiology, Faculty of Medicine, Maragheh University of Medical Sciences, Maragheh, Iran
| | - Pourya Gholizadeh
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Vahid Sadeghi
- Faculty of Veterinary Medicine, Islamic Azad University, Urmia, Iran
| | - Hasan Hosainzadegan
- Department of Microbiology, Faculty of Medicine, Maragheh University of Medical Sciences, Maragheh, Iran
| | - Vahideh Tarhriz
- Molecular Medicine Research Center, Biomedicine Institute, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Yousef Memar
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Pormohammad
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shirin Eyvazi
- Department of Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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13
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Chang MX, Zhang JF, Sun YH, Li RS, Lin XL, Yang L, Webber MA, Jiang HX. Contribution of Different Mechanisms to Ciprofloxacin Resistance in Salmonella spp. Front Microbiol 2021; 12:663731. [PMID: 34025618 PMCID: PMC8137344 DOI: 10.3389/fmicb.2021.663731] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 04/09/2021] [Indexed: 11/28/2022] Open
Abstract
Development of fluoroquinolone resistance can involve several mechanisms that include chromosomal mutations in genes (gyrAB and parCE) encoding the target bacterial topoisomerase enzymes, increased expression of the AcrAB-TolC efflux system, and acquisition of transmissible quinolone-resistance genes. In this study, 176 Salmonella isolates from animals with a broad range of ciprofloxacin MICs were collected to analyze the contribution of these different mechanisms to different phenotypes. All isolates were classified according to their ciprofloxacin susceptibility pattern into five groups as follows: highly resistant (HR), resistant (R), intermediate (I), reduced susceptibility (RS), and susceptible (S). We found that the ParC T57S substitution was common in strains exhibiting lowest MICs of ciprofloxacin while increased MICs depended on the type of GyrA mutation. The ParC T57S substitution appeared to incur little cost to bacterial fitness on its own. The presence of PMQR genes represented an route for resistance development in the absence of target-site mutations. Switching of the plasmid-mediated quinolone resistance (PMQR) gene location from a plasmid to the chromosome was observed and resulted in decreased ciprofloxacin susceptibility; this also correlated with increased fitness and a stable resistance phenotype. The overexpression of AcrAB-TolC played an important role in isolates with small decreases in susceptibility and expression was upregulated by MarA more often than by RamA. This study increases our understanding of the relative importance of several resistance mechanisms in the development of fluoroquinolone resistance in Salmonella from the food chain.
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Affiliation(s)
- Man-Xia Chang
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Jin-Fei Zhang
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yin-Huan Sun
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Rong-Sheng Li
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Xiao-Ling Lin
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Ling Yang
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Mark A Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, United Kingdom.,Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, United Kingdom
| | - Hong-Xia Jiang
- Guangdong Key Laboratory of Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
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14
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Kaur UJ, Chopra A, Preet S, Raj K, Kondepudi KK, Gupta V, Rishi P. Potential of 1-(1-napthylmethyl)-piperazine, an efflux pump inhibitor against cadmium-induced multidrug resistance in Salmonella enterica serovar Typhi as an adjunct to antibiotics. Braz J Microbiol 2021; 52:1303-1313. [PMID: 33851343 DOI: 10.1007/s42770-021-00492-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 04/06/2021] [Indexed: 01/30/2023] Open
Abstract
This study was focused on elucidating inhibition of antibiotic efflux mechanism of cadmium adapted (CdA) Salmonella Typhi Ty2 cells. Herein, upregulated expression of efflux genes (acrB, tolC) and their regulators (soxS, marA) was observed in CdA Ty2 cells by qRT-PCR. The pathogen further elevated the expression of these genes even in the presence of three efflux pump inhibitors (EPIs), i.e., Phe-Arg-β-naphthylamide, 1-(1-naphthyl-methyl)piperazine, and 5-hydroxy-2-methyl-1,4-naphthoquinone, perhaps by sensing the pressure of the latter in addition to cadmium stress. Interaction of different EPIs with efflux pumps of CdA Ty2 cells was confirmed using ethidium bromide (EtBr) accumulation and efflux assay. All the EPIs could cause retention of EtBr which was indicated by increased fluorescence units. Considering this potential of EPIs, retention of antibiotics was evaluated in CdA Ty2 cells wherein EPIs were used in combination with selected antibiotics (instead of EtBr). A decrease in the effective concentration of antibiotics was observed. This was further validated using the clinical isolates. The data revealed the efficiency of EPIs as they could inhibit the efflux potential of even the overexpressed efflux pumps. Thus, combination of EPI(s)-antibiotics may be exploited in future as one of the strategies for combating metal induced antibiotic resistance.
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Affiliation(s)
- Ujjwal Jit Kaur
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Adity Chopra
- Department of Microbiology, Panjab University, Chandigarh, India
| | - Simran Preet
- Department of Biophysics, Panjab University, Chandigarh, India
| | - Khem Raj
- Department of Microbiology, Panjab University, Chandigarh, India
| | | | - Varsha Gupta
- Government Medical College and Hospital, Sector- 32, Chandigarh, India
| | - Praveen Rishi
- Department of Microbiology, Panjab University, Chandigarh, India.
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15
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Azargun R, Sadeghi V, Leylabadlo HE, Alizadeh N, Ghotaslou R. Molecular mechanisms of fluoroquinolone resistance in Enterobacteriaceae clinical isolates in Azerbaijan, Iran. GENE REPORTS 2020. [DOI: 10.1016/j.genrep.2020.100924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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16
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Lu WJ, Lin HJ, Hsu PH, Lin HTV. Determination of Drug Efflux Pump Efficiency in Drug-Resistant Bacteria Using MALDI-TOF MS. Antibiotics (Basel) 2020; 9:antibiotics9100639. [PMID: 32987695 PMCID: PMC7598683 DOI: 10.3390/antibiotics9100639] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/18/2020] [Accepted: 09/22/2020] [Indexed: 12/26/2022] Open
Abstract
Multidrug efflux pumps play an essential role in antibiotic resistance. The conventional methods, including minimum inhibitory concentration and fluorescent assays, to monitor transporter efflux activity might have some drawbacks, such as indirect evidence or interference from color molecules. In this study, MALDI-TOF MS use was explored for monitoring drug efflux by a multidrug transporter, and the results were compared for validation with the data from conventional methods. Minimum inhibitory concentration was used first to evaluate the activity of Escherichia coli drug transporter AcrB, and this analysis showed that the E. coli overexpressing AcrB exhibited elevated resistance to various antibiotics and dyes. Fluorescence-based studies indicated that AcrB in E. coli could decrease the accumulation of intracellular dyes and display various efflux rate constants for different dyes, suggesting AcrB’s efflux activity. The MALDI-TOF MS analysis parameters were optimized to maintain a detection accuracy for AcrB’s substrates; furthermore, the MS data showed that E. coli overexpressing AcrB led to increased ions abundancy of various dyes and drugs in the extracellular space at different rates over time, illustrating continuous substrate efflux by AcrB. This study concluded that MALDI-TOF MS is a reliable method that can rapidly determine the drug pump efflux activity for various substrates.
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Affiliation(s)
- Wen-Jung Lu
- Department of Food Science, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202, Taiwan; (W.-J.L.); (H.-J.L.)
| | - Hsuan-Ju Lin
- Department of Food Science, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202, Taiwan; (W.-J.L.); (H.-J.L.)
| | - Pang-Hung Hsu
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202, Taiwan
- Center of Excellence for the Oceans, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202, Taiwan
- Institute of Biochemistry and Molecular Biology, National Yang Ming University, No. 155, Sec. 2, Linong Street, Taipei 112, Taiwan
- Correspondence: (P.-H.H.); (H.-T.V.L.); Tel.: +886-2-2462-2192 (ext. 5567) (P.-H.H.); +886-2-2462-2192 (ext. 5121) (H.-T.V.L.); Fax: +886-2-2463-4203 (H.-T.V.L.)
| | - Hong-Ting Victor Lin
- Department of Food Science, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202, Taiwan; (W.-J.L.); (H.-J.L.)
- Center of Excellence for the Oceans, National Taiwan Ocean University, No. 2, Pei-Ning Road, Keelung 202, Taiwan
- Correspondence: (P.-H.H.); (H.-T.V.L.); Tel.: +886-2-2462-2192 (ext. 5567) (P.-H.H.); +886-2-2462-2192 (ext. 5121) (H.-T.V.L.); Fax: +886-2-2463-4203 (H.-T.V.L.)
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17
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Wei S, Yang Y, Tian W, Liu M, Yin S, Li J. Synergistic Activity of Fluoroquinolones Combining with Artesunate Against Multidrug-Resistant Escherichia coli. Microb Drug Resist 2019; 26:81-88. [PMID: 31738637 PMCID: PMC6978754 DOI: 10.1089/mdr.2018.0463] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Multidrug resistance (MDR) is an increasing public health concern worldwide. Artesunate (ART) has been reported to be significantly effective in enhancing the effectiveness of various β-lactam antibiotics against MDR Escherichia coli via inhibiting the efflux pump genes. Apart from β-lactam antibiotics, there is no report regarding the potential synergistic effects of ART combining with fluoroquinolones (FQs). In this study, we investigated whether ART can enhance the antibacterial effects of FQs in vitro. The antibacterial activity of ART and antibiotics against 13 animal-derived E. coli clinical isolates was assessed for screening MDR strains. Then the synergistic activity of FQs with ART against MDR E. coli isolates was evaluated. Daunorubicin (DNR) accumulation within E. coli and messenger RNA (mRNA) expressions of acrA, acrB, tolC, and qnr genes were investigated. The results showed that ART did not show significant antimicrobial activity. However, a dramatically synergistic activity of ART combining with FQs was obsessed with (ΣFIC) = 0.12-0.33. ART increased the DNR accumulation and reduced acrAB-tolC mRNA expression, but enhanced the mRNA expression of qnrS and qnrB within MDR E. coli isolates. These findings suggest that ART can potentiate FQs activity which may be associated with drug accumulation by inhibiting the expression of acrAB-tolC.
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Affiliation(s)
- SiMin Wei
- Department of Clinical Veterinary Medicine, School of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
| | - YueFei Yang
- Department of Clinical Veterinary Medicine, School of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
| | - Wei Tian
- Department of Clinical Veterinary Medicine, School of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
| | - MingJiang Liu
- Department of Clinical Veterinary Medicine, School of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
| | - ShaoJie Yin
- Department of Clinical Veterinary Medicine, School of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
| | - JinGui Li
- Department of Clinical Veterinary Medicine, School of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, P.R. China
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18
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Hashemi SJ, Sheikh AF, Goodarzi H, Yadyad MJ, Seyedian SS, Aslani S, Assarzadegan MA. Genetic basis for metronidazole and clarithromycin resistance in Helicobacter pylori strains isolated from patients with gastroduodenal disorders. Infect Drug Resist 2019; 12:535-543. [PMID: 30881059 PMCID: PMC6404679 DOI: 10.2147/idr.s192942] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The aim of this study was to evaluate the antimicrobial resistance and genetic basis for metronidazole (Mtz) and clarithromycin (Cla) resistance in strains of Helicobacter pylori, isolated from patients with gastroduodenal disorders. PATIENTS AND METHODS A total of 157 H. pylori isolates (from 22 gastric cancer, 38 peptic ulcer disease, and 97 non-ulcer dyspepsia patients) were analyzed for drug susceptibility to Mtz and Cla, by gradient diffusion test (E-test, MAST). The PCR and sequence analysis of the rdxA and frxA for Mtz-resistant strains and the 23S rRNA for Cla-resistant strains were used to determine the genetic basis of drug resistance in H. pylori strains. Increased expression of TolC homologous genes (hefA) that upregulates efflux pump activity was determined in multidrug-resistant (MDR) strain of H. pylori by real-time PCR technique. RESULTS Among 157 H. pylori isolates, 32 (20.4%) strains were resistant to at least one of the antimicrobial agents. The highest resistance rate was attributed to Mtz (n=69, 43.94%). Among the resistant strains of H. pylori, 15 cases (9.55%) were detected as MDR. Mutations in the rdxA (85.5%) and A2143G point mutations (63.1%) in the 23S rRNA were the most common cause of resistance to Mtz and Cla in strains of H. pylori, respectively. In MDR strains, the rdxA mutation and A2143G-point mutation in the 23S rRNA were the most abundant mutations responsible for drug resistance. The relative expression of hefA in MDR strains (mean 3.706) was higher than the susceptible strains (mean 1.07). CONCLUSION Mutational inactivation and efflux pump overexpression are two mechanisms that increase the resistance to H. pylori antimicrobial agents and the rate of MDR strains. In Iran, the mutations of rdxA and frxA in Mtz-resistant strains and A2143G and A2142G of the 23S rRNA in Cla-resistant strains were significant. The screening for these mutations could help to prevent antibiotic resistance, and to determine the most effective anti-H. pylori drugs.
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Affiliation(s)
- Seyed Jalal Hashemi
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
- Research Institute for Infectious Diseases of the Digestive System, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Division of Gastroenterology and Hepatology, Ahvaz Jundishapur University of Medical Sciences, Ahwaz, Iran
| | - Ahmad Farajzadeh Sheikh
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
| | - Hamed Goodarzi
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
- Molecular Biology Research Center, Baqiyatallah University of Medical Science, Tehran, Iran,
| | - Mohammad Jaafar Yadyad
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran,
| | - Seyed Saeid Seyedian
- Alimentary Tract Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Sajad Aslani
- Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran
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19
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Abstract
During the past decades resistance to virtually all antimicrobial agents has been observed in bacteria of animal origin. This chapter describes in detail the mechanisms so far encountered for the various classes of antimicrobial agents. The main mechanisms include enzymatic inactivation by either disintegration or chemical modification of antimicrobial agents, reduced intracellular accumulation by either decreased influx or increased efflux of antimicrobial agents, and modifications at the cellular target sites (i.e., mutational changes, chemical modification, protection, or even replacement of the target sites). Often several mechanisms interact to enhance bacterial resistance to antimicrobial agents. This is a completely revised version of the corresponding chapter in the book Antimicrobial Resistance in Bacteria of Animal Origin published in 2006. New sections have been added for oxazolidinones, polypeptides, mupirocin, ansamycins, fosfomycin, fusidic acid, and streptomycins, and the chapters for the remaining classes of antimicrobial agents have been completely updated to cover the advances in knowledge gained since 2006.
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20
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V T Nair D, Venkitanarayanan K, Kollanoor Johny A. Antibiotic-Resistant Salmonella in the Food Supply and the Potential Role of Antibiotic Alternatives for Control. Foods 2018; 7:E167. [PMID: 30314348 PMCID: PMC6210005 DOI: 10.3390/foods7100167] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 10/03/2018] [Accepted: 10/03/2018] [Indexed: 01/21/2023] Open
Abstract
Salmonella enterica is one of the most ubiquitous enteropathogenic bacterial species on earth, and comprises more than 2500 serovars. Widely known for causing non-typhoidal foodborne infections (95%), and enteric (typhoid) fever in humans, Salmonella colonizes almost all warm- and cold-blooded animals, in addition to its extra-animal environmental strongholds. The last few decades have witnessed the emergence of highly virulent and antibiotic-resistant Salmonella, causing greater morbidity and mortality in humans. The emergence of several Salmonella serotypes resistant to multiple antibiotics in food animals underscores a significant food safety hazard. In this review, we discuss the various antibiotic-resistant Salmonella serotypes in food animals and the food supply, factors that contributed to their emergence, their antibiotic resistance mechanisms, the public health implications of their spread through the food supply, and the potential antibiotic alternatives for controlling them.
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Affiliation(s)
- Divek V T Nair
- Department of Animal Science, University of Minnesota, Saint Paul, MN 55108 USA.
| | | | - Anup Kollanoor Johny
- Department of Animal Science, University of Minnesota, Saint Paul, MN 55108 USA.
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21
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Masi M, Dumont E, Vergalli J, Pajovic J, Réfrégiers M, Pagès JM. Fluorescence enlightens RND pump activity and the intrabacterial concentration of antibiotics. Res Microbiol 2018; 169:432-441. [DOI: 10.1016/j.resmic.2017.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 11/22/2017] [Accepted: 11/23/2017] [Indexed: 02/01/2023]
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22
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Kennedy CA, Walsh C, Karczmarczyk M, O'Brien S, Akasheh N, Quirke M, Farrell-Ward S, Buckley T, Fogherty U, Kavanagh K, Parker CT, Sweeney T, Fanning S. Multi-drug resistant Escherichia coli in diarrhoeagenic foals: Pulsotyping, phylotyping, serotyping, antibiotic resistance and virulence profiling. Vet Microbiol 2018; 223:144-152. [PMID: 30173740 DOI: 10.1016/j.vetmic.2018.08.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 08/04/2018] [Accepted: 08/04/2018] [Indexed: 01/20/2023]
Abstract
Extraintestinal pathogenic E. coli (ExPEC) possess the ability to cause extraintestinal infections such as urinary tract infections, neonatal meningitis and sepsis. While information is readily available describing pathogenic E. coli populations in food-producing animals, studies in companion/sports animals such as horses are limited. In addition, many antimicrobial agents used in the treatment of equine infections are also utilised in human medicine, potentially contributing to the spread of antibiotic resistance determinants among pathogenic strains. The aim of this study was to phenotypically and genotypically characterise the multidrug resistance and virulence associated with 83 equine E. coli isolates recovered from foals with diarrhoeal disease. Serotyping was performed by both PCR and sequencing. Antibiotic resistance was assessed by disc diffusion. Phylogenetic groups, virulence genes, antibiotic resistance genes and integrons were determined by PCR. Thirty-nine (46%) of the isolates were classified as ExPEC and hence considered to be potentially pathogenic to humans and animals. Identified serogroups O1, O19a, O40, O101 and O153 are among previously reported human clinical ExPEC isolates. Over a quarter of the E. coli were assigned to pathogenic phylogroups B2 (6%) and D (23%). Class 1 and class 2 integrons were detected in 85% of E. coli, revealing their potential to transfer MDR to other pathogenic and non-pathogenic bacteria. With 65% of potentially pathogenic isolates harbouring one or more TEM, SHV and CTX-M-2 group β-lactamases, in addition to the high levels of resistance to fluoroquinolones observed, our findings signal the need for increased attention to companion/sport animal reservoirs as public health threats.
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Affiliation(s)
- C A Kennedy
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland
| | - C Walsh
- School of Food Science and Environmental Health, DIT, Cathal Brugha Street, Dublin, D01 HV58, Ireland; UCD-Center for Food Safety, School of Public Health, Physiotherapy & Sports Science, University College Dublin, Belfield, Dublin D04 N2E5, Ireland
| | - M Karczmarczyk
- UCD-Center for Food Safety, School of Public Health, Physiotherapy & Sports Science, University College Dublin, Belfield, Dublin D04 N2E5, Ireland
| | - S O'Brien
- UCD-Center for Food Safety, School of Public Health, Physiotherapy & Sports Science, University College Dublin, Belfield, Dublin D04 N2E5, Ireland
| | - N Akasheh
- Medical Directorate, St. James's Hospital, Dublin 8, Ireland
| | - M Quirke
- School of Food Science and Environmental Health, DIT, Cathal Brugha Street, Dublin, D01 HV58, Ireland
| | - S Farrell-Ward
- UCD-Center for Food Safety, School of Public Health, Physiotherapy & Sports Science, University College Dublin, Belfield, Dublin D04 N2E5, Ireland
| | - T Buckley
- Irish Equine Centre, Johnstown, Naas, Co. Kildare, W91 RH93, Ireland
| | - U Fogherty
- Irish Equine Centre, Johnstown, Naas, Co. Kildare, W91 RH93, Ireland
| | - K Kavanagh
- Irish Equine Centre, Johnstown, Naas, Co. Kildare, W91 RH93, Ireland
| | - C T Parker
- Produce Safety and Microbiology Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 800 Buchanan Street, Albany, CA, 94710, USA
| | - T Sweeney
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland
| | - S Fanning
- UCD-Center for Food Safety, School of Public Health, Physiotherapy & Sports Science, University College Dublin, Belfield, Dublin D04 N2E5, Ireland.
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Cacciotto P, Ramaswamy VK, Malloci G, Ruggerone P, Vargiu AV. Molecular Modeling of Multidrug Properties of Resistance Nodulation Division (RND) Transporters. Methods Mol Biol 2018; 1700:179-219. [PMID: 29177832 DOI: 10.1007/978-1-4939-7454-2_11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Efflux pumps of the resistance nodulation division (RND) superfamily are among the major contributors to intrinsic and acquired multidrug resistance in Gram-negative bacteria. Structural information on AcrAB-TolC and MexAB-OprM, major efflux pumps of Escherichia coli and Pseudomonas aeruginosa respectively, boosted intensive research aimed at understanding the molecular mechanisms ruling the active extrusion processes. In particular, several studies were devoted to the understanding of the determinants behind the extraordinary broad specificity of the RND transporters AcrB and MexB. In this chapter, we discuss the ever-growing role computational methods have been playing in deciphering key structural and dynamical features of these transporters and of their interaction with substrates and inhibitors. We further discuss and illustrate examples from our lab of how molecular docking, homology modeling, all-atom molecular dynamics simulations and in silico free energy estimations can all together give precious insights into the processes of recognition and extrusion of substrates, as well as on the possible inhibition strategies.
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Affiliation(s)
- Pierpaolo Cacciotto
- Department of Physics, University of Cagliari, s.p. 8, 09042, Monserrato, CA, Italy
| | - Venkata K Ramaswamy
- Department of Physics, University of Cagliari, s.p. 8, 09042, Monserrato, CA, Italy
| | - Giuliano Malloci
- Department of Physics, University of Cagliari, s.p. 8, 09042, Monserrato, CA, Italy
| | - Paolo Ruggerone
- Department of Physics, University of Cagliari, s.p. 8, 09042, Monserrato, CA, Italy
| | - Attilio V Vargiu
- Department of Physics, University of Cagliari, s.p. 8, 09042, Monserrato, CA, Italy.
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Liao SW, Lee JJ, Ptak CP, Wu YC, Hsuan SL, Kuo CJ, Chen TH. Effects of L-arabinose efflux on λ Red recombination-mediated gene knockout in multiple-antimicrobial-resistant Salmonella enterica serovar Choleraesuis. Arch Microbiol 2017; 200:219-225. [PMID: 28975374 DOI: 10.1007/s00203-017-1436-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 09/08/2017] [Accepted: 09/20/2017] [Indexed: 11/24/2022]
Abstract
In this study, six swine-derived multiple-antimicrobial-resistant (MAR) strains of Salmonella Choleraesuis (S. Choleraesuis) were demonstrated to possess higher efflux pump activity than the wild-type (WT). L-Arabinose, a common inducer for gene expression, modulated S. Choleraesuis efflux pump activity in a dose-dependent manner. At low L-arabinose concentrations, increasing L-arabinose led to a corresponding increase in fluorophore efflux, while at higher L-arabinose concentrations, increasing L-arabinose decreased fluorophore efflux activity. The WT S. Choleraesuis that lacks TolC (ΔtolC), an efflux protein associated with bacterial antibiotic resistance and virulence, was demonstrated to possess a significantly reduced ability to extrude L-arabinose. Further, due to the rapid export of L-arabinose, an efficient method for recombination-mediated gene knockout, the L-arabinose-inducible bacteriophage λ Red recombinase system, has a reduced recombination frequency (~ 12.5%) in clinically isolated MAR Salmonella strains. An increased recombination frequency (up to 60%) can be achieved using a higher concentration of L-arabinose (fivefold) for genetic manipulation and functional analysis for MAR Salmonella using the λ Red system. The study suggests that L-arabinose serves not only as an inducer of the TolC-dependent efflux system but also acts as a competitive substrate of the efflux system. In addition, understanding the TolC-dependent efflux of L-arabinose should facilitate the optimization of L-arabinose induction in strains with high efflux activity.
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Affiliation(s)
- Shi-Wei Liao
- Graduate Institute of Microbiology and Public Health, National Chung Hsing University, Taichung, Taiwan
| | - Jen-Jie Lee
- Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan
| | - Christopher P Ptak
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Ying-Chen Wu
- Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan
| | - Shih-Ling Hsuan
- Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan
| | - Chih-Jung Kuo
- Department of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan.
| | - Ter-Hsin Chen
- Graduate Institute of Veterinary Pathobiology, National Chung Hsing University, Taichung, Taiwan.
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25
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Jamshidi S, Sutton JM, Rahman KM. Computational Study Reveals the Molecular Mechanism of the Interaction between the Efflux Inhibitor PAβN and the AdeB Transporter from Acinetobacter baumannii. ACS OMEGA 2017; 2:3002-3016. [PMID: 30023681 PMCID: PMC6044690 DOI: 10.1021/acsomega.7b00131] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 06/07/2017] [Indexed: 06/08/2023]
Abstract
Phenylalanine-arginine β-naphthylamide (PAβN) is a broad-spectrum efflux pump inhibitor that has shown to potentiate the activity of antibiotics in Gram-negative bacteria. AdeB is a part of the AdeABC tripartite pump that plays a pivotal role in conferring efflux-mediated resistance in Acinetobacter baumannii. To understand the molecular mechanism of efflux pump inhibition by PAβN, we investigated the interaction of PAβN with AdeB using different computational methods. We observed that PAβN does not have specific binding interactions with the proximal binding site and interacts strongly with the distal binding pocket. The Phe loop located between the proximal and distal binding pockets plays a key role in the PAβN-mediated inhibition and acts as a gate between the binding pockets. Molecular dynamics simulations suggested that PAβN behaved like a climber as we observed switching of the interaction energies between the ligand and the key Phe residues of the binding site during the course of the simulation. PAβN uses the hydrophobic microenvironment formed by Phe residues in the distal binding pocket to keep the binding monomer in the binding conformation. The simulation data suggests that this binding event should result in the inhibition of the peristaltic mechanism and prevent the exporter from extruding any other substrates leading to the inhibition of the tripartite pump.
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Affiliation(s)
- Shirin Jamshidi
- Institute
of Pharmaceutical Science, King’s
College London, London SE1 1DB, U.K.
| | - J. Mark Sutton
- National
Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire SP4 0JG, U.K.
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26
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Zhang CZ, Chen PX, Yang L, Li W, Chang MX, Jiang HX. Coordinated Expression of acrAB-tolC and Eight Other Functional Efflux Pumps Through Activating ramA and marA in Salmonella enterica serovar Typhimurium. Microb Drug Resist 2017. [PMID: 28650690 DOI: 10.1089/mdr.2017.0086] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The aim of this study was to determine the expression of eight other functional transporter genes upon acrAB inactivation and also the expression of acrAB when the function of eight other transporters are impaired in Salmonella enterica. We used single- or multigene deletion mutants (i.e., ΔacrA, ΔacrB, ΔtolC, ΔacrAB, ΔacrEF, ΔacrD, ΔmdsABC, ΔmdtABC, ΔemrAB, ΔmacAB, ΔmdfA, ΔmdtK, ΔacrABramA, ΔacrABmarA, and ΔacrABsoxS) and real time (RT)-PCR to quantify the expression of different pump and regulator genes; infection ability was characterized by adhesion and invasion assays. The expression of acrAB operon was increased upon acrB inactivation. Single deletion of acrA or tolC also increased expression of acrB. The deletion of acrAB increased expression of eight other functional efflux pumps genes and vice versa, in which increased expression of ramA and marA was also detected. Mutants containing single deletions of functional pump genes were attenuated in cells. In conclusion, there is a feedback mechanism that coordinates regulation of AcrAB-TolC and eight other functional efflux pumps through the global transcriptional regulators ramA and marA in S. enterica serovar Typhimurium.
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27
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Thai VC, Lim TK, Le KPU, Lin Q, Nguyen TTH. iTRAQ-based proteome analysis of fluoroquinolone-resistant Staphylococcus aureus. J Glob Antimicrob Resist 2017; 8:82-89. [DOI: 10.1016/j.jgar.2016.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 10/25/2016] [Accepted: 11/05/2016] [Indexed: 12/12/2022] Open
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28
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The Impact of Efflux Pump Inhibitors on the Activity of Selected Non-Antibiotic Medicinal Products against Gram-Negative Bacteria. Molecules 2017; 22:molecules22010114. [PMID: 28085074 PMCID: PMC6155833 DOI: 10.3390/molecules22010114] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 12/12/2016] [Accepted: 01/04/2017] [Indexed: 11/22/2022] Open
Abstract
The potential role of non-antibiotic medicinal products in the treatment of multidrug-resistant Gram-negative bacteria has recently been investigated. It is highly likely that the presence of efflux pumps may be one of the reasons for the weak activity of non-antibiotics, as in the case of some non-steroidal anti-inflammatory drugs (NSAIDs), against Gram-negative rods. The activity of eight drugs of potential non-antibiotic activity, active substance standards, and relevant medicinal products were analysed with and without of efflux pump inhibitors against 180 strains of five Gram-negative rod species by minimum inhibitory concentration (MIC) value determination in the presence of 1 mM MgSO4. Furthermore, the influence of non-antibiotics on the susceptibility of clinical strains to quinolones with or without PAβN (Phe-Arg-β-naphthylamide) was investigated. The impacts of PAβN on the susceptibility of bacteria to non-antibiotics suggests that amitriptyline, alendronate, nicergoline, and ticlopidine are substrates of efflux pumps in Gram-negative rods. Amitriptyline/Amitriptylinum showed the highest direct antibacterial activity, with MICs ranging 100–800 mg/L against all studied species. Significant decreases in the MIC values of other active substances (acyclovir, atorvastatin, and famotidine) tested with pump inhibitors were not observed. The investigated non-antibiotic medicinal products did not alter the MICs of quinolones in the absence and in the presence of PAβN to the studied clinical strains of five groups of species.
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29
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Hooper DC, Jacoby GA. Topoisomerase Inhibitors: Fluoroquinolone Mechanisms of Action and Resistance. Cold Spring Harb Perspect Med 2016; 6:cshperspect.a025320. [PMID: 27449972 DOI: 10.1101/cshperspect.a025320] [Citation(s) in RCA: 255] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Quinolone antimicrobials are widely used in clinical medicine and are the only current class of agents that directly inhibit bacterial DNA synthesis. Quinolones dually target DNA gyrase and topoisomerase IV binding to specific domains and conformations so as to block DNA strand passage catalysis and stabilize DNA-enzyme complexes that block the DNA replication apparatus and generate double breaks in DNA that underlie their bactericidal activity. Resistance has emerged with clinical use of these agents and is common in some bacterial pathogens. Mechanisms of resistance include mutational alterations in drug target affinity and efflux pump expression and acquisition of resistance-conferring genes. Resistance mutations in one or both of the two drug target enzymes are commonly in a localized domain of the GyrA and ParC subunits of gyrase and topoisomerase IV, respectively, and reduce drug binding to the enzyme-DNA complex. Other resistance mutations occur in regulatory genes that control the expression of native efflux pumps localized in the bacterial membrane(s). These pumps have broad substrate profiles that include other antimicrobials as well as quinolones. Mutations of both types can accumulate with selection pressure and produce highly resistant strains. Resistance genes acquired on plasmids confer low-level resistance that promotes the selection of mutational high-level resistance. Plasmid-encoded resistance is because of Qnr proteins that protect the target enzymes from quinolone action, a mutant aminoglycoside-modifying enzyme that also modifies certain quinolones, and mobile efflux pumps. Plasmids with these mechanisms often encode additional antimicrobial resistances and can transfer multidrug resistance that includes quinolones.
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Affiliation(s)
- David C Hooper
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - George A Jacoby
- Lahey Hospital and Medical Center, Burlington, Massachusetts 01805
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30
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Gopal M, Elumalai S, Arumugam S, Durairajpandian V, Kannan MA, Selvam E, Seetharaman S. GyrA ser83 and ParC trp106 Mutations in Salmonella enterica Serovar Typhi Isolated from Typhoid Fever Patients in Tertiary Care Hospital. J Clin Diagn Res 2016; 10:DC14-8. [PMID: 27630841 DOI: 10.7860/jcdr/2016/17677.8153] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/01/2016] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Typhoid fever is endemic in India and other developing countries, causing major public health problems with high morbidity and mortality. The resistance of Salmonella enterica serovar Typhi (S. Typhi) towards commonly prescribed antimicrobials is increasing in developing countries. However, there have been several reports of the therapeutic failure of fluoroquinolones in patients with Salmonella infection. Resistance to quinolones/ fluoroquinolones commonly arises due to target site mutation. AIM The present study was planned to analyze mutation in Quinolone Resistance Determining Region (QRDR) of quinolone resistant Salmonella isolates. MATERIALS AND METHODS A total of 133 S. Typhi isolates (blood (n = 131), stool (n=1) and bone marrow aspirate (n=1)) from tertiary care hospitals in Chennai and Puducherry, were included in this study. Minimum Inhibitory Concentrations (MIC) were carried out according to the Clinical Laboratory Standard Institute (CLSI)guidelines 2014. Mutations in gyrA and parC genes were analyzed by PCR-RFLP (Restriction Fragment Length Polymorphism) method followed by DNA sequencing. RESULTS Of the 133 S. Typhi, 99.2% were resistant to nalidixic acid and 21% were resistant to ciprofloxacin by MIC method. 94% of isolates showed Ser 83 mutation in gyrA and 21.8% of isolates showed Trp106-Gly mutation in parC. CONCLUSION Mutations in gyrA and parC genes are highly prevalent among Salmonella species. Irrational use of fluoroquinolones may increase the accumulation of mutations in the DNA gyrase and topoisomerase encoding genes, which lead to the emergence of high level fluoroquinolone-resistant Salmonella strains in future.
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Affiliation(s)
- Muthu Gopal
- Scientist-C, Model Rural Health Research Unit, National Institute of Epidemiology (ICMR), Primary Health Centre , Nadukallur, Tirunelveli, Tamil Nadu, India
| | - Sathishkumar Elumalai
- Research Scholar, Department of Microbiology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Taramani, Chennai, India
| | - Suresh Arumugam
- Scientist-C, Centre for Drug Discovery and Development, Sathyabama University , Jeppiaar Nagar, Rajiv Gandhi Road, Chennai, India
| | - Vishnuprabu Durairajpandian
- Scientist, National Hub for Healthcare Instrumentation Development, Centre for Biotechnology, Anna University , Chennai, India
| | - Munirajan Arasambattu Kannan
- Professor, Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Taramani, Chennai, India
| | - Esthermary Selvam
- Specialist Cum Head of Department of Microbiology, ESIC Hospital , K.K.Nagar, Chennai, Tamil Nadu, India
| | - Srivani Seetharaman
- Assistant Professor, Department of Microbiology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Taramani, Chennai, India
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31
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Hernando-Amado S, Blanco P, Alcalde-Rico M, Corona F, Reales-Calderón JA, Sánchez MB, Martínez JL. Multidrug efflux pumps as main players in intrinsic and acquired resistance to antimicrobials. Drug Resist Updat 2016; 28:13-27. [PMID: 27620952 DOI: 10.1016/j.drup.2016.06.007] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/31/2016] [Accepted: 06/23/2016] [Indexed: 12/31/2022]
Abstract
Multidrug efflux pumps constitute a group of transporters that are ubiquitously found in any organism. In addition to other functions with relevance for the cell physiology, efflux pumps contribute to the resistance to compounds used for treating different diseases, including resistance to anticancer drugs, antibiotics or antifungal compounds. In the case of antimicrobials, efflux pumps are major players in both intrinsic and acquired resistance to drugs currently in use for the treatment of infectious diseases. One important aspect not fully explored of efflux pumps consists on the identification of effectors able to induce their expression. Indeed, whereas the analysis of clinical isolates have shown that mutants overexpressing these resistance elements are frequently found, less is known on the conditions that may trigger expression of efflux pumps, hence leading to transient induction of resistance in vivo, a situation that is barely detectable using classical susceptibility tests. In the current article we review the structure and mechanisms of regulation of the expression of bacterial and fungal efflux pumps, with a particular focus in those for which a role in clinically relevant resistance has been reported.
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Affiliation(s)
- Sara Hernando-Amado
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain
| | - Paula Blanco
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain
| | - Manuel Alcalde-Rico
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain
| | - Fernando Corona
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain
| | - Jose A Reales-Calderón
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain
| | - María B Sánchez
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain
| | - José L Martínez
- Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología, CSIC, Darwin 3, Cantoblanco, 28049 Madrid, Spain.
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32
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The analysis of the antibiotic resistome offers new opportunities for therapeutic intervention. Future Med Chem 2016; 8:1133-51. [DOI: 10.4155/fmc-2016-0027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Most efforts in the development of antimicrobials have focused on the screening of lethal targets. Nevertheless, the constant expansion of antimicrobial resistance makes the antibiotic resistance determinants themselves suitable targets for finding inhibitors to be used in combination with antibiotics. Among them, inhibitors of antibiotic inactivating enzymes and of multidrug efflux pumps are suitable candidates for improving the efficacy of antibiotics. In addition, the application of systems biology tools is helping to understand the changes in bacterial physiology associated to the acquisition of resistance, including the increased susceptibility to other antibiotics displayed by some antibiotic-resistant mutants. This information is useful for implementing novel strategies based in metabolic interventions or combination of antibiotics for improving the efficacy of antibacterial therapy.
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33
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Eibach D, Al-Emran HM, Dekker DM, Krumkamp R, Adu-Sarkodie Y, Cruz Espinoza LM, Ehmen C, Boahen K, Heisig P, Im J, Jaeger A, von Kalckreuth V, Pak GD, Panzner U, Park SE, Reinhardt A, Sarpong N, Schütt-Gerowitt H, Wierzba TF, Marks F, May J. The Emergence of Reduced Ciprofloxacin Susceptibility inSalmonella entericaCausing Bloodstream Infections in Rural Ghana. Clin Infect Dis 2016; 62 Suppl 1:S32-6. [DOI: 10.1093/cid/civ757] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Oliveira P, Martins NM, Santos M, Pinto F, Büttel Z, Couto NAS, Wright PC, Tamagnini P. The versatile TolC-like Slr1270 in the cyanobacteriumSynechocystissp. PCC 6803. Environ Microbiol 2016; 18:486-502. [DOI: 10.1111/1462-2920.13172] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 11/04/2015] [Accepted: 12/01/2015] [Indexed: 11/28/2022]
Affiliation(s)
- Paulo Oliveira
- i3S - Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC - Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
| | - Nuno M. Martins
- i3S - Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC - Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Faculdade de Ciências; Departamento de Biologia; Universidade do Porto; Porto Portugal
| | - Marina Santos
- i3S - Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC - Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
| | - Filipe Pinto
- i3S - Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC - Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
| | - Zsófia Büttel
- i3S - Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC - Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
| | - Narciso A. S. Couto
- ChELSI Institute; Chemical and Biological Engineering; University of Sheffield; Sheffield UK
| | - Phillip C. Wright
- ChELSI Institute; Chemical and Biological Engineering; University of Sheffield; Sheffield UK
| | - Paula Tamagnini
- i3S - Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC - Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Faculdade de Ciências; Departamento de Biologia; Universidade do Porto; Porto Portugal
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35
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The Influence of Efflux Pump Inhibitors on the Activity of Non-Antibiotic NSAIDS against Gram-Negative Rods. PLoS One 2016; 11:e0147131. [PMID: 26771525 PMCID: PMC4714910 DOI: 10.1371/journal.pone.0147131] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 12/28/2015] [Indexed: 12/31/2022] Open
Abstract
Background Most patients with bacterial infections suffer from fever and various pains that require complex treatments with antibiotics, antipyretics, and analgaesics. The most common drugs used to relieve these symptoms are non-steroidal anti-inflammatory drugs (NSAIDs), which are not typically considered antibiotics. Here, we investigate the effects of NSAIDs on bacterial susceptibility to antibiotics and the modulation of bacterial efflux pumps. Methodology The activity of 12 NSAID active substances, paracetamol (acetaminophen), and eight relevant medicinal products was analyzed with or without pump inhibitors against 89 strains of Gram-negative rods by determining the MICs. Furthermore, the effects of NSAIDs on the susceptibility of clinical strains to antimicrobial agents with or without PAβN (Phe-Arg-β-naphtylamide) were measured. Results The MICs of diclofenac, mefenamic acid, ibuprofen, and naproxen, in the presence of PAβN, were significantly (≥4-fold) reduced, decreasing to 25–1600 mg/L, against the majority of the studied strains. In the case of acetylsalicylic acid only for 5 and 7 out of 12 strains of P. mirabilis and E. coli, respectively, a 4-fold increase in susceptibility in the presence of PAβN was observed. The presence of Aspirin resulted in a 4-fold increase in the MIC of ofloxacin against only two strains of E. coli among 48 tested clinical strains, which included species such as E. coli, K. pneumoniae, P. aeruginosa, and S. maltophilia. Besides, the medicinal products containing the following NSAIDs, diclofenac, mefenamic acid, ibuprofen, and naproxen, did not cause the decrease of clinical strains’ susceptibility to antibiotics. Conclusions The effects of PAβN on the susceptibility of bacteria to NSAIDs indicate that some NSAIDs are substrates for efflux pumps in Gram-negative rods. Morever, Aspirin probably induced efflux-mediated resistance to fluoroquinolones in a few E. coli strains.
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36
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Guérin F. Infections à Enterobacter cloacae complex : résistance aux antibiotiques et traitement. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.antinf.2015.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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37
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Abstract
Quinolone antimicrobials are synthetic and widely used in clinical medicine. Resistance emerged with clinical use and became common in some bacterial pathogens. Mechanisms of resistance include two categories of mutation and acquisition of resistance-conferring genes. Resistance mutations in one or both of the two drug target enzymes, DNA gyrase and DNA topoisomerase IV, are commonly in a localized domain of the GyrA and ParE subunits of the respective enzymes and reduce drug binding to the enzyme-DNA complex. Other resistance mutations occur in regulatory genes that control the expression of native efflux pumps localized in the bacterial membrane(s). These pumps have broad substrate profiles that include quinolones as well as other antimicrobials, disinfectants, and dyes. Mutations of both types can accumulate with selection pressure and produce highly resistant strains. Resistance genes acquired on plasmids can confer low-level resistance that promotes the selection of mutational high-level resistance. Plasmid-encoded resistance is due to Qnr proteins that protect the target enzymes from quinolone action, one mutant aminoglycoside-modifying enzyme that also modifies certain quinolones, and mobile efflux pumps. Plasmids with these mechanisms often encode additional antimicrobial resistances and can transfer multidrug resistance that includes quinolones. Thus, the bacterial quinolone resistance armamentarium is large.
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Affiliation(s)
- David C Hooper
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - George A Jacoby
- Lahey Hospital and Medical Center, Burlington, Massachusetts.,Harvard Medical School, Boston, Massachusetts
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Gantzhorn MR, Olsen JE, Thomsen LE. Importance of sigma factor mutations in increased triclosan resistance in Salmonella Typhimurium. BMC Microbiol 2015; 15:105. [PMID: 25986727 PMCID: PMC4437202 DOI: 10.1186/s12866-015-0444-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 05/12/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Salmonella enterica is the second most common foodborne pathogen. The use of biocides is crucial to prevent spread of foodborne pathogens, and it would be devastating for food safety if Salmonella would become resistant to the disinfectants used. Another concern is that exposure to disinfectants might lead to decreased susceptibility to antibiotics. The current study aimed to identify genetic changes causing high level triclosan resistance in S. enterica serovar Typhimurium and evaluate how these affected antibiotic resistance and efflux pump activity. RESULTS Wild type strains S. Typhimurium 4/74 and DTU3 were adapted to increasing concentrations of the biocide triclosan by serial passage. High level triclosan resistant isolates (MIC > 1000 μg/ml) were obtained. Strains were genome sequenced, and SNPs in fabI, rpoS and rpoD were found to be associated with high level resistance. However, work with defined mutants revealed that a SNP in fabI was not sufficient to obtain high level resistance. This required additional mutations in the sigma factors rpoS or rpoD. The adapted strains showed triclosan-dependent increased efflux, increased fabI expression and reduced susceptibility towards the antibiotics enrofloxacin and sulphamethoxazole/trimethoprim. CONCLUSIONS Medium level triclosan resistance could be obtained by fabI mutations in S. Typhimurium, however, high level resistance was found to require sigma factor mutations in addition to a fabI mutation. Reduced antibiotic sensitivity was observed for the adapted strains, which could be associated with increased efflux.
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Affiliation(s)
- Mette Rørbæk Gantzhorn
- Department of Veterinary Disease Biology, University of Copenhagen, Faculty of Health and Medical Sciences, Stigboejlen 4, 1870, Frederiksberg C, Denmark.
| | - John Elmerdahl Olsen
- Department of Veterinary Disease Biology, University of Copenhagen, Faculty of Health and Medical Sciences, Stigboejlen 4, 1870, Frederiksberg C, Denmark.
| | - Line Elnif Thomsen
- Department of Veterinary Disease Biology, University of Copenhagen, Faculty of Health and Medical Sciences, Stigboejlen 4, 1870, Frederiksberg C, Denmark.
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Webber MA, Whitehead RN, Mount M, Loman NJ, Pallen MJ, Piddock LJV. Parallel evolutionary pathways to antibiotic resistance selected by biocide exposure. J Antimicrob Chemother 2015; 70:2241-8. [PMID: 25953808 PMCID: PMC4500774 DOI: 10.1093/jac/dkv109] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 04/01/2015] [Indexed: 11/30/2022] Open
Abstract
Objectives Biocides are widely used to prevent infection. We aimed to determine whether exposure of Salmonella to various biocides could act as a driver of antibiotic resistance. Methods Salmonella enterica serovar Typhimurium was exposed to four biocides with differing modes of action. Antibiotic-resistant mutants were selected during exposure to all biocides and characterized phenotypically and genotypically to identify mechanisms of resistance. Results All biocides tested selected MDR mutants with decreased antibiotic susceptibility; these occurred randomly throughout the experiments. Mutations that resulted in de-repression of the multidrug efflux pump AcrAB-TolC were seen in MDR mutants. A novel mutation in rpoA was also selected and contributed to the MDR phenotype. Other mutants were highly resistant to both quinolone antibiotics and the biocide triclosan. Conclusions This study shows that exposure of bacteria to biocides can select for antibiotic-resistant mutants and this is mediated by clinically relevant mechanisms of resistance prevalent in human pathogens.
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Affiliation(s)
- Mark A Webber
- Antimicrobials Research Group, School of Immunity and Infection and Institute for Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Rebekah N Whitehead
- Antimicrobials Research Group, School of Immunity and Infection and Institute for Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Manuella Mount
- Antimicrobials Research Group, School of Immunity and Infection and Institute for Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Nick J Loman
- School of Bioscience and Institute for Microbiology & Infection, College of Life and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Mark J Pallen
- Division of Microbiology and Infection, Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK
| | - Laura J V Piddock
- Antimicrobials Research Group, School of Immunity and Infection and Institute for Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
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Li XZ, Plésiat P, Nikaido H. The challenge of efflux-mediated antibiotic resistance in Gram-negative bacteria. Clin Microbiol Rev 2015; 28:337-418. [PMID: 25788514 PMCID: PMC4402952 DOI: 10.1128/cmr.00117-14] [Citation(s) in RCA: 924] [Impact Index Per Article: 102.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The global emergence of multidrug-resistant Gram-negative bacteria is a growing threat to antibiotic therapy. The chromosomally encoded drug efflux mechanisms that are ubiquitous in these bacteria greatly contribute to antibiotic resistance and present a major challenge for antibiotic development. Multidrug pumps, particularly those represented by the clinically relevant AcrAB-TolC and Mex pumps of the resistance-nodulation-division (RND) superfamily, not only mediate intrinsic and acquired multidrug resistance (MDR) but also are involved in other functions, including the bacterial stress response and pathogenicity. Additionally, efflux pumps interact synergistically with other resistance mechanisms (e.g., with the outer membrane permeability barrier) to increase resistance levels. Since the discovery of RND pumps in the early 1990s, remarkable scientific and technological advances have allowed for an in-depth understanding of the structural and biochemical basis, substrate profiles, molecular regulation, and inhibition of MDR pumps. However, the development of clinically useful efflux pump inhibitors and/or new antibiotics that can bypass pump effects continues to be a challenge. Plasmid-borne efflux pump genes (including those for RND pumps) have increasingly been identified. This article highlights the recent progress obtained for organisms of clinical significance, together with methodological considerations for the characterization of MDR pumps.
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Affiliation(s)
- Xian-Zhi Li
- Human Safety Division, Veterinary Drugs Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario, Canada
| | - Patrick Plésiat
- Laboratoire de Bactériologie, Faculté de Médecine-Pharmacie, Centre Hospitalier Régional Universitaire, Université de Franche-Comté, Besançon, France
| | - Hiroshi Nikaido
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
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Increase of multidrug efflux pump expression in fluoroquinolone-resistant Salmonella mutants induced by ciprofloxacin selective pressure. Res Vet Sci 2014; 97:182-6. [DOI: 10.1016/j.rvsc.2014.07.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 07/06/2014] [Accepted: 07/25/2014] [Indexed: 01/13/2023]
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Mezzatesta ML, Gona F, Stefani S. Enterobacter cloacae complex: clinical impact and emerging antibiotic resistance. Future Microbiol 2014; 7:887-902. [PMID: 22827309 DOI: 10.2217/fmb.12.61] [Citation(s) in RCA: 309] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Species of the Enterobacter cloacae complex are widely encountered in nature, but they can act as pathogens. The biochemical and molecular studies on E. cloacae have shown genomic heterogeneity, comprising six species: Enterobacter cloacae, Enterobacter asburiae, Enterobacter hormaechei, Enterobacter kobei, Enterobacter ludwigii and Enterobacter nimipressuralis, E. cloacae and E. hormaechei are the most frequently isolated in human clinical specimens. Phenotypic identification of all species belonging to this taxon is usually difficult and not always reliable; therefore, molecular methods are often used. Although the E. cloacae complex strains are among the most common Enterobacter spp. causing nosocomial bloodstream infections in the last decade, little is known about their virulence-associated properties. By contrast, much has been published on the antibiotic-resistance features of these microorganisms. In fact, they are capable of overproducing AmpC β-lactamases by derepression of a chromosomal gene or by the acquisition of a transferable ampC gene on plasmids conferring the antibiotic resistance. Many other resistance determinants that are able to render ineffective almost all antibiotic families have been recently acquired. Most studies on antimicrobial susceptibility are focused on E. cloacae, E. hormaechei and E. asburiae; these studies reported small variations between the species, and the only significant differences had no discriminating features.
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Affiliation(s)
- Maria Lina Mezzatesta
- Department of Bio-Medical Sciences, Section of Microbiology, University of Catania, Via Androne 81, 95124 Catania, Italy.
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Sherrard LJ, Schaible B, Graham KA, McGrath SJ, McIlreavey L, Hatch J, Wolfgang MC, Muhlebach MS, Gilpin DF, Schneiders T, Elborn JS, Tunney MM. Mechanisms of reduced susceptibility and genotypic prediction of antibiotic resistance in Prevotella isolated from cystic fibrosis (CF) and non-CF patients. J Antimicrob Chemother 2014; 69:2690-8. [PMID: 24917582 DOI: 10.1093/jac/dku192] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVES To investigate mechanisms of reduced susceptibility to commonly used antibiotics in Prevotella cultured from patients with cystic fibrosis (CF), patients with invasive infection and healthy control subjects and to determine whether genotype can be used to predict phenotypic resistance. METHODS The susceptibility of 157 Prevotella isolates to seven antibiotics was compared, with detection of resistance genes (cfxA-type gene, ermF and tetQ), mutations within the CfxA-type β-lactamase and expression of efflux pumps. RESULTS Prevotella isolates positive for a cfxA-type gene had higher MICs of amoxicillin and ceftazidime compared with isolates negative for this gene (P < 0.001). A mutation within the CfxA-type β-lactamase (Y239D) was associated with ceftazidime resistance (P = 0.011). The UK CF isolates were 5.3-fold, 2.7-fold and 5.7-fold more likely to harbour ermF compared with the US CF, UK invasive and UK healthy control isolates, respectively. Higher concentrations of azithromycin (P < 0.001) and clindamycin (P < 0.001) were also required to inhibit the growth of the ermF-positive isolates compared with ermF-negative isolates. Furthermore, tetQ-positive Prevotella isolates had higher MICs of tetracycline (P = 0.001) and doxycycline (P < 0.001) compared with tetQ-negative isolates. Prevotella spp. were also shown, for the first time, to express resistance nodulation division (RND)-type efflux pumps. CONCLUSIONS This study has demonstrated that Prevotella isolated from various sources harbour a common pool of resistance genes and possess RND-type efflux pumps, which may contribute to tetracycline resistance. The findings indicate that antibiotic resistance is common in Prevotella spp., but the genotypic traits investigated do not reflect phenotypic antibiotic resistance in every instance.
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Affiliation(s)
- Laura J Sherrard
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Bettina Schaible
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Kathryn A Graham
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Stef J McGrath
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Leanne McIlreavey
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Joseph Hatch
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Matthew C Wolfgang
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Marianne S Muhlebach
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Deirdre F Gilpin
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Thamarai Schneiders
- Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, Belfast, UK
| | - J Stuart Elborn
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK Centre for Infection & Immunity, School of Medicine, Dentistry & Biomedical Science, Queen's University Belfast, Belfast, UK
| | - Michael M Tunney
- CF & Airways Microbiology Group, Queen's University Belfast, Belfast, UK School of Pharmacy, Queen's University Belfast, Belfast, UK
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Redgrave LS, Sutton SB, Webber MA, Piddock LJV. Fluoroquinolone resistance: mechanisms, impact on bacteria, and role in evolutionary success. Trends Microbiol 2014; 22:438-45. [PMID: 24842194 DOI: 10.1016/j.tim.2014.04.007] [Citation(s) in RCA: 584] [Impact Index Per Article: 58.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 04/11/2014] [Accepted: 04/16/2014] [Indexed: 12/12/2022]
Abstract
Quinolone and fluoroquinolone antibiotics are potent, broad-spectrum agents commonly used to treat a range of infections. Resistance to these agents is multifactorial and can be via one or a combination of target-site gene mutations, increased production of multidrug-resistance (MDR) efflux pumps, modifying enzymes, and/or target-protection proteins. Fluoroquinolone-resistant clinical isolates of bacteria have emerged readily and recent data have shown that resistance to this class of antibiotics can have diverse, species-dependent impacts on host-strain fitness. Here we outline the impacts of quinolone-resistance mutations in relation to the fitness and evolutionary success of mutant strains.
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Affiliation(s)
- Liam S Redgrave
- School of Immunity and Infection, Institute of Microbiology and Infection, Biosciences Building, University Road West, University of Birmingham, Birmingham B15 2TT, UK
| | - Sam B Sutton
- School of Immunity and Infection, Institute of Microbiology and Infection, Biosciences Building, University Road West, University of Birmingham, Birmingham B15 2TT, UK
| | - Mark A Webber
- School of Immunity and Infection, Institute of Microbiology and Infection, Biosciences Building, University Road West, University of Birmingham, Birmingham B15 2TT, UK
| | - Laura J V Piddock
- School of Immunity and Infection, Institute of Microbiology and Infection, Biosciences Building, University Road West, University of Birmingham, Birmingham B15 2TT, UK.
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45
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Fàbrega A, Soto SM, Ballesté-Delpierre C, Fernández-Orth D, Jiménez de Anta MT, Vila J. Impact of quinolone-resistance acquisition on biofilm production and fitness in Salmonella enterica. J Antimicrob Chemother 2014; 69:1815-24. [PMID: 24706735 DOI: 10.1093/jac/dku078] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To investigate the potential relationship between quinolone resistance and biofilm production in a collection of Salmonella enterica clinical isolates and in S. enterica serovar Typhimurium serial mutants with increasing resistance to ciprofloxacin. METHODS Nalidixic acid susceptibility and biofilm formation were assessed in a collection of 122 S. enterica clinical isolates. An in vitro quinolone-resistant mutant, 59-64, was obtained from a biofilm-producing and quinolone-susceptible clinical isolate, 59-wt, in a multistep selection process after increasing ciprofloxacin concentrations. The quinolone resistance mechanisms [target gene and multidrug resistance (MDR) regulatory mutations, MICs of several antibiotics, cell envelope protein analysis, real-time PCR and ciprofloxacin accumulation] were characterized for mutant strains. In addition, analysis of fitness, biofilm formation, rdar morphotype and expression of biofilm-related genes by real-time PCR were also determined. RESULTS Nalidixic acid-susceptible S. enterica strains were more prevalent in producing biofilm than the resistant counterparts. Strain 59-64 acquired five target gene mutations and showed an MDR phenotype. AcrAB and acrF overexpression were ruled out, whereas TolC did show increased expression in 59-64, which, in addition, accumulated less ciprofloxacin. Consistently, increased ramA expression was seen in 59-64 and attributed to a mutation within its promoter. Reduced biofilm production related to diminished csgB expression as well as reduced fitness was seen for 59-64, which was unable to form the rdar morphotype. CONCLUSIONS Quinolone resistance acquisition may be associated with decreased production of biofilm due to lower csgB expression. Efflux, biofilm production and fitness seem to be interrelated.
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Affiliation(s)
- Anna Fàbrega
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain
| | - Sara M Soto
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain
| | - Clara Ballesté-Delpierre
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain
| | - Dietmar Fernández-Orth
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain
| | - M Teresa Jiménez de Anta
- Department of Clinical Microbiology, Hospital Clínic, School of Medicine, University of Barcelona, Barcelona, Spain
| | - Jordi Vila
- Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain Department of Clinical Microbiology, Hospital Clínic, School of Medicine, University of Barcelona, Barcelona, Spain
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Baucheron S, Monchaux I, Le Hello S, Weill FX, Cloeckaert A. Lack of efflux mediated quinolone resistance in Salmonella enterica serovars Typhi and Paratyphi A. Front Microbiol 2014; 5:12. [PMID: 24478769 PMCID: PMC3902205 DOI: 10.3389/fmicb.2014.00012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 01/09/2014] [Indexed: 11/23/2022] Open
Abstract
Salmonella enterica serovars Typhi and Paratyphi A isolates from human patients in France displaying different levels of resistance to quinolones or fluoroquinolones were studied for resistance mechanisms to these antimicrobial agents. All resistant isolates carried either single or multiple target gene mutations (i.e., in gyrA, gyrB, or parC) correlating with the resistance levels observed. Active efflux, through upregulation of multipartite efflux systems, has also been previously reported as contributing mechanism for other serovars. Therefore, we investigated also the occurrence of non-target gene mutations in regulatory regions affecting efflux pump expression. However, no mutation was detected in these regions in both Typhi and Paratyphi isolates of this study. Besides, no overexpression of the major efflux systems was observed for these isolates. Nevertheless, a large deletion of 2334 bp was identified in the acrS-acrE region of all S. Typhi strains but which did not affect the resistance phenotype. As being specific to S. Typhi, this deletion could be used for specific molecular detection purposes. In conclusion, the different levels of quinolone or FQ resistance in both S. Typhi and S. Paratyphi A seem to rely only on target modifications.
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Affiliation(s)
- Sylvie Baucheron
- UMR1282 Infectiologie et Santé Publique, Institut National de la Recherche Agronomique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais de Tours Tours, France
| | - Isabelle Monchaux
- UMR1282 Infectiologie et Santé Publique, Institut National de la Recherche Agronomique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais de Tours Tours, France
| | - Simon Le Hello
- Unité des Bactéries Pathogènes Entériques, Centre National de Référence des Escherichia coli, Institut Pasteur, Shigella et Salmonella Paris, France
| | - François-Xavier Weill
- Unité des Bactéries Pathogènes Entériques, Centre National de Référence des Escherichia coli, Institut Pasteur, Shigella et Salmonella Paris, France
| | - Axel Cloeckaert
- UMR1282 Infectiologie et Santé Publique, Institut National de la Recherche Agronomique Nouzilly, France ; UMR1282 Infectiologie et Santé Publique, Université François Rabelais de Tours Tours, France
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Gunasekera TS, Striebich RC, Mueller SS, Strobel EM, Ruiz ON. Transcriptional profiling suggests that multiple metabolic adaptations are required for effective proliferation of Pseudomonas aeruginosa in jet fuel. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:13449-13458. [PMID: 24164330 DOI: 10.1021/es403163k] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Fuel is a harsh environment for microbial growth. However, some bacteria can grow well due to their adaptive mechanisms. Our goal was to characterize the adaptations required for Pseudomonas aeruginosa proliferation in fuel. We have used DNA-microarrays and RT-PCR to characterize the transcriptional response of P. aeruginosa to fuel. Transcriptomics revealed that genes essential for medium- and long-chain n-alkane degradation including alkB1 and alkB2 were transcriptionally induced. Gas chromatography confirmed that P. aeruginosa possesses pathways to degrade different length n-alkanes, favoring the use of n-C11-18. Furthermore, a gamut of synergistic metabolic pathways, including porins, efflux pumps, biofilm formation, and iron transport, were transcriptionally regulated. Bioassays confirmed that efflux pumps and biofilm formation were required for growth in jet fuel. Furthermore, cell homeostasis appeared to be carefully maintained by the regulation of porins and efflux pumps. The Mex RND efflux pumps were required for fuel tolerance; blockage of these pumps precluded growth in fuel. This study provides a global understanding of the multiple metabolic adaptations required by bacteria for survival and proliferation in fuel-containing environments. This information can be applied to improve the fuel bioremediation properties of bacteria.
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Affiliation(s)
- Thusitha S Gunasekera
- University of Dayton Research Institute, University of Dayton , Dayton Ohio 45469, United States
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Resistance to Fluoroquinolone by a Combination of Efflux and Target Site Mutations in Enteroaggregative Escherichia coli Isolated in Korea. Osong Public Health Res Perspect 2013; 3:239-44. [PMID: 24159520 PMCID: PMC3747663 DOI: 10.1016/j.phrp.2012.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 10/25/2012] [Indexed: 12/23/2022] Open
Abstract
Objectives Enteroaggregative Escherichia coli (EAEC) was recently reported as a major diarrheagenic pathogen in infant and adult travelers, both in developing and developed countries. EAEC strains are known to be highly resistant to antibiotics including quinolones. Therefore in this study we have determined the various mechanisms of quinolone resistance in EAEC strains isolated in Korea. Methods For 26 EAEC strains highly resistant to fluoroquinolone, minimal inhibitory concentrations for fluoroquinolones were determined, mutations in the quinolone target genes were identified by PCR and sequencing, the presence of transferable quinolone resistance mechanism were identified by PCR, and the contribution of the efflux pump was determined by synergy tests using a proton pump inhibitor. The expression levels of efflux pump-related genes were identified by relative quantification using real-time PCR. Results Apart from two, all tested isolates had common mutations on GyrA (Ser83Leu and Ser87Gly) and ParC (Ser80Gln). Isolates EACR24 and EACR39 had mutations that have not been reported previously: Ala81Pro in ParC and Arg157Gly in GyrA, respectively. Increased susceptibility of all the tested isolates to ciprofloxacin and norfloxacin in the presence of the pump inhibitor implies that efflux pumps contributed to the resistance against fluoroquinolones. Expression of the efflux pump-related genes, tolC, mdfA, and ydhE, were induced in isolates EACR 07, EACR 29, and EACR 33 in the presence of ciprofloxacin. Conclusion These results indicate that quinolone resistance of EAEC strains mainly results from the combination of mutations in the target enzyme and an increased expression of efflux pump-related genes. The mutations Ala81Pro in ParC and Arg157Gly in GyrA have not been reported previously the exact influence of these mutations should be investigated further.
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Analysis of triclosan-selected Salmonella enterica mutants of eight serovars revealed increased aminoglycoside susceptibility and reduced growth rates. PLoS One 2013; 8:e78310. [PMID: 24205194 PMCID: PMC3799642 DOI: 10.1371/journal.pone.0078310] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 09/19/2013] [Indexed: 11/19/2022] Open
Abstract
The biocide triclosan (TRC) is used in a wide range of household, personal care, veterinary, industrial and medical products to control microbial growth. This extended use raises concerns about a possible association between the application of triclosan and the development of antibiotic resistance. In the present study we determined triclosan mutant prevention concentrations (MPC) for Salmonella enterica isolates of eight serovars and investigated selected mutants for their mechanisms mediating decreased susceptibility to triclosan. MPCTRC values were 8 - 64-fold higher than MIC values and ranged between 1 - 16 µg/ml. The frequencies at which mutants were selected varied between 1.3 x 10-10 - 9.9 x 10-11. Even if MIC values of mutants decreased by 3-7 dilution steps in the presence of the efflux pump inhibitor Phe-Arg-β-naphtylamide, only minor changes were observed in the expression of genes encoding efflux components or regulators, indicating that neither the major multidrug efflux pump AcrAB-TolC nor AcrEF are up-regulated in triclosan-selected mutants. Nucleotide sequence comparisons confirmed the absence of alterations in the regulatory regions acrRA, soxRS, marORAB, acrSE and ramRA of selected mutants. Single bp and deduced Gly93→Val amino acid exchanges were present in fabI, the target gene of triclosan, starting from a concentration of 1 µg/ml TRC used for MPC determinations. The fabI genes were up to 12.4-fold up-regulated. Complementation experiments confirmed the contribution of Gly93→Val exchanges and fabI overexpression to decreased triclosan susceptibility. MIC values of mutants compared to parent strains were even equal or resulted in a more susceptible phenotype (1-2 dilution steps) for the aminoglycoside antibiotics kanamycin and gentamicin as well as for the biocide chlorhexidine. Growth rates of selected mutants were significantly lower and hence, might partly explain the rare occurrence of Salmonella field isolates exhibiting decreased susceptibility to triclosan.
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50
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Baucheron S, Le Hello S, Doublet B, Giraud E, Weill FX, Cloeckaert A. ramR mutations affecting fluoroquinolone susceptibility in epidemic multidrug-resistant Salmonella enterica serovar Kentucky ST198. Front Microbiol 2013; 4:213. [PMID: 23914184 PMCID: PMC3728480 DOI: 10.3389/fmicb.2013.00213] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 07/09/2013] [Indexed: 11/13/2022] Open
Abstract
A screening for non-target mutations affecting fluoroquinolone susceptibility was conducted in epidemic multidrug-resistant Salmonella enterica serovar Kentucky ST198. Among a panel of representative isolates (n = 27), covering the epidemic, only three showed distinct mutations in ramR resulting in enhanced expression of genes encoding the AcrAB-TolC efflux system and low increase in ciprofloxacin MIC. No mutations were detected in other regulatory regions of this efflux system. Ciprofloxacin resistance in serovar Kentucky ST198 is thus currently mainly due to multiple target gene mutations.
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Affiliation(s)
- Sylvie Baucheron
- INRA, UMR1282 Infectiologie et Santé Publique Nouzilly, France ; Université François Rabelais de Tours, UMR1282 Infectiologie et Santé Publique Tours, France
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