TY - JOUR PY - 2014// TI - Venom toxicity and composition in three Pseudomyrmex ant species having different nesting modes JO - Toxicon: Journal of the International Society on Toxinology A1 - Touchard, Axel A1 - Labrière, Nicolas A1 - Roux, Olivier A1 - Petitclerc, Frédéric A1 - Orivel, Jérôme A1 - Escoubas, Pierre A1 - Koh, Jennifer M. S. A1 - Nicholson, Graham M. A1 - Dejean, Alain SP - 67 EP - 76 VL - 88 IS - N2 - We aimed to determine whether the nesting habits of ants have influenced their venom toxicity and composition. We focused on the genus Pseudomyrmex (Pseudomyrmecinae) comprising terrestrial and arboreal species, and, among the latter, plant-ants that are obligate inhabitants of myrmecophytes (i.e., plants sheltering ants in hollow structures). Contrary to our hypothesis, the venom of the ground-dwelling species, P. termitarius, was as efficacious in paralyzing prey as the venoms of the arboreal and the plant-ant species, P. penetrator and P. gracilis. The lethal potency of P. termitarius venom was equipotent with that of P. gracilis whereas the venom of P. penetrator was less potent. The MALDI-TOF MS analysis of each HPLC fraction of the venoms showed that P. termitarius venom is composed of 87 linear peptides, while both P. gracilis and P. penetrator venoms (23 and 26 peptides, respectively) possess peptides with disulfide bonds. Furthermore, P. penetrator venom contains three hetero- and homodimeric peptides consisting of two short peptidic chains linked together by two interchain disulfide bonds. The large number of peptides in P. termitarius venom is likely related to the large diversity of potential prey plus the antibacterial peptides required for nesting in the ground. Whereas predation involves only the prey and predator, P. penetrator venom has evolved in an environment where trees, defoliating insects, browsing mammals and ants live in equilibrium, likely explaining the diversity of the peptide structures.

Language: en

LA - en SN - 0041-0101 UR - http://dx.doi.org/10.1016/j.toxicon.2014.05.022 ID - ref1 ER -