<prompt> Toxin acting on cGMP-Heat stable E. coli toxinHeat labile E. coli toxinCholera toxinShiga toxin  <response>: Ans. is a i.e., Heat stable E. coli toxin . Cholera toxin CT and labile toxin of E.coli LT act by activating cAMP. . Stable toxin of E.coli acts by activating cGMP. Remember . Though the mechanism of labile toxin of E.coli LT and cholera toxin CT is same, cholera toxin is about a hundred times more potent than LT. 