Expression of Chromosomally InsertedBacillus thuringiensis israelensisToxin Genes inBacillus sphaericus

Bacillus thuringiensis israelensisδ-endotoxin genes were inserted into transposon Tn917in plasmid pTV51Ts and cloned into the chromosome ofBacillus sphaericus2362. Many of the transformants reacted with antibody to the 135-, 128-, 65-, and 28-kDaB.t.israelensistoxin proteins and were approximately 10 times more toxic toA. aegyptilarvae than the untransformed host. Some of the transformants differed physiologically and morphologically from the wild-typeB. sphaericus.The toxicity of the transformed phenotype was maintained through many transfers in the absence of selective pressure.