Exploring the venom of Ectatomma brunneum Smith (Hymenoptera: Formicidae)

Ant venom has several functions, including predation, communication, defense against predators, and action against pathogens. There is a scarcity of data about ant venom components that could provide support for understanding the mechanisms of action. The objective here was to identify the amino acids and proteins in the venom of the predatory ant Ectatomma brunneum and to evaluate its antimicrobial activity. The amino acids were analyzed by liquid chromatography, with diode array detection, and were identified using amino acid standards. The two-dimensional (2D) gel electrophoresis fractionation approach was used to identify the proteins, together with MALDI-TOF/TOF mass spectrometry and protein databases. The antimicrobial activity of the venom was evaluated using the minimum inhibitory and minimum microbiocidal concentrations. The venom of E. brunneum contained free amino acids, with a high amount of alanine. The 2D gel analysis showed 104 spots, of which 21 were identified and classified according to biological function, as follows: venom proteins, nontoxic reservoir protection, cellular maintenance proteins, and proteins with unknown function. The venom showed antimicrobial activity, inhibiting the growth of all the bacteria and fungi tested. The results provide new insights into ant venom components and antimicrobial activity.