Title: Asporogenous Bacillus thuringiensis Mutant Producing High Yields of δ-Endotoxin
Abstract: An asporogenous Bacillus thuringiensis subsp. kurstaki strain IK mutant, strain 290-1, which produced high yields of δ-endotoxin, was obtained by ethyl methane sulfonate treatment of a spore suspension. The mutant strain produced about the same amount of δ-endotoxin as that produced by the parent strain, but 10 10 to 10 11 cells did not form any detectable dormant spores.