Characterization of a novel Bacillus thuringiensis toxin active against Aedes aegypti larvae

Some Bacillus thuringiensis (Bt) strains produce dipteran-active toxins and can control larval mosquitoes. We identified a novel mosquitocidal toxin named Xpp81Aa1 with the thioredoxin domain from Bt strain HSY204. This toxin has very little sequence similarity to the three-domain Cry toxin and Cyt toxins and has significant toxicity to Aedes aegypti larvae. A safety assessment indicated that the Xpp81Aa1 toxin has no cytocidal activity against red blood cells and did not induce allergic reactions. The Xpp81Aa1 toxin exhibited a synergistic effect in combination with Cry2Aa and Cry4Aa protein toxins. Thus, the Xpp81Aa1 toxin could be a good candidate for mosquito control applications to reduce the mosquito-borne disease.

Automated summary

The novel mosquitocidal toxin Xpp81Aa1, identified from Bacillus thuringiensis strain HSY204, has significant toxicity to Aedes aegypti larvae, shows little similarity to traditional Cry and Cyt toxins, and exhibits a synergistic effect when combined with Cry2Aa and Cry4Aa protein toxins. Safety assessment revealed no cytocidal activity or allergic reactions, making Xpp81Aa1 a promising candidate for mosquito control applications to reduce mosquito-borne diseases.