MOLECULAR MODELING OF DERMASEPTINE SP2 EXTRACTED FROM Agalychnis spurrelli

Abstract

In this research, we present a computational study of Dermaseptine SP2 (DRS-SP2) extracted from the skin of the frog Agalychnis spurrelli. Experimental assays allowed extracting, purifying and obtaining the amino acid sequence of this peptide. Furthermore, they have demonstrated its antimicrobial properties against Escherichia coli, Staphylococcus aureus and Candida albicans. With the sequence, a computational study of the structure was carried out, obtaining its physical-chemical properties, its secondary structure and its similarity with other known peptides. Also, a molecular docking study of this peptide was performed against cell membrane and several enzymes known to kill these microorganisms. Results showed that DRS-SP2 is an α-helical cationic peptide with an isoelectric point of 10.68 and a positive charge +3 at physiological pH. It was determined that its structure is different to all dermaseptines found in databases reaching a maximum identity of 80 %. Molecular docking studies suggest the mechanism of action of this peptide is not given by the inhibition of a vital enzymatic pathway, but by destruction of the microorganism by cell lysis.