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Chanket W, Pipatthana M, Sangphukieo A, Harnvoravongchai P, Chankhamhaengdecha S, Janvilisri T, Phanchana M. The complete catalog of antimicrobial resistance secondary active transporters in Clostridioides difficile: evolution and drug resistance perspective. Comput Struct Biotechnol J 2024; 23:2358-2374. [PMID: 38873647 PMCID: PMC11170357 DOI: 10.1016/j.csbj.2024.05.027] [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: 02/08/2024] [Revised: 05/01/2024] [Accepted: 05/16/2024] [Indexed: 06/15/2024] Open
Abstract
Secondary active transporters shuttle substrates across eukaryotic and prokaryotic membranes, utilizing different electrochemical gradients. They are recognized as one of the antimicrobial efflux pumps among pathogens. While primary active transporters within the genome of C. difficile 630 have been completely cataloged, the systematical study of secondary active transporters remains incomplete. Here, we not only identify secondary active transporters but also disclose their evolution and role in drug resistance in C. difficile 630. Our analysis reveals that C. difficile 630 carries 147 secondary active transporters belonging to 27 (super)families. Notably, 50 (34%) of them potentially contribute to antimicrobial resistance (AMR). AMR-secondary active transporters are structurally classified into five (super)families: the p-aminobenzoyl-glutamate transporter (AbgT), drug/metabolite transporter (DMT) superfamily, major facilitator (MFS) superfamily, multidrug and toxic compound extrusion (MATE) family, and resistance-nodulation-division (RND) family. Surprisingly, complete RND genes found in C. difficile 630 are likely an evolutionary leftover from the common ancestor with the diderm. Through protein structure comparisons, we have potentially identified six novel AMR-secondary active transporters from DMT, MATE, and MFS (super)families. Pangenome analysis revealed that half of the AMR-secondary transporters are accessory genes, which indicates an important role in adaptive AMR function rather than innate physiological homeostasis. Gene expression profile firmly supports their ability to respond to a wide spectrum of antibiotics. Our findings highlight the evolution of AMR-secondary active transporters and their integral role in antibiotic responses. This marks AMR-secondary active transporters as interesting therapeutic targets to synergize with other antibiotic activity.
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Affiliation(s)
- Wannarat Chanket
- Graduate Program in Molecular Medicine, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Methinee Pipatthana
- Department of Microbiology, Faculty of Public Health, Mahidol University, Bangkok, Thailand
| | - Apiwat Sangphukieo
- Center of Multidisciplinary Technology for Advanced Medicine (CMUTEAM), Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | | | | | - Tavan Janvilisri
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Matthew Phanchana
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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Brouwer L, Carroll A, McNamara E. Genotypic and phenotypic antimicrobial resistance of Irish Clostridioides difficile isolates, 2022. Anaerobe 2024; 88:102857. [PMID: 38670525 DOI: 10.1016/j.anaerobe.2024.102857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/12/2024] [Accepted: 04/14/2024] [Indexed: 04/28/2024]
Abstract
OBJECTIVES Infection with Clostridioides difficile usually occurs after antibiotic treatment for other infections and can cause gastro-intestinal disorders of variable severity. C. difficile can be resistant to a wide spectrum of antimicrobials. Detection of antimicrobial resistance (AMR) is important to direct optimal treatment and surveillance of AMR patterns in the overall population. Correlation between genotypic markers and phenotypic AMR is not yet well defined. The aim for this study is to assess whether and to what extent genotypic determinants of AMR correlate with phenotypic resistance. METHODS C. difficile isolates (n = 99) were phenotypically characterized for resistance to eight antibiotics using Sensititre plates or E-tests. Their genomes were screened for genetic markers of resistance. Accuracy, sensitivity, specificity, positive and negative predictive values were calculated. RESULTS We found high rates of resistance (>50 %) to cefoxitin and clindamycin, intermediate rates of resistance (10 %-50 %) to moxifloxacin and tetracycline and low rates of resistance (<10 %) to imipenem, metronidazole, vancomycin, and rifampicin. For moxifloxacin, tetracycline, and clindamycin, we found a good correlation between genotypic and phenotypic AMR, with an overall accuracy of 98 % (95 % CI 93%-100 %), 78 % (95 % CI 68%-86 %) and 86 % (95 % CI 77%-92 %) respectively. For the other five antibiotics, accurate estimates on the correlation could not be made. CONCLUSION Our results suggest that for moxifloxacin, tetracycline and clindamycin, phenotypic resistance in C. difficile can be predicted by genetic indicators and used for public health purposes. However, for the other five antibiotics, the model is not accurate and further development is necessary.
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Affiliation(s)
- Lieke Brouwer
- Clostridioides Difficile National Reference Laboratory, Public Health Laboratory, Health Service Executive, Cherry Orchard Hospital, Dublin, Ireland; European Public Health Microbiology Training Programme (EUPHEM), European Centre for Disease Prevention and Control, Stockholm, Sweden.
| | - Anne Carroll
- Clostridioides Difficile National Reference Laboratory, Public Health Laboratory, Health Service Executive, Cherry Orchard Hospital, Dublin, Ireland; European Public Health Microbiology Training Programme (EUPHEM), European Centre for Disease Prevention and Control, Stockholm, Sweden
| | - Eleanor McNamara
- Clostridioides Difficile National Reference Laboratory, Public Health Laboratory, Health Service Executive, Cherry Orchard Hospital, Dublin, Ireland; European Public Health Microbiology Training Programme (EUPHEM), European Centre for Disease Prevention and Control, Stockholm, Sweden
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Li X, Wang Y, Cao R, Xiao F, Wang X, Ye L, Xiao Y, Li D, Zhang T. Antimicrobial Resistance of Clostridioides difficile in Children from a Tertiary Pediatric Hospital in Shanghai, China. Infect Drug Resist 2024; 17:329-339. [PMID: 38293314 PMCID: PMC10826549 DOI: 10.2147/idr.s441312] [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: 09/21/2023] [Accepted: 12/13/2023] [Indexed: 02/01/2024] Open
Abstract
Background Our previous study reported a high rate of recurrence in children with Clostridioides difficile (C. difficile) infection (CDI) after conventional antibiotic therapy. Here, we aimed to explore whether metronidazole and vancomycin resistant C. difficile isolates are circulating in pediatric CDI. Methods Antimicrobial susceptibility testing (AST) using the agar dilution method according to the Clinical and Laboratory Standard Institute (CLSI) were performed on C. difficile isolates collected from children with CDI between 2019 and 2022 at the Shanghai Children's Hospital. Whole-genome sequencing (WGS) was performed on all C. difficile isolates, and the presence of antibiotic resistance genes (ARGs) were identified using Resfinder and the Comprehensive Antibiotic Resistance Database (CARD). The presence of plasmid pCD-METRO was detected using SRST2 (v0.2.0) against 8 pCD-METRO coding sequences. Results A total of 50 C. difficile isolates were collected from stools of CDI children. The overall resistance rate on all isolates was 30.00% for metronidazole, 6.00% for vancomycin, 0% for rifaximin, 2.00% for rifampin, 24.00% for meropenem, 100.00% for ceftriaxone and clindamycin, 86.00% for erythromycin, 30.0% for levofloxacin, and 50.0% for tetracycline. Multidrug-resistant (MDR) was presented in 44 isolates (88.00%). Sixteen reported potential ARGs relating with resistance to antibiotic classes of aminoglycoside (AAC(6')-Ie-APH(2")-Ia, aad(6), ANT(6)-Ib, APH(2")-If, APH(3')-IIIa), lincosamide-clindamycin-erythromycin (ErmB, ErmQ), fluoroquinolones (CdeA), glycopeptides (vanRG), nucleoside (SAT-4), tetracycline (tetM, tetA(P), tetB(P), tetO), and trimethoprim (dfrF) were identified. However, the pCD-METRO plasmid and vanA/B were not detected in any isolates. Conclusion C. difficile isolates from children with reduced susceptibility to metronidazole and vancomycin are emerging in pediatric CDI in China. The lack of pCD-METRO plasmid and vanA/B associated with reduced antibiotic susceptibility suggests there are additional mechanisms of resistance.
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Affiliation(s)
- Xiaolu Li
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Yizhong Wang
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
- Gut Microbiota and Metabolic Research Center, Institute of Pediatric Infection, Immunity and Critical Care Medicine, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Rong Cao
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Fangfei Xiao
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Xufei Wang
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Lin Ye
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Yongmei Xiao
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Dan Li
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
| | - Ting Zhang
- Department of Gastroenterology, Hepatology and Nutrition, Shanghai Children’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
- Gut Microbiota and Metabolic Research Center, Institute of Pediatric Infection, Immunity and Critical Care Medicine, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China
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Spigaglia P, Mastrantonio P, Barbanti F. Antibiotic Resistances of Clostridioides difficile. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1435:169-198. [PMID: 38175476 DOI: 10.1007/978-3-031-42108-2_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
The rapid evolution of antibiotic resistance in Clostridioides difficile and the consequent effects on prevention and treatment of C. difficile infections (CDIs) are a matter of concern for public health. Antibiotic resistance plays an important role in driving C. difficile epidemiology. Emergence of new types is often associated with the emergence of new resistances, and most of the epidemic C. difficile clinical isolates is currently resistant to multiple antibiotics. In particular, it is to worth to note the recent identification of strains with reduced susceptibility to the first-line antibiotics for CDI treatment and/or for relapsing infections. Antibiotic resistance in C. difficile has a multifactorial nature. Acquisition of genetic elements and alterations of the antibiotic target sites, as well as other factors, such as variations in the metabolic pathways or biofilm production, contribute to the survival of this pathogen in the presence of antibiotics. Different transfer mechanisms facilitate the spread of mobile elements among C. difficile strains and between C. difficile and other species. Furthermore, data indicate that both genetic elements and alterations in the antibiotic targets can be maintained in C. difficile regardless of the burden imposed on fitness, and therefore resistances may persist in C. difficile population in absence of antibiotic selective pressure.
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Affiliation(s)
- Patrizia Spigaglia
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
| | - Paola Mastrantonio
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Fabrizio Barbanti
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
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Marcos P, Whyte P, Burgess C, Ekhlas D, Bolton D. Detection and Genomic Characterisation of Clostridioides difficile from Spinach Fields. Pathogens 2022; 11:1310. [PMID: 36365061 PMCID: PMC9695345 DOI: 10.3390/pathogens11111310] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/27/2022] [Accepted: 11/02/2022] [Indexed: 10/29/2023] Open
Abstract
Despite an increased incidence of Clostridioides difficile infections, data on the reservoirs and dissemination routes of this bacterium are limited. This study examined the prevalence and characteristics of C. difficile isolates in spinach fields. C. difficile was detected in 2/60 (3.3%) of spinach and 6/60 (10%) of soil samples using culture-based techniques. Whole genome sequencing (WGS) analysis identified the spinach isolates as belonging to the hypervirulent clade 5, sequence type (ST) 11, ribotypes (RT) 078 and 126 and carried the genes encoding toxins A, B and CDT. The soil isolates belonged to clade 1 with different toxigenic ST/RT (ST19/RT614, ST12/RT003, ST46/RT087, ST16/RT050, ST49/RT014/0) strains and one non-toxigenic ST79/RT511 strain. Antimicrobial resistance to erythromycin (one spinach isolate), rifampicin (two soil isolates), clindamycin (one soil isolate), both moxifloxacin and rifampicin (one soil isolate), and multi-drug resistance to erythromycin, vancomycin and rifampicin (two soil isolates) were observed using the E test, although a broader range of resistance genes were detected using WGS. Although the sample size was limited, our results demonstrate the presence of C. difficile in horticulture and provide further evidence that there are multiple sources and dissemination routes for these bacteria.
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Affiliation(s)
- Pilar Marcos
- Teagasc Food Research Centre, Ashtown, 15 Dublin, D15 DY05 Dublin, Ireland
- School of Veterinary Medicine, University College Dublin, Belfield, 4 Dublin, D04 V1W8 Dublin, Ireland
| | - Paul Whyte
- School of Veterinary Medicine, University College Dublin, Belfield, 4 Dublin, D04 V1W8 Dublin, Ireland
| | - Catherine Burgess
- Teagasc Food Research Centre, Ashtown, 15 Dublin, D15 DY05 Dublin, Ireland
| | - Daniel Ekhlas
- Teagasc Food Research Centre, Ashtown, 15 Dublin, D15 DY05 Dublin, Ireland
- School of Veterinary Medicine, University College Dublin, Belfield, 4 Dublin, D04 V1W8 Dublin, Ireland
| | - Declan Bolton
- Teagasc Food Research Centre, Ashtown, 15 Dublin, D15 DY05 Dublin, Ireland
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Garcia ÍR, de Oliveira Garcia FA, Pereira PS, Coutinho HDM, Siyadatpanah A, Norouzi R, Wilairatana P, de Lourdes Pereira M, Nissapatorn V, Tintino SR, Rodrigues FFG. Microbial resistance: The role of efflux pump superfamilies and their respective substrates. Life Sci 2022; 295:120391. [PMID: 35149116 DOI: 10.1016/j.lfs.2022.120391] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 02/02/2022] [Accepted: 02/06/2022] [Indexed: 12/24/2022]
Abstract
The microorganism resistance to antibiotics has become one of the most worrying issues for science due to the difficulties related to clinical treatment and the rapid spread of diseases. Efflux pumps are classified into six groups of carrier proteins that are part of the different types of mechanisms that contribute to resistance in microorganisms, allowing their survival. The present study aimed to carry out a bibliographic review on the superfamilies of carriers in order to understand their compositions, expressions, substrates, and role in intrinsic resistance. At first, a search for manuscripts was carried out in the databases Medline, Pubmed, ScienceDirect, and Scielo, using as descriptors: efflux pump, expression, pump inhibitors and efflux superfamily. For article selection, two criteria were taken into account: for inclusion, those published between 2000 and 2020, including textbooks, and for exclusion, duplicates and academic collections. In this research, 139,615 published articles were obtained, with 312 selected articles and 7 book chapters that best met the aim. From the comprehensive analysis, it was possible to consider that the chromosomes and genetic elements can contain genes encoding efflux pumps and are responsible for multidrug resistance. Even though this is a well-explored topic in the scientific community, understanding the behavior of antibiotics as substrates that increase the expression of pump-encoding genes has challenged medicine. This review study succinctly summarizes the most relevant features of these systems, as well as their contribution to multidrug resistance.
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Affiliation(s)
| | | | | | | | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand, Iran
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials & Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences and Research Excellence Center for Innovation and Health, Walailak University, Thailand
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Whole genome sequence of bacteremic Clostridium tertium in a World War I soldier, 1914. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100089. [PMID: 34984406 PMCID: PMC8693014 DOI: 10.1016/j.crmicr.2021.100089] [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: 08/05/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 11/21/2022] Open
Abstract
This original article is the first report of isolate and culture of a bacterium from ancient human samples and dental pulp in particular. The dental pulp is a mirror of the individual's infectious state at the time of death. Ancient dental pulp culture yielded to the identification and isolation of the bacterium Clostridium tertium responsible for septicaemia during World War I,.
Background Dental pulp, encapsulating a blood drop, could be used to diagnose pathogen bacteraemia in archaeological materials using DNA-based techniques. We questioned the viability of such ancient pathogens preserved in ancient dental pulp. Methods After meticulous decontamination of 32 teeth collected from 31 World War I soldiers exhumed in Spincourt, France, dental pulps were extracted and cultured under strict anaerobiosis. Colonies were identified by mass spectrometry and whole genome sequencing. Fluorescent in situ hybridisation (FISH) was used for the direct microscopic detection of pathogens of interest in the dental pulp. All the experimental procedures included negative controls, notably sediments in contact with individual SQ517 to ensure that results did not arise from contamination. Findings Clostridium tertium was detected by FISH in two dental pulp specimens taken from a 1914 soldier. After a two-day incubation period, both dental pulp samples grew colonies identified by mass spectrometry and genome sequencing as C. tertium; whereas negative controls remained free of C. tertium in all the observations, and no C. tertium was founded in sediments. Skeletal remains of this soldier exhibited two notches in the left tibia evocative of a cold steel wound, and a probably fatal unhealed bullet impact in the hip bone. Interpretation Data indicated the presence of C. tertium in the dental pulp at the time of the death of one World War I soldier, in 1914. This observation diagnosed C. tertium bacteraemia, with war wounds as the probable portal of entry for C. tertium. Our C. tertium strains ante-dated by three years, the princeps description of this deadly opportunistic pathogen.
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O’Grady K, Knight DR, Riley TV. Antimicrobial resistance in Clostridioides difficile. Eur J Clin Microbiol Infect Dis 2021; 40:2459-2478. [DOI: 10.1007/s10096-021-04311-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/08/2021] [Indexed: 02/08/2023]
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Wickramage I, Spigaglia P, Sun X. Mechanisms of antibiotic resistance of Clostridioides difficile. J Antimicrob Chemother 2021; 76:3077-3090. [PMID: 34297842 DOI: 10.1093/jac/dkab231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Clostridioides difficile (CD) is one of the top five urgent antibiotic resistance threats in USA. There is a worldwide increase in MDR of CD, with emergence of novel strains which are often more virulent and MDR. Antibiotic resistance in CD is constantly evolving with acquisition of novel resistance mechanisms, which can be transferred between different species of bacteria and among different CD strains present in the clinical setting, community, and environment. Therefore, understanding the antibiotic resistance mechanisms of CD is important to guide optimal antibiotic stewardship policies and to identify novel therapeutic targets to combat CD as well as other bacteria. Epidemiology of CD is driven by the evolution of antibiotic resistance. Prevalence of different CD strains and their characteristic resistomes show distinct global geographical patterns. Understanding epidemiologically driven and strain-specific characteristics of antibiotic resistance is important for effective epidemiological surveillance of antibiotic resistance and to curb the inter-strain and -species spread of the CD resistome. CD has developed resistance to antibiotics with diverse mechanisms such as drug alteration, modification of the antibiotic target site and extrusion of drugs via efflux pumps. In this review, we summarized the most recent advancements in the understanding of mechanisms of antibiotic resistance in CD and analysed the antibiotic resistance factors present in genomes of a few representative well known, epidemic and MDR CD strains found predominantly in different regions of the world.
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Affiliation(s)
- Ishani Wickramage
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Down Blvd, Tampa, FL 33612, USA
| | - Patrizia Spigaglia
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Xingmin Sun
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Down Blvd, Tampa, FL 33612, USA
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Identification and Transferability of Tetracycline Resistance in Streptococcus thermophilus during Milk Fermentation, Storage, and Gastrointestinal Transit. FERMENTATION-BASEL 2021. [DOI: 10.3390/fermentation7020065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The existence of antibiotic-resistant bacteria in food products, particularly those carrying acquired resistance genes, has increased concerns about the transmission of these genes from beneficial microbes to human pathogens. In this study, we evaluated the antibiotic resistance-susceptibility patterns of 16 antibiotics in eight S. thermophilus strains, whose genome sequence is available, using phenotypic and genomic approaches. The minimal inhibitory concentration values collected revealed intermediate resistance to aminoglycosides, whereas susceptibility was detected for different classes of β-lactams, quinolones, glycopeptide, macrolides, and sulfonamides in all strains. A high tetracycline resistance level has been detected in strain M17PTZA496, whose genome analysis indicated the presence of the tet(S) gene and the multidrug and toxic compound extrusion (MATE) family efflux pump. Moreover, an in-depth genomic analysis revealed genomic islands and an integrative and mobilizable element (IME) in the proximity of the gene tet(S). However, despite the presence of a prophage, genomic islands, and IME, no horizontal gene transfer was detected to Lactobacillus delbrueckii subsp. lactis DSM 20355 and Lactobacillusrhamnosus GG during 24 h of skim milk fermentation, 2 weeks of refrigerated storage, and 4 h of simulated gastrointestinal transit.
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Muñoz M, Restrepo-Montoya D, Kumar N, Iraola G, Camargo M, Díaz-Arévalo D, Roa-Molina NS, Tellez MA, Herrera G, Ríos-Chaparro DI, Birchenall C, Pinilla D, Pardo-Oviedo JM, Rodríguez-Leguizamón G, Josa DF, Lawley TD, Patarroyo MA, Ramírez JD. Integrated genomic epidemiology and phenotypic profiling of Clostridium difficile across intra-hospital and community populations in Colombia. Sci Rep 2019; 9:11293. [PMID: 31383872 PMCID: PMC6683185 DOI: 10.1038/s41598-019-47688-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/22/2019] [Indexed: 02/06/2023] Open
Abstract
Clostridium difficile, the causal agent of antibiotic-associated diarrhea, has a complex epidemiology poorly studied in Latin America. We performed a robust genomic and phenotypic profiling of 53 C. difficile clinical isolates established from diarrheal samples from either intrahospital (IH) or community (CO) populations in central Colombia. In vitro tests were conducted to evaluate the cytopathic effect, the minimum inhibitory concentration of ten antimicrobial agents, the sporulation efficiency and the colony forming ability. Eleven different sequence types (STs) were found, the majority present individually in each sample, however in three samples two different STs were isolated. Interestingly, CO patients were infected with STs associated with hypervirulent strains (ST-1 in Clade-2). Three coexistence events (two STs simultaneously detected in the same sample) were observed always involving ST-8 from Clade-1. A total of 2,502 genes were present in 99% of the isolates with 95% of identity or more, it represents a core genome of 28.6% of the 8,735 total genes identified in the set of genomes. A high cytopathic effect was observed for the isolates positive for the two main toxins but negative for binary toxin (TcdA+/TcdB+/CDT- toxin production type), found only in Clade-1. Molecular markers conferring resistance to fluoroquinolones (cdeA and gyrA) and to sulfonamides (folP) were the most frequent in the analyzed genomes. In addition, 15 other markers were found mostly in Clade-2 isolates. These results highlight the regional differences that C. difficile isolates display, being in this case the CO isolates the ones having a greater number of accessory genes and virulence-associated factors.
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Affiliation(s)
- Marina Muñoz
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
- Posgrado Interfacultades Doctorado en Biotecnología, Facultad de Ciencias, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Daniel Restrepo-Montoya
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
- Genomics and Bioinformatics Department, North Dakota State University, Fargo, North Dakota, USA
| | - Nitin Kumar
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
| | - Gregorio Iraola
- Microbial Genomics Laboratory, Institut Pasteur Montevideo, Montevideo, Uruguay
- Center for Integrative Biology, Universidad Mayor, Santiago de Chile, Chile
| | - Milena Camargo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
- School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Diana Díaz-Arévalo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
- Faculty of Animal Sciences, Universidad de Ciencias Aplicadas y Ambientales (UDCA), Bogotá, Colombia
- Hygea group, Faculty of Health Sciences, Universidad de Boyacá, Tunja, Colombia
| | - Nelly S Roa-Molina
- Centro de Investigaciones Odontológicas, Facultad de Odontología, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Mayra A Tellez
- Centro de Investigaciones Odontológicas, Facultad de Odontología, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Giovanny Herrera
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
- PhD Programme in Biomedical and Biological Sciences, Faculty of Natural Sciences and Mathematics/School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Dora I Ríos-Chaparro
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia
| | - Claudia Birchenall
- Hospital Universitario Mayor - Méderi, Universidad del Rosario, Bogotá, Colombia
| | - Darío Pinilla
- Hospital Universitario Mayor - Méderi, Universidad del Rosario, Bogotá, Colombia
| | - Juan M Pardo-Oviedo
- Hospital Universitario Mayor - Méderi, Universidad del Rosario, Bogotá, Colombia
| | | | | | - Trevor D Lawley
- Host-Microbiota Interactions Laboratory, Wellcome Sanger Institute, Hinxton, UK
| | - Manuel A Patarroyo
- Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Bogotá, Colombia
- School of Medicine and Health Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Juan David Ramírez
- Grupo de Investigaciones Microbiológicas-UR (GIMUR), Departamento de Biología, Facultad de Ciencias Naturales y Matemáticas, Universidad del Rosario, Bogotá, Colombia.
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12
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Williamson CHD, Stone NE, Nunnally AE, Hornstra HM, Wagner DM, Roe CC, Vazquez AJ, Nandurkar N, Vinocur J, Terriquez J, Gillece J, Travis J, Lemmer D, Keim P, Sahl JW. A global to local genomics analysis of Clostridioides difficile ST1/RT027 identifies cryptic transmission events in a northern Arizona healthcare network. Microb Genom 2019; 5:e000271. [PMID: 31107202 PMCID: PMC6700662 DOI: 10.1099/mgen.0.000271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 04/04/2019] [Indexed: 12/15/2022] Open
Abstract
Clostridioides difficile is a ubiquitous, diarrhoeagenic pathogen often associated with healthcare-acquired infections that can cause a range of symptoms from mild, self-limiting disease to toxic megacolon and death. Since the early 2000s, a large proportion of C. difficile cases have been attributed to the ribotype 027 (RT027) lineage, which is associated with sequence type 1 (ST1) in the C. difficile multilocus sequence typing scheme. The spread of ST1 has been attributed, in part, to resistance to fluoroquinolones used to treat unrelated infections, which creates conditions ideal for C. difficile colonization and proliferation. In this study, we analysed 27 isolates from a healthcare network in northern Arizona, USA, and 1352 publicly available ST1 genomes to place locally sampled isolates into a global context. Whole genome, single nucleotide polymorphism analysis demonstrated that at least six separate introductions of ST1 were observed in healthcare facilities in northern Arizona over an 18-month sampling period. A reconstruction of transmission networks identified potential nosocomial transmission of isolates, which were only identified via whole genome sequence analysis. Antibiotic resistance heterogeneity was observed among ST1 genomes, including variability in resistance profiles among locally sampled ST1 isolates. To investigate why ST1 genomes are so common globally and in northern Arizona, we compared all high-quality C. difficile genomes and identified that ST1 genomes have gained and lost a number of genomic regions compared to all other C. difficile genomes; analyses of other toxigenic C. difficile sequence types demonstrate that this loss may be anomalous and could be related to niche specialization. These results suggest that a combination of antimicrobial resistance and gain and loss of specific genes may explain the prominent association of this sequence type with C. difficile infection cases worldwide. The degree of genetic variability in ST1 suggests that classifying all ST1 genomes into a quinolone-resistant hypervirulent clone category may not be appropriate. Whole genome sequencing of clinical C. difficile isolates provides a high-resolution surveillance strategy for monitoring persistence and transmission of C. difficile and for assessing the performance of infection prevention and control strategies.
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Affiliation(s)
| | - Nathan E. Stone
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Amalee E. Nunnally
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Heidie M. Hornstra
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - David M. Wagner
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Chandler C. Roe
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Adam J. Vazquez
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Nivedita Nandurkar
- Northern Arizona Healthcare, Flagstaff Medical Center, Flagstaff, AZ 86001, USA
| | - Jacob Vinocur
- Northern Arizona Healthcare, Flagstaff Medical Center, Flagstaff, AZ 86001, USA
| | - Joel Terriquez
- Northern Arizona Healthcare, Flagstaff Medical Center, Flagstaff, AZ 86001, USA
| | - John Gillece
- Translational Genomics Research Institute, Flagstaff, AZ 86001, USA
| | - Jason Travis
- Translational Genomics Research Institute, Flagstaff, AZ 86001, USA
| | - Darrin Lemmer
- Translational Genomics Research Institute, Flagstaff, AZ 86001, USA
| | - Paul Keim
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Jason W. Sahl
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ 86011, USA
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13
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Mechanisms of Bacterial Tolerance and Persistence in the Gastrointestinal and Respiratory Environments. Clin Microbiol Rev 2018; 31:31/4/e00023-18. [PMID: 30068737 DOI: 10.1128/cmr.00023-18] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Pathogens that infect the gastrointestinal and respiratory tracts are subjected to intense pressure due to the environmental conditions of the surroundings. This pressure has led to the development of mechanisms of bacterial tolerance or persistence which enable microorganisms to survive in these locations. In this review, we analyze the general stress response (RpoS mediated), reactive oxygen species (ROS) tolerance, energy metabolism, drug efflux pumps, SOS response, quorum sensing (QS) bacterial communication, (p)ppGpp signaling, and toxin-antitoxin (TA) systems of pathogens, such as Escherichia coli, Salmonella spp., Vibrio spp., Helicobacter spp., Campylobacter jejuni, Enterococcus spp., Shigella spp., Yersinia spp., and Clostridium difficile, all of which inhabit the gastrointestinal tract. The following respiratory tract pathogens are also considered: Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Burkholderia cenocepacia, and Mycobacterium tuberculosis Knowledge of the molecular mechanisms regulating the bacterial tolerance and persistence phenotypes is essential in the fight against multiresistant pathogens, as it will enable the identification of new targets for developing innovative anti-infective treatments.
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14
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Ngernsombat C, Sreesai S, Harnvoravongchai P, Chankhamhaengdecha S, Janvilisri T. CD2068 potentially mediates multidrug efflux in Clostridium difficile. Sci Rep 2017; 7:9982. [PMID: 28855575 PMCID: PMC5577244 DOI: 10.1038/s41598-017-10155-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 08/03/2017] [Indexed: 02/04/2023] Open
Abstract
Clostridium difficile is a major cause of antibiotic-associated diarrhea and the treatment thereof becomes more difficult owing to a rise of multidrug resistant strains. ATP-binding cassette (ABC) transporters are known to play a crucial role in the resistance to multiple antibiotics. In this study, the potential contribution of an ABC transporter in C. difficile multidrug resistance was investigated. The expression level of the cd2068 gene in C. difficile encoding an ABC transporter was up-regulated following the exposure to certain antibiotics compared to the control cells. Heterologous expression of CD2068 in Escherichia coli revealed that it mediated the efflux of fluorescent substrates and conferred resistance to multiple drugs. The CD2068-associated ATPase activity in membrane vesicles was also stimulated by various antibiotics. Furthermore, the insertional inactivation of the cd2068 gene in C. difficile led to a significant increase in susceptibility to antibiotics, which could be genetically complemented, supporting that CD2068 was directly associated to the drug resistance. These results demonstrate the potential role for the ABC transporter CD2068 in the resistance mechanism against multiple drugs in C. difficile.
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Affiliation(s)
- Chawalit Ngernsombat
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Suthasinee Sreesai
- Department of Biology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | - Phurt Harnvoravongchai
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand
| | | | - Tavan Janvilisri
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
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15
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Insights into drug resistance mechanisms in Clostridium difficile. Essays Biochem 2017; 61:81-88. [PMID: 28258232 DOI: 10.1042/ebc20160062] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/03/2017] [Accepted: 01/05/2017] [Indexed: 01/05/2023]
Abstract
The incidence of Clostridium difficile infection has been elevated and becoming common in hospitals worldwide. Although antibiotics usually serve as the primary treatment for bacterial infection including C. difficile infection, limitations and failures have been evident due to drug resistance. Antibiotic resistance in C. difficile has been recognized as one of the most important factors to promote the infection and increase the level of severity and the recurrence rate. Several outbreaks in many countries have been linked to the emergence of hypervirulent drug-resistant strains. This pathogen harbours various mechanisms against the actions of antibiotics. The present study highlights three main drug-resistant strategies in C. difficile including drug inactivation, target modification and efflux pump. Other mechanisms that potentially contribute to drug-resistant traits in this organism are also discussed.
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16
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Schindler BD, Kaatz GW. Multidrug efflux pumps of Gram-positive bacteria. Drug Resist Updat 2016; 27:1-13. [DOI: 10.1016/j.drup.2016.04.003] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/28/2016] [Accepted: 04/22/2016] [Indexed: 11/16/2022]
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17
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Baines SD, Wilcox MH. Antimicrobial Resistance and Reduced Susceptibility in Clostridium difficile: Potential Consequences for Induction, Treatment, and Recurrence of C. difficile Infection. Antibiotics (Basel) 2015; 4:267-98. [PMID: 27025625 PMCID: PMC4790285 DOI: 10.3390/antibiotics4030267] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 07/02/2015] [Accepted: 07/03/2015] [Indexed: 12/11/2022] Open
Abstract
Clostridium difficile infection (CDI) remains a substantial burden on healthcare systems and is likely to remain so given our reliance on antimicrobial therapies to treat bacterial infections, especially in an aging population in whom multiple co-morbidities are common. Antimicrobial agents are a key component in the aetiology of CDI, both in the establishment of the infection and also in its treatment. The purpose of this review is to summarise the role of antimicrobial agents in primary and recurrent CDI; assessing why certain antimicrobial classes may predispose to the induction of CDI according to a balance between antimicrobial activity against the gut microflora and C. difficile. Considering these aspects of CDI is important in both the prevention of the infection and in the development of new antimicrobial treatments.
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Affiliation(s)
- Simon D Baines
- Department of Biological and Environmental Sciences, School of Life and Medical Sciences, University of Hertfordshire, Hatfield AL10 9AB, UK.
| | - Mark H Wilcox
- Leeds Institute of Biomedical and Clinical Sciences, Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK.
- Department of Microbiology, Leeds Teaching Hospitals NHS Trust, The General Infirmary, Leeds LS1 3EX, UK.
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18
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Andersen JL, He GX, Kakarla P, K C R, Kumar S, Lakra WS, Mukherjee MM, Ranaweera I, Shrestha U, Tran T, Varela MF. Multidrug efflux pumps from Enterobacteriaceae, Vibrio cholerae and Staphylococcus aureus bacterial food pathogens. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:1487-547. [PMID: 25635914 PMCID: PMC4344678 DOI: 10.3390/ijerph120201487] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/15/2015] [Indexed: 02/07/2023]
Abstract
Foodborne illnesses caused by bacterial microorganisms are common worldwide and constitute a serious public health concern. In particular, microorganisms belonging to the Enterobacteriaceae and Vibrionaceae families of Gram-negative bacteria, and to the Staphylococcus genus of Gram-positive bacteria are important causative agents of food poisoning and infection in the gastrointestinal tract of humans. Recently, variants of these bacteria have developed resistance to medically important chemotherapeutic agents. Multidrug resistant Escherichia coli, Salmonella enterica, Vibrio cholerae, Enterobacter spp., and Staphylococcus aureus are becoming increasingly recalcitrant to clinical treatment in human patients. Of the various bacterial resistance mechanisms against antimicrobial agents, multidrug efflux pumps comprise a major cause of multiple drug resistance. These multidrug efflux pump systems reside in the biological membrane of the bacteria and actively extrude antimicrobial agents from bacterial cells. This review article summarizes the evolution of these bacterial drug efflux pump systems from a molecular biological standpoint and provides a framework for future work aimed at reducing the conditions that foster dissemination of these multidrug resistant causative agents through human populations.
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Affiliation(s)
- Jody L Andersen
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Gui-Xin He
- Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, Lowell, MA 01854, USA.
| | - Prathusha Kakarla
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Ranjana K C
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Sanath Kumar
- QC Laboratory, Harvest and Post-Harvest Technology Division, Central Institute of Fisheries Education (CIFE), Seven Bungalows, Versova, Andheri (W), Mumbai 400061, India.
| | - Wazir Singh Lakra
- QC Laboratory, Harvest and Post-Harvest Technology Division, Central Institute of Fisheries Education (CIFE), Seven Bungalows, Versova, Andheri (W), Mumbai 400061, India.
| | - Mun Mun Mukherjee
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Indrika Ranaweera
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Ugina Shrestha
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
| | - Thuy Tran
- Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, Lowell, MA 01854, USA.
| | - Manuel F Varela
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA.
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19
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Guérin F, Galimand M, Tuambilangana F, Courvalin P, Cattoir V. Overexpression of the novel MATE fluoroquinolone efflux pump FepA in Listeria monocytogenes is driven by inactivation of its local repressor FepR. PLoS One 2014; 9:e106340. [PMID: 25188450 PMCID: PMC4154695 DOI: 10.1371/journal.pone.0106340] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 07/28/2014] [Indexed: 02/05/2023] Open
Abstract
Whereas fluoroquinolone resistance mainly results from target modifications in gram-positive bacteria, it is primarily due to active efflux in Listeria monocytogenes. The aim of this study was to dissect a novel molecular mechanism of fluoroquinolone resistance in this important human pathogen. Isogenic L. monocytogenes clinical isolates BM4715 and BM4716, respectively susceptible and resistant to fluoroquinolones, were studied. MICs of norfloxacin and ciprofloxacin were determined in the presence or in the absence of reserpine (10 mg/L). Strain BM4715 was susceptible to norfloxacin (MIC, 4 mg/L) and ciprofloxacin (MIC, 0.5 mg/L) whereas BM4716 was highly resistant to both drugs (MICs 128 and 32 mg/L, respectively). Reserpine was responsible for a 16-fold decrease in both norfloxacin and ciprofloxacin MICs against BM4716 suggesting efflux associated resistance. Whole-genome sequencing of the strains followed by comparative genomic analysis revealed a single point mutation in the gene for a transcriptional regulator, designated fepR (for fluoroquinolone efflux protein regulator) belonging to the TetR family. The frame-shift mutation was responsible for the introduction of a premature stop codon resulting in an inactive truncated protein. Just downstream from fepR, the structural gene for an efflux pump of the MATE family (named FepA) was identified. Gene expression was quantified by qRT-PCR and demonstrated that fepA expression was more than 64-fold higher in BM4716 than in BM4715. The clean deletion of the fepR gene from BM4715 was responsible for an overexpression of fepA with resistance to norfloxacin and ciprofloxacin, confirming the role of FepR as a local repressor of fepA. In conclusion, we demonstrated that overexpression of the new MATE efflux pump FepA is responsible for fluoroquinolone resistance in L. monocytogenes and secondary to inactivation of the FepR repressor.
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Affiliation(s)
- François Guérin
- CHU de Caen, Service de Microbiologie, F-14033 Caen, France
- Université de Caen Basse-Normandie, EA4655 (équipe “Antibio-résistance”), F-14032 Caen, France
| | - Marc Galimand
- Institut Pasteur, Unité des Agents Antibactériens, Paris, France
| | | | | | - Vincent Cattoir
- CHU de Caen, Service de Microbiologie, F-14033 Caen, France
- Université de Caen Basse-Normandie, EA4655 (équipe “Antibio-résistance”), F-14032 Caen, France
- * E-mail:
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20
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Banchs C, Poulos S, Nimjareansuk WS, Joo YE, Faham S. Substrate binding to the multidrug transporter MepA. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2539-46. [PMID: 24967747 DOI: 10.1016/j.bbamem.2014.06.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 06/11/2014] [Accepted: 06/16/2014] [Indexed: 10/25/2022]
Abstract
MepA is a multidrug transporter from Staphylococcus aureus that confers multidrug resistance through the efflux of a wide array of hydrophobic substrates. To evaluate the ability of MepA to recognize different substrates, the dissociation constants for interactions between MepA and three of its substrates (acriflavine (Acr), rhodamine 6G (R6G), and ethidium (Et)) were measured. Given that MepA is purified in the presence of detergents and that its substrates are hydrophobic, we examined the effect of the detergent concentration on the dissociation constant. We demonstrate that all three substrates interact directly with the detergent micelles. Additionally, we find the detergent effect on the KD value to be highly substrate-dependent. The KD value for R6G is greatly influenced by the detergent, whereas the KD values for Acr and Et are only modestly affected. The effect of the inactive D183A mutant on binding was also evaluated. The D183A mutant shows lower affinity toward Acr and Et.
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Affiliation(s)
- Christian Banchs
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22903, United States
| | - Sandra Poulos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22903, United States
| | - Waroot S Nimjareansuk
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22903, United States
| | - Ye Eun Joo
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22903, United States
| | - Salem Faham
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22903, United States.
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21
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Lu M, Radchenko M, Symersky J, Nie R, Guo Y. Structural insights into H+-coupled multidrug extrusion by a MATE transporter. Nat Struct Mol Biol 2013; 20:1310-7. [PMID: 24141706 PMCID: PMC3825517 DOI: 10.1038/nsmb.2687] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 08/27/2013] [Indexed: 11/09/2022]
Abstract
Multidrug and toxic compound extrusion (MATE) transporters contribute to multidrug resistance by coupling the efflux of drugs to the influx of Na(+) or H(+). Known structures of Na(+)-coupled, extracellular-facing MATE transporters from the NorM subfamily revealed 12 membrane-spanning segments related by a quasi-two-fold rotational symmetry and a multidrug-binding cavity situated near the membrane surface. Here we report the crystal structure of an H(+)-coupled MATE transporter from Bacillus halodurans and the DinF subfamily at 3.2-Å resolution, unveiling a surprisingly asymmetric arrangement of 12 transmembrane helices. We also identified a membrane-embedded substrate-binding chamber by combining crystallographic and biochemical analyses. Our studies further suggested a direct competition between H(+) and substrate during DinF-mediated transport and implied how a MATE transporter alternates between its extracellular- and intracellular-facing conformations to propel multidrug extrusion. Collectively, our results demonstrated heretofore-unrecognized mechanistic diversity among MATE transporters.
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Affiliation(s)
- Min Lu
- Department of Biochemistry and Molecular Biology, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, USA
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22
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Characterization of the MSMEG_2631 gene (mmp) encoding a multidrug and toxic compound extrusion (MATE) family protein in Mycobacterium smegmatis and exploration of its polyspecific nature using biolog phenotype microarray. J Bacteriol 2013; 195:1610-21. [PMID: 23292779 DOI: 10.1128/jb.01724-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Mycobacterium, multidrug efflux pumps can be associated with intrinsic drug resistance. Comparison of putative mycobacterial transport genes revealed a single annotated open reading frame (ORF) for a multidrug and toxic compound extrusion (MATE) family efflux pump in all sequenced mycobacteria except Mycobacterium leprae. Since MATE efflux pumps function as multidrug efflux pumps by conferring resistance to structurally diverse antibiotics and DNA-damaging chemicals, we studied this gene (MSMEG_2631) in M. smegmatis mc(2)155 and determined that it encodes a MATE efflux system that contributes to intrinsic resistance of Mycobacterium. We propose that the MSMEG_2631 gene be named mmp, for mycobacterial MATE protein. Biolog Phenotype MicroArray data indicated that mmp deletion increased susceptibility for phleomycin, bleomycin, capreomycin, amikacin, kanamycin, cetylpyridinium chloride, and several sulfa drugs. MSMEG_2619 (efpA) and MSMEG_3563 mask the effect of mmp deletion due to overlapping efflux capabilities. We present evidence that mmp is a part of an MSMEG_2626-2628-2629-2630-2631 operon regulated by a strong constitutive promoter, initiated from a single transcription start site. All together, our results show that M. smegmatis constitutively encodes an Na(+)-dependent MATE multidrug efflux pump from mmp in an operon with putative genes encoding proteins for apparently unrelated functions.
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23
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He GX, Thorpe C, Walsh D, Crow R, Chen H, Kumar S, Varela MF. EmmdR, a new member of the MATE family of multidrug transporters, extrudes quinolones from Enterobacter cloacae. Arch Microbiol 2011; 193:759-65. [PMID: 21822795 DOI: 10.1007/s00203-011-0738-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 06/05/2011] [Accepted: 07/20/2011] [Indexed: 10/17/2022]
Abstract
We cloned a gene, ECL_03329, from the chromosome of Enterobacter cloacae ATCC13047, using a drug-hypersensitive Escherichia coli KAM32 cell as the host. We show here that this gene, designated as emmdR, is responsible for multidrug resistance in E. cloacae. E. coli KAM32 host cells containing the cloned emmdR gene (KAM32/pEMMDR28) showed decreased susceptibilities to benzalkonium chloride, norfloxacin, ciprofloxacin, levofloxacin, ethidium bromide, acriflavine, rhodamine6G, and trimethoprim. emmdR-deficient E. cloacae cells (EcΔemmdR) showed increased susceptibilities to several of the antimicrobial agents tested. EmmdR has twelve predicted transmembrane segments and some shared identity with members of the multidrug and toxic compound extrusion (MATE) family of transporters. Study of the antimicrobial agent efflux activities revealed that EmmdR is an H+-drug antiporter but not a Na+ driven efflux pump. These results indicate that EmmdR is responsible for multidrug resistance and pumps out quinolones from E. cloacae.
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Affiliation(s)
- Gui-Xin He
- Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, Lowell, MA 01854, USA.
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24
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Zharov IA, Gelfand MS, Kazakov AE. Regulation of multidrug resistance genes by transcription factors of the BltR subfamily. Mol Biol 2011. [DOI: 10.1134/s002689331103023x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Barabote RD, Thekkiniath J, Strauss RE, Vediyappan G, Fralick JA, San Francisco MJ. Xenobiotic efflux in bacteria and fungi: a genomics update. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2011; 77:237-306. [PMID: 21692371 DOI: 10.1002/9780470920541.ch6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ravi D Barabote
- Department of Plant Sciences, University of California, Davis, California, USA
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26
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Rafii F, Park M, Carman RJ. Characterization of an ATP-binding cassette from Clostridium perfringens with homology to an ABC transporter from Clostridium hathewayi. Anaerobe 2009; 15:116-21. [PMID: 19655423 DOI: 10.1016/j.anaerobe.2009.01.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A ciprofloxacin-resistant mutant of Clostridium perfringens, strain VPI-C, which had stable mutations in the topoisomerase genes, accumulated less norfloxacin and ethidium bromide than the wild type, strain VPI. Efflux pump inhibitors both increased the accumulation of ethidium bromide by cells of the mutant and enhanced their sensitivity to this toxic dye. Cloning a gene, which codes for a putative ABC transporter protein (NP_562422) of 527 amino acids, from the mutant strain VPI-C into the wild-type strain VPI not only reduced the accumulation of ethidium bromide by the recombinant strain but also reduced its sensitivity to norfloxacin and ciprofloxacin. Efflux pump inhibitors decreased the rate at which ethidium bromide was removed from the cells of the recombinant strain. It appears that the putative ABC transporter protein (NP_562422) may contribute to extrusion of drugs from C. perfringens.
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Affiliation(s)
- Fatemeh Rafii
- Division of Microbiology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA.
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27
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Abstract
Drug efflux pumps play a key role in drug resistance and also serve other functions in bacteria. There has been a growing list of multidrug and drug-specific efflux pumps characterized from bacteria of human, animal, plant and environmental origins. These pumps are mostly encoded on the chromosome, although they can also be plasmid-encoded. A previous article in this journal provided a comprehensive review regarding efflux-mediated drug resistance in bacteria. In the past 5 years, significant progress has been achieved in further understanding of drug resistance-related efflux transporters and this review focuses on the latest studies in this field since 2003. This has been demonstrated in multiple aspects that include but are not limited to: further molecular and biochemical characterization of the known drug efflux pumps and identification of novel drug efflux pumps; structural elucidation of the transport mechanisms of drug transporters; regulatory mechanisms of drug efflux pumps; determining the role of the drug efflux pumps in other functions such as stress responses, virulence and cell communication; and development of efflux pump inhibitors. Overall, the multifaceted implications of drug efflux transporters warrant novel strategies to combat multidrug resistance in bacteria.
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Affiliation(s)
- Xian-Zhi Li
- Human Safety Division, Veterinary Drugs Directorate, Health Products and Food Branch, Health Canada, Ottawa, Ontario K1A OK9, Canada
| | - Hiroshi Nikaido
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720-3202, USA
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Kuroda T, Tsuchiya T. Multidrug efflux transporters in the MATE family. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1794:763-8. [PMID: 19100867 DOI: 10.1016/j.bbapap.2008.11.012] [Citation(s) in RCA: 234] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2008] [Revised: 11/14/2008] [Accepted: 11/17/2008] [Indexed: 10/21/2022]
Abstract
The MATE (Multidrug And Toxic Compound Extrusion) family is the most recently categorized one among five multidrug efflux transporter families. As far as we know, about twenty MATE transporters have been characterized so far. According to the information in sequence databases, huge numbers of MATE transporters seem to be present in various microorganisms. In this review, we would like to summarize the properties of the MATE-family transporters.
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Affiliation(s)
- Teruo Kuroda
- Department of Genome Applied Microbiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan
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Effects of exposure of Clostridium difficile PCR ribotypes 027 and 001 to fluoroquinolones in a human gut model. Antimicrob Agents Chemother 2008; 53:412-20. [PMID: 18710908 DOI: 10.1128/aac.00306-08] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The incidence of Clostridium difficile infection is increasing, with reports implicating fluoroquinolone use. A three-stage chemostat gut model was used to study the effects of three fluoroquinolones (ciprofloxacin, levofloxacin, and moxifloxacin) on the gut microbiota and two epidemic C. difficile strains, strains of PCR ribotypes 027 and 001, in separate experiments. C. difficile total viable counts, spore counts, and cytotoxin titers were determined. The emergence of C. difficile isolates with reduced antibiotic susceptibility was monitored with fluoroquinolone-containing medium, and molecular analysis of the quinolone resistance-determining region was performed. C. difficile spores were quiescent in the absence of fluoroquinolones. Instillation of each fluoroquinolone led to C. difficile spore germination and high-level cytotoxin production. High-level toxin production occurred after detectable spore germination in all experiments except those with C. difficile PCR ribotype 027 and moxifloxacin, in which marked cytotoxin production preceded detectable germination, which coincided with isolate recovery on fluoroquinolone-containing medium. Three C. difficile PCR ribotype 027 isolates and one C. difficile PCR ribotype 001 isolate from fluoroquinolone-containing medium exhibited elevated MICs (80 to > or =180 mg/liter) and possessed mutations in gyrA or gyrB. These in vitro results suggest that all fluoroquinolones have the propensity to induce C. difficile infection, regardless of their antianaerobe activities. Resistant mutants were seen only following moxifloxacin exposure.
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Detection and characterization of an ABC transporter in Clostridium hathewayi. Arch Microbiol 2008; 190:417-26. [PMID: 18504552 DOI: 10.1007/s00203-008-0385-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 04/30/2008] [Accepted: 05/05/2008] [Indexed: 10/22/2022]
Abstract
An ABC transporter gene from Clostridium hathewayi is characterized. It has duplicated ATPase domains in addition to a transmembrane protein. Its deduced amino acid sequence has conserved functional domains with ATPase components of the multidrug efflux pump genes of several bacteria. Cloning this transporter gene into C. perfringens and E. coli resulted in decreased sensitivities of these bacteria to fluoroquinolones. It also decreased the accumulation and increased the efflux of ethidium bromide from cells containing the cloned gene. Carbonyl cyanide-m-chlorophenylhydrazone (CCCP) inhibited both accumulation and efflux of ethidium bromide from these cells. The ATPase mRNA was overexpressed in the fluoroquinolone-resistant strain when exposed to ciprofloxacin. This is the first report of an ABC transporter in C. hathewayi.
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Shahverdi A, Monsef-Esfahani H, Tavasoli F, Zaheri A, Mirjani R. Trans-Cinnamaldehyde from Cinnamomum zeylanicum Bark Essential Oil Reduces the Clindamycin Resistance of Clostridium difficile in vitro. J Food Sci 2007; 72:S055-8. [DOI: 10.1111/j.1750-3841.2006.00204.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Omote H, Hiasa M, Matsumoto T, Otsuka M, Moriyama Y. The MATE proteins as fundamental transporters of metabolic and xenobiotic organic cations. Trends Pharmacol Sci 2006; 27:587-93. [PMID: 16996621 DOI: 10.1016/j.tips.2006.09.001] [Citation(s) in RCA: 323] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Revised: 08/09/2006] [Accepted: 09/08/2006] [Indexed: 01/11/2023]
Abstract
Multidrug and toxic compound extrusion (MATE) proteins, comprising the most recently designated family of multidrug transporter proteins, are widely distributed in all kingdoms of living organisms, although their function is far from understood. The bacterial MATE-type transporters that have been characterized function as exporters of cationic drugs, such as norfloxacin and ethidium, through H(+) or Na(+) exchange. Plant MATE-type transporters are involved in the detoxification of secondary metabolites, including alkaloids. Mammalian MATE-type transporters are responsible for the final step in the excretion of metabolic waste and xenobiotic organic cations in the kidney and liver through electroneutral exchange of H(+). Thus, we propose that members of the MATE family are organic cation exporters that excrete metabolic or xenobiotic organic cations from the body.
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Affiliation(s)
- Hiroshi Omote
- Laboratory of Membrane Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8530, Japan
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Rafii F, Park M. Substitutions of amino acids in alpha-helix-4 of gyrase A confer fluoroquinolone resistance on Clostridium perfringens. Arch Microbiol 2006; 187:137-44. [PMID: 17051403 DOI: 10.1007/s00203-006-0180-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Revised: 08/30/2006] [Accepted: 09/12/2006] [Indexed: 11/28/2022]
Abstract
DNA gyrase, an essential enzyme that regulates DNA topology in bacteria, is the target of fluoroquinolones. Three fluoroquinolone-resistant mutants derived from one strain of Clostridium perfringens had amino acid substitutions of glycine 81 to cysteine, aspartic acid 87 to tyrosine, or both, in alpha-helix-4 of gyrase A. The gyrase mutations affected the growth kinetics of mutants differently when the mutants were exposed to increasing concentrations of gatifloxacin and ciprofloxacin. Fluoroquinolone concentration-dependent effects observed during growth in the exponential and stationary phases depended on the presence of particular gyrA mutations. Introduction of a wild-type gyrA gene into the mutants enhanced their susceptibility to fluoroquinolones and decreased their growth rates proportional to increases in fluoroquinolone concentrations. Amino acid substitutions in alpha-helix-4 of gyrase A protected C. perfringens from fluoroquinolones, and a strain with two substitutions was the most resistant.
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Affiliation(s)
- Fatemeh Rafii
- Division of Microbiology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA.
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Kaatz GW, McAleese F, Seo SM. Multidrug resistance in Staphylococcus aureus due to overexpression of a novel multidrug and toxin extrusion (MATE) transport protein. Antimicrob Agents Chemother 2005; 49:1857-64. [PMID: 15855507 PMCID: PMC1087643 DOI: 10.1128/aac.49.5.1857-1864.2005] [Citation(s) in RCA: 189] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Efflux is an important mechanism of multidrug resistance (MDR) in bacteria. The multidrug and toxin extrusion (MATE) family is the most recently described group of MDR efflux proteins, none of which have previously been identified in Staphylococcus aureus. Two independently derived S. aureus mutants having efflux-related MDR phenotypes were studied using microarray technology and a marked overexpression of an open reading frame (ORF; mepA) encoding a protein homologous with MATE family proteins was observed in both. There was concomitant overexpression of ORFs in close proximity to mepA (approximately 100 bp) encoding a MarR-type regulator (mepR, upstream of mepA) and a protein of unknown function (mepB, downstream). Experiments in which mepA was overexpressed or disrupted revealed that the encoded protein has a broad substrate profile that includes several monovalent and divalent biocides and the fluoroquinolone antimicrobial agents norfloxacin and ciprofloxacin. The function of MepB is obscure, it does not contribute to the MDR phenotype conferred by MepA. MepR overexpression reversed the MDR phenotypes of both mutants by repressing mepA transcription. All three ORFs are preferentially transcribed as a single mepRAB unit, suggesting that the three genes form an operon.
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Affiliation(s)
- Glenn W Kaatz
- The John D. Dingell Department of Veteran's Affairs Medical Center, Detroit, MI 48201, USA.
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Abstract
Antibiotic resistance continues to plague antimicrobial chemotherapy of infectious disease. And while true biocide resistance is as yet unrealized, in vitro and in vivo episodes of reduced biocide susceptibility are common and the history of antibiotic resistance should not be ignored in the development and use of biocidal agents. Efflux mechanisms of resistance, both drug specific and multidrug, are important determinants of intrinsic and/or acquired resistance to these antimicrobials, with some accommodating both antibiotics and biocides. This latter raises the spectre (as yet generally unrealized) of biocide selection of multiple antibiotic-resistant organisms. Multidrug efflux mechanisms are broadly conserved in bacteria, are almost invariably chromosome-encoded and their expression in many instances results from mutations in regulatory genes. In contrast, drug-specific efflux mechanisms are generally encoded by plasmids and/or other mobile genetic elements (transposons, integrons) that carry additional resistance genes, and so their ready acquisition is compounded by their association with multidrug resistance. While there is some support for the latter efflux systems arising from efflux determinants of self-protection in antibiotic-producing Streptomyces spp. and, thus, intended as drug exporters, increasingly, chromosomal multidrug efflux determinants, at least in Gram-negative bacteria, appear not to be intended as drug exporters but as exporters with, perhaps, a variety of other roles in bacterial cells. Still, given the clinical significance of multidrug (and drug-specific) exporters, efflux must be considered in formulating strategies/approaches to treating drug-resistant infections, both in the development of new agents, for example, less impacted by efflux and in targeting efflux directly with efflux inhibitors.
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Affiliation(s)
- Keith Poole
- Department of Microbiology & Immunology, Queen's University, Kingston, ON, Canada.
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