Vector venom: venomics of Aedes albopictus reveals a large enzyme repertoire and novel cecropins with activity against E. coli.

Mosquitoes are vectors of deadly diseases and pose a global health threat. Particularly, the Asian tiger mosquito Aedes albopictus can transmit several pathogens, and is expanding into temperate regions. During blood feeding, mosquitoes inject chemically complex saliva, here referred to as venom, which modulates hemostasis, inflammation, immune response and pathogen transmission. In-depth knowledge of mosquito venom is crucial for understanding disease biology and enabling biodiscovery. We present a venomics study of Ae. albopictus and identify 119 distinct proteins validated by mass spectrometry and transcriptomics. The venom is rich in enzymes (e.g., hydrolases and Apyrases) and non-enzymatic components (e.g., odorant binding proteins and protease inhibitors). Additionally, we identified six novel cecropin family antimicrobial peptides. Structural analyses indicate an amphipathic N-terminus, hinge region, and hydrophobic C-terminus consistent with type II channel formation. Functional assays revealed that these cecropins exert potent effects on E. coli while leaving mammalian epithelial cells and erythrocytes unaffected. Overall, our study reveals that mosquito venom is a source of diverse biomacromolecules, deepening our understanding of its physiology, vector biology, and biochemical ecology. This opens paths for new mosquito-control strategies and drug discovery.