The cloned insect specific δ-endo toxin gene from BTT was altered by site directed mutagenesis at its 5`-end and adapted for general cloning and expression purpose with a linker including a start codon and new restriction sites. The altered toxin gene was inserted into a modified binary vector plasmid pBinAR. Transfer of this recombinant plasmid was accomplished with the binary vector system via plants leaf disk infection. Toxin-containing protein from the transgenic plants was identified by Westhern blot analysis. The leaf extracts from the plants had insecticidal activity on larvae of the Colorado potato beetle.