Production of Shigella dysenteriae type 1-like cytotoxin by Escherichia coli.
Strains of Escherichia coli previously implicated or proven to be causes of diarrhea were examined for production of a toxin similar to that of Shigella dysenteriae type 1 (Shiga). Organisms grown in an iron-depleted broth were lysed by pressure disruption followed by ultracentrifugation. Saline-dialyzed extracts were tested for cytotoxic effects on HeLa cells that were neutralizable with antiserum to Shiga toxin. Among the 13 E. coli strains so analyzed, 11 made a Shiga-like cytotoxin in levels ranging from trace (two avirulent isolates) to amounts equivalent to S. dysenteriae type 1 (two noninvasive strains that did not make E. coli heat-labile or -stable enterotoxins but were isolated from infants with diarrhea). As with extracts of Shiga toxin, lysates of these E. coli strains that produced high levels of Shiga-like toxin were enterotoxic for rabbits, paralytic and lethal for mice, and inhibited protein synthesis in HeLa cells. Thus, these data suggest that Shiga-like toxin may be another heretofore undiscovered factor in the pathogenesis of diarrhea caused by some E. coli strains.
D000818:Animals; D001427:Bacterial Toxins / Q000096:biosynthesis*; D003603:Cytotoxins / Q000096:biosynthesis*; D004926:Escherichia coli / Q000378:metabolism* / Q000472:pathogenicity; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D014176:Protein Biosynthesis; D011817:Rabbits; D022603:Shiga Toxins
D001427:Bacterial Toxins; D003603:Cytotoxins; D022603:Shiga Toxins