Ants
from the genus Dinoponera are believed to be the world’s largest living ants
with a body length of 3cm. Their occurrence is restricted to tropical areas
of South America. Despite the noxious effects inflicted by its envenomation,
the information about the biological properties and composition of their venom
is still limited. In this work, we study the venom of the giant Dinoponera quadriceps ant collected in 4
different regions of Brazil. By using combinatorial mass spectrometric approaches,
we aim at: (i) characterizing the venom composition of these ants; (ii)
establishing a comparative analysis of the venom from the 4 different regions. The ants were captured in the surroundings of
Contendas, Manoel Vitorino, Caetite and Feira de Santana (Brazil). Venom
was extracted by mechanical stimulation and then dried. An aliquot of each
sample was analyzed by MALDI-TOF/TOF and nanoLC-ESI-Q-TOF. The combinatorial
mass spectrometry analyses demonstrate that ant venom is a copious source of
new compounds. Several new peptides were identified and selected for “de novo sequencing”. Since most of our
new peptides showed similarities with antimicrobial peptides (AMPs),
antimicrobial assays were performed with the purpose of evaluating their
activity. The biological assays were carried out on a broad spectrum of
microorganisms, including Gram-positive and Gram-negative bacteria, yeasts and
fungi. In regard to the comparative study, we observed considerable
differences in the venom composition which could be linked to an adaption to
the environment. Concerning the biological assays, the peptides called Dq-3162
and Da-3177 showed a wide-ranging antimicrobial activity. In an increasing
antibiotic resistance era, the description and characterization of new AMPs
with a broad spectrum of activity and different scaffolds may aid scientists to
design new therapeutic agents and understand the mechanisms of those peptides
to interact with microbial membranes. The results obtained pinpoint the
biotechnological potential of ant´s venom.