Affiliation:
1. Department of Veterinary Science and Microbiology, University of Arizona, Tucson, Arizona
Abstract
ABSTRACT
Beta2-toxin, encoded by
cpb2
, is implicated in the pathogenesis of
Clostridium perfringens
enteritis. However,
cpb2
genes from nonporcine
C. perfringens
isolates were not always expressed, at least in vitro. Nucleotide sequencing identified atypical
cpb2
genes with 70.2 to 70.7% DNA identity to previously identified (consensus)
cpb2
. Atypical beta2-toxin displayed 62.3% identity and 80.4% similarity to consensus beta2-toxin. No porcine type C isolates (
n
= 16) and only 3.3% of porcine type A isolates (
n
= 60) carried atypical
cpb2
genes. However, 88.5% of nonporcine isolates carried atypical
cpb2
(
n
= 78), but beta2-toxin was not expressed. Almost half of the nonporcine consensus
cpb2
genes (44.4%) carried a frameshift mutation (
n
= 9), resulting in an absence of beta2-toxin expression. These findings strengthen the role of beta2-toxin in the pathogenesis of enteritis in neonatal pigs. However, the identification of apparently nonexpressed, atypical
cpb2
genes raises the question of whether this protein plays the same role in enteritis in other animal species.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Immunology,Microbiology,Parasitology
Reference13 articles.
1. Bacciarini, L. N., P. Boerlin, R. Straub, J. Frey, and A. Gröne. 2003. Immunohistochemical localization of the Clostridium perfringens β2-toxin in the gastrointestinal tract of horses. Vet. Pathol.40:376-381.
2. Bueschel, D. M., B. H. Jost, S. J. Billington, H. T. Trinh, and J. G. Songer. 2002. Prevalence of cbp2, encoding beta2 toxin, in Clostridium perfringens field isolates: correlation of genotype with phenotype. Vet. Microbiol.94:121-129.
3. Garmory, H. S., N. Chanter, N. P. French, D. Bueschel, J. G. Songer, and R. W. Titball. 2000. Occurrence of Clostridium perfringens β2-toxin amongst animals, determined using genotyping and subtyping PCR assays. Epidemiol. Infect.124:61-67.
4. Gibert, M., C. Jolivet-Reynaud, and M. R. Popoff. 1997. Beta2 toxin, a novel toxin produced by Clostridium perfringens. Gene203:65-73.
5. Prevalence of β2-Toxigenic
Clostridium perfringens
in Horses with Intestinal Disorders