Domain-guided engineering of a thermoresistant Vip3A toxin for enhanced functional robustness
Issued Date
2026-12-01
Resource Type
eISSN
20452322
Scopus ID
2-s2.0-105036456709
Pubmed ID
42014424
Journal Title
Scientific Reports
Volume
16
Issue
1
Rights Holder(s)
SCOPUS
Bibliographic Citation
Scientific Reports Vol.16 No.1 (2026)
Suggested Citation
Kunlawatwimon T., Bourdeaux F., Boonserm P., Soonsanga S., Luka J., Promdonkoy B., Schwaneberg U. Domain-guided engineering of a thermoresistant Vip3A toxin for enhanced functional robustness. Scientific Reports Vol.16 No.1 (2026). doi:10.1038/s41598-026-47865-0 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/116511
Title
Domain-guided engineering of a thermoresistant Vip3A toxin for enhanced functional robustness
Corresponding Author(s)
Other Contributor(s)
Abstract
Vip3A toxins from Bacillus thuringiensis are effective insecticidal agents for lepidopteran pest control, but their application is limited by poor thermal stability and loss of activity during storage. In this study, we engineered a thermoresistant Vip3Aa64 variant using a combined rational design and directed-evolution approach. Structural analysis and thermal profiling identified domains IV and V as the primary determinants of instability. Rational design targeting domain V yielded stabilizing substitutions that enhanced interdomain interactions, while error-prone mutagenesis of domain IV coupled with high-throughput nanoscale differential scanning fluorimetry screening identified additional mutations conferring increased thermal resistance. Combining the most effective substitutions and removing a mutation that reduced toxicity produced the variant Vip3A-TR6 (I408E/M755K/N633V/G580E), which exhibited a 5.1 °C increase in melting temperature without compromising insecticidal activity against Spodoptera exigua. Vip3A-TR6 displayed enhanced resistance to heat-induced aggregation and retained bioactivity after prolonged storage at 25 °C and 37 °C. Importantly, the variant was efficiently produced and secreted by B. thuringiensis. These results demonstrate a robust strategy for improving the robustness of Vip3A toxins and support the development of more durable Vip3A-based biopesticides.