title: Cellular release of heat-labile enterotoxin of Escherichia coli by bacteriophage induction.
abstract: Treatment of some enterotoxigenic Escherichia coli strains with the antibiotic mitomycin C resulted in lysis of the bacteria. Heat-labile enterotoxin (LT) activity of culture filtrates, determined by means of the Y-1 adrenal cell assay, increased dramatically as lysis of the culture proceeded. Further studies with E. coli strains 263 and B21-4 revealed that lysis is due to mitomycin C induction of vetetative development of a temperature bacteriophage. These findings suggest that the elevated levels of LT detected after mitomycin C treatment reflect the lytic release of cell-bound LT rather than the induction by mitomycin C of de novo toxin biosynthesis. Comparable increases in LT activity also resulted from thermal induction of a phage P1Cm lysogen of strain 263 or from sonic disruption of enterotoxigenic strains.
mesh_terms: D001427:Bacterial Toxins / Q000378:metabolism*; D001433:Bacteriolysis / Q000187:drug effects; D003090:Coliphages / Q000254:growth & development*; D004768:Enterotoxins / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism; D006358:Hot Temperature; D008242:Lysogeny / Q000187:drug effects; D008937:Mitomycins / Q000494:pharmacology*; D013010:Sonication; D014779:Virus Replication / Q000187:drug effects
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D008937:Mitomycins