Análise de peptídeos antimicrobianos na formiga Odontomachus chelifer (Latreille, 1802) (Formicidae: Ponerinae) a partir de dados transcriptômicos

Abstract

Hymenopteran venoms contain a complex mixture of potent bioactive substances, which have potential biotechnological applications. Ant venoms are composed of formic acid, alkaloids, biogenic amines, enzymes, hydrocarbons, peptides, polypeptides and proteins. These components have antifungal, antiparasitic, antimicrobial, antiviral, phospholipase, cytolytic and neurotoxic properties. The venom of the species Odontomachus chelifer, a carnivorous ant, was investigated in this study in an novel way. O. chelifer is a carnivorous, nocturnal, large ant with an anatomical body characteristic of its species, featuring a robust mandible. Its sting causes acute and intense pain, prolonged itching and burning. In this study, we investigated, using in silico techniques, the peptides that make up a supposed antimicrobial arsenal from the venom gland of the neotropical ant Odontomachus chelifer. Based on transcripts from the body and venom gland of this insect, it was possible to determine the secretome of the gland, which contained around 1,022 peptides with supposed signaling peptides. Most of these peptides (75.5%) were unknown and did not correspond to any reference database, motivating us to extract functional information using techniques based on automated data analysis. We used several complementary methodologies such as transcriptomic data to investigate the existence of antimicrobial peptides (AMPs) in the venom gland of O. chelifer, finding 112 non-redundant candidates. The PAMs were submitted to online bioinformatics tools (AI4AMP, AMPlify, AMP Scanner v2, amPEPpy, Macrel v.1.2.0, UNIPROT version 2022_05, CPAMR3, CAMPSign, Blastp) and the NCBI database. The candidate AMPs were predicted to be more globular and hemolytic than the remaining peptides in the secretome. There is evidence of transcription for 97% of the candidate AMPs in the same genus of ants, with one of them also verified as translated, thus supporting our findings. Most of these sequences with antimicrobial potential (94.8%) corresponded to transcripts from the ant's body, indicating their role not only as venom toxins.