JAC Advance Access originally published online on June 21, 2005
Journal of Antimicrobial Chemotherapy 2005 56(2):403-406; doi:10.1093/jac/dki210
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
tet(L)-mediated tetracycline resistance in bovine Mannheimia and Pasteurella isolates
1 Institut für Tierzucht, Bundesforschungsanstalt für Landwirtschaft (FAL), Höltystr. 10, 31535 Neustadt-Mariensee, Germany; 2 Department of Obstetrics, Reproduction and Herd Health, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium; 3 Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
Received 28 April 2005; returned 26 May 2005; revised 27 May 2005; accepted 27 May 2005
* Corresponding author. Tel: +49-5034-871-241; Fax: +49-5034-871-246; E-mail: stefan.schwarz{at}fal.de
Objectives: Tetracycline-resistant Mannheimia and Pasteurella isolates, which were negative for the tetracycline resistance genes (tet) commonly detected among these bacteria, were investigated for other tet genes present and their location.
Methods: Mannheimia and Pasteurella isolates were investigated for their MICs of tetracycline and their plasmid content. Identification of tet genes was achieved by PCR. Plasmids mediating tetracycline resistance were identified by transformation and hybridization experiments. Plasmid pCCK3259 from Mannheimia haemolytica was sequenced completely and analysed for its structure and organization.
Results: All tetracycline-resistant isolates carried the gene tet(L) either on plasmids or on the chromosome. Two M. haemolytica isolates and one Mannheimia glucosida isolate harboured a common 5.3 kb tet(L) plasmid, designated pCCK3259. This plasmid was similar to the tet(B)-carrying tetracycline resistance plasmid pHS-Tet from Haemophilus parasuis and the streptomycin/spectinomycin resistance plasmid pCCK647 from Pasteurella multocida in the parts coding for mobilization functions. The tet(L) gene was closely related to that of the Geobacillus stearothermophilus plasmid pTB19. However, the translational attenuator responsible for the tetracycline-inducible expression of tet(L) was missing in plasmid pCCK3259. A recombination site was identified downstream of tet(L), which might explain the integration of the tet(L) gene region into a basic pCCK3259 replicon.
Conclusion: A tet(L) gene was shown for the first time to be responsible for tetracycline resistance in Mannheimia and Pasteurella isolates. This report demonstrates a lateral transfer of a tetracycline efflux gene in Gram-negative bovine respiratory tract pathogens, probably originating from Gram-positive bacteria.
Keywords: respiratory tract pathogens , antimicrobial resistance , gene transfer , recombination , cattle
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  S. K. P. Lau, G. K. M. Wong, M. W. S. Li, P. C. Y. Woo, and K.-y. Yuen Distribution and molecular characterization of tetracycline resistance in Laribacter hongkongensis J. Antimicrob. Chemother., March 1, 2008; 61(3): 488 - 497. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Blanco, C. B. Gutierrez-Martin, E. F. Rodriguez-Ferri, M. C. Roberts, and J. Navas Distribution of Tetracycline Resistance Genes in Actinobacillus pleuropneumoniae Isolates from Spain Antimicrob. Agents Chemother., February 1, 2006; 50(2): 702 - 708. [Abstract] [Full Text] [PDF]
|
|