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Shaw LP, Neher RA. Visualizing and quantifying structural diversity around mobile resistance genes. Microb Genom 2023; 9:001168. [PMID: 38117673 PMCID: PMC10763510 DOI: 10.1099/mgen.0.001168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 12/07/2023] [Indexed: 12/22/2023] Open
Abstract
Understanding the evolution of mobile genes is important for understanding the spread of antimicrobial resistance (AMR). Many clinically important AMR genes have been mobilized by mobile genetic elements (MGEs) on the kilobase scale, such as integrons and transposons, which can integrate into both chromosomes and plasmids and lead to rapid spread of the gene through bacterial populations. Looking at the flanking regions of these mobile genes in diverse genomes can highlight common structures and reveal patterns of MGE spread. However, historically this has been a largely descriptive process, relying on gene annotation and expert knowledge. Here we describe a general method to visualize and quantify the structural diversity around genes using pangraph to find blocks of homologous sequence. We apply this method to a set of 12 clinically important beta-lactamase genes and provide interactive visualizations of their flanking regions at https://liampshaw.github.io/flanking-regions. We show that nucleotide-level variation in the mobile gene itself generally correlates with increased structural diversity in its flanking regions, demonstrating a relationship between rates of mutational evolution and rates of structural evolution, and find a bias for greater structural diversity upstream. Our framework is a starting point to investigate general rules that apply to the horizontal spread of new genes through bacterial populations.
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Affiliation(s)
- Liam P. Shaw
- Department of Biology, University of Oxford, Oxford, UK
- Department of Biosciences, University of Durham, Durham, UK
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2
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Epidemiology of Plasmid Lineages Mediating the Spread of Extended-Spectrum Beta-Lactamases among Clinical Escherichia coli. mSystems 2022; 7:e0051922. [PMID: 35993734 PMCID: PMC9601178 DOI: 10.1128/msystems.00519-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The prevalence of extended-spectrum beta-lactamases (ESBLs) among clinical isolates of Escherichia coli has been increasing, with this spread driven by ESBL-encoding plasmids. However, the epidemiology of ESBL-disseminating plasmids remains understudied, obscuring the roles of individual plasmid lineages in ESBL spread. To address this, we performed an in-depth genomic investigation of 149 clinical ESBL-like E. coli isolates from a tertiary care hospital. We obtained high-quality assemblies for 446 plasmids, revealing an extensive map of plasmid sharing that crosses time, space, and bacterial sequence type boundaries. Through a sequence-based network, we identified specific plasmid lineages that are responsible for the dissemination of major ESBLs. Notably, we demonstrate that IncF plasmids separate into 2 distinct lineages that are enriched for different ESBLs and occupy distinct host ranges. Our work provides a detailed picture of plasmid-mediated spread of ESBLs, demonstrating the extensive sequence diversity within identified lineages, while highlighting the genetic elements that underlie the persistence of these plasmids within the clinical E. coli population. IMPORTANCE The increasing incidence of nosocomial infections with extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli represents a significant threat to public health, given the limited treatment options available for such infections. The rapid ESBL spread is suggested to be driven by localization of the resistance genes on conjugative plasmids. Here, we identify the contributions of different plasmid lineages in the nosocomial spread of ESBLs. We provide further support for plasmid-mediated spread of ESBLs but demonstrate that some ESBL genes rely on dissemination through plasmids more than the others. We identify key plasmid lineages that are enriched in major ESBL genes and highlight the encoded genetic elements that facilitate the transmission and stable maintenance of these plasmid groups within the clinical E. coli population. Overall, our work provides valuable insight into the dissemination of ESBLs through plasmids, furthering our understating of factors underlying the increased prevalence of these genes in nosocomial settings.
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3
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How Do Transposable Elements Activate Expression of Transcriptionally Silent Antibiotic Resistance Genes? Int J Mol Sci 2022; 23:ijms23158063. [PMID: 35897639 PMCID: PMC9330008 DOI: 10.3390/ijms23158063] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 07/17/2022] [Accepted: 07/20/2022] [Indexed: 02/06/2023] Open
Abstract
The rapidly emerging phenomenon of antibiotic resistance threatens to substantially reduce the efficacy of available antibacterial therapies. Dissemination of resistance, even between phylogenetically distant bacterial species, is mediated mainly by mobile genetic elements, considered to be natural vectors of horizontal gene transfer. Transposable elements (TEs) play a major role in this process—due to their highly recombinogenic nature they can mobilize adjacent genes and can introduce them into the pool of mobile DNA. Studies investigating this phenomenon usually focus on the genetic load of transposons and the molecular basis of their mobility. However, genes introduced into evolutionarily distant hosts are not necessarily expressed. As a result, bacterial genomes contain a reservoir of transcriptionally silent genetic information that can be activated by various transposon-related recombination events. The TEs themselves along with processes associated with their transposition can introduce promoters into random genomic locations. Thus, similarly to integrons, they have the potential to convert dormant genes into fully functional antibiotic resistance determinants. In this review, we describe the genetic basis of such events and by extension the mechanisms promoting the emergence of new drug-resistant bacterial strains.
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Xie M, Yang X, Xu Q, Ye L, Chen K, Zheng Z, Dong N, Sun Q, Shu L, Gu D, Chan EWC, Zhang R, Chen S. Clinical evolution of ST11 carbapenem resistant and hypervirulent Klebsiella pneumoniae. Commun Biol 2021; 4:650. [PMID: 34075192 PMCID: PMC8169677 DOI: 10.1038/s42003-021-02148-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 04/23/2021] [Indexed: 11/18/2022] Open
Abstract
Carbapenem-resistant and hypervirulent K. pneumoniae (CR-HvKP) strains that have emerged recently have caused infections of extremely high mortality in various countries. In this study, we discovered a conjugative plasmid that encodes carbapenem resistance and hypervirulence in a clinical ST86 K2 CR-HvKP, namely 17ZR-91. The conjugative plasmid (p17ZR-91-Vir-KPC) was formed by fusion of a non-conjugative pLVPK-like plasmid and a conjugative blaKPC-2-bearing plasmid and is present dynamically with two other non-fusion plasmids. Conjugation of p17ZR-91-Vir-KPC to other K. pneumoniae enabled them to rapidly express the carbapenem resistance and hypervirulence phenotypes. More importantly, genome analysis provided direct evidence that p17ZR-91-Vir-KPC could be directly transmitted from K2 CR-HvKP strain, 17ZR-91, to ST11 clinical K. pneumoniae strains to convert them into ST11 CR-HvKP strains, which explains the evolutionary mechanisms of recently emerged ST11 CR-HvKP strains. Carbapenem-resistant and hypervirulent Klebsiella pneumoniae strains are emerging. Here Xie et al. show that these phenotypes are carried on a plasmid formed from the fusion of a virulence plasmid with a conjugative plasmid.
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Affiliation(s)
- Miaomiao Xie
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Xuemei Yang
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Qi Xu
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Lianwei Ye
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Kaichao Chen
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Zhiwei Zheng
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Ning Dong
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Qiaoling Sun
- Department of Clinical Laboratory, Second Affiliated Hospital of Zhejiang University, School of Medicine, Zhejiang, Hangzhou, China
| | - Lingbin Shu
- Department of Clinical Laboratory, Second Affiliated Hospital of Zhejiang University, School of Medicine, Zhejiang, Hangzhou, China
| | - Danxia Gu
- Department of Clinical Laboratory, Zhejiang Provincial People's Hospital, Hangzhou, China
| | - Edward Wai-Chi Chan
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong.,State Key Lab of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Rong Zhang
- Department of Clinical Laboratory, Second Affiliated Hospital of Zhejiang University, School of Medicine, Zhejiang, Hangzhou, China.
| | - Sheng Chen
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong.
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Selvakumar V, Kannan K, Panneerselvam A, Suresh M, Nooruddin T, Pal K, Elkodous MA, Nada HG, El-Bastawisy HS, Tolba MM, Noureldeen A, Darwish H, Fayad E, Khairy WA, Nasser HA, El-Sayyad GS. Molecular identification of extended spectrum β-lactamases (ESBLs)-producing strains in clinical specimens from Tiruchirappalli, India. APPLIED NANOSCIENCE 2021. [DOI: 10.1007/s13204-021-01886-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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6
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Detection of a New Resistance-Mediating Plasmid Chimera in a blaOXA-48-Positive Klebsiella pneumoniae Strain at a German University Hospital. Microorganisms 2021; 9:microorganisms9040720. [PMID: 33807212 PMCID: PMC8066831 DOI: 10.3390/microorganisms9040720] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 12/22/2022] Open
Abstract
Mobile genetic elements, such as plasmids, facilitate the spread of antibiotic resistance genes in Enterobacterales. In line with this, we investigated the plasmid-resistome of seven blaOXA-48 gene-carrying Klebsiella pneumoniae isolates, which were isolated between 2013 and 2014 at the University Medical Center in Göttingen, Germany. All isolates were subjected to complete genome sequencing including the reconstruction of entire plasmid sequences. In addition, phenotypic resistance testing was conducted. The seven isolates comprised both disease-associated isolates and colonizers isolated from five patients. They fell into two clusters of three sequence type (ST)101 and two ST11 isolates, respectively; and ST15 and ST23 singletons. The seven isolates harbored various plasmids of the incompatibility (Inc) groups IncF, IncL/M, IncN, IncR, and a novel plasmid chimera. All blaOXA-48 genes were encoded on the IncL/M plasmids. Of note, distinct phenotypical resistance patterns associated with different sets of resistance genes encoded by IncL/M and IncR plasmids were observed among isolates of the ST101 cluster in spite of high phylogenetic relatedness of the bacterial chromosomes, suggesting nosocomial transmission. This highlights the importance of plasmid uptake and plasmid recombination events for the fast generation of resistance variability after clonal transmission. In conclusion, this study contributes a piece in the puzzle of molecular epidemiology of resistance gene-carrying plasmids in K. pneumoniae in Germany.
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Song HJ, Moon DC, Mechesso AF, Kang HY, Kim MH, Choi JH, Kim SJ, Yoon SS, Lim SK. Resistance Profiling and Molecular Characterization of Extended-Spectrum/Plasmid-Mediated AmpC β-Lactamase-Producing Escherichia coli Isolated from Healthy Broiler Chickens in South Korea. Microorganisms 2020; 8:E1434. [PMID: 32962074 PMCID: PMC7564670 DOI: 10.3390/microorganisms8091434] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/12/2022] Open
Abstract
We aimed to identify and characterize extended-spectrum β-lactamase (ESBL)-and/or plasmid-mediated AmpC β-lactamase (pAmpC)-producing Escherichia coli isolated from healthy broiler chickens slaughtered for human consumption in Korea. A total of 332 E. coli isolates were identified from 339 cloacal swabs in 2019. More than 90% of the isolates were resistant to multiple antimicrobials. ESBL/pAmpC-production was noted in 14% (46/332) of the isolates. Six of the CTX-M-β-lactamase-producing isolates were found to co-harbor at least one plasmid-mediated quinolone resistance gene. We observed the co-existence of blaCMY-2 and mcr-1 genes in the same isolate for the first time in Korea. Phylogenetic analysis demonstrated that the majority of blaCMY-2-carrying isolates belonged to subgroup D. Conjugation confirmed the transferability of blaCTX-M and blaCMY-2 genes, as well as non-β-lactam resistance traits from 60.9% (28/46) of the ESBL/pAmpC-producing isolates to a recipient E. coli J53. The ISECP, IS903, and orf477 elements were detected in the upstream or downstream regions. The blaCTX-M and blaCMY-2 genes mainly belonged to the IncI1, IncHI2, and/or IncFII plasmids. Additionally, the majority of ESBL/pAmpC-producing isolates exhibited heterogeneous PFGE profiles. This study showed that healthy chickens act as reservoirs of ESBL/pAmpC-producing E. coli that can potentially be transmitted to humans.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Suk-Kyung Lim
- Bacterial Disease Division, Animal and Plant Quarantine Agency, 177 Hyeksin 8-ro, Gimcheon-si, Gyeongsangbuk-do 39660, Korea; (H.-J.S.); (D.C.M.); (A.F.M.); (H.Y.K.); (M.H.K.); (J.-H.C.); (S.-J.K.); (S.-S.Y.)
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8
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Acquired Genetic Elements that Contribute to Antimicrobial Resistance in Frequent Gram-Negative Causative Agents of Healthcare-Associated Infections. Am J Med Sci 2020; 360:631-640. [PMID: 32747008 DOI: 10.1016/j.amjms.2020.06.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/26/2020] [Accepted: 06/29/2020] [Indexed: 12/12/2022]
Abstract
Antimicrobial resistance (AMR) is a worldwide public health problem that reduces therapeutic options and increases the risk of death. The causative agents of healthcare-associated infections (HAIs) are drug-resistant microorganisms of the nosocomial environment, which have developed different mechanisms of AMR. The hospital-associated microbiota has been proposed to be a reservoir of genes associated with AMR and an environment where the transfer of genetic material among organisms may occur. The ESKAPE group (Enterococcus faecalis and Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter aerogenes and Escherichia coli) is a frequent causative agents of HAIs. In this review, we address the issue of acquired genetic elements that contribute to AMR in the most frequent Gram-negative of ESKAPE, with a focus on last resort antimicrobial agents and the role of transference of genetic elements for the development of AMR.
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Genome-based insights into the resistomes and mobilomes of two Providencia rettgeri strains isolated from wound infections in Madagascar. J Glob Antimicrob Resist 2020; 20:178-182. [DOI: 10.1016/j.jgar.2019.07.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/03/2019] [Accepted: 07/05/2019] [Indexed: 11/24/2022] Open
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10
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Ramirez MS, Iriarte A, Reyes-Lamothe R, Sherratt DJ, Tolmasky ME. Small Klebsiella pneumoniae Plasmids: Neglected Contributors to Antibiotic Resistance. Front Microbiol 2019; 10:2182. [PMID: 31616398 PMCID: PMC6764390 DOI: 10.3389/fmicb.2019.02182] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 09/05/2019] [Indexed: 12/15/2022] Open
Abstract
Klebsiella pneumoniae is the causative agent of community- and, more commonly, hospital-acquired infections. Infections caused by this bacterium have recently become more dangerous due to the acquisition of multiresistance to antibiotics and the rise of hypervirulent variants. Plasmids usually carry genes coding for resistance to antibiotics or virulence factors, and the recent sequence of complete K. pneumoniae genomes showed that most strains harbor many of them. Unlike large plasmids, small, usually high copy number plasmids, did not attract much attention. However, these plasmids may include genes coding for specialized functions, such as antibiotic resistance, that can be expressed at high levels due to gene dosage effect. These genes may be part of mobile elements that not only facilitate their dissemination but also participate in plasmid evolution. Furthermore, high copy number plasmids may also play a role in evolution by allowing coexistence of mutated and non-mutated versions of a gene, which helps to circumvent the constraints imposed by trade-offs after certain genes mutate. Most K. pneumoniae plasmids 25-kb or smaller replicate by the ColE1-type mechanism and many of them are mobilizable. The transposon Tn1331 and derivatives were found in a high percentage of these plasmids. Another transposon that was found in representatives of this group is the bla KPC-containing Tn4401. Common resistance determinants found in these plasmids were aac(6')-Ib and genes coding for β-lactamases including carbapenemases.
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Affiliation(s)
- Maria S. Ramirez
- Center for Applied Biotechnology Studies, Department of Biological Sciences, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States
| | - Andrés Iriarte
- Laboratorio de Biología Computacional, Departamento de Desarrollo Biotecnológico, Facultad de Medicina, Universidad de la República de Uruguay, Montevideo, Uruguay
| | | | - David J. Sherratt
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Marcelo E. Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Sciences, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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Rozwandowicz M, Brouwer MSM, Fischer J, Wagenaar JA, Gonzalez-Zorn B, Guerra B, Mevius DJ, Hordijk J. Plasmids carrying antimicrobial resistance genes in Enterobacteriaceae. J Antimicrob Chemother 2019; 73:1121-1137. [PMID: 29370371 DOI: 10.1093/jac/dkx488] [Citation(s) in RCA: 501] [Impact Index Per Article: 100.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bacterial antimicrobial resistance (AMR) is constantly evolving and horizontal gene transfer through plasmids plays a major role. The identification of plasmid characteristics and their association with different bacterial hosts provides crucial knowledge that is essential to understand the contribution of plasmids to the transmission of AMR determinants. Molecular identification of plasmid and strain genotypes elicits a distinction between spread of AMR genes by plasmids and dissemination of these genes by spread of bacterial clones. For this reason several methods are used to type the plasmids, e.g. PCR-based replicon typing (PBRT) or relaxase typing. Currently, there are 28 known plasmid types in Enterobacteriaceae distinguished by PBRT. Frequently reported plasmids [IncF, IncI, IncA/C, IncL (previously designated IncL/M), IncN and IncH] are the ones that bear the greatest variety of resistance genes. The purpose of this review is to provide an overview of all known AMR-related plasmid families in Enterobacteriaceae, the resistance genes they carry and their geographical distribution.
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Affiliation(s)
- M Rozwandowicz
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - M S M Brouwer
- Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - J Fischer
- Department of Biological Safety, Federal Institute for Risk Assessment, BfR, Berlin, Germany
| | - J A Wagenaar
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - B Gonzalez-Zorn
- Department of Animal Health and VISAVET, Complutense University of Madrid, Madrid, Spain
| | - B Guerra
- Department of Biological Safety, Federal Institute for Risk Assessment, BfR, Berlin, Germany
| | - D J Mevius
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - J Hordijk
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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12
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Fang LX, Li XP, Li L, Chen MY, Wu CY, Li LL, Liao XP, Liu YH, Sun J. IS Ecp1-mediated transposition of chromosome-borne blaCMY-2 into an endogenous ColE1-like plasmid in Escherichia coli. Infect Drug Resist 2018; 11:995-1005. [PMID: 30087569 PMCID: PMC6061673 DOI: 10.2147/idr.s159345] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Background CMY-2 is the most prevalent pAmpC β-lactamase, but the chromosomal blaCMY-2 gene transfer via horizontal transmission has been seldom reported. This study aimed to describe an ISEcp1-mediated transposition of a chromosomal blaCMY-2 gene from Escherichia coli into a small endogenous ColE1-like plasmid, resulting in elevated resistance to extended-spectrum cephalosporins. Methods Three ESCs-resistant ST641 E. coli strains EC6413, EC4103 and EC5106 harbored the blaCMY-2 gene. S1-PFGE, I-ceu I-PFGE, Southern blotting and electroporation experiments were performed to investigate the location and transferability of blaCMY-2. The genetic context and gene expression of blaCMY-2 in the original isolates and the corresponding electroporants were explored by PCR mapping, primer walking strategy and RT-qPCR. Results The blaCMY-2-containing region (ISEcp1-blaCMY-2-∆blc-∆yggR-∆tnp1-orf7-orf8-orf9-∆tnp2-∆hsdR) was transposed into endogenous ColE1-like plasmid pSC137 in the process of electroporation at very low frequencies (10-8-10-9). The transpositions resulted in novel larger blaCMY-2-harboring ColE1-like plasmids with size of 14,845 bp, enabling increase in MICs of 2 to 8-fold for cefotaxime, ceftiofur, and ceftazidime in recipient strains over their respective original counterparts. Transcriptional level analysis revealed that the increased blaCMY-2 expression was correlated with elevated MIC values of cephalosporins. The blaCMY-2 transposition unit was identical to that in a clinical isolate E. coli TN44889 from France isolated in 2004. Conclusions Our results firstly demonstrated that ISEcp1 mediated a transposition of chromosome-borne blaCMY-2 into an endogenous ColE1-like plasmid by electroporation. Amplification of the blaCMY-2 gene facilitates the strain adaptation to a changed environment with an elevated antibiotic pressure.
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Affiliation(s)
- Liang-Xing Fang
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
| | - Xing-Ping Li
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
| | - Liang Li
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
| | - Mu-Ya Chen
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
| | - Cai-Yan Wu
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Guangzhou, People's Republic of China
| | - Lu-Lu Li
- Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, People's Republic of China
| | - Xiao-Ping Liao
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
| | - Ya-Hong Liu
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
| | - Jian Sun
- National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, South China Agricultural University, Guangzhou, People's Republic of China, .,Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, South China Agricultural University, Guangzhou, People's Republic of China,
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13
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Borowiak M, Fischer J, Hammerl JA, Hendriksen RS, Szabo I, Malorny B. Identification of a novel transposon-associated phosphoethanolamine transferase gene, mcr-5, conferring colistin resistance in d-tartrate fermenting Salmonella enterica subsp. enterica serovar Paratyphi B. J Antimicrob Chemother 2018; 72:3317-3324. [PMID: 28962028 DOI: 10.1093/jac/dkx327] [Citation(s) in RCA: 357] [Impact Index Per Article: 59.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 08/04/2017] [Indexed: 01/17/2023] Open
Abstract
Objectives Plasmid-mediated mobilized colistin resistance is currently known to be caused by phosphoethanolamine transferases termed MCR-1, MCR-2, MCR-3 and MCR-4. However, this study focuses on the dissection of a novel resistance mechanism in mcr-1-, mcr-2- and mcr-3-negative d-tartrate fermenting Salmonella enterica subsp. enterica serovar Paratyphi B (Salmonella Paratyphi B dTa+) isolates with colistin MIC values >2 mg/L. Methods A selected isolate from the strain collection of the German National Reference Laboratory for Salmonella was investigated by WGS and bioinformatical analysis to identify novel phosphoethanolamine transferase genes involved in colistin resistance. Subsequently PCR screening, S1-PFGE and DNA-DNA hybridization were performed to analyse the prevalence and location of the identified mcr-5 gene. Cloning and transformation experiments in Escherichia coli DH5α and Salmonella Paratyphi B dTa+ control strains were carried out and the activity of MCR-5 was determined in vitro by MIC testing. Results In this study, we identified a novel phosphoethanolamine transferase in 14 mcr-1-, mcr-2- and mcr-3-negative Salmonella Paratyphi B dTa+ isolates with colistin MIC values >2 mg/L that were received during 2011-13. The respective gene, further termed as mcr-5 (1644 bp), is part of a 7337 bp transposon of the Tn3 family and usually located on related multi-copy ColE-type plasmids. Interestingly, in one isolate an additional subclone with a chromosomal location of the mcr-5 transposon was observed. Conclusions Our findings suggest that the transfer of colistin-resistance-mediating phosphoethanolamine transferase genes from bacterial chromosomes to mobile genetic elements has occurred in multiple independent events raising concern regarding their variety, prevalence and impact on public health.
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Affiliation(s)
- Maria Borowiak
- German Federal Institute for Risk Assessment, BfR, Department for Biological Safety, Berlin, Germany
| | - Jennie Fischer
- German Federal Institute for Risk Assessment, BfR, Department for Biological Safety, Berlin, Germany
| | - Jens A Hammerl
- German Federal Institute for Risk Assessment, BfR, Department for Biological Safety, Berlin, Germany
| | - Rene S Hendriksen
- National Food Institute, Technical University of Denmark, WHO Collaborating Center for Antimicrobial Resistance in Foodborne Pathogens and European Union Reference Laboratory for Antimicrobial Resistance, Kgs Lyngby, Denmark
| | - Istvan Szabo
- German Federal Institute for Risk Assessment, BfR, Department for Biological Safety, Berlin, Germany
| | - Burkhard Malorny
- German Federal Institute for Risk Assessment, BfR, Department for Biological Safety, Berlin, Germany
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Vandecraen J, Chandler M, Aertsen A, Van Houdt R. The impact of insertion sequences on bacterial genome plasticity and adaptability. Crit Rev Microbiol 2017; 43:709-730. [PMID: 28407717 DOI: 10.1080/1040841x.2017.1303661] [Citation(s) in RCA: 230] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Transposable elements (TE), small mobile genetic elements unable to exist independently of the host genome, were initially believed to be exclusively deleterious genomic parasites. However, it is now clear that they play an important role as bacterial mutagenic agents, enabling the host to adapt to new environmental challenges and to colonize new niches. This review focuses on the impact of insertion sequences (IS), arguably the smallest TE, on bacterial genome plasticity and concomitant adaptability of phenotypic traits, including resistance to antibacterial agents, virulence, pathogenicity and catabolism. The direct consequence of IS transposition is the insertion of one DNA sequence into another. This event can result in gene inactivation as well as in modulation of neighbouring gene expression. The latter is usually mediated by de-repression or by the introduction of a complete or partial promoter located within the element. Furthermore, transcription and transposition of IS are affected by host factors and in some cases by environmental signals offering the host an adaptive strategy and promoting genetic variability to withstand the environmental challenges.
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Affiliation(s)
- Joachim Vandecraen
- a Microbiology Unit, Interdisciplinary Biosciences , Belgian Nuclear Research Centre (SCK•CEN) , Mol , Belgium.,b Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre , Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering , KU Leuven , Leuven , Belgium
| | - Michael Chandler
- c Laboratoire de Microbiologie et Génétique Moléculaires, Centre national de la recherche scientifique , Toulouse , France
| | - Abram Aertsen
- b Laboratory of Food Microbiology and Leuven Food Science and Nutrition Research Centre , Department of Microbial and Molecular Systems, Faculty of Bioscience Engineering , KU Leuven , Leuven , Belgium
| | - Rob Van Houdt
- a Microbiology Unit, Interdisciplinary Biosciences , Belgian Nuclear Research Centre (SCK•CEN) , Mol , Belgium
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15
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Le V, Nhu NTK, Cerdeno-Tarraga A, Campbell JI, Tuyen HT, Nhu TDH, Tam PTT, Schultsz C, Thwaites G, Thomson NR, Baker S. Genetic characterization of three qnrS1-harbouring multidrug-resistance plasmids and qnrS1-containing transposons circulating in Ho Chi Minh City, Vietnam. J Med Microbiol 2015; 64:869-878. [PMID: 26272054 PMCID: PMC4635468 DOI: 10.1099/jmm.0.000100] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Plasmid-mediated quinolone resistance (PMQR) refers to a family of closely related genes that confer decreased susceptibility to fluoroquinolones. PMQR genes are generally associated with integrons and/or plasmids that carry additional antimicrobial resistance genes active against a range of antimicrobials. In Ho Chi Minh City (HCMC), Vietnam, we have previously shown a high frequency of PMQR genes within commensal Enterobacteriaceae. However, there are limited available sequence data detailing the genetic context in which the PMQR genes reside, and a lack of understanding of how these genes spread across the Enterobacteriaceae. Here, we aimed to determine the genetic background facilitating the spread and maintenance of qnrS1, the dominant PMQR gene circulating in HCMC. We sequenced three qnrS1-carrying plasmids in their entirety to understand the genetic context of these qnrS1-embedded plasmids and also the association of qnrS1-mediated quinolone resistance with other antimicrobial resistance phenotypes. Annotation of the three qnrS1-containing plasmids revealed a qnrS1-containing transposon with a closely related structure. We screened 112 qnrS1-positive commensal Enterobacteriaceae isolated in the community and in a hospital in HCMC to detect the common transposon structure. We found the same transposon structure to be present in 71.4 % (45/63) of qnrS1-positive hospital isolates and in 36.7 % (18/49) of qnrS1-positive isolates from the community. The resulting sequence analysis of the qnrS1 environment suggested that qnrS1 genes are widely distributed and are mobilized on elements with a common genetic background. Our data add additional insight into mechanisms that facilitate resistance to multiple antimicrobials in Gram-negative bacteria in Vietnam.
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Affiliation(s)
- Vien Le
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.,Division of Infectious Diseases, Department of Medicine, University of California, San Francisco, CA, USA
| | - Nguyen Thi Khanh Nhu
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.,School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Australia
| | | | - James I Campbell
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, UK
| | - Ha Thanh Tuyen
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Tran Do Hoang Nhu
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Pham Thi Thanh Tam
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Constance Schultsz
- Department of Medical Microbiology, Academic Medical Centre, University of Amsterdam, The Netherlands
| | - Guy Thwaites
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.,Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, UK
| | - Nicholas R Thomson
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, UK.,London School of Hygiene and Tropical Medicine, London, UK
| | - Stephen Baker
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, UK.,Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.,London School of Hygiene and Tropical Medicine, London, UK
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16
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Papagiannitsis CC, Dolejska M, Izdebski R, Dobiasova H, Studentova V, Esteves FJ, Derde LPG, Bonten MJM, Hrabák J, Gniadkowski M. Characterization of pKP-M1144, a Novel ColE1-Like Plasmid Encoding IMP-8, GES-5, and BEL-1 β-Lactamases, from a Klebsiella pneumoniae Sequence Type 252 Isolate. Antimicrob Agents Chemother 2015; 59:5065-8. [PMID: 26033721 PMCID: PMC4505226 DOI: 10.1128/aac.00937-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 05/29/2015] [Indexed: 11/20/2022] Open
Abstract
IMP-8 metallo-β-lactamase was identified in Klebsiella pneumoniae sequence type 252 (ST252), isolated in a Portuguese hospital in 2009. blaIMP-8 was the first gene cassette of a novel class 3 integron, In1144, also carrying the blaGES-5, blaBEL-1, and aacA4 cassettes. In1144 was located on a ColE1-like plasmid, pKP-M1144 (12,029 bp), with a replication region of limited nucleotide similarity to those of other RNA-priming plasmids, such as pJHCMW1. In1144 and pKP-M1144 represent an interesting case of evolution of resistance determinants in Gram-negative bacteria.
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Affiliation(s)
- Costas C Papagiannitsis
- Faculty of Medicine and University Hospital in Plzen, Charles University in Prague, Plzen, Czech Republic National Medicines Institute, Warsaw, Poland
| | - Monika Dolejska
- Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic CEITEC VFU, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic
| | | | - Hana Dobiasova
- Department of Biology and Wildlife Diseases, Faculty of Veterinary Hygiene and Ecology, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic CEITEC VFU, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic
| | - Vendula Studentova
- Faculty of Medicine and University Hospital in Plzen, Charles University in Prague, Plzen, Czech Republic
| | | | | | | | - Jaroslav Hrabák
- Faculty of Medicine and University Hospital in Plzen, Charles University in Prague, Plzen, Czech Republic Biomedical Center, Faculty of Medicine in Plzen, Charles University in Prague, Plzen, Czech Republic
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Raji MA, Jamal W, Ojemeh O, Rotimi VO. Sequence analysis of genes mediating extended-spectrum beta-lactamase (ESBL) production in isolates of Enterobacteriaceae in a Lagos Teaching Hospital, Nigeria. BMC Infect Dis 2015; 15:259. [PMID: 26149073 PMCID: PMC4493960 DOI: 10.1186/s12879-015-1005-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 06/30/2015] [Indexed: 02/07/2023] Open
Abstract
Background Extended-spectrum β-lactamases (ESBLs) in Gram-negative organisms is now a major concern in Enterobacteriaceae worldwide. This study determined a point-prevalence and genetic profiles of ESBL-producing isolates among members of the family Enterobacteriaceae in Lagos State University Teaching Hospital Ikeja, Nigeria. Methods Consecutive non-repetitive invasive multidrug-resistant isolates of the family Enterobacteriaceae obtained over a period of 1 month (October 2011) were studied. The isolates were identified using VITEK-2/VITEK MS Systems. Susceptibility testing was performed using E test technique; results were interpreted according to the criteria recommended by the Clinical and Laboratory Standards Institute (CLSI, 2012). ESBL production was detected by E test ESBL method and confirmed by polymerase chain reaction (PCR). Results During the one-month study period, 38 isolates with ESBL phenotypic characteristics were identified and confirmed by PCR. Of these, 21 (55.3 %) were E. coli, 12 (31.6 %) K. pneumoniae, 3 (7.9 %) Proteus spp., 1 (2.6 %) each M. morganii and C. freundii. Thirty (79 %) harbored blaCTX-M genes. Sequence analysis revealed that they were all blaCTX-M-15 genes. Twenty-nine (96.7 %) of these, also harbored blaTEM genes simultaneously. All the CTX-M-15-producing isolates carried insertion sequence blaISEcP1 upstream of blaCTX-M-15 genes. The E. coli isolates were genetically heterogeneous, while the K. pneumoniae had 98 % homology. Conclusions Our point-prevalence surveillance study revealed a high prevalence of Enterobacteriaceae isolates harboring blaCTX-M-15 in the Hospital. Urgent implementation of antibiotic stewardship and other preventive strategies are necessary at this time in our hospital.
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Affiliation(s)
- Muhabat Adeola Raji
- Department of Medical Microbiology and Parasitology, Lagos State University College of Medicine/Lagos State University Teaching Hospital, Ikeja, Nigeria. .,Microbiology Laboratory, BT Health and Diagnostic Centre, Lagos State University Teaching Hospital, Ikeja, Nigeria.
| | - Wafaa Jamal
- Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait City, Kuwait.
| | - Omoh Ojemeh
- Microbiology Laboratory, BT Health and Diagnostic Centre, Lagos State University Teaching Hospital, Ikeja, Nigeria.
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San Millan A, Santos-Lopez A, Ortega-Huedo R, Bernabe-Balas C, Kennedy SP, Gonzalez-Zorn B. Small-plasmid-mediated antibiotic resistance is enhanced by increases in plasmid copy number and bacterial fitness. Antimicrob Agents Chemother 2015; 59:3335-41. [PMID: 25824216 PMCID: PMC4432117 DOI: 10.1128/aac.00235-15] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/16/2015] [Indexed: 11/20/2022] Open
Abstract
Plasmids play a key role in the horizontal spread of antibiotic resistance determinants among bacterial pathogens. When an antibiotic resistance plasmid arrives in a new bacterial host, it produces a fitness cost, causing a competitive disadvantage for the plasmid-bearing bacterium in the absence of antibiotics. On the other hand, in the presence of antibiotics, the plasmid promotes the survival of the clone. The adaptations experienced by plasmid and bacterium in the presence of antibiotics during the first generations of coexistence will be crucial for the progress of the infection and the maintenance of plasmid-mediated resistance once the treatment is over. Here we developed a model system using the human pathogen Haemophilus influenzae carrying the small plasmid pB1000 conferring resistance to β-lactam antibiotics to investigate host and plasmid adaptations in the course of a simulated ampicillin therapy. Our results proved that plasmid-bearing clones compensated for the fitness disadvantage during the first 100 generations of plasmid-host adaptation. In addition, ampicillin treatment was associated with an increase in pB1000 copy number. The augmentation in both bacterial fitness and plasmid copy number gave rise to H. influenzae populations with higher ampicillin resistance levels. In conclusion, we show here that the modulations in bacterial fitness and plasmid copy number help a plasmid-bearing bacterium to adapt during antibiotic therapy, promoting both the survival of the host and the spread of the plasmid.
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Affiliation(s)
- Alvaro San Millan
- Departamento de Sanidad Animal and Centro de Vigilancia Sanitaria Veterinaria, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | - Alfonso Santos-Lopez
- Departamento de Sanidad Animal and Centro de Vigilancia Sanitaria Veterinaria, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | - Rafael Ortega-Huedo
- Departamento de Sanidad Animal and Centro de Vigilancia Sanitaria Veterinaria, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | - Cristina Bernabe-Balas
- Departamento de Sanidad Animal and Centro de Vigilancia Sanitaria Veterinaria, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
| | | | - Bruno Gonzalez-Zorn
- Departamento de Sanidad Animal and Centro de Vigilancia Sanitaria Veterinaria, Facultad de Veterinaria, Universidad Complutense de Madrid, Madrid, Spain
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Complete nucleotide sequences of bla(CTX-M)-harboring IncF plasmids from community-associated Escherichia coli strains in the United States. Antimicrob Agents Chemother 2015; 59:3002-7. [PMID: 25753630 DOI: 10.1128/aac.04772-14] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 03/01/2015] [Indexed: 01/20/2023] Open
Abstract
Community-associated infections due to Escherichia coli producing CTX-M-type extended-spectrum β-lactamases are increasingly recognized in the United States. The bla(CTX-M) genes are frequently carried on IncF group plasmids. In this study, bla(CTX-M-15)-harboring plasmids pCA14 (sequence type 131 [ST131]) and pCA28 (ST44) and bla(CTX-M-14)-harboring plasmid pCA08 (ST131) were sequenced and characterized. The three plasmids were closely related to other IncFII plasmids from continents outside the United States in the conserved backbone region and multiresistance regions (MRRs). Each of the bla(CTX-M-15)-carrying plasmids pCA14 and pCA28 belonged to F31:A4:B1 (FAB [FII, FIA, FIB] formula) and showed a high level of similarity (92% coverage of pCA14 and 99% to 100% nucleotide identity), suggesting a possible common origin. The blaC(TX-M-14)-carrying plasmid pCA08 belonged to F2:A2:B20 and was highly similar to pKF3-140 from China (88% coverage of pCA08 and 99% to 100% nucleotide identity). All three plasmids carried multiple antimicrobial resistance genes and modules associated with virulence and biochemical pathways, which likely confer selective advantages for their host strains. The bla(CTX-M)-carrying IncFII-IA-IB plasmids implicated in community-associated infections in the United States shared key structural features with those identified from other continents, underscoring the global nature of this plasmid epidemic.
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Plasmid-Mediated Antibiotic Resistance and Virulence in Gram-negatives: the Klebsiella pneumoniae Paradigm. Microbiol Spectr 2014; 2:1-15. [PMID: 25705573 DOI: 10.1128/microbiolspec.plas-0016-2013] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Plasmids harbor genes coding for specific functions including virulence factors and antibiotic resistance that permit bacteria to survive the hostile environment found in the host and resist treatment. Together with other genetic elements such as integrons and transposons, and using a variety of mechanisms, plasmids participate in the dissemination of these traits resulting in the virtual elimination of barriers among different kinds of bacteria. In this article we review the current information about physiology and role in virulence and antibiotic resistance of plasmids from the gram-negative opportunistic pathogen Klebsiella pneumoniae. This bacterium has acquired multidrug resistance and is the causative agent of serious communityand hospital-acquired infections. It is also included in the recently defined ESKAPE group of bacteria that cause most of US hospital infections.
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Positive epistasis between co-infecting plasmids promotes plasmid survival in bacterial populations. ISME JOURNAL 2013; 8:601-612. [PMID: 24152711 PMCID: PMC3930321 DOI: 10.1038/ismej.2013.182] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 09/16/2013] [Accepted: 09/17/2013] [Indexed: 11/09/2022]
Abstract
Plasmids have a key role in the horizontal transfer of genes among bacteria. Although plasmids are catalysts for bacterial evolution, it is challenging to understand how they can persist in bacterial populations over the long term because of the burden they impose on their hosts (the ‘plasmid paradox'). This paradox is especially perplexing in the case of ‘small' plasmids, which are unable to self-transfer by conjugation. Here, for the first time, we investigate how interactions between co-infecting plasmids influence plasmid persistence. Using an experimental model system based on interactions between a diverse assemblage of ‘large' plasmids and a single small plasmid, pNI105, in the pathogenic bacterium Pseudomonas aeruginosa, we demonstrate that positive epistasis minimizes the cost associated with carrying multiple plasmids over the short term and increases the stability of the small plasmid over a longer time scale. In support of these experimental data, bioinformatic analysis showed that associations between small and large plasmids are more common than would be expected owing to chance alone across a range of families of bacteria; more generally, we find that co-infection with multiple plasmids is more common than would be expected owing to chance across a wide range of bacterial phyla. Collectively, these results suggest that positive epistasis promotes plasmid stability in bacterial populations. These findings pave the way for future mechanistic studies aimed at elucidating the molecular mechanisms of plasmid–plasmid interaction, and evolutionary studies aimed at understanding how the coevolution of plasmids drives the spread of plasmid-encoded traits.
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22
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Reyes-Lamothe R, Tran T, Meas D, Lee L, Li AM, Sherratt DJ, Tolmasky ME. High-copy bacterial plasmids diffuse in the nucleoid-free space, replicate stochastically and are randomly partitioned at cell division. Nucleic Acids Res 2013; 42:1042-51. [PMID: 24137005 PMCID: PMC3902917 DOI: 10.1093/nar/gkt918] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Bacterial plasmids play important roles in the metabolism, pathogenesis and bacterial evolution and are highly versatile biotechnological tools. Stable inheritance of plasmids depends on their autonomous replication and efficient partition to daughter cells at cell division. Active partition systems have not been identified for high-copy number plasmids, and it has been generally believed that they are partitioned randomly at cell division. Nevertheless, direct evidence for the cellular location of replicating and nonreplicating plasmids, and the partition mechanism has been lacking. We used as model pJHCMW1, a plasmid isolated from Klebsiella pneumoniae that includes two β-lactamase and two aminoglycoside resistance genes. Here we report that individual ColE1-type plasmid molecules are mobile and tend to be excluded from the nucleoid, mainly localizing at the cell poles but occasionally moving between poles along the long axis of the cell. As a consequence, at the moment of cell division, most plasmid molecules are located at the poles, resulting in efficient random partition to the daughter cells. Complete replication of individual molecules occurred stochastically and independently in the nucleoid-free space throughout the cell cycle, with a constant probability of initiation per plasmid.
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Affiliation(s)
- Rodrigo Reyes-Lamothe
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK, Department of Biology, McGill University, Montreal, Quebec H3G 0B1, Canada and Department of Biological Science, Center for Applied Biotechnology Studies, College of Natural Science and Mathematics, California State University Fullerton, Fullerton, CA 92834-6850, USA
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Wang Y, Song C, Duan G, Zhu J, Yang H, Xi Y, Fan Q. Transposition of ISEcp1 modulates blaCTX-M-55-mediated Shigella flexneri resistance to cefalothin. Int J Antimicrob Agents 2013; 42:507-12. [PMID: 24207017 DOI: 10.1016/j.ijantimicag.2013.08.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 08/09/2013] [Accepted: 08/12/2013] [Indexed: 11/19/2022]
Abstract
The aim of this study was to uncover the mechanisms underlying Shigella flexneri resistance to cefalothin. In this study, a resistance-related S. flexneri isolate, S. flexneri YDC, was obtained from S. flexneri mel-1998023/zz pre-incubated with cefalothin at a dose of 0.5 × the minimum inhibitory concentration. The ISEcp1 coding element was identified upstream of bla(CTX-M-55) in S. flexneri YDC. To further determine the role of ISEcp1 in S. flexneri resistance, plasmids containing bla(CTX-M-55) recombinant with or without the ISEcp1 sequence were constructed and named as pCTX and pISECTX, respectively. It was shown that Escherichia coli DH5α(pISECTX) was resistant to all β-lactams tested. In contrast, E. coli DH5α(pCTX) was sensitive to all except β-lactams cefazolin and cefalothin. In addition, reverse transcription PCR showed that expression levels of bla(CTX-M-55) were higher in E. coli DH5α(pISECTX). The Clinical and Laboratory Standards Institute (CLSI) assay demonstrated that extended-spectrum β-lactamase was only positively detected in E. coli DH5α(pISECTX) but not in E. coli DH5α(pCTX). Taken together, these results suggest that the translocated ISEcp1 element upstream of bla(CTX-M-55) is required for overexpression of bla(CTX-M-55), leading to cephalosporin resistance.
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Affiliation(s)
- Yingfang Wang
- Department of Epidemiology, College of Public Health, Zhengzhou University, Zhengzhou, Henan, PR China; Henan University of Science and Technology, Luoyang, Henan, PR China
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A cointegrate-like plasmid that facilitates dissemination by conjugation of the extended-spectrum β-lactamase CTX-M-17. Antimicrob Agents Chemother 2013; 57:5191-2. [PMID: 23877684 DOI: 10.1128/aac.01365-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Xu T, Ying J, Yao X, Song Y, Ma P, Bao B, Jiang W, Wu X, Tou H, Li P, Ren P, Fei J, Yang L, Liu Q, Xu Z, Zhou T, Ni L, Bao Q. Identification and characterization of two novel bla(KLUC) resistance genes through large-scale resistance plasmids sequencing. PLoS One 2012; 7:e47197. [PMID: 23056610 PMCID: PMC3467222 DOI: 10.1371/journal.pone.0047197] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Accepted: 09/10/2012] [Indexed: 11/18/2022] Open
Abstract
Plasmids are important antibiotic resistance determinant carriers that can disseminate various drug resistance genes among species or genera. By using a high throughput sequencing approach, two groups of plasmids of Escherichia coli (named E1 and E2, each consisting of 160 clinical E. coli strains isolated from different periods of time) were sequenced and analyzed. A total of 20 million reads were obtained and mapped onto the known resistance gene sequences. As a result, a total of 9 classes, including 36 types of antibiotic resistant genes, were identified. Among these genes, 25 and 27 single nucleotide polymorphisms (SNPs) appeared, of which 9 and 12 SNPs are nonsynonymous substitutions in the E1 and E2 samples. It is interesting to find that a novel genotype of blaKLUC, whose close relatives, blaKLUC-1 and blaKLUC-2, have been previously reported as carried on the Kluyvera cryocrescens chromosome and Enterobacter cloacae plasmid, was identified. It shares 99% and 98% amino acid identities with Kluc-1 and Kluc-2, respectively. Further PCR screening of 608 Enterobacteriaceae family isolates yielded a second variant (named blaKLUC-4). It was interesting to find that Kluc-3 showed resistance to several cephalosporins including cefotaxime, whereas blaKLUC-4 did not show any resistance to the antibiotics tested. This may be due to a positively charged residue, Arg, replaced by a neutral residue, Leu, at position 167, which is located within an omega-loop. This work represents large-scale studies on resistance gene distribution, diversification and genetic variation in pooled multi-drug resistance plasmids, and provides insight into the use of high throughput sequencing technology for microbial resistance gene detection.
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Affiliation(s)
- Teng Xu
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
- The Key Laboratory of Mammalian Reproductive Biology and Biotechnology of the Ministry of Education, Inner Mongolia University, Hohhot, Inner Mongolia Autonomous Region, People’s Republic of China
| | - Jun Ying
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Xiaoding Yao
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Yulong Song
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Ping Ma
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Bokan Bao
- College of Biological Science, Agricultural University of China, Beijing, People’s Republic of China
| | - Weiyan Jiang
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Xinmei Wu
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Huifen Tou
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Peizhen Li
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Ping Ren
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Jingxian Fei
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Lei Yang
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Qi Liu
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Zuyuan Xu
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Tieli Zhou
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
| | - Liyan Ni
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
- * E-mail: (LN); (QB)
| | - Qiyu Bao
- Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, Zhejiang, People’s Republic of China
- * E-mail: (LN); (QB)
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Kim D, Hong JSJ, Qiu Y, Nagarajan H, Seo JH, Cho BK, Tsai SF, Palsson BØ. Comparative analysis of regulatory elements between Escherichia coli and Klebsiella pneumoniae by genome-wide transcription start site profiling. PLoS Genet 2012; 8:e1002867. [PMID: 22912590 PMCID: PMC3415461 DOI: 10.1371/journal.pgen.1002867] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Accepted: 06/14/2012] [Indexed: 01/08/2023] Open
Abstract
Genome-wide transcription start site (TSS) profiles of the enterobacteria Escherichia coli and Klebsiella pneumoniae were experimentally determined through modified 5′ RACE followed by deep sequencing of intact primary mRNA. This identified 3,746 and 3,143 TSSs for E. coli and K. pneumoniae, respectively. Experimentally determined TSSs were then used to define promoter regions and 5′ UTRs upstream of coding genes. Comparative analysis of these regulatory elements revealed the use of multiple TSSs, identical sequence motifs of promoter and Shine-Dalgarno sequence, reflecting conserved gene expression apparatuses between the two species. In both species, over 70% of primary transcripts were expressed from operons having orthologous genes during exponential growth. However, expressed orthologous genes in E. coli and K. pneumoniae showed a strikingly different organization of upstream regulatory regions with only 20% identical promoters with TSSs in both species. Over 40% of promoters had TSSs identified in only one species, despite conserved promoter sequences existing in the other species. 662 conserved promoters having TSSs in both species resulted in the same number of comparable 5′ UTR pairs, and that regulatory element was found to be the most variant region in sequence among promoter, 5′ UTR, and ORF. In K. pneumoniae, 48 sRNAs were predicted and 36 of them were expressed during exponential growth. Among them, 34 orthologous sRNAs between two species were analyzed in depth, and the analysis showed that many sRNAs of K. pneumoniae, including pleiotropic sRNAs such as rprA, arcZ, and sgrS, may work in the same way as in E. coli. These results reveal a new dimension of comparative genomics such that a comparison of two genomes needs to be comprehensive over all levels of genome organization. In order to investigate similarities and differences of closely related species, most of the comparative genomics studies focus on comparing the gene contents either shared or specific for each genome. However, it is also important to investigate the differences in non-coding regulatory elements because they influence the transcriptional and post-transcriptional processes. Thus, we performed a genome-wide profiling of transcription start sites (TSSs) in two species, E. coli K-12 MG1655 and K. pneumoniae MGH78578. Experimental identification of TSSs is important for precise definition of promoter regions and 5′ untranslated regions upstream of coding genes. Comparative analysis of these regulatory elements revealed the use of multiple TSSs, identical sequence motifs of promoter and Shine-Dalgarno sequence. However, we observed that the upstream regulatory regions of the majority of operons having orthologous genes were organized with different usage of promoters and TSSs, resulting in diverse and complex gene regulation. We also found that the 5′ UTR is the least conserved regulatory element in sequence between the two species. Moreover, 34 orthologous sRNAs between E. coli and K. pneumoniae were analyzed in depth. The analysis suggested many of K. pneumoniae sRNAs might regulate the target genes as in E. coli.
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Affiliation(s)
- Donghyuk Kim
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Jay Sung-Joong Hong
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Yu Qiu
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Harish Nagarajan
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Joo-Hyun Seo
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Byung-Kwan Cho
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
| | - Shih-Feng Tsai
- Division of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli, Taiwan
| | - Bernhard Ø. Palsson
- Department of Bioengineering, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
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Zhao WH, Hu ZQ. Epidemiology and genetics of CTX-M extended-spectrum β-lactamases in Gram-negative bacteria. Crit Rev Microbiol 2012; 39:79-101. [PMID: 22697133 PMCID: PMC4086240 DOI: 10.3109/1040841x.2012.691460] [Citation(s) in RCA: 203] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CTX-M enzymes, the plasmid-mediated cefotaximases, constitute a rapidly growing family of extended-spectrum β-lactamases (ESBLs) with significant clinical impact. CTX-Ms are found in at least 26 bacterial species, particularly in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis. At least 109 members in CTX-M family are identified and can be divided into seven clusters based on their phylogeny. CTX-M-15 and CTX-M-14 are the most dominant variants. Chromosome-encoded intrinsic cefotaximases in Kluyvera spp. are proposed to be the progenitors of CTX-Ms, while ISEcp1, ISCR1 and plasmid are closely associated with their mobilization and dissemination.
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Affiliation(s)
- Wei-Hua Zhao
- Department of Microbiology and Immunology, Showa University School of Medicine, Tokyo, Japan.
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28
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Toleman MA, Walsh TR. Combinatorial events of insertion sequences and ICE in Gram-negative bacteria. FEMS Microbiol Rev 2011; 35:912-35. [DOI: 10.1111/j.1574-6976.2011.00294.x] [Citation(s) in RCA: 133] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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29
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Ma L, Siu LK, Lu PL. Effect of spacer sequences between bla(CTX-M) and ISEcp1 on bla(CTX-M) expression. J Med Microbiol 2011; 60:1787-1792. [PMID: 21799195 DOI: 10.1099/jmm.0.033910-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Spacer sequences of 42 and 127 bp, respectively, between the ISEcp1 insertion sequence and bla(CTX-M) have been observed in Klebsiella pneumoniae. However, it is not known whether different spacers upstream of bla(CTX-M) and a promoter within the 127 bp spacer influence cephalosporin resistance. Three recombinant plasmids with different spacers and with or without ISEcp1 were constructed to compare bla(CTX-M-3) expression and susceptibility to cephalosporins. Our experiment revealed enhanced bla(CTX-M-3) expression and a relatively high level resistance to cefotaxime and cefepime in recombinant plasmid IS42CTX-M-3, which contained ISEcp1 and the 42 bp spacer. A minor difference in bla(CTX-M-3) expression was observed in recombinants IS127CTX-M-3 and 127CTX-M-3, which contained a 127 bp spacer with or without ISEcp1, respectively. In conclusion, the promoter within ISEcp1 and a shorter spacer (42 bp but not 127 bp) between ISEcp1 and bla(CTX-M) are necessary for high-level bla(CTX-M-3) expression.
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Affiliation(s)
- Ling Ma
- Division of Infectious Disease, National Health Research Institutes, Miaoli County, Taiwan, ROC
| | - Leung Kris Siu
- Division of Infectious Disease, National Health Research Institutes, Miaoli County, Taiwan, ROC
| | - Po-Liang Lu
- School of Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Taiwan, ROC.,Department of Internal Medicine and Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Taiwan, ROC
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30
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Abstract
Antibiotic resistance in Gram-negative bacteria is often due to the acquisition of resistance genes from a shared pool. In multiresistant isolates these genes, together with associated mobile elements, may be found in complex conglomerations on plasmids or on the chromosome. Analysis of available sequences reveals that these multiresistance regions (MRR) are modular, mosaic structures composed of different combinations of components from a limited set arranged in a limited number of ways. Components common to different MRR provide targets for homologous recombination, allowing these regions to evolve by combinatorial evolution, but our understanding of this process is far from complete. Advances in technology are leading to increasing amounts of sequence data, but currently available automated annotation methods usually focus on identifying ORFs and predicting protein function by homology. In MRR, where the genes are often well characterized, the challenge is to identify precisely which genes are present and to define the boundaries of complete and fragmented mobile elements. This review aims to summarize the types of mobile elements involved in multiresistance in Gram-negative bacteria and their associations with particular resistance genes, to describe common components of MRR and to illustrate methods for detailed analysis of these regions.
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Affiliation(s)
- Sally R Partridge
- Centre for Infectious Diseases and Microbiology, The University of Sydney, Westmead Hospital, Sydney, NSW 2145, Australia.
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31
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Réjiba S, Mercuri PS, Power P, Kechrid A. Emergence and Dominance of CTX-M-15 Extended Spectrum Beta-Lactamase Among Escherichia coli Isolates from Children. Microb Drug Resist 2011; 17:135-40. [DOI: 10.1089/mdr.2010.0098] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Samia Réjiba
- Département des Sciences Biologiques, Faculté des Sciences de Tunis, Université Tunis El-Manar, Tunis, Tunisia
- Laboratoire de Microbiologie, Hôpital d'Enfants, Tunis, Tunisia
| | - Paola Sandra Mercuri
- Laboratoire de Macromolécules Biologiques, Centre d'Ingénierie des Protéines, Université de Liège, Institut de Chimie B6a, Liège, Sart-Tilman, Belgium
| | - Pablo Power
- Laboratoire de Macromolécules Biologiques, Centre d'Ingénierie des Protéines, Université de Liège, Institut de Chimie B6a, Liège, Sart-Tilman, Belgium
| | - Amel Kechrid
- Laboratoire de Microbiologie, Hôpital d'Enfants, Tunis, Tunisia
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32
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Naseer U, Sundsfjord A. The CTX-M Conundrum: Dissemination of Plasmids andEscherichia coliClones. Microb Drug Resist 2011; 17:83-97. [DOI: 10.1089/mdr.2010.0132] [Citation(s) in RCA: 169] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Umaer Naseer
- Research Group for Host-Microbe Interactions, Department of Medical Biology, University of Tromsø, Tromsø, Norway
| | - Arnfinn Sundsfjord
- Research Group for Host-Microbe Interactions, Department of Medical Biology, University of Tromsø, Tromsø, Norway
- Reference Centre for Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, Tromsø, Norway
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33
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Chen CY, Strobaugh TP, Lindsey RL, Frye JG, Uhlich G. Sequence analysis of a group of low molecular-weight plasmids carrying multiple IS903 elements flanking a kanamycin resistance aph gene in Salmonella enterica serovars. Plasmid 2011; 65:246-52. [PMID: 21324339 DOI: 10.1016/j.plasmid.2011.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 02/01/2011] [Accepted: 02/08/2011] [Indexed: 11/25/2022]
Abstract
A group of low molecular-weight ColE1-like plasmids carrying the aph sequence type aph(ii) from three different Salmonella serovars were sequenced. These plasmids carry two or more copies of IS903 elements, with up to 21bp sequence differences to one another, two of which flank the aph gene. This group of plasmids did not appear to carry any known mobilization genes and instead carry three open reading frames encoding hypothetical proteins of unknown function possibly organized in an operon. The plasmid replication region (RNA I/II--rom) of this plasmid group showed extensive homology to that of pKPN2 plasmid of Klebsiella pneumoniae and pCol-let plasmid of Escherichia coli. Three of the four plasmids had identical sequences, and the fourth had an extra copy of IS903 with target duplication, suggesting a recent divergence in the different Salmonella serovars from a common ancestor.
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Affiliation(s)
- Chin-Yi Chen
- Eastern Regional Research Center, Agricultural Research Service, US Department of Agriculture, 600 E. Mermaid Ln., Wyndmoor, PA 19038, USA.
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34
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Al Sweih N, Al Hashem G, Jamal W, Rotimi V. National surveillance of antimicrobial susceptibility of CTX-M-positive and -negative clinical isolates of Escherichia coli from Kuwait government hospitals. J Chemother 2010; 22:254-8. [PMID: 20685629 DOI: 10.1179/joc.2010.22.4.254] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Antibiotic resistance in Escherichia coli is becoming a complex therapeutic problem. Surveillance programs are valuable tools and offer important information on bacterial resistance trends. This study was undertaken to determine the susceptibility of clinically significant isolates of E. coli obtained from patients admitted to 8 Kuwait government hospitals and to examine how this was influenced by the production of CTX-M extended-spectrum beta-lactamases (ESBLs). The susceptibility of 876 consecutive clinically significant strains of E. coli to 13 antibiotics was determined by Etest. ESBL production was assessed by ESBL-Etest method and the presence of CTX-M beta-lactamases was confirmed by PCR technique. Of the 876 isolates, 604 (69%) were highly non-susceptible to ampicillin with MIC(90 )of >256 microg/ml. Resistance to the 3(rd)-generation cephalosporins ranged from 7.5% in the Maternity hospital to 29% in the Ibn Sina hospital; ciprofloxacin resistance rates ranged from 14% and 40%, respectively. Carbapenems and amikacin demonstrated excellent activity. The minimum inhibitory concentrations (MIC(90)) of cefotaxime, ceftazidime, cefepime and ciprofloxacin were >256, 64, >256 and >32 microg/ml, respectively for CTX-M-positive isolates versus 0.5, 1, 025 and 0.125 microg/ml for CTX-M-negative strains. Frequencies of CTX-M-positive isolates within the cefotaxime MIC ranges of 1-2, 3-8, 9-16 and >16 microg/ml were 0, 4, 15 and 81%, respectively. In conclusion, the susceptibility of E. coli to the 3(rd )generation cephalosporins and ciprofloxacin was influenced by the presence of CTX-M ESBL and a high proportion of the CTX-M-producing isolates were in the susceptibility ranges of cefotaxime.
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Affiliation(s)
- N Al Sweih
- Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait
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35
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Abstract
Pantoea stewartii SW2 contains 13 plasmids. One of these plasmids, pSW200, has a replicon that resembles that of ColE1. This study demonstrates that pSW200 contains a 9-bp UP element, 5'-AAGATCTTC, which is located immediately upstream of the -35 box in the RNAII promoter. A transcriptional fusion study reveals that substituting this 9-bp sequence reduces the activity of the RNAII promoter by 78%. The same mutation also reduced the number of plasmid copies from 13 to 5, as well as the plasmid stability. When a similar sequence in a ColE1 derivative, pYCW301, is mutated, the copy number of the plasmid also declines from 34 to 16 per cell. Additionally, inserting this 9-bp sequence stabilizes an unstable pSW100 derivative, pSW142K, which also contains a replicon resembling that of ColE1, indicating the importance of this sequence in maintaining the stability of the plasmid. In conclusion, the 9-bp sequence upstream of the -35 box in the RNAII promoter is required for the efficient synthesis of RNAII and maintenance of the stability of the plasmids in the ColE1 family.
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36
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Characterization of small ColE1-like plasmids conferring kanamycin resistance in Salmonella enterica subsp. enterica serovars Typhimurium and Newport. Plasmid 2010; 63:150-4. [DOI: 10.1016/j.plasmid.2009.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Revised: 12/17/2009] [Accepted: 12/21/2009] [Indexed: 11/17/2022]
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37
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A novel IS26 structure surrounds bla
CTX-M genes in different plasmids from German clinical Escherichia coli isolates. J Med Microbiol 2010; 59:580-587. [DOI: 10.1099/jmm.0.016188-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This report focuses on the molecular characterization of 22 extended-spectrum β-lactamase-producing Escherichia coli isolates collected in a German university hospital during a period of 9 months in 2006. Relationship analysis of clinical isolates was done via PFGE, multilocus sequence typing, plasmid profiling and additionally PCR for bla
ESBL detection and determination of phylogroups. After conjugal transfer, plasmid isolation and subsequent PCR for bla
ESBL detection and determination of incompatibility groups were performed. Using one-primer walking, up to 3600 bp upstream and downstream of different bla
CTX-M genes could be sequenced. β-Lactamases found were TEM-1 (n=14), SHV-5 (n=1) and a wide variety of CTX-M types (n=21), i.e. CTX-M-15 (n=12), CTX-M-1 (n=4), CTX-M-14 (n=2), CTX-M-9 (n=1), CTX-M-3 (n=1) and one new type, CTX-M-65 (n=1). In 18 isolates, bla
ESBL genes were located on conjugative plasmids of sizes between 40 and 180 kbp belonging to incompatibility groups FII (n=9), N (n=5) and I1 (n=4). bla
CTX-M was found to be associated with the common elements ISEcp1, IS26 and IS903-D, but with unusual spacer sequences for ISEcp1 in two isolates. These insertion sequences, connected to bla
CTX-M as well as other genes, were located between two IS26 elements in a configuration that has not yet been described. The results reveal the emergence of bla
ESBL, predominantly bla
CTX-M, located on different plasmids harboured by genotypically different E. coli strains. The identical gene arrangement in the bla
CTX-M neighbourhood in plasmids of different incompatibility groups indicates a main role of IS26 in distribution of mobile resistance elements between different plasmids.
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38
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Survey for β-lactamase among bacterial isolates from Guangzhou, China hospitals between 2005–2006. J Antibiot (Tokyo) 2010; 63:225-9. [DOI: 10.1038/ja.2010.23] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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39
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40
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Comparative in vitro activity of tigecycline and other antimicrobial agents against Shigella species from Kuwait and the United Arab of Emirates. J Infect Public Health 2010; 3:35-42. [DOI: 10.1016/j.jiph.2009.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 10/14/2009] [Accepted: 10/18/2009] [Indexed: 11/21/2022] Open
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41
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Jamal WY, Al Hashem G, Khodakhast F, Rotimi VO. Comparative in vitro activity of tigecycline and nine other antibiotics against gram-negative bacterial isolates, including ESBL-producing strains. J Chemother 2009; 21:261-6. [PMID: 19567345 DOI: 10.1179/joc.2009.21.3.261] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The enterobacteriaceae, especially Escherichia coli and Klebsiella spp., as well as Acinetobacter spp., are important agents of nosocomial infections in hospitalized patients. A total of 460 Gram-negative bacteria (GNb), were investigated for their susceptibility to tigecycline and 9 other antibiotics by the etest. ESBL production was inferred from ESBL etest phenotypes. All the GNb, including the ESBL-producers, were susceptible to tigecycline with MIC(90 )ranges of 0.25 to 2 microg/ml. Imipenem and meropenem were very active against ESBL and non-ESBL producers; mean MIC(90)s of 0.19 and 0.09 microg/ml and 0.05 microg/ml and 0.02 microg/ml, respectively. The MIC(90)s of imipenem and meropenem for the Acinetobacter spp. were 16 and >32 microg/ml, respectively with resistance rates of 64.3 and 66.1%. ESBL production was detected in 62% and 82.1% of the E. coli and K. pneumoniae isolates, respectively. Resistance to ciprofloxacin was higher among the ESBL-producing strains of E. coli and K. pneumoniae than the non-ESBL producers. Comparatively, tigecycline had excellent in vitro activities against ESBL-producing enterobacteriaceae and demonstrated superior activity against Acinetobacter spp. Increasing ESBL production and resistance to ciprofloxacin and gentamicin in enterobacteriaceae require careful selection of empirical therapy. Tigecycline holds promise as an alternative choice of therapy for infections caused by ESBL-producing isolates and multi-drug resistant Acinetobacter spp.
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Affiliation(s)
- W Y Jamal
- Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait
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42
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43
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Characterization of conjugative plasmids carrying antibiotic resistance genes encoding 16S rRNA methylase, extended-spectrum beta-lactamase, and/or plasmid-mediated AmpC beta-lactamase. J Microbiol 2009; 47:68-75. [PMID: 19229493 DOI: 10.1007/s12275-008-0158-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 11/03/2008] [Indexed: 10/21/2022]
Abstract
In this study, we identified extended-spectrum beta-lactamase (ESBL) and plasmid-mediated AmpC beta-lactamase which were associated with 16S rRNA methylase gene on the conjugative plasmid. Among 82 clinical isolates of Enterobacteriaceae that carry 16S rRNA methylase gene (64 strains, armA, and 18 strains, rmtB), bla(SHV-12) was detected either alone or combined with bla(DHA-1), bla(CTX-M-3), and bla(CTX-M-14) in 30 strains carrying armA and 6 strains carrying rmtB. The bla(CTX-M-3) was detected in 13 of 64 strains carrying armA but no strains carrying rmtB. Whereas bla(CTX-M-14) was detected in 15 of 18 strains carrying rmtB but only 2 of 64 strains carrying armA. Overall, bla(SHV-12) and bla(CTX-M-14) was the most common ESBL gene which was associated with armA and rmtB, respectively. In addition, we found that bla(CTX-M-3) localized with armA on the same IncL/M plasmid and bla(CTX-M-14) localized with rmtB on the same IncA/C plasmid. Restriction fragment length polymorphism of conjugative plasmids and pulsed-field gel electrophoresis of genomic DNAs revealed that intercellular horizontal transfer of conjugative plasmid and clonal transmission have been occurred at the same time.
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44
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CMY-31 and CMY-36 cephalosporinases encoded by ColE1-like plasmids. Antimicrob Agents Chemother 2008; 53:1256-9. [PMID: 19104021 DOI: 10.1128/aac.01284-08] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two CMY-2 derivatives, CMY-31 (Gln(215)-->Arg) from Salmonella enterica serotype Newport and CMY-36 (Ala(77)-->Cys and Gln(193)-->Glu) from Klebsiella pneumoniae, were characterized. Both cephalosporinases functionally resembled CMY-2. bla(CMY) alleles occurred as parts of a putative transposon comprising ISEcp1B and a Citrobacter freundii-derived sequence carried by ColE1-like plasmids similar to CMY-5-encoding pTKH11 from Klebsiella oxytoca.
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45
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Nationwide survey of CTX-M-type extended-spectrum beta-lactamases among Klebsiella pneumoniae isolates in Slovenian hospitals. Antimicrob Agents Chemother 2008; 53:287-91. [PMID: 19001116 DOI: 10.1128/aac.00746-08] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Among 177 extended-spectrum beta-lactamase-producing Klebsiella pneumoniae isolates collected from 11 Slovenian hospitals in 2005 and 2006, 60 (34%), from eight hospitals, harbored genes for CTX-M enzymes, with bla(CTX-M-15) detected by sequencing. These 60 isolates comprised 11 pulsed-field gel electrophoresis-defined strains, with several clusters of closely related isolates. Plasmids encoding CTX-M-15 enzyme were highly transmissible.
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46
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Bae IK, Lee YH, Jeong HJ, Hong SG, Lee SH, Jeong SH. A novel blaCTX-M-14 gene-harboring complex class 1 integron with an In4-like backbone structure from a clinical isolate of Escherichia coli. Diagn Microbiol Infect Dis 2008; 62:340-2. [DOI: 10.1016/j.diagmicrobio.2008.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 06/16/2008] [Accepted: 06/25/2008] [Indexed: 10/21/2022]
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47
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Rotimi VO, Jamal W, Pal T, Sovenned A, Albert MJ. Emergence of CTX-M-15 type extended-spectrum beta-lactamase-producing Salmonella spp. in Kuwait and the United Arab Emirates. J Med Microbiol 2008; 57:881-886. [PMID: 18566147 DOI: 10.1099/jmm.0.47509-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cephalosporins are major antimicrobials used to treat serious Salmonella infections. However, their effectiveness is being compromised by the emergence of extended-spectrum beta-lactamases (ESBLs). The genetic determinants encoding ESBL in Salmonella spp. isolated from patients in Kuwait and United Arab Emirates (UAE) were studied over a 2 year period. Out of a total of 407 isolates, 116 isolates possessed the resistance phenotypes consistent with possible ESBL production. Of these, 69 (59.5 %) were ESBL positive. PCR and sequencing were used to determine the genetic determinant(s) responsible for ESBL phenotypes. A total of 14 (12.1 %) and 29 (24.6 %) isolates were CTX-M-15 ESBL producers and TEM producers, respectively. Ten CTX-M-15 producers carried the insertion sequence ISEcpI gene. PFGE analysis revealed identical profiles in 4 of the 13 Kuwaiti strains. This study reports the presence of the bla(CTX-M-15) gene in Salmonella spp. and Salmonella enterica serotype Typhi from Kuwait and UAE for what is believed to be the first time. This is of great concern as the gene is also found in association with the ISEcpI gene, which may easily facilitate its spread. These isolates originated mostly from non-Kuwaiti Arabs rather than from people of Asian origin.
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Affiliation(s)
- Vincent O Rotimi
- Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait
| | - Wafaa Jamal
- Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait
| | - Tibor Pal
- Department of Microbiology & Immunology, Pecs University, Pecs, Hungary
| | - Agnes Sovenned
- Department of Microbiology & Immunology, Pecs University, Pecs, Hungary
| | - M John Albert
- Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait
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48
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Gołebiewski M, Kern-Zdanowicz I, Zienkiewicz M, Adamczyk M, Zylinska J, Baraniak A, Gniadkowski M, Bardowski J, Cegłowski P. Complete nucleotide sequence of the pCTX-M3 plasmid and its involvement in spread of the extended-spectrum beta-lactamase gene blaCTX-M-3. Antimicrob Agents Chemother 2007; 51:3789-95. [PMID: 17698626 PMCID: PMC2151408 DOI: 10.1128/aac.00457-07] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we report the nucleotide sequence of pCTX-M3, a highly conjugative plasmid that is responsible for the extensive spread of the gene coding for the CTX-M-3 extended-spectrum beta-lactamase in clinical populations of the family Enterobacteriaceae in Poland. The plasmid belongs to the IncL/M incompatibility group, is 89,468 bp in size, and carries 103 putative genes. Besides bla(CTX-M-3), it also bears the bla(TEM-1), aacC2, and armA genes, as well as integronic aadA2, dfrA12, and sul1, which altogether confer resistance to the majority of beta-lactams and aminoglycosides and to trimethoprim-sulfamethoxazole. The conjugal transfer genes are organized in two blocks, tra and trb, separated by a spacer sequence where almost all antibiotic resistance genes and multiple mobile genetic elements are located. Only bla(CTX-M-3), accompanied by an ISEcp1 element, is placed separately, in a DNA fragment previously identified as a fragment of the Kluyvera ascorbata chromosome. On the basis of sequence analysis, we speculate that pCTX-M3 might have arisen from plasmid pEL60 from plant pathogen Erwinia amylovora by acquiring mobile elements with resistance genes. This suggests that plasmids of environmental bacterial strains could be the source of those plasmids now observed in bacteria pathogenic for humans.
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Affiliation(s)
- M Gołebiewski
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland
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Bae IK, Lee YN, Lee WG, Lee SH, Jeong SH. Novel complex class 1 integron bearing an ISCR1 element in an Escherichia coli isolate carrying the blaCTX-M-14 gene. Antimicrob Agents Chemother 2007; 51:3017-9. [PMID: 17517851 PMCID: PMC1932499 DOI: 10.1128/aac.00279-07] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This work identifies an ISCR1-related bla(CTX-M-14) gene, which has never been reported before, from a clinical isolate of Escherichia coli. The bla(CTX-M-14) gene was preceded by an ISCR1 element that was followed by a class 1 integron containing three different insert gene cassettes, i.e., dfrA12, orfF, and aadA2.
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Affiliation(s)
- Il Kwon Bae
- Research Institute for Antimicrobial Resistance and Department of Laboratory Medicine, Kosin University College of Medicine, 34 Amnam-Dong, Suh-Gu, Busan, Republic of Korea
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Pitout JDD, Hamilton N, Church DL, Nordmann P, Poirel L. Development and clinical validation of a molecular diagnostic assay to detect CTX-M-type beta-lactamases in Enterobacteriaceae. Clin Microbiol Infect 2007; 13:291-7. [PMID: 17391384 DOI: 10.1111/j.1469-0691.2006.01645.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Enterobacterial isolates producing CTX-M beta-lactamases have recently emerged worldwide in the community and hospital settings. Because of the significant public health implications, the spread of organisms producing CTX-M enzymes merits close monitoring with enhanced surveillance efforts. A molecular diagnostic assay using two different sets of primers simultaneously for the detection of all bla(CTX-M)-like beta-lactamase genes was developed. This assay repeatedly demonstrated 100% sensitivity, specificity and positive and negative predictive values for detecting different CTX-M enzymes in well-characterised strains that included producers of VEB-, TEM- and SHV-type extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC enzymes. The majority (132/240; 55%) of ESBL-producing enterobacterial isolates recovered in the Calgary Health Region during 2003 and 2004 were positive for bla(CTX-M) genes, including 81 (61%) positive for the CTX-M-9 group, 49 (37%) for the CTX-M-1 group, and two (2%) for the CTX-M-2 group. The CTX-M-specific PCR assay was reproducible and easy to use. It can be introduced in a clinical or reference laboratory to track and monitor the spread of organisms producing CTX-M enzymes in the community and hospital settings.
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Affiliation(s)
- J D D Pitout
- Division of Microbiology, Calgary Laboratory Services, Calgary, Alberta, Canada.
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