JAC Advance Access originally published online on July 26, 2005
Journal of Antimicrobial Chemotherapy 2005 56(3):485-490; doi:10.1093/jac/dki262
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Molecular basis of resistance to trimethoprim, chloramphenicol and sulphonamides in Bordetella bronchiseptica
Institut für Tierzucht, Bundesforschungsanstalt für Landwirtschaft (FAL), Höltystrasse 10, 31535 Neustadt-Mariensee, Germany
Received 25 May 2005; returned 23 June 2005; revised 24 June 2005; accepted 25 June 2005
* Corresponding author. Tel: +49-5034-871-241; Fax: +49-5034-871-246; E-mail: stefan.schwarz{at}fal.de
Objectives: To date, little is known about the molecular basis of antimicrobial resistance in Bordetella bronchiseptica, an important respiratory tract pathogen in pigs, dogs and cats. The aim of this study was to identify genes coding for trimethoprim resistance present in porcine B. bronchiseptica and to determine their localization, transferability and association with other resistance genes.
Methods: Six B. bronchiseptica isolates with elevated MICs of trimethoprim were investigated by PCR for the presence of trimethoprim resistance genes and their association with class 1 integrons. The amplicons obtained were cloned and sequenced. Plasmid localization of these integrons was confirmed by transformation and conjugation. Isolates carrying the same integron were compared for their genetic relatedness by XbaI and SpeI pulsed-field gel electrophoresis (PFGE).
Results: Five B. bronchiseptica isolates carried a class 1 integron with two gene cassettes, one carrying the trimethoprim resistance gene dfrA1 and the other the chloramphenicol resistance gene catB3. This integron was present on a common conjugative plasmid in four of the five isolates and on the chromosome in the remaining isolate. All five B. bronchiseptica isolates proved to be related on the basis of their PFGE patterns. Another isolate had a class 1 integron with a dfrB1 and a catB2 cassette on a structurally different conjugative plasmid. The sulphonamide resistance gene sul1 was detected in the 3'-conserved segment of both types of integrons.
Conclusions: This is the first report of trimethoprim, chloramphenicol and sulphonamide resistance genes and class 1 integrons in B. bronchiseptica isolates.
Keywords: dfrA1 , dfrB1 , catB2 , catB3 , sul1 , class 1 integrons , conjugation , respiratory tract infections
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  A. Moodley and L. Guardabassi Transmission of IncN Plasmids Carrying blaCTX-M-1 between Commensal Escherichia coli in Pigs and Farm Workers Antimicrob. Agents Chemother., April 1, 2009; 53(4): 1709 - 1711. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Kadlec and S. Schwarz Analysis and distribution of class 1 and class 2 integrons and associated gene cassettes among Escherichia coli isolates from swine, horses, cats and dogs collected in the BfT-GermVet monitoring study J. Antimicrob. Chemother., September 1, 2008; 62(3): 469 - 473. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Kadlec, I. Wiegand, C. Kehrenberg, and S. Schwarz Studies on the mechanisms of {beta}-lactam resistance in Bordetella bronchiseptica J. Antimicrob. Chemother., March 1, 2007; 59(3): 396 - 402. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Kadlec, C. Kehrenberg, and S. Schwarz Efflux-mediated resistance to florfenicol and/or chloramphenicol in Bordetella bronchiseptica: identification of a novel chloramphenicol exporter J. Antimicrob. Chemother., February 1, 2007; 59(2): 191 - 196. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Kehrenberg, S. Friederichs, A. de Jong, G. B. Michael, and S. Schwarz Identification of the plasmid-borne quinolone resistance gene qnrS in Salmonella enterica serovar Infantis J. Antimicrob. Chemother., July 1, 2006; 58(1): 18 - 22. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Kadlec, C. Kehrenberg, and S. Schwarz tet(A)-mediated tetracycline resistance in porcine Bordetella bronchiseptica isolates is based on plasmid-borne Tn1721 relics J. Antimicrob. Chemother., July 1, 2006; 58(1): 225 - 227. [Full Text] [PDF]
|
|