The insecticidal character of the three-domain Cry -endotoxins produced by Bacillus thuringiensis during sporulation is believed to be caused by their capability to generate lytic pores in the target larval midgut cell membranes. This review describes toxic mechanisms with emphasis on the structural basis of pore formation by two closely related dipteran-specific toxins, Cry4Aa and Cry4Ba, whic...

Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, ...