pISSN 2093-2340   eISSN 2092-6448
Indexed in ESCI, PubMed, Scopus, DOAJ and more
Open Access, Peer-reviewed
    Infect Chemother. 2009 May-Jun;41(3):165-173. Korean.
    Published online Jun 30, 2009.
    https://doi.org/10.3947/ic.2009.41.3.165
    Copyright © 2009 The Korean Society of Infectious Diseases and The Korean Society for Chemotherapy
    Original Article

    Detection and Characterization of Integrons in Nontyphoid Salmonella Clinical Isolates

    Jung Eun Lee,1,2 Su Jin Park,1,2 Sung Han Kim, M.D.,1,2 Mi-Na Kim, M.D.,3 Nam Yong Lee, M.D.,4 Bok Kwon Lee, Ph.D.,5 Sang-Oh Lee, M.D.,1,2 Yang Soo Kim, M.D.,1,2 Jun-Hee Woo, M.D.,1,2 and Sang-Ho Choi, M.D.1,2
      • 1Center for Antimicrobial Resistance and Microbial Genomics, University of Ulsan, Seoul, Korea.
      • 2Department of Infectious Diseases, Asan Medical Center, Seoul, Korea.
      • 3Department of Laboratory Medicine, University of Ulsan College of Medicine, Seoul, Korea.
      • 4Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
      • 5Division of Enteric Bacterial Infection, Korean Center for Disease Control and Prevention, Seoul, Korea.
    • Correspondence author: Sang-Ho Choi, M.D. Department of Infectious Diseases, Asan Medical Center, Asanbyeongwon-gil 86, Songpa-gu, Seoul 138-736, Korea. Tel: +82-2-3010-3304, Fax: +82-2-3010-6970, Email: sangho@amc.seoul.kr
    Received February 23, 2009; Accepted March 24, 2009.

    This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

    Abstract

    Background

    Nontyphoid Salmonella (NTS) is a leading cause of human food-borne enteritiS. It has been known that integron, a naturally occurring gene capture and expression element, plays an important role in the development and dissemination of multidrug-resistance. In this study, we investigated the prevalences and molecular characteristics of integrons in NTS clinical strains.

    Materials and Methods

    Between 1995-96 and 2000-03, a total 261 NTS clinical strains comprising 39 serotypes were collected from clinical specimens. All strains were serotyped, and the MICs of ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim were determined by agar dilution method. Integrons were detected by PCR amplification of integrase genes, and gene cassettes were determined by PCR and sequencing. Conjugation experiments were performed using E. coli J53 as a recipient. The clonal relationship was analyzed by pulsed-field gel electrophoresis (PFGE).

    Results

    Of the 261 strains tested, class 1 integrons were present in 21 strains (8.0%). Class 2 and class 3 integrons were not found. The integron-positive rate was higher in S. Typhimurium (24.2% [8/33]) than in S. Enteritidis (2.0% [3/153]). Overall rates of antimicrobial resistance were higher in integron-positive strains. dhfr12-orfF-aadA2 gene cassette was detected in 5 strains, aadA2 in 4 strains, dhfr17-orfF-aadA5 in 2 strains, and addA1 in 1 strain. Ten integron-positive transconjugants were successfully selected. Among 8 integron-positive strains of S. Typhimurium, 7 had similar PFGE patterns.

    Conclusion

    This study suggests that integrons are already playing a significant role in antimicrobial resistance in NTS. Continuous monitoring is needed to detect the emergence and spread of integron-mediated antimicrobial resistance.

    Keywords
    Salmonella; Integrons; Antibiotic resistance

    Figures

    Figure 1
    Polymerase chain reaction fragments from the cassette regions of class 1 integrons. M, Molecular weight Marker (1 kb ladder); S. Enteritidis (Lanes 1-3); S. Typhimurium (Lanes 4-11); S. Heidelberg (Lanes 12, 13); S. Montevideo (Lanes 14, 15); S. Dubulin (Lane 16); S. Sinstorf (Lane 17); S. Cuckmere (Lane 18); S. salamae (Lane 19); S. Othmarschen (Lane 20); S. Haifa (Lane 21).

    Figure 2
    Pulsed-field gel electrophoresis patterns of chromosomal DNA restriction fragments resolved in 1.0% Seakem Gold agarose in 0.5×TBE buffer for Salmonella DNA digestion with XbaI. M, ladder size marker; S. Enteritidis (Lanes 1-3); S. Typhimurium (Lanes 4-11); S. Heidelberg (Lanes 12,13); S. Montevideo (Lanes 14,15); S. Dubulin (Lane 16); S. Sinstorf (Lane 17); S. salamae (Lane 18); S. Cuckmere (Lane 19); S. Othmarschen (Lane 20); S. Haifa (Lane 21); ND, not deteremind.

    Tables

    Table 1
    Antibiotic Resistance Patterns of 261 Nontyphoid Salmonella strains

    Table 2
    Antibiotic Resistance Patterns According to the Presence or Absence of Integron

    Table 3
    Distribution of Class 1 Integron Gene Cassette and Antibiotic Resistance Patterns of 21 Integron-carrying Strains

    Table 4
    Antibiotic Resistance Patterns and MICs for 10 Conjugated Strains and Their Transconjugants

    References

      1. Ridley A, Threlfall EJ. Molecular epidemiology of antibiotic resistance genes in multiresistant epidemic Salmonella typhimurium DT 104. Microb Drug Resist 1998;4:113–118.
      1. Daly M, Buckley J, Power E, O'Hare C, Cormican M, Cryan B, Wall PG, Fanning S. Molecular characterization of Irish Salmonella enterica serotype typhimurium: detection of class I integrons and assessment of genetic relationships by DNA amplification fingerprinting. Appl Environ Microbiol 2000;66:614–619.
      1. Guerra B, Soto S, Cal S, Mendoza MC. Antimicrobial resistance and spread of class 1 integrons among Salmonella serotypes. Antimicrob Agents Chemother 2000;44:2166–2169.
      1. Lindstedt BA, Heir E, Nygärd I, Kapperud G. Characterization of class I integrons in clinical strains of Salmonella enterica subsp. enterica serovars Typhimurium and Enteritidis from Norwegian hospitals. J Med Microbiol 2003;52:141–149.
      1. Rodríguez I, Rodicio MR, Herrera-León S, Echeita A, Mendoza MC. Class 1 integrons in multidrug-resistant non-typhoidal Salmonella enterica isolated in Spain between 2002 and 2004. Int J Antimicrob Agents 2008;32:158–164.
      1. Lévesque C, Piché L, Larose C, Roy PH. PCR mapping of integrons reveals several novel combinations of resistance genes. Antimicrob Agents Chemother 1995;39:185–191.
      1. Stokes HW, Hall RM. A novel family of potentially mobile DNA elements encoding site-specific gene-integration functions: integrons. Mol Microbiol 1989;3:1669–1683.
      1. Mazel D. Integrons: agents of bacterial evolution. Nat Rev Microbiol 2006;4:608–620.
      1. White PA, McIver CJ, Rawlinson WD. Integrons and gene cassettes in the enterobacteriaceae. Antimicrob Agents Chemother 2001;45:2658–2661.
      1. Sallen B, Rajoharison A, Desvarenne S, Mabilat C. Molecular epidemiology of integron-associated antibiotic resistance genes in clinical isolates of enterobacteriaceae. Microb Drug Resist 1995;1:195–202.
      1. Hall RM, Collis CM. Mobile gene cassettes and integrons: capture and spread of genes by site-specific recombination. Mol Microbiol 1995;15:593–600.
      1. Popoff MY. In: WHO Collaborating Centre for Reference and Research on Salmonella. Paris: Institute Pasteur; 2001. Antigenic formulas of the Salmonella serovars.
      1. Anderson ES, Ward LR, Saxe MJ, de Sa JD. Bacteriophage-typing designations of Salmonella typhimurium. J Hyg (Lond) 1977;78:297–300.
      1. Choi SH, Woo JH, Lee JE, Park SJ, Choo EJ, Kwak YG, Kim MN, Choi MS, Lee NY, Lee BK, Kim NJ, Jeong JY, Ryu J, Kim YS. Increasing incidence of quinolone resistance in human non-typhoid Salmonella enterica isolates in Korea and mechanisms involved in quinolone resistance. J Antimicrob Chemother 2005;56:1111–1114.
      1. Clinical and Laboratory Standards Institute (CLSI). Performance standards for antimicrobial suceptibility testing; eighteenth informational supplement. 2008.
      1. White PA, McIver CJ, Deng Y, Rawlinson WD. Characterisation of two new gene cassettes, aadA5 and dfrA17. FEMS Microbiol Lett 2000;182:265–269.
      1. Tenover FC, Arbeit RD, Goering RV, Mickelsen PA, Murray BE, Persing DH, Swaminathan B. Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis: criteria for bacterial strain typing. J Clin Microbiol 1995;33:2233–2239.
      1. Oh YH, Song MO, Kim MS, Park SG, Lee YK. Detection of antibiotic resistant genes in Salmonella enterica Serovar Typhimurium isolated from food borne patients in Seoul using multiplex-PCR. J Bacteriol Virol 2005;35:183–190.
      1. Sohn CK, Lee JA, Lee DO, Han W, Jung JK. Structural analysis of class I integron gene cassette and assessment of genetic relationships by PFGE of Salmonella enterica Serovar Typhimurium isolated in Gyeongbuk area. Kor J Microbiol 2006;42:12–18.
      1. Kim TE, Kwon HJ, Cho SH, Kim S, Lee BK, Yoo HS, Park YH, Kim SJ. Molecular differentiation of common promoters in Salmonella class 1 integrons. J Microbiol Methods 2007;68:453–457.
      1. Randall LP, Cooles SW, Osborn MK, Piddock LJ, Woodward MJ. Antibiotic resistance genes, integrons and multiple antibiotic resistance in thirty-five serotypes of Salmonella enterica isolated from humans and animals in the UK. J Antimicrob Chemother 2004;53:208–216.
      1. Vo AT, van Duijkeren E, Fluit AC, Wannet WJ, Verbruggen AJ, Maas HM, Gaastra W. Antibiotic resistance, integrons and Salmonella genomic island 1 among non-typhoidal Salmonella serovars in The Netherlands. Int J Antimicrob Agents 2006;28:172–179.
      1. Cameron FH, Groot Obbink DJ, Ackerman VP, Hall RM. Nucleotide sequence of the AAD(2'') amino glycoside adenylyltransferase determinant aadB. Evolutionary relationship of this region with those surrounding aadA in R538-1 and dhfrII in R388. Nucleic Acids Res 1986;14:8625–8635.
      1. Peters ED, Leverstein-van Hall MA, Box AT, Verhoef J, Fluit AC. Novel gene cassettes and integrons. Antimicrob Agents Chemother 2001;45:2961–2964.
      1. Oh JY, Yu HS, Kim SK, Seol SY, Cho DT, Lee JC. Changes in patterns of antimicrobial susceptibility and integron carriage among Shigella sonnei isolates from southwestern Korea during epidemic periods. J Clin Microbiol 2003;41:421–423.
      1. Yu HS, Lee JC, Kang HY, Ro DW, Chung JY, Jeong YS, Tae SH, Choi CH, Lee EY, Seol SY, Lee YC, Cho DT. Changes in gene cassettes of class 1 integrons among Escherichia coli isolates from urine specimens collected in Korea during the last two decades. J Clin Microbiol 2003;41:5429–5433.
      1. Kang HY, Jeong YS, Oh JY, Tae SH, Choi CH, Moon DC, Lee WK, Lee YC, Seol SY, Cho DT, Lee JC. Characterization of antimicrobial resistance and class 1 integrons found in Escherichia coli isolates from humans and animals in Korea. J Antimicrob Chemother 2005;55:639–644.
      1. Bissonnette L, Roy PH. Characterization of In0 of Pseudomonas aeruginosa plasmid pVS1, an ancestor of integrons of multiresistance plasmids and transposons of gram-negative bacteria. J Bacteriol 1992;174:1248–1257.
    MeSH Terms
    Agar
    Ampicillin
    Chloramphenicol
    Drug Resistance, Microbial
    Electrophoresis, Gel, Pulsed-Field
    Enteritis
    Humans
    Integrases
    Integrons
    Polymerase Chain Reaction
    Prevalence
    Salmonella
    Sprains and Strains
    Streptomycin
    Sulfamethoxazole
    Tetracycline
    Trimethoprim
    Metrics
    Share
    Figures
    slide
    slide

    1 / 2

    Tables
    slide
    slide
    slide
    slide

    1 / 4

    PERMALINK