Molecular characterization of an RTX toxin determinant from Actinobacillus suis.
AUTOR(ES)
Burrows, L L
RESUMO
RTX cytolysins are a family of calcium-dependent, pore-forming, secreted toxins found in a variety of gram-negative bacteria. The prototypical member of this family is the alpha-hemolysin of Escherichia coli. The RTX genetic determinants from seven members of the family Pasteurellaceae, Pasteurella haemolytica, Actinobacillus actinomycetemcomitans, and A. pleuropneumoniae serotypes 1,5,7, and 9 were previously cloned and sequenced. Using the leukotoxin determinant from P. haemolytica serotype A1 as a probe, we detected the presence of RTX-type determinants in Actinobacillus suis, A. equuli, and A. lignieresii of the family Pasteurellaceae. All three species elaborate proteins of approximately 104 to 110 kDa that are recognized by polyclonal antisera against the 104-kDa hemolysin of A. pleuropneumoniae serotype 1. An RTX determinant of A. suis isolate 3714 was cloned and sequenced and was found to be almost identical to the RTX determinant of A. pleuropneumoniae serotypes 5 and 9. In addition, the determinant is not composed of four contiguous genes, as had been reported for most other RTX determinants; instead, the genes encoding the two proteins responsible for secretion of the toxin are at a locus distinct from that containing the toxin structural and activation genes.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=257139Documentos Relacionados
- Production of Apx toxins by field strains of Actinobacillus pleuropneumoniae and Actinobacillus suis.
- Cloning and characterization of the Actinobacillus pleuropneumoniae-RTX-toxin III (ApxIII) gene.
- Characterization of PaxA and Its Operon: a Cohemolytic RTX Toxin Determinant from Pathogenic Pasteurella aerogenes
- Characterization of an RTX toxin from enterohemorrhagic Escherichia coli O157:H7.
- Genetic map of the Actinobacillus pleuropneumoniae RTX-toxin (Apx) operons: characterization of the ApxIII operons.
