Promotes colloidosmotic lysis by binding to the midgut epithelial cells of mosquitos. Active against Aedes aegypti and Culex quinquefasciatus larvae. The crystal protein is produced during sporulation and is accumulated both as an inclusion and as part of the spore coat. Has low mosquitocidal activity probably due to rapid proteolysis to inactive 56 kDa and 43 kDa proteins. Toxic segment of the protein is located in the N-terminus. Belongs to the delta endotoxin family.