J Med Microbiol 56 (2007), 329-335; DOI: 10.1099/jmm.0.46931-0
© 2007 Society for General Microbiology
ISSN 1473-5644
Variant forms of the binary toxin CDT locus and tcdC gene in Clostridium difficile strains
Barbara Geric Stare1,2,
Michel Delmée2 and
Maja Rupnik3
1 Agricultural Institute of Slovenia, Hacquetova 17, Ljubljana 1000, Slovenia
2 Université Catholique de Louvain, Faculté de Médicine, Unité de Microbiologie, Avenue Hippocrate 54 90, B-1200 Brussels, Belgium
3 Institute of Public Health Maribor and University of Maribor, Medical Faculty, Slomskov trg 15, 2000 Maribor, Slovenia
Correspondence
Maja Rupnik
maja.rupnik{at}uni-mb.si
Received 6 September 2006
Accepted 6 November 2006
Variability in the genes for toxin A, toxin B and other pathogenicity locus regions is well known and is the basis for the distribution of Clostridium difficile strains into variant toxinotypes. Previous data have indicated that some C. difficile strains have a non-functional truncated form of the binary toxin (CDT) locus. This study analysed variability in the CDT locus and the presence of deleted tcdC genes in C. difficile strains. A total of 146 strains were screened, including known variant toxinotypes and non-variant A+B+ (toxinotype 0) and AB C. difficile strains. In all of the strains studied, only two forms of the CDT locus were found: a full-length 4.3 kb fragment encoding the functional binary toxin or a truncated 2.3 kb fragment. Whilst the full-length CDT locus was found almost exclusively in variant toxinotypes, the truncated form was detected in 79 % of toxinotype 0 strains. Non-toxinogenic AB strains with a truncated version were not found and only rarely possessed the full-length CDT locus (ABCDT+ strains). Four different forms of the tcdC gene were found; three represented deleted versions and typically were found in toxinotypes IIIVII, XI, XIVXVI and XXIV.
Abbreviations: LCT, large clostridial toxin; PaLoc, pathogenicity locus; TcdA, toxin A; TcdB, toxin B.
This article has been cited by other articles:

|
 |

|
 |
 
G. P. Carter, D. Lyras, D. L. Allen, K. E. Mackin, P. M. Howarth, J. R. O'Connor, and J. I. Rood
Binary Toxin Production in Clostridium difficile Is Regulated by CdtR, a LytTR Family Response Regulator
J. Bacteriol.,
October 15, 2007;
189(20):
7290 - 7301.
[Abstract]
[Full Text]
[PDF]
|
 |
|
Copyright © 2007 Society for General Microbiology.