Diversity of peptide toxins from stinging ant venoms

Abstract

Ants (Hymenoptera: Formicidae) represent a taxonomically diverse group of arthropods comprising nearly 13,000 extant species. Sixteen ant subfamilies have individuals that possess a stinger and use their venom for purposes such as a defence against predators, competitors and microbial pathogens, for predation, as well as for social communication. They exhibit a range of activities including antimicrobial, haemolytic, cytolytic, paralytic, insecticidal and pain-producing pharmacologies. While ant venoms are known to be rich in alkaloids and hydrocarbons, ant venoms rich in peptides are becoming more common, yet remain understudied. Recent advances in mass spectrometry techniques have begun to reveal the true complexity of ant venom peptide composition. In the few venoms explored thus far, most peptide toxins appear to occur as small polycationic linear toxins, with antibacterial properties and insecticidal activity. Unlike other venomous animals, a number of ant venoms also contain a range of homodimeric and heterodimeric peptides with one or two interchain disulfide bonds possessing pore-forming, allergenic and paralytic actions. However, ant venoms seem to have only a small number of monomeric disulfide-linked peptides. The present review details the structure and pharmacology of known ant venom peptide toxins and their potential as a source of novel bioinsecticides and therapeutic agents.

The complexity and structural diversity of ant venom peptidomes is revealed by mass spectrometry profiling

“…This finding is consistent with previous reports of large peptides described and sequenced from formicoid ant venoms such as ectatomins, myrmexins and pilosulins . It should be noted that the higher peptide masses are associated with dimeric forms of peptides, often associating two linear chains linked by interchain disulfide bonds . In the range of species studied, the proportion of large peptides ([M+H] + ions > m/z 4000) found in ant venoms from the poneroid clade was significantly lower than in the formicoid clade (Mann–Whitney U = 280, n 1 = n 2 = 41, P <0.001).…”

Structure-Activity Relationships of Insect Defensins

“…This includes for example antimicrobial peptides (AMP) that represent an important part of the organism's defense machinery or peptide toxins as part of venom cocktails (Brogden et al, 2003; Favreau et al, 2006; Aili et al, 2014). AMPs are a diverse class of naturally occurring compounds that have been identified in a variety of organisms, from invertebrates to vertebrates including humans (Shafee et al, 2017).…”

Intraspecific variations in the venom peptidome of the ant Odontomachus haematodus (Formicidae: Ponerinae) from French Guiana

“…As they have been little studied, ant venom peptides represent a potentially promising source of bioactive molecules with novel scaffolds and original pharmacological activities. Previous studies (Aili et al 2014;Touchard et al 2014;Touchard et al 2015) have demonstrated that the venoms of stinging ants are mostly comprised of small peptides, similarly to spider, scorpion and cone snail venoms. A limited number of peptidic toxins from several ant subfamilies such as the Ponerinae (Cologna et al 2013;Johnson et al 2010;Orivel et al 2001), Paraponerinae (Piek et al 1991), Ectatomminae (Arseniev et al 1994;Pluzhnikov et al 2000), Myrmicinae (Rifflet et al 2012), Myrmeciinae (Inagaki et al 2004;Inagaki et al 2008) and Pseudomyrmecinae (Pan and Hink 2000) have been characterized.…”