Análisis bioinformático de péptidos con actividad antimicrobiana

Abstract

This project was made with the purpose of studying the great antimicrobial potential of different proteins like response to developing of resistance of pathogenic microorganisms to conventional antimicrobial compounds. To reach this goal, a total of 126 peptides was collected and analyzed from the PDB and UniProt. The analyzed proteins belong to various species and have been into 12 groups such as cecropins, magainins, bombinins, dermaseptins, cathelicidins, brevinins, esculentins, ranalexins, defensins, drosocins, PR- 39 and gaeugerins. Multiple sequence alignment showed that peptides have highly conserved regions, which generate folding patterns responsible for their activity. When ordering the 126 antimicrobial peptides into 4 groups according to their secondary structure, a high conservation was identified between peptides of different classes and origin, this explains the similarities that these peptides present when interacting with the phospholipid bilayer of microorganisms, proving that the most used mechanisms of action is the “barrel stave” mode, the amphipathicity of these molecules allows the hydrophobic end to interact with the lipid core of the membrane, while the hydrophilic end is directed inwards, producing an aqueous pore. Finally, a phylogenetic tree was constructed by the maximum likelihood method for each class of antimicrobial peptides. From this analysis it was concluded that although the analyzed sequences belong to different species, these are related because they maintain the same evolutionary line and mechanism of action. In summary, this study offers a starting pint for the identification of peptides of interest through the use of open databases, which potentially antimicrobial activity.