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Molecular Mode of Action of the Large Clostridial Cytotoxins

  • I. Just
  • F. Hofmann
  • K. Aktories
Chapter
Part of the Current Topics in Microbiology and Immunology book series (CT MICROBIOLOGY, volume 250)

Abstract

The large clostridial cytotoxins are a family of functionally and structurally related toxins produced by clostridia comprising Clostridium difficile toxin A and toxin B, Clostridium sordellii lethal and haemorrhagic toxin and Clostridium novyi α-toxin (Table 1). These toxins are exotoxins which induce morphological changes of the cultured target cells based on the redistribution of the microfilament system. The cytotoxic activity on cultured cell lines led to their designation as cytotoxins. Despite their comparable in vitro effects, the cytotoxins — as major pathogenicity factors — are involved in different diseases and clinical outcomes. Clostridium difficile toxins A and B are of major clinical importance because both toxins are the causative agents in about 20% of antibiotic-associated diarrhoea and in almost all cases of pseudomembranous colitis (Kelly et al. 1994; Kelly and Lamont 1998; Bartlett 1994).

Keywords

Nucleotide Sugar Lethal Toxin ToxinA Alpha Substrate Recognition Site Glucosyltransferase Activity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • I. Just
    • 1
  • F. Hofmann
    • 1
  • K. Aktories
    • 1
  1. 1.Institut für Pharmakologie und ToxikologieUniversität FreiburgFreiburgGermany

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