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Qi Q, Ghaly TM, Rajabal V, Russell DH, Gillings MR, Tetu SG. Vegetable phylloplane microbiomes harbour class 1 integrons in novel bacterial hosts and drive the spread of chlorite resistance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 954:176348. [PMID: 39304140 DOI: 10.1016/j.scitotenv.2024.176348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2024] [Revised: 09/10/2024] [Accepted: 09/15/2024] [Indexed: 09/22/2024]
Abstract
Bacterial hosts in vegetable phylloplanes carry mobile genetic elements, such as plasmids and transposons that are associated with integrons. These mobile genetic elements and their cargo genes can enter human microbiomes via consumption of fresh agricultural produce, including uncooked vegetables. This presents a risk of acquiring antimicrobial resistance genes from uncooked vegetables. To better understand horizontal gene transfer of class 1 integrons in these compartments, we applied epicPCR, a single-cell fusion-PCR surveillance technique, to link the class 1 integron integrase (intI1) gene with phylogenetic markers of their bacterial hosts. Ready-to-eat salads carried class 1 integrons from the phyla Bacteroidota and Pseudomonadota, including four novel genera that were previously not known to be associated with intI1. We whole-genome sequenced Pseudomonas and Erwinia hosts of pre-clinical class 1 integrons that are embedded in Tn402-like transposons. The proximal gene cassette in these integrons was identified as a chlorite dismutase gene cassette, which we showed experimentally to confer chlorite resistance. Chlorine-derived compounds such as acidified sodium chlorite and chloride dioxide are used to disinfectant raw vegetables in food processing facilities, suggesting selection for chlorite resistance in phylloplane integrons. The spread of integrons conferring chlorite resistance has the potential to exacerbate integron-mediated antimicrobial resistance (AMR) via co-selection of chlorite resistance and AMR, thus highlighting the importance of monitoring chlorite residues in agricultural produce. These results demonstrate the strength of combining epicPCR and culture-based isolation approaches for identifying hosts and dissecting the molecular ecology of class 1 integrons.
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Affiliation(s)
- Qin Qi
- School of Natural Sciences, Macquarie University, New South Wales, Australia; Manchester Institute of Biotechnology, The University of Manchester, Greater Manchester, United Kingdom.
| | - Timothy M Ghaly
- School of Natural Sciences, Macquarie University, New South Wales, Australia
| | - Vaheesan Rajabal
- School of Natural Sciences, Macquarie University, New South Wales, Australia; ARC Centre of Excellence for Synthetic Biology, Macquarie University, New South Wales, Australia
| | - Dylan H Russell
- School of Natural Sciences, Macquarie University, New South Wales, Australia
| | - Michael R Gillings
- School of Natural Sciences, Macquarie University, New South Wales, Australia
| | - Sasha G Tetu
- School of Natural Sciences, Macquarie University, New South Wales, Australia; ARC Centre of Excellence for Synthetic Biology, Macquarie University, New South Wales, Australia.
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Li S, Jiang X, Li C, Ju Y, Yue L, Chen F, Hu L, Wang J, Hu X, Tuohetaerbaike B, Wen H, Zhang W, Zhou D, Yin Z, Chen F. A blaSIM-1 and mcr-9.2 harboring Klebsiella michiganensis strain reported and genomic characteristics of Klebsiella michiganensis. Front Cell Infect Microbiol 2022; 12:973901. [PMID: 36093205 PMCID: PMC9448873 DOI: 10.3389/fcimb.2022.973901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
As a newly emerging Klebsiella pathogen, more and more Klebsiella michiganensis drug resistant strains have been reported in recent years, which posed serious threats to public health. Here we first reported a multidrug-resistant K. michiganensis strain 12084 with two blaSIM-1 and one mcr-9.2 genes isolated from the sputum specimen of a patient in the Second Affiliated Hospital of Zhejiang University School of Medicine and analyzed its genetic basis and drug-resistance phenotypes. Genetic analysis showed that this strain harbored three different incompatibility groups (IncHI2, IncHI5, and IncFIIpKPHS2:IncFIB-4.1) of plasmids (p12084-HI2, p12084-HI5, and p12084-FII). A total of 26 drug-resistance genes belonging to 12 classes of antibiotics were identified, most of which (24) were located on two plasmids (p12084-HI2 and p12084-HI5). Interestingly, two blaSIM-1 genes were identified to locate on p12084-HI2 and p12084-HI5, respectively, both of which were embedded in In630, indicating their genetic homogeny. It was noting that one blaSIM-1 gene was situated in a novel unit transposon (referred to as Tn6733) on the p12084-HI5 plasmid. We also discovered an mcr-9.2 gene on the p12084-HI2 plasmid. To the best of our knowledge, this is the first report of a blaSIM-1 and mcr-9.2 harboring K. michiganensis strain. We then investigated the population structure/classification, and antibiotic resistance for all 275 availably global K. michiganensis genomes. Population structure revealed that K. michiganensis could be divided into two main clades (Clade 1 and Clade 2); the most popular ST29 was located in Clade 1, while other common STs (such as ST50, ST27, and ST43) were located in Clade 2. Drug-resistance analysis showed 25.5% of the K. michiganensis strains (70/275) harboring at least one carbapenemase gene, indicating severe drug resistance of K. michiganensis beyond our imagination; this is a dangerous trend and should be closely monitored, especially for ST27 K. michiganensis with the most drug-resistant genes among all the STs. Overall, we reported a blaSIM-1 and mcr-9.2 harboring K. michiganensis strain, and further revealed the population structure/classification, and drug-resistance of K. michiganensis, which provided an important framework, reference, and improved understanding of K. michiganensis.
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Affiliation(s)
- Shuangshuang Li
- Chinese Academy of Sciences (CAS) Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoyuan Jiang
- Chinese Academy of Sciences (CAS) Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
| | - Cuidan Li
- Chinese Academy of Sciences (CAS) Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
| | - Yingjiao Ju
- Chinese Academy of Sciences (CAS) Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Liya Yue
- Chinese Academy of Sciences (CAS) Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
| | - Fangzhou Chen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Lingfei Hu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Jing Wang
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- Department of Respiratory Medicine, Second Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Xin Hu
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Bahetibieke Tuohetaerbaike
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Hao Wen
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Wenbao Zhang
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Dongsheng Zhou
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Zhe Yin
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- *Correspondence: Zhe Yin, ; Fei Chen,
| | - Fei Chen
- Chinese Academy of Sciences (CAS) Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences and China National Center for Bioinformation, Beijing, China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Pathogenesis, Prevention and Treatment of High Incidence Diseases in Central Asia, Department of Respiratory Medicine, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- *Correspondence: Zhe Yin, ; Fei Chen,
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Zhou W, Zhang E, Zhou J, He Z, Zhou Y, Han J, Qu D. Characterization and Comparative Genomics Analysis of lncFII Multi-Resistance Plasmids Carrying bla CTX - M and Type1 Integrons From Escherichia coli. Front Microbiol 2021; 12:753979. [PMID: 34867876 PMCID: PMC8637017 DOI: 10.3389/fmicb.2021.753979] [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] [Accepted: 10/29/2021] [Indexed: 11/25/2022] Open
Abstract
This research aimed to investigate the presence and transferability of the extended-spectrum β-lactamase resistance genes to identify the genetic context of multi-drug resistant (MDR) loci in two Escherichia coli plasmids from livestock and poultry breeding environment. MICs were determined by broth microdilution. A total of 137 E. coli resistant to extended-spectrum β-lactam antibiotics were screened for the presence of the ESBL genes by PCR. Only two E. coli out of 206 strains produced carbapenemases, including strain 11011 that produced enzyme A, and strain 417957 that produced enzyme B. The genes were blaKPC and blaNDM, respectively. The plasmids containing blaCTX–M were conjugatable, and the plasmids containing carbapenem resistance gene were not conjugatable. Six extended-spectrum β-lactamase resistance genes were detected in this research, including blaTEM, blaCTX–M, blaSHV, blaOAX–1, blaKPC, and blaNDM, and the detection rates were 94.89% (130/137), 92.7% (127/137), 24.81% (34/137), 20.43% (28/137), 0.72% (1/137), and 0.72% (1/137), respectively. Two conjugative lncFII multi-resistance plasmids carrying blaCTX–M, p11011-fosA and p417957-CTXM, were sequenced and analyzed. Both conjugative plasmids were larger than 100 kb and contained three accessory modules, including MDR region. The MDR region of the two plasmids contained many antibiotic resistance genes, including blaCTX–M, mph (A), dfrA17, aadA5, sul1, etc. After transfer, both the transconjugants displayed elevated MICs of the respective antimicrobial agents. A large number of resistance genes clusters in specific regions may contribute to the MDR profile of the strains. The presence of mobile genetic elements at the boundaries can possibly facilitate transfer among Enterobacteriaceae through inter-replicon gene transfer. Our study provides beta-lactam resistance profile of bacteria, reveals the prevalence of β-lactamase resistance genes in livestock and poultry breeding environment in Zhejiang Province, and enriches the research on IncFII plasmids containing blaCTX–M.
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Affiliation(s)
- Wei Zhou
- Zhejiang Provincial Center for Animal Disease Prevention and Control, Hangzhou, China
| | - Enbao Zhang
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Jinzhi Zhou
- Zhejiang Provincial Center for Animal Disease Prevention and Control, Hangzhou, China
| | - Ze He
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Yuqiao Zhou
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Jianzhong Han
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Daofeng Qu
- Key Laboratory of Food Quality and Safety, School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
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Carbapenem Resistance Determinants Acquired through Novel Chromosomal Integrations in Extensively Drug-Resistant Pseudomonas aeruginosa. Antimicrob Agents Chemother 2021; 65:e0028921. [PMID: 33941520 PMCID: PMC8373256 DOI: 10.1128/aac.00289-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Two novel blaDIM-1- or blaIMP-1-containing genomic islands (GIs) were discovered by whole-genome sequence analyses in four extensively drug-resistant (XDR) Pseudomonas aeruginosa isolates from inpatients at a tertiary hospital in Ghana. The strains were of sequence type 234 (ST234) and formed a phylogenetic clade together with ST111, which is recognized as a global high-risk clone. Their carbapenem resistance was encoded by two Tn402-type integrons, In1592 (blaDIM-1) and In1595 (blaIMP-1), both carrying complete tni mobilization modules. In1595 was bound by conserved 25-bp inverted repeats (IRs) flanked by 5-bp direct repeats (DRs) associated with target site duplication. The integrons were embedded in two GIs that contained cognate integrases and were distinguished by a lower GC content than the chromosomal average. PAGI-97A (52.659 bp; In1592), which encoded a P4-type site-specific integrase of the tyrosine recombinase family in its 3′ border, was integrated into tRNA-Pro(ggg) and bracketed by a 49-bp perfect DR created by 3′-end target duplication. GIs with the same structural features, but diverse genetic content, were identified in 41/226 completed P. aeruginosa genomes. PAGI-97B (22,636 bp; In1595), which encoded an XerC/D superfamily integrase in its 5′ border, was inserted into the small RNA (sRNA) PrrF1/PrrF2 locus. Specific insertions into this highly conserved locus involved in iron-dependent regulation, all leaving PrrF1 intact, were identified in an additional six phylogenetically unrelated P. aeruginosa genomes. Our molecular analyses unveiled a hospital-associated clonal dissemination of carbapenem-resistant ST234 P. aeruginosa in which the XDR phenotype resulted from novel insertions of two GIs into specific chromosomal sites.
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Jahan MI, Rahaman MM, Hossain MA, Sultana M. Occurrence of intI1-associated VIM-5 carbapenemase and co-existence of all four classes of β-lactamase in carbapenem-resistant clinical Pseudomonas aeruginosa DMC-27b. J Antimicrob Chemother 2021; 75:86-91. [PMID: 31647552 DOI: 10.1093/jac/dkz426] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/25/2019] [Accepted: 09/13/2019] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Emergence of carbapenem-resistant Pseudomonas aeruginosa is limiting current treatment options. Carbapenemases and their association with integrons can cause rapid dissemination of resistance traits. We report here the co-existence and chromosomal inheritance of all four classes of β-lactamase and the presence of a unique class 1 integron (intI1) harbouring blaVIM-5 within a single isolate of P. aeruginosa, DMC-27b. METHODS DMC-27b, isolated from urine, was characterized for carbapenem resistance both phenotypically and genotypically. The orientation of gene cassette structures of class 1 integrons was determined using referenced and designed overlapping primers and complete genome sequence (CGS) data. The antimicrobial resistance profile, porin protein mutations and the presence of active efflux activity were studied from the CGS. RESULTS P. aeruginosa DMC-27b was resistant to a total of 20 antibiotics, with imipenem and meropenem MIC90s of >512 mg/L. The isolate harboured all four classes of β-lactamase: VEB-1 (class A), VIM-5 (class B), PDC-35 (class C) and OXA-2 and OXA-50 (both class D). Chromosomal harbouring of blaVIM-5 was associated with the intI1 gene cassette as the sole gene, a unique cassette so far reported. A total of 11 mutations, among them some mutations causing extra folds and changes in binding sites, in porin protein OprD might also affect its functionality regarding the transportation of antibiotics. CONCLUSIONS This is one of the earliest reports of its kind on the co-existence of all four β-lactamase classes in P. aeruginosa DMC-27b. Acquisition of multiple resistance determinants is paving the way for the development of MDR. This superbug is a model for rapid dissemination of resistance traits both horizontally and vertically.
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Affiliation(s)
- M Ishrat Jahan
- Department of Microbiology, University of Dhaka, Dhaka-1000, Bangladesh
| | - M Mizanur Rahaman
- Department of Microbiology, University of Dhaka, Dhaka-1000, Bangladesh
| | - M Anwar Hossain
- Department of Microbiology, University of Dhaka, Dhaka-1000, Bangladesh
| | - Munawar Sultana
- Department of Microbiology, University of Dhaka, Dhaka-1000, Bangladesh
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6
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Ghaly TM, Paulsen IT, Sajjad A, Tetu SG, Gillings MR. A Novel Family of Acinetobacter Mega-Plasmids Are Disseminating Multi-Drug Resistance Across the Globe While Acquiring Location-Specific Accessory Genes. Front Microbiol 2020; 11:605952. [PMID: 33343549 PMCID: PMC7738440 DOI: 10.3389/fmicb.2020.605952] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 11/10/2020] [Indexed: 11/13/2022] Open
Abstract
Acinetobacter species are emerging as major nosocomial pathogens, aided by their ability to acquire resistance to all classes of antibiotics. A key factor leading to their multi-drug resistance phenotypes is the acquisition of a wide variety of mobile genetic elements, particularly large conjugative plasmids. Here, we characterize a family of 21 multi-drug resistance mega-plasmids in 11 different Acinetobacter species isolated from various locations across the globe. The plasmid family exhibits a highly dynamic and diverse accessory genome, including 221 antibiotic resistance genes (ARGs) that confer resistance to 13 classes of antibiotics. We show that plasmids isolated within the same geographic region are often evolutionarily divergent members of this family based on their core-genome, yet they exhibit a more similar accessory genome. Individual plasmids, therefore, can disseminate to different locations around the globe, where they then appear to acquire diverse sets of accessory genes from their local surroundings. Further, we show that plasmids from several geographic regions were enriched with location-specific functional traits. Together, our findings show that these mega-plasmids can transmit across species boundaries, have the capacity for global dissemination, can accumulate a diverse suite of location-specific accessory genes, and can confer multi-drug resistance phenotypes of significant concern for human health. We therefore highlight this previously undescribed plasmid family as a serious threat to healthcare systems worldwide. These findings also add to the growing concern that mega-plasmids are key disseminators of antibiotic resistance and require global surveillance.
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Affiliation(s)
- Timothy M. Ghaly
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Ian T. Paulsen
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW, Australia
| | - Ammara Sajjad
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
| | - Sasha G. Tetu
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW, Australia
| | - Michael R. Gillings
- Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW, Australia
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7
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Wang L, Fu L, Liu Z, Guo H, Wang L, Feng M, He Y, Chen Q, Hu J. Comparative Analysis of Antimicrobial Resistance, Integrons, and Virulence Genes Among Extended-Spectrum β-Lactamase-Positive Laribacter hongkongensis from Edible Frogs and Freshwater Fish. Microb Drug Resist 2019; 25:855-864. [PMID: 30767721 DOI: 10.1089/mdr.2018.0366] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Aquatic animals are now recognized to be major hosts of potentially pathogenic Laribacter hongkongensis. A comparative study was carried out among extended-spectrum β-lactamase (ESBL)-producing L. hongkongensis isolated from frogs (47 isolates) and fish (41 isolates) to examine phenotypic and genotypic antimicrobial resistance profiles, integrons, virulence factors, and genetic relatedness. Isolates from frogs showed a higher incidence of antibiotic resistance compared with those from fish for most of the antimicrobials tested, especially trimethoprim-sulfamethoxazole, tetracycline, ciprofloxacin, levofloxacin, and streptomycin. Multidrug-resistant strains were also found more frequently among frog isolates (5.44 traits on average) than among fish isolates (3.29 traits). In frog isolates, class 1 integrons and the resistance genes sul1, sul2, tetA, tetR, and aac(6')-Ib-cr showed a clearly higher incidence compared with isolates from fish. In contrast, blaTEM-1 was higher in fish isolates than in frog isolates. Correlation analysis showed that sul1, sul2, tetA, and tetR were significantly associated with class 1 integrons in frog isolates. The correlations indicated a potential co-selection risk of bacterial resistance to antibiotics. In addition, the distribution of three virulence-associated determinants for the type IV bundle-forming pili gene (bfpA), ferric aerobactin receptor gene (iucD), and iron-responsive element gene (ireA) was markedly higher in strains isolated from frogs than in those isolated from fish. No obvious genetic relatedness was observed between both populations. The large differences found in the incidence of antibiotic resistance, integrons along with the multiple resistance genes, virulence factors, and genetic fingerprints determined by pulsed-field gel electrophoresis suggest a high degree of antibiotic resistance and pathogenicity potential of ESBL-producing L. hongkongensis from isolates found in frogs.
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Affiliation(s)
- Ling Wang
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Leiwen Fu
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Zhihua Liu
- 2 Department of Infectious Disease, Nanfang Hospital, Guangzhou, China
| | - Huijie Guo
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Li Wang
- 3 Maternal and Child Health Hospital of Longgang, Shenzhen, China
| | - Mei Feng
- 4 Center for Disease Control and Prevention of Shunde, Foshan, China
| | - Yaqing He
- 5 Center for Disease Control and Prevention of Shenzhen, Shenzhen, China
| | - Qing Chen
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jing Hu
- 1 Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China.,6 Department of Nosocomial Infection Administration, Zhujiang Hospital, Southern Medical University, Guangzhou, China
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Impact of Wastewater Treatment on the Prevalence of Integrons and the Genetic Diversity of Integron Gene Cassettes. Appl Environ Microbiol 2018; 84:AEM.02766-17. [PMID: 29475864 DOI: 10.1128/aem.02766-17] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/10/2018] [Indexed: 12/23/2022] Open
Abstract
The integron platform allows the acquisition, expression, and dissemination of antibiotic resistance genes within gene cassettes. Wastewater treatment plants (WWTPs) contain abundant resistance genes; however, knowledge about the impacts of wastewater treatment on integrons and their gene cassettes is limited. In this study, by using clone library analysis and high-throughput sequencing, we investigated the abundance of class 1, 2, and 3 integrons and their corresponding gene cassettes in three urban WWTPs. Our results showed that class 1 integrons were most abundant in WWTPs and that wastewater treatment significantly reduced the abundance of all integrons. The WWTP influents harbored the highest diversity of class 1 integron gene cassettes, whereas class 3 integron gene cassettes exhibited highest diversity in activated sludge. Most of the gene cassette arrays detected in class 1 integrons were novel. Aminoglycoside, beta-lactam, and trimethoprim resistance genes were highly prevalent in class 1 integron gene cassettes, while class 3 integrons mainly carried beta-lactam resistance gene cassettes. A core class 1 integron resistance gene cassette pool persisted during wastewater treatment, implying that these resistance genes could have high potential to spread into environments through WWTPs. These data provide new insights into the impact of wastewater treatment on integron pools and highlight the need for surveillance of resistance genes within both class 1 and 3 integrons.IMPORTANCE Wastewater treatment plants represent a significant sink and transport medium for antibiotic resistance bacteria and genes spreading into environments. Integrons are important genetic elements involved in the evolution of antibiotic resistance. To better understand the impact of wastewater treatment on integrons and their gene cassette contexts, we conducted clone library construction and high-throughput sequencing to analyze gene cassette contexts for class 1 and class 3 integrons during the wastewater treatment process. This study comprehensively profiled the distribution of integrons and their gene cassettes (especially class 3 integrons) in influents, activated sludge, and effluents of conventional municipal wastewater treatment plants. We further demonstrated that while wastewater treatment significantly reduced the abundance of integrons and the diversity of associated gene cassettes, a large fraction of integrons persisted in wastewater effluents and were consequentially discharged into downstream natural environments.
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DI H, Liang S, Li Q, Shi L, Shima A, Meng H, Yan H, Yamasaki S. Providencia in retail meats from Guangzhou, China and Osaka, Japan: prevalence, antimicrobial resistance and characterization of classes 1, 2 and 3 integrons. J Vet Med Sci 2018; 80:829-835. [PMID: 29553069 PMCID: PMC5989031 DOI: 10.1292/jvms.18-0037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bacteria of the genus Providencia are opportunistic pathogens of clinical significance due to their association with diarrhea and urinary tract infections. The present
study was conducted to examine the prevalence and antimicrobial resistance of Providencia spp. in retail meats sold in Guangzhou, China and Osaka, Japan. Out of 158 meat
samples including beef, pork and chicken, 67 Providencia (42%) belonging to four species viz., P. alcalifaciens, P.
rustigianii, P. stuartii and P. rettgeri were isolated, and most of them were resistant to tetracycline (91%) followed by ampicillin
(69%) and streptomycin (49%). Of 67 isolates, 29 (43%) were MDR, which is defined to be resistant to more than three classes of antimicrobials. No statistically significant differences were
observed between Chinese and Japanese retail meat samples regarding contamination rate of Providencia spp. as well as frequency of the antimicrobial resistance of the
isolates including MDR. Class 1 and/or class 2 integrons were detected in six of the eight isolates that were resistant to more than 4 antimicrobials, however none of the isolates harbored
class 3 integron. A P. rustigianii harboring the blaOXA-10 gene was isolated, which is the first report of Providencia with
blaOXA-10 gene of food origin. These data suggest that retail meats in China and Japan are substantially contaminated with Providencia spp.,
which displayed a high frequency of antimicrobial resistance, and establishing the surveillance of Providencia spp., especially antimicrobial resistant one, in retail meats
is imperative.
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Affiliation(s)
- Huiling DI
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China.,Research Institute of Food Safety and Nutrition, Jinan University, Guangzhou 510632, China.,Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Sisi Liang
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Qingyang Li
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Lei Shi
- Research Institute of Food Safety and Nutrition, Jinan University, Guangzhou 510632, China.,State Key Laboratory of Food Safety Technology for Meat Products, Xiamen Yinxiang Group Co., Ltd., Xiamen 361100, China
| | - Ayaka Shima
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Hecheng Meng
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - He Yan
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Shinji Yamasaki
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan
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Jones-Dias D, Manageiro V, Ferreira E, Barreiro P, Vieira L, Moura IB, Caniça M. Architecture of Class 1, 2, and 3 Integrons from Gram Negative Bacteria Recovered among Fruits and Vegetables. Front Microbiol 2016; 7:1400. [PMID: 27679611 PMCID: PMC5020092 DOI: 10.3389/fmicb.2016.01400] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 08/24/2016] [Indexed: 02/03/2023] Open
Abstract
The spread of antibiotic resistant bacteria throughout the food chain constitutes a public health concern. To understand the contribution of fresh produce in shaping antibiotic resistance bacteria and integron prevalence in the food chain, 333 antibiotic resistance Gram negative isolates were collected from organic and conventionally produced fruits (pears, apples, and strawberries) and vegetables (lettuces, tomatoes, and carrots). Although low levels of resistance have been detected, the bacterial genera identified in the assessed fresh produce are often described not only as environmental, but mostly as commensals and opportunistic pathogens. The genomic characterization of integron-harboring isolates revealed a high number of mobile genetic elements and clinically relevant antibiotic resistance genes, of which we highlight the presence of as mcr-1, qnrA1, blaGES−11, mphA, and oqxAB. The study of class 1 (n = 8), class 2 (n = 3) and class 3 (n = 1) integrons, harbored by species such as Morganella morganii, Escherichia coli, Klebsiella pneumoniae, led to the identification of different integron promoters (PcW, PcH1, PcS, and PcWTNG−10) and cassette arrays (containing drfA, aadA, cmlA, estX, sat, and blaGES). In fact, the diverse integron backbones were associated with transposable elements (e.g., Tn402, Tn7, ISCR1, Tn2*, IS26, IS1326, and IS3) that conferred greater mobility. This is also the first appearance of In1258, In1259, and In3-13, which should be monitored to prevent their establishment as successfully dispersed mobile resistance integrons. These results underscore the growing concern about the dissemination of acquired resistance genes by mobile elements in the food chain.
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Affiliation(s)
- Daniela Jones-Dias
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo JorgeLisbon, Portugal; Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto UniversityOporto, Portugal
| | - Vera Manageiro
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo JorgeLisbon, Portugal; Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto UniversityOporto, Portugal
| | - Eugénia Ferreira
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge Lisbon, Portugal
| | - Paula Barreiro
- Innovation and Technology Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge Lisbon, Portugal
| | - Luís Vieira
- Innovation and Technology Unit, Human Genetics Department, National Institute of Health Doutor Ricardo Jorge Lisbon, Portugal
| | - Inês B Moura
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo JorgeLisbon, Portugal; Centre for the Studies of Animal Science, Institute of Agrarian and Agri-Food Sciences and Technologies, Oporto UniversityOporto, Portugal
| | - Manuela Caniça
- National Reference Laboratory of Antibiotic Resistances and Healthcare Associated Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge Lisbon, Portugal
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11
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Abstract
Transposons of the Tn3 family form a widespread and remarkably homogeneous group of bacterial transposable elements in terms of transposition functions and an extremely versatile system for mediating gene reassortment and genomic plasticity owing to their modular organization. They have made major contributions to antimicrobial drug resistance dissemination or to endowing environmental bacteria with novel catabolic capacities. Here, we discuss the dynamic aspects inherent to the diversity and mosaic structure of Tn3-family transposons and their derivatives. We also provide an overview of current knowledge of the replicative transposition mechanism of the family, emphasizing most recent work aimed at understanding this mechanism at the biochemical level. Previous and recent data are put in perspective with those obtained for other transposable elements to build up a tentative model linking the activities of the Tn3-family transposase protein with the cellular process of DNA replication, suggesting new lines for further investigation. Finally, we summarize our current view of the DNA site-specific recombination mechanisms responsible for converting replicative transposition intermediates into final products, comparing paradigm systems using a serine recombinase with more recently characterized systems that use a tyrosine recombinase.
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Waldron LS, Gillings MR. Screening Foodstuffs for Class 1 Integrons and Gene Cassettes. J Vis Exp 2015:e52889. [PMID: 26132232 DOI: 10.3791/52889] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Antibiotic resistance is one of the greatest threats to health in the 21st century. Acquisition of resistance genes via lateral gene transfer is a major factor in the spread of diverse resistance mechanisms. Amongst the DNA elements facilitating lateral transfer, the class 1 integrons have largely been responsible for spreading antibiotic resistance determinants amongst Gram negative pathogens. In total, these integrons have acquired and disseminated over 130 different antibiotic resistance genes. With continued antibiotic use, class 1 integrons have become ubiquitous in commensals and pathogens of humans and their domesticated animals. As a consequence, they can now be found in all human waste streams, where they continue to acquire new genes, and have the potential to cycle back into humans via the food chain. This protocol details a streamlined approach for detecting class 1 integrons and their associated resistance gene cassettes in foodstuffs, using culturing and PCR. Using this protocol, researchers should be able to: collect and prepare samples to make enriched cultures and screen for class 1 integrons; isolate single bacterial colonies to identify integron-positive isolates; identify bacterial species that contain class 1 integrons; and characterize these integrons and their associated gene cassettes.
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13
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Abstract
Integrons are versatile gene acquisition systems commonly found in bacterial genomes. They are ancient elements that are a hot spot for genomic complexity, generating phenotypic diversity and shaping adaptive responses. In recent times, they have had a major role in the acquisition, expression, and dissemination of antibiotic resistance genes. Assessing the ongoing threats posed by integrons requires an understanding of their origins and evolutionary history. This review examines the functions and activities of integrons before the antibiotic era. It shows how antibiotic use selected particular integrons from among the environmental pool of these elements, such that integrons carrying resistance genes are now present in the majority of Gram-negative pathogens. Finally, it examines the potential consequences of widespread pollution with the novel integrons that have been assembled via the agency of human antibiotic use and speculates on the potential uses of integrons as platforms for biotechnology.
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14
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IMP-1 encoded by a novel Tn402-like class 1 integron in clinical Achromobacter xylosoxidans, China. Sci Rep 2014; 4:7212. [PMID: 25428613 PMCID: PMC4245530 DOI: 10.1038/srep07212] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 10/29/2014] [Indexed: 01/22/2023] Open
Abstract
Achromobacter xylosoxidans strain A22732 is isolated from a pneumonia patient in China and produces carbapenemases OXA-114e and IMP-1, which are encoded by chromosome and plasmid, respectively, and confer resistance to multiple ß-lactam antibiotics including carbapenems. The blaIMP-1 gene together with aacA7 and orfE is captured by a novel Tn402-like class 1 integron in a conjugative IncP-1ß plasmid. In addition to the intrinsic integron promoter PcW, there is still a blaIMP-1 gene cassette-specific promoter. This is the first report of carbapenemase-encoding IncP-1ß plasmid in clinical bacterial isolate.
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15
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Jackson RW, Vinatzer B, Arnold DL, Dorus S, Murillo J. The influence of the accessory genome on bacterial pathogen evolution. Mob Genet Elements 2014; 1:55-65. [PMID: 22016845 DOI: 10.4161/mge.1.1.16432] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 05/09/2011] [Accepted: 05/10/2011] [Indexed: 01/15/2023] Open
Abstract
Bacterial pathogens exhibit significant variation in their genomic content of virulence factors. This reflects the abundance of strategies pathogens evolved to infect host organisms by suppressing host immunity. Molecular arms-races have been a strong driving force for the evolution of pathogenicity, with pathogens often encoding overlapping or redundant functions, such as type III protein secretion effectors and hosts encoding ever more sophisticated immune systems. The pathogens' frequent exposure to other microbes, either in their host or in the environment, provides opportunities for the acquisition or interchange of mobile genetic elements. These DNA elements accessorize the core genome and can play major roles in shaping genome structure and altering the complement of virulence factors. Here, we review the different mobile genetic elements focusing on the more recent discoveries and highlighting their role in shaping bacterial pathogen evolution.
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Affiliation(s)
- Robert W Jackson
- School of Biological Sciences; University of Reading; Whiteknights; Reading, UK
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16
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Domingues S, da Silva GJ, Nielsen KM. Integrons: Vehicles and pathways for horizontal dissemination in bacteria. Mob Genet Elements 2014; 2:211-223. [PMID: 23550063 PMCID: PMC3575428 DOI: 10.4161/mge.22967] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Integrons are genetic elements first described at the end of the 1980s. Although most integrons were initially described in human clinical isolates, they have now been identified in many non-clinical environments, such as water and soil. Integrons are present in ≈10% of the sequenced bacterial genomes and are frequently linked to mobile genetic elements (MGEs); particularly the class 1 integrons. Genetic linkage to a diverse set of MGEs facilitates horizontal transfer of class 1 integrons within and between bacterial populations and species. The mechanistic aspects limiting transfer of MGEs will therefore limit the transfer of class 1 integrons. However, horizontal movement due to genes provided in trans and homologous recombination can result in class 1 integron dynamics independent of MGEs. A key determinant for continued dissemination of class 1 integrons is the probability that transferred MGEs will be vertically inherited in the recipient bacterial population. Heritability depends both on genetic stability as well as the fitness costs conferred to the host. Here we review the factors known to govern the dissemination of class 1 integrons in bacteria.
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Affiliation(s)
- Sara Domingues
- Centre of Pharmaceutical Studies; Faculty of Pharmacy; University of Coimbra; Coimbra, Portugal ; Department of Pharmacy; Faculty of Health Sciences; University of Tromsø; Tromsø, Norway
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17
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Kim M, Kwon TH, Jung SM, Cho SH, Jin SY, Park NH, Kim CG, Kim JS. Antibiotic resistance of bacteria isolated from the internal organs of edible snow crabs. PLoS One 2013; 8:e70887. [PMID: 23990916 PMCID: PMC3749200 DOI: 10.1371/journal.pone.0070887] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 06/25/2013] [Indexed: 02/01/2023] Open
Abstract
Antibiotic resistance and microbiota within edible snow crabs are important for the Chionoecetes (snow crab) fishing industry. We investigated these parameters using culture methods and antibiotic susceptibility tests with six internal organs from three species of Chionoecetes. Each sample revealed many unexpected microbial species within Chionoecetes internal organs. On the basis of 16S rRNA sequence analysis of 381 isolates, the most abundant genera identified in Chionoecetes opilio were Acinetobacter spp. (24%), Bacillus spp. (4%), Pseudomonas spp. (34%), Stenotrophomonas spp. (28%), and Agreia spp. (11%). In Chionoecetes sp. crabs, Acinetobacter spp. (23%), Bacillus spp. (12%), and Psychrobacter spp. (20%) were most prevalent, while Agreia spp. (11%), Bacillus spp. (31%), Microbacterium spp. (10%), Rhodococcus spp. (12%), and Agrococcus spp. (6%) were most abundant in C. japonicus. Our antibiotic resistance test found resistance to all nine antibiotics tested in 19, 14, and two of the isolates from C. opilio, Chionoecetes sp., and, C. japonicus respectively. Our results are the first to show that microbes with antibiotic resistance are widely distributed throughout the internal organs of natural snow crabs.
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Affiliation(s)
- Misoon Kim
- Gyeongbuk Institute for Marine Bioindustry, Jukbyeon-Meon, Uljin-Gun, Gyeongbuk, Republic of Korea
| | - Tae-Hyung Kwon
- Gyeongbuk Institute for Marine Bioindustry, Jukbyeon-Meon, Uljin-Gun, Gyeongbuk, Republic of Korea
| | - Su-Mi Jung
- Division of Enteric Bacterial Infections, Center for Infectious Diseases, Korea National Institute of Health, Cheongwon-Gun, Chungcheongbuk, Republic of Korea
| | - Seung-Hak Cho
- Division of Enteric Bacterial Infections, Center for Infectious Diseases, Korea National Institute of Health, Cheongwon-Gun, Chungcheongbuk, Republic of Korea
| | - Seon Yeong Jin
- Gyeongbuk Institute for Marine Bioindustry, Jukbyeon-Meon, Uljin-Gun, Gyeongbuk, Republic of Korea
| | - Nyun-Ho Park
- Gyeongbuk Institute for Marine Bioindustry, Jukbyeon-Meon, Uljin-Gun, Gyeongbuk, Republic of Korea
| | - Choong-Gon Kim
- Gyeongbuk Institute for Marine Bioindustry, Jukbyeon-Meon, Uljin-Gun, Gyeongbuk, Republic of Korea
| | - Jong-Shik Kim
- Gyeongbuk Institute for Marine Bioindustry, Jukbyeon-Meon, Uljin-Gun, Gyeongbuk, Republic of Korea
- * E-mail:
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18
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Amábile-Cuevas CF. Antibiotic resistance: from Darwin to Lederberg to Keynes. Microb Drug Resist 2012; 19:73-87. [PMID: 23046150 DOI: 10.1089/mdr.2012.0115] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The emergence and spread of antibiotic-resistant bacteria reflects both, a gradual, completely Darwinian evolution, which mostly yields slight decreases in antibiotic susceptibility, along with phenotypes that are not precisely characterized as "resistance"; and sudden changes, from full susceptibility to full resistance, which are driven by a vast array of horizontal gene transfer mechanisms. Antibiotics select for more than just antibiotic resistance (i.e., increased virulence and enhanced gene exchange abilities); and many non-antibiotic agents or conditions select for or maintain antibiotic resistance traits as a result of a complex network of underlying and often overlapping mechanisms. Thus, the development of new antibiotics and thoughtful, integrated anti-infective strategies is needed to address the immediate and long-term threat of antibiotic resistance. Since the biology of resistance is complex, these new drugs and strategies will not come from free-market forces, or from "incentives" for pharmaceutical companies.
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19
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El Salabi A, Walsh TR, Chouchani C. Extended spectrum β-lactamases, carbapenemases and mobile genetic elements responsible for antibiotics resistance in Gram-negative bacteria. Crit Rev Microbiol 2012; 39:113-22. [DOI: 10.3109/1040841x.2012.691870] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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20
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Genetic context and structural diversity of class 1 integrons from human commensal bacteria in a hospital intensive care unit. Antimicrob Agents Chemother 2011; 55:3939-43. [PMID: 21628540 DOI: 10.1128/aac.01831-10] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Most surveys for class 1 integrons are at least partly predicated on PCR screening that targets integron conserved regions. However, class 1 integrons are structurally diverse, so dependence on conserved regions may lead to missing clinically relevant examples of class 1 integrons. Here, we surveyed a commensal population of bacteria from patients in an intensive care unit to identify class 1 integrons irrespective of their structure or genetic context. We identified several examples of class 1 integrons linked to complete Tn402-like or Tn402 hybrid transposition modules and diverse insertion points with respect to the inverted repeat IRi boundary. The diversity and abundance of class 1 integrons identified are such that many novel elements seen here would not have been identified by commonly used methods, and they revealed an additional level of complexity.
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21
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Heuer H, Schmitt H, Smalla K. Antibiotic resistance gene spread due to manure application on agricultural fields. Curr Opin Microbiol 2011; 14:236-43. [PMID: 21546307 DOI: 10.1016/j.mib.2011.04.009] [Citation(s) in RCA: 599] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Revised: 04/06/2011] [Accepted: 04/11/2011] [Indexed: 10/18/2022]
Abstract
The usage of antibiotics in animal husbandry has promoted the development and abundance of antibiotic resistance in farm environments. Manure has become a reservoir of resistant bacteria and antibiotic compounds, and its application to agricultural soils is assumed to significantly increase antibiotic resistance genes and selection of resistant bacterial populations in soil. The genome location of resistance genes is likely to shift towards mobile genetic elements such as broad-host-range plasmids, integrons, and transposable elements. Horizontal transfer of these elements to bacteria adapted to soil or other habitats supports their environmental transmission independent of the original host. The human exposure to soil-borne resistance has yet to be determined, but is likely to be severely underestimated.
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Affiliation(s)
- Holger Heuer
- Julius Kühn-Institute-Federal Research Centre for Cultivated Plants (JKI), Department Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany.
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