Deletion Mutants of the Gene Encoding δ-Endotoxin Specific to Scarabaeid Beetles: Minimum Region of the Gene Required to Express the Activity

Various deletion genes for the δb-endotoxin protein of Bacillus thuringiensis strain Buibui were made. The truncated proteins were produced in E. coli, and their larvicidal activity against the cupreous chafer was checked. The fifth block of the five blocks described as “conserved” was shown to be necessary for the activity.