Virulence studies on chromosomal α‐toxin and Θ‐toxin mutants constructed by allelic exchange provide genetic evidence for the essential role of α‐toxin in Clostridium perfringens‐mediated gas gangrene

@article{Awad1995VirulenceSO,
  title={Virulence studies on chromosomal $\alpha$‐toxin and $\Theta$‐toxin mutants constructed by allelic exchange provide genetic evidence for the essential role of $\alpha$‐toxin in Clostridium perfringens‐mediated gas gangrene},
  author={Milena M. Awad and Amy E Bryant and Dennis L. Stevens and Julian I. Rood},
  journal={Molecular Microbiology},
  year={1995},
  volume={15}
}
The pathogenesis of clostridial myonecrosis, or gas gangrene, involves the growth of the anaerobic bacterium Clostridium perfringens in the infected tissues and the elaboration of numerous extracellular toxins and enzymes. The precise role of each of these toxins in tissue invasion and necrosis has not been determined. To enable genetic approaches to be used to study C. perfringens pathogenesis we developed an allelic exchange method which involved the transformation of C. perfringens cells… Expand
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TLDR
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TLDR
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TLDR
The gene encoding perfringolysin O, the thiol-activated hemolysin from Clostridium perfringens, was cloned and expressed in Escherichia coli and the amino-terminal sequence of the pfo gene product was identical with that determined for perfringolsin O purified from C. perfringen, indicating that E. coli correctly removed the signal peptide during secretion. Expand
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A genetically engineered vaccine against the alpha-toxin of Clostridium perfringens protects mice against experimental gas gangrene.
TLDR
Immunization with Cpa247-370 provided protection in a mouse model against at least 10 LD100 doses of C. perfringens type A and confirmed the essential role of this toxin in the pathogenesis of gas gangrene. Expand
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