Isolation of a hemolysin from a spore - crystal mixture of Bacillus thuringiensis israelensis (serotype H-14)

Isolation of a hemolysin from a spore - crystal mixture of Bacillus thuringiensis israelensis (serotype H-14). Toxicon 26, 733 – 746, 1988. — A hemolytic toxin from Bacillus thuringiensis israelensis was obtained by alkaline extraction and fast protein liquid chromatography (chromatofocusing followed by gel filtration). The toxin displayed a pl of 4.6 – 4.8 and an M r of 26,000. Amino acid analysis demonstrated large amounts of serine, glycine and glutamic acid. The toxin was strongly lytic for rabbit, human and non-human primate erythrocytes, and was weakly lytic toward equine, feline, canine, bovine, amphibian and reptilian erythrocytes. It was weakly entomocidal as indicated by a lethal potency ( LC 50 ) of 25 μg/ml for second instar larvae of Anopheles stephansi . Direct micro-ELISA indicated that the toxin lacked antigenic identity with numerous eukaryotic and prokaryotic toxins and venoms.