J Med Microbiol 57 (2008), 776-783; DOI: 10.1099/jmm.0.47739-0
© 2008 Society for General Microbiology
ISSN 1473-5644
Effect of sub-MIC concentrations of metronidazole, vancomycin, clindamycin and linezolid on toxin gene transcription and production in Clostridium difficile
Michael Gerber1,
,
Christiane Walch1,
Birgit Löffler1,
,
Kristin Tischendorf1,
Udo Reischl2 and
Grit Ackermann1,
1 Institute of Medical Microbiology and Epidemiology of Infectious Diseases, University of Leipzig, Liebigstraße 24, 04103 Leipzig, Germany
2 Institute of Medical Microbiology and Hygiene, University Hospital of Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany
Correspondence
Michael Gerber
michael.gerber{at}medizin.uni-leipzig.de
Received 31 October 2007
Accepted 11 February 2008
Clostridium difficile is the major cause of hospital-acquired infectious diarrhoea. Several antimicrobials are known to induce and promote C. difficile-associated diarrhoea (CDAD). The impact of metronidazole (MTR), vancomycin (VAN), clindamycin (CLI) and linezolid (LZD) on growth, toxin gene transcription and toxin production in C. difficile was investigated. Four C. difficile strains were grown with and without sub-MIC concentrations of MTR, VAN, CLI and LZD (0.5x MIC) and growth was measured by colony counts. Toxin production was detected using ELISA (for toxin A) and a cytotoxicity assay (for toxin B) in culture supernatants and also in sonicated cells. Real-time PCR was used to measure transcription of the toxin A and B genes. The aim of this work was to combine analysis of toxin A and B production by ELISA or cell culture assay with transcriptomic analysis. The four strains showed similar growth and different levels of toxin production in the absence of antibiotics. An antibiotic-free control showed toxin production at a late stage when the plateau phase of bacterial growth was reached, whereas antibiotic-exposed strains showed earlier toxin production. All of the antibiotics used except CLI increased the transcription rate of toxin genes. The findings of this study show that sub-MIC concentrations of antibiotics can cause changes in gene transcription of the major virulence factors of C. difficile. This study describes a new method for transcriptomic analysis of toxin genes in C. difficile.
Abbreviations: CDAD, Clostridium difficile-associated diarrhoea; CLI, clindamycin; LZD, linezolid; MTR, metronidazole; PMC, pseudomembranous colitis; VAN, vancomycin.
Present address: Institute of Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Paul-List-Straße 13–15, 04103 Leipzig, Germany.
Present address: Department for Molecular Cell Therapy, University of Leipzig, Deutscher Platz 5, 04103 Leipzig, Germany.
This article has been cited by other articles:

|
 |

|
 |
 
J. L. Martinez
Antibiotics and Antibiotic Resistance Genes in Natural Environments
Science,
July 18, 2008;
321(5887):
365 - 367.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
I. R. Poxton
Clostridium difficile
J. Med. Microbiol.,
June 1, 2008;
57(6):
683 - 684.
[Full Text]
[PDF]
|
 |
|
Copyright © 2008 Society for General Microbiology.