Atypical cpb2 Genes, Encoding Beta2-Toxin in Clostridium perfringens Isolates of Nonporcine Origin
AUTOR(ES)
Jost, B. Helen
FONTE
American Society for Microbiology
RESUMO
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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=538998Documentos Relacionados
- Molecular detection and characterization of cpb2 gene in Clostridium perfringens isolates from healthy and diseased chickens
- Purification of beta-toxin from Clostridium perfringens type C.
- The virR/virS locus regulates the transcription of genes encoding extracellular toxin production in Clostridium perfringens.
- Highly Conserved Alpha-Toxin Sequences of Avian Isolates of Clostridium perfringens
- Evaluation of toxin-antitoxin genes, antibiotic resistance, and virulence genes in Pseudomonas aeruginosa isolates