Nonkhwao Siriporn, Plettner Erika, Daduang Sakda
Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand.
Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
Molecules. 2024 Feb 27;29(5):1033. doi: 10.3390/molecules29051033.
Sol g 2 is the major protein in fire ant venom. It shares the highest sequence identity with Sol i 2 () and shares high structural homology with LmaPBP (pheromone-binding protein (PBP) from the cockroach ). We examined the specific Sol g 2 protein ligands from fire ant venom. The results revealed that the protein naturally formed complexes with hydrocarbons, including decane, undecane, dodecane, and tridecane, in aqueous venom solutions. Decane showed the highest affinity binding (K) with the recombinant Sol g 2.1 protein (rSol g 2.1). Surprisingly, the mixture of alkanes exhibited a higher binding affinity with the rSol g 2.1 protein compared to a single one, which is related to molecular docking simulations, revealing allosteric binding sites in the Sol g 2.1 protein model. In the trail-following bioassay, we observed that a mixture of the protein sol g 2.1 and hydrocarbons elicited worker ants to follow trails for a longer time and distance compared to a mixture containing only hydrocarbons. This suggests that Sol g 2.1 protein may delay the evaporation of the hydrocarbons. Interestingly, the piperidine alkaloids extracted have the highest attraction to the ants. Therefore, the mixture of hydrocarbons and piperidines had a synergistic effect on the trail-following of ants when both were added to the protein.
Sol g 2是火蚁毒液中的主要蛋白质。它与Sol i 2（）具有最高的序列同一性，并且与LmaPBP（蟑螂的信息素结合蛋白（PBP））具有高度的结构同源性。我们研究了火蚁毒液中特定的Sol g 2蛋白质配体。结果表明，在水性毒液溶液中，该蛋白质与包括癸烷、十一烷、十二烷和十三烷在内的碳氢化合物自然形成复合物。癸烷与重组Sol g 2.1蛋白（rSol g 2.1）表现出最高的亲和力结合（K）。令人惊讶的是，与单一烷烃相比，烷烃混合物与rSol g 2.1蛋白表现出更高的结合亲和力，这与分子对接模拟有关，揭示了Sol g 2.1蛋白模型中的变构结合位点。在追踪生物测定中，我们观察到，与仅含碳氢化合物的混合物相比，蛋白质sol g 2.1和碳氢化合物的混合物能使工蚁追踪路径的时间更长、距离更远。这表明Sol g 2.1蛋白可能会延缓碳氢化合物的蒸发。有趣的是，提取的哌啶生物碱对蚂蚁具有最高的吸引力。因此，当碳氢化合物和哌啶都添加到蛋白质中时，它们对蚂蚁追踪路径具有协同作用。
