Study of the δ-endotoxins produced by three recently isolated strains of<i>Bacillus thuringiensis</i>

Abstract

Three different strains of Bacillus thuringiensis, subsp. toumanoffi, sotto and kurstaki, producing parasporal inclusion crystals, have recently been isolated in Tunisia. The δ-endotoxins produced by the different strains gave distinct patterns on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Polymerase chain reaction screening of these three strains, using oligonucleotides specific for the genes cryIA, cryIII and cryIV, did not generate amplified fragment profiles characteristic of these genes. For each of the strains, the presence of one or more δ-endotoxin coding genes having partial sequence similarities to one or more genes of these three groups was found.