JAC Advance Access originally published online on February 25, 2003
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Journal of Antimicrobial Chemotherapy (2003) 51, 1037-1039
© 2003 The British Society for Antimicrobial Chemotherapy
Correspondence |
Interaction of plasmid and host quinolone resistance
1 Department of Microbiology, School of Medicine, University of Seville, Seville, Spain; 2 Lahey Clinic, Burlington, MA; 3 VA Medical Center, Bedford, MA, USA
Keywords: fluoroquinolone, antimicrobial, Klebsiella pneumoniae, Escherichia coli
Sir,
Resistance to quinolones in Gram-negative bacteria is usually caused by chromosomal mutations that alter the target enzymes DNA gyrase and topoisomerase IV or activate the efflux systems that pump the drugs out of the cytoplasm. Loss of porin channels for drug entry may also contribute to resistance, but is less important. Plasmid-mediated quinolone resistance, long thought not to exist, has recently been discovered.1 Conjugative plasmid pMG252, found in a clinical isolate of Klebsiella pneumoniae, mediates a four- to 16-fold increase in resistance to fluoroquinolones and nalidixic acid, thus facilitating ciprofloxacin MICs as high as 32 mg/L in a K. pneumoniae strain already partially quinolone resistant. In wild-type K. pneumoniae or Escherichia coli strains pMG252 still augmented resistance but only to ciprofloxacin MICs of 0.125–0.25 mg/L, well below the clinical breakpoint for loss of susceptibility. However, from such an E. coli strain carrying pMG252, mutants could be selected with successively higher levels of resistance up to a ciprofloxacin MIC of 4 mg/L.1
The plasmid locus responsible for quinolone resistance is termed qnr. The gene has been cloned and sequenced. It encodes a 218-amino-acid protein that belongs to the pentapeptide repeat family of proteins.2 Purified Qnr has been shown to block inhibition of E. coli DNA gyrase by ciprofloxacin in a cell-free system.2 The objective of the present study was to evaluate the interaction of resistance determined by plasmid pMG252 with defined chromosomal mechanisms of quinolone resistance to gain an insight into how higher levels of resistance could develop.
Strains used in this study are listed in Table 1. Plasmid pMG252 carries qnr, blaFOX-5 and genes for resistance to chloramphenicol, streptomycin, sulphonamide, trimethoprim and mercuric chloride. The AmpC-type ß-lactamase gene blaFOX-5 confers resistance to ceftazidime and other ß-lactams. The plasmid was transferred from E. coli J53 pMG252 into recipient strains by conjugation and selection on minimal medium A lacking methionine and proline required by J53, and containing ampicillin (100 mg/L) or ceftazidime (10 mg/L) for selection. Quinolones were not used to select transconjugants in order to avoid selecting quinolone resistance mutations in recipients.
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The following quinolones were evaluated: ciprofloxacin (Sigma), clinafloxacin (Parke-Davis, Ann Arbor, MI, USA), levofloxacin (Hoechst-Marion-Roussel, Romainville, France), nalidixic acid (Sigma), norfloxacin (Sigma), pefloxacin (Rhône-Poulenc, Paris, France), sparfloxacin (Rhône-Poulenc) and trovafloxacin (Pfizer). Quinolones were tested in the range 0.002–256 mg/L. MICs were determined by microdilution, according to NCCLS guidelines.3 E. coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853 were used as reference strains for quinolone MIC determinations.
Plasmid pMG252 was introduced into E. coli strains with quinolone resistance mutations in genes for DNA gyrase subunits gyrA and gyrB and topoisomerase IV subunit parC. The plasmid was also transferred into E. coli strains with reduced susceptibility to quinolones and other antibiotics because of mutation at the marR regulatory locus. Finally, pMG252 was transmitted to E. coli and K. pneumoniae strains defective in outer membrane porin channels. As shown in Table 1, quinolone resistance increased four to 128 times when plasmid pMG252 was present in every strain, with the exception that nalidixic acid resistance did not change in E. coli gyrB mutants N-24 and N-31. These findings indicate that qnr can supplement resistance due to altered quinolone target enzymes, efflux pump activation or deficiencies in outer membrane porin channels.
The demonstration that plasmid and chromosomal mechanisms for resistance are additive means that plasmids like pMG252 can supplement quinolone resistance in clinical isolates, whatever their mechanisms of resistance, and also that the whole panoply of chromosomal quinolone resistance mutations can be selected in strains with Qnr plasmids as higher level resistant derivatives. In addition, Qnr facilitates selection of quinolone-resistant mutations by raising the level at which they can be selected.1 Plasmids encoding Qnr are thus important both for the low-level resistance they carry and as agents facilitating steps to higher resistance levels.
Acknowledgements
L.M.-M., A.P. and I.G. were supported by a grant from the Fondo de Investigación Sanitaria, Ministerio de Sanidad, Spain (project 00/0242). G.A.J. was supported by a grant from the R.W. Johnson Pharmaceutical Research Institute and Public Health Service Grant AI43312 from the National Institutes of Health.
Footnotes
* Corresponding author. Tel: +34-95-5008287; Fax: +34-95-4377413; E-mail: lmartin{at}us.es 
References
1 . Martínez-Martínez, L., Pascual, A. & Jacoby, G. A. (1998). Quinolone resistance from a transferable plasmid. Lancet 351, 797–9.[CrossRef][ISI][Medline]
2
.
Tran, J. H. & Jacoby, G. A. (2002). Mechanism of plasmid-mediated quinolone resistance. Proceedings of the National Academy of Sciences, USA 99, 5638–42.
3 . National Committee for Clinical Laboratory Standards. (1997). Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically—Fourth Edition: Approved Standard M7-A4. NCCLS, Wayne, PA, USA.
4 . Bachmann, B. J. (1996). Derivations and genotypes of some mutant derivatives of Escherichia coli K-12. In Escherichia coli and Salmonella (Neidhardt, F. C., Ed.), pp. 2460–88. ASM Press, Washington, DC, USA.
5
.
Hooper, D. C., Wolfson, J. S., Souza, K. S., Tung, C., McHugh, G. L. & Swartz, M. N. (1986). Genetic and biochemical characterization of norfloxacin resistance in Escherichia coli. Antimicrobial Agents and Chemotherapy 29, 639–44.
6 . Yamagishi, J., Yoshida, H., Yamayoshi, M. & Nakamura, S. (1986). Nalidixic acid-resistant mutations of the gyrB gene of Escherichia coli. Molecular and General Genetics 204, 367–73.
7
.
Bagel, S., Hüllen, V., Wiedemann, B. & Heisig, P. (1999). Impact of gyrA and parC mutations on quinolone resistance, doubling time, and supercoiling degree of Escherichia coli. Antimicrobial Agents and Chemotherapy 43, 868–75.
8
.
Nikaido, H., Rosenberg, E. Y. & Foulds, J. (1983). Porin channels in Escherichia coli: studies with ß-lactams in intact cells. Journal of Bacteriology 153, 232–40.
9
.
George, A. M. & Levy, S. B. (1983). Amplifiable resistance to tetracycline, chloramphenicol, and other antibiotics in Escherichia coli: involvement of a non-plasmid-determined efflux of tetracycline. Journal of Bacteriology 155, 531–40.
10
.
Tomás, J. M., Benedí, V. J., Ciurana, B. & Jofré, J. (1986). Role of capsule and O antigen in resistance of Klebsiella pneumoniae to serum bactericidal activity. Infection and Immunity 54, 85–9.
11 . Benedí, V. J., Ciurana, B. & Tomás, J. M. (1985). Isolation and characterization of Klebsiella pneumoniae unencapsulated strains. Journal of Clinical Microbiology 27, 82–7.
12
.
Martínez-Martínez, L., García, I., Ballesta, S., Benedí, V. J., Hernández-Allés, S. & Pascual, A. (1998). Energy-dependent accumulation of fluoroquinolones in quinolone-resistant Klebsiella pneumoniae strains. Antimicrobial Agents and Chemotherapy 42, 1850–2.
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