Escherichia coli enterotoxin: stimulation of adenylate cyclase in broken-cell preparations.
The enterotoxin from cell-free filtrates of the enteropathogenic Escherichia coli strain P-263 was found to stimulate adenylate cyclase activity in broken-cell preparations from myocardial tissue. Particulate and detergent-solubilized fractions from cat heart were incubated with enterotoxin and assayed for adenylate cyclase activity. Adenylate cyclase activity was stimulated by enterotoxin; the extent of stimulation was proportional to the concentration of enterotoxin. The data demonstrate that stimulation of enterotoxin-sensitive adenylate cyclase in this system provides a sensitive in vitro assay, either as an accurate measure of enterotoxin concentration or as an assay for antitoxic titers in sera. A parallel comparison showed that stimulation of fluid production in rabbit intestinal loops by enterotoxin was less sensitive.
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D000992:Antitoxins; D002415:Cats; D000242:Cyclic AMP / Q000378:metabolism; D003902:Detergents; D004768:Enterotoxins / Q000302:isolation & purification / Q000494:pharmacology*; D004926:Escherichia coli / Q000276:immunology*; D006041:Goats / Q000276:immunology; D006358:Hot Temperature; D007422:Intestines / Q000276:immunology; D009206:Myocardium / Q000201:enzymology*; D009500:Neutralization Tests; D010718:Phosphatidylserines; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D011817:Rabbits / Q000276:immunology; D011865:Radioisotope Dilution Technique; D013806:Theophylline; D013974:Thyroxine; D013997:Time Factors; D014316:Tritium; D014688:Venoms
D000992:Antitoxins; D003902:Detergents; D004768:Enterotoxins; D010718:Phosphatidylserines; D014688:Venoms; D014316:Tritium; D013806:Theophylline; D000242:Cyclic AMP; D010727:Phosphoric Diester Hydrolases; D000262:Adenylyl Cyclases; D013974:Thyroxine