Investigation of 'E. coli' Enterotoxins
Annual rept. Aug 1973-Jun 1974
WYETH LABS INC PHILADELPHIA PA
Pagination or Media Count:
The report summarizes research performed in the areas of toxin production, assay and purification. One of the major aspects of the work has been the demonstration that Escherichia coli enterotoxins, like cholera toxin, cause vascular permeability changes in rabbit skin. This observation has permitted the application of the rabbit skin test developed for cholera toxin to the measurement of E. coli heat-labile enterotoxin. By using this assay, it has been possible to investigate a variety of growth conditions and to select from these a set of conditions a modified syncase medium supplemented with yeast extract 24 h shaker cultures 37C which have been used routinely to produce enterotoxin for purification studies. At the same time, the availability of the assay has permitted the screening of a number of drug-resistant variants for increased toxin production.