[Change in the permeability of liposome phospholipid membranes under the effect of Bacillus thuringiensis delta-endotoxins].

We studied release of the fluorescent calcein marker from egg-lecithin liposomes under action of intact delta-endotoxin from Bacillus thuringiensis var. israilensis, and hydrolysed preparation of delta-endotoxin from Bacillus thuringiensis var. kurstaki together with the motional parameters of 5- and 12-doxyl stearic radical probes in the liposomal membrane. The yield of the non-penetrating fluorescent marker was shown to be a sensitive indicator of the disturbance of the membrane barrier function.