| Title |
Modulation of Secreted Virulence Factor Genes by Subinhibitory Concentrations of Antibiotics in Pseudomonas aeruginosa |
| Author |
Lixin Shen1, Ying Shi1, Dan Zhang1, Jinhua Wei1, Michael G. Surette2, and Kangmin Duan1,2* |
| Address |
1Molecular Microbiology Laboratory, Ministry of Education Key Laboratory of Resource Biology and Biotechnology in Western China, Northwest University, Xi’an 710069, P. R. China, 2Department of Microbiology and Infectious Diseases, Faculty of Medicine, University of Calgary, 3330 Hospital Dr. Calgary, AB T2N 4N1, Canada |
| Bibliography |
Journal of Microbiology, 46(4),441-447, 2008,
|
| DOI |
|
| Key Words |
Pseudomonas aeruginosa, virulence factors, subinhibitory concentration of antibiotics, gene regulation |
| Abstract |
Recent studies have shown that subinhibitory antibiotics play important roles in regulating bacterial genes including virulence factor genes. In this study, the expression of 13 secreted virulence related gene clusters of Pseudomonas aeruginosa, an important opportunistic pathogen, was examined in the presence of subinhibitory concentrations of 4 antibiotics: vancomycin, tetracycline, ampicilin and azithromycin. Activation of gene expression was observed with phzA1, rhlAB, phzA2, lasB, exoY, and exoS. Subinhibitory concentrations of vancomycin resulted in more than 10-fold increase of rhlAB and phzA2 transcription. Both rhamnolipid production and pyocyanin production were significantly elevated, correlating phenotypes with the increased transcription. P. aeruginosa swarming and swimming motility also increased. Similar results were observed with subinhibitory tetracycline, azithromycin and ampicillin. These results indicate that the antibiotics at low concentrations can up-regulate virulence factors and therefore influence bacterial
pathogenesis. |
