An experimental compound is discovered that prevents the activation of adenyl cyclase and the resulting increase in cyclic AMP. The toxic effects of which of the following bacteria might be prevented with the use of this experimental compound?

The toxin of V. cholerae and LT enterotoxin from Escherichia coli are similar. The B subunits of the toxins bind to ganglioside GM1 receptors on the host cell. The A subunits catalyze transfer of the ADP-ribose moiety of ADP to a regulatory protein known as Gs. This activated Gs stimulates adenyl cyclase. Cyclic AMP is increased as is fluid and electrolyte release from the crypt cells into the lumen of the bowel. Watery, profuse diarrhea ensues.