Identification of a Catabolite-Responsive Element Necessary for Regulation of the cry4A Gene of Bacillus thuringiensis subsp. israelensis▿ †

摘要

Bacillus thuringiensis subsp. israelensis produces a potent mosquitocidal protein, Cry4A. We have identified a 15-bp catabolite responsive element (cre), overlapping the −35 element of the cry4A promoter. Changing a guanine to adenine at position −49 in the promoter abolished glucose catabolite repression of cry4A and enhanced promoter activity two- to threefold. This cis regulatory element is essential for controlled toxin synthesis, vital to evolutionary success of B. thuringiensis subsp. israelensis.