Determination of mosquito Larvicidal potential of Bacillus thuringiensis Cry11Ba fusion protein through molecular docking

Mosquitoes spread deadly infections around the world. Since decades Bacillus thuringiensis (Bt) δ-endotoxins have been used successfully as a biopesticide for controlling mosquito larvae. However, over a few years, mosquito larvae have evolved tolerance against Bt δ-endotoxins, rendering them ineffective for mosquito control. Such a problem entails the development of improved toxins with enhanced toxicity, affinity towards a wide range of mosquito receptors and ability to overcome or delay the resistance buildup. In this study, using in silico tools, we aimed to design a fusion protein by fusing active region of Bt subsp. jegathesan Cry11Ba protein with Aedes aegypti TMOF (trypsin modulating oostatic factor). Using computational study, the fusion protein was validated and its mosquitocidal potential was determined through molecular docking against cadherin and aminopeptidase N midgut receptors of Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Molecular docking revealed that from Cry11Ba-TMOF fusion protein, domain II amino acids of Cry11Ba protein showed hydrogen bond interactions with cadherin and aminopeptidase N receptors of the targeted mosquitoes. These results conclude that Cry11Ba-TMOF fusion protein has a strong affinity for the receptors of Ae.aegypti, An.gambiae and Cx.quinquefasciatus. Thus the designed fusion protein can be used as a potent mosquitocidal agent for the control of targeted mosquitoes.