A novel dodecadepsipeptide, cereulide, isolated from Bacillus cereus causes vacuole formation in HEp-2 cells.

A HEp-2 cell-vacuolation factor was extracted and purified from the culture supernatant of a Bacillus cereus strain which caused emetic-syndrome food poisoning. The final preparation was chemically pure, and the toxin was named as cereulide. Mass spectrometry, NMR studies and chemical degradation revealed that the cereulide is a cyclic dodecadepsipeptide, (D-O-Leu-D-Ala-L-O-Val-L-Val)3, which is closely related to the potassium ionophore, valinomycin.