The cellular fatty acid composition of Bacillus thuringiensis var. israelensis (B.t.i.) from 5 commercial brands (Vectobac, Acrobe, Skeetal, Bactimos and Teknar), as well as of the current International Standard for B.t.i. (IPS 82), was determined using a Hewlett-Packard Microbial Identification System. The original strain of B.t.i., B.t. var. kurstaki, B.t. var. thuringiensis, B.t. var. morrisoni and Bacillus sphaericus strain 2362 were used as outgroups. Acrobe, Bactimos, Teknar, Vectobac and IPS 82 consisted of the same strain. Skeetal represented a different strain than the other commercially produced B.t.i. Our results indicate that cellular fatty acid analysis can be used to distinguish among the forms of B.t.i. produced by various manufacturers.
