The neonicotinoid imidacloprid impairs the predatory performance and functional response of the jumping spider Helpis minitabunda (Araneae, Salticidae)

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  The neonicotinoid imidacloprid impairs the predatory performance and functional response of the jumping spider Helpis minitabunda (Araneae, Salticidae) Abstract The neonicotinoid imidacloprid can cause lethal and sublethal effects in non-target organisms, including impaired behavior, reduced fertility, disrupted locomotion, and reduced predatory performance in arthropods. Spiders are among the most abundant arthropod predators in terrestrial ecosystems, including agricultural ecosystems, yet the effects of neonicotinoids on the predatory function of jumping spiders remain poorly understood. The functional response of a predator describes how predation rates change with prey density and is key to understanding predator–prey dynamics. We tested whether acute exposure to a commercial formulation of imidacloprid at field-recommended concentrations alters the functional response of the Aussie bronze jumping spider, Helpis minitabunda (L. Koch, 1880). We compared the predation of treat...

Proteolytic stabilization of a spider venom peptide results in an orally active bioinsecticide

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Proteolytic stabilization of a spider venom peptide results in an orally active bioinsecticide

Abstract

BACKGROUND

The toxin peptide U1-AGTX-Ta1b from the Hobo spider, Eratigena agrestis (Walckenaer, 1802), was studied to determine its potential to serve as a bioinsecticide.

RESULTS

U1-AGTX-Ta1b has insecticidal potencies similar to commercial insecticides when injected directly into insect hemolymph but lacks activity when ingested by lepidopterans due to trypsin-like gut proteases. Alanine scanning identified an arginine and lysine rich patch on the peptide's surface that is critical for bioactivity. Targeted stability studies on these basic residues identified a single site, R9, to be the rate limiting site in U1-AGTX-Ta1b proteolysis. Mutation of position R9 to glutamine was sufficient to stabilize the peptide and render the toxin orally active with the additional benefit of enhanced temperature stability. Further refinement of the peptide to remove an O-linked glycosylation site and prevent exoprotease activity during expression in yeast led to a final peptide sequence suitable for commercialization as a bioinsecticide. This peptide displayed activity comparable to commercial insecticides in a range of crop/pest combinations.

CONCLUSION

A novel, peptide-based bioinsecticide derived from spider venom was developed to be stable and active by ingestion by lepidopteran pests. The peptide, U1-AGTX-Ta1b-QA, can replace or reduce the use of chemical insecticides and has been approved by the United States Environmental Protection Agency. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Davis, B. R., Haase, A. M., Tourtois, J. S., Hulbert, D. L., Cornell, R. E., DeVree, B. T., Flohrschutz, C. J., Bell, L. M., Peck, D. C., Nguyen, T. T., Bao, L., Kennedy, R. M., & Schneider, K. D. Proteolytic stabilization of a spider venom peptide results in an orally active bioinsecticide. Pest Management Science. https://doi.org/10.1002/ps.8980