Resumen:
Defensive peptides from amphibian skin secretions have generated great interest in the
world for their antibacterial, antifungal, antiprotozoal, wound healing, antioxidant, and
even anticancer capabilities. Between them, antimicrobial peptides (AMPs) are considered
as a potential therapeutic alternative against infections caused by microorganisms resistant
to conventional antibiotics. In Phyllomedusidae family, new AMPs have been described,
with strong antimicrobial activity with low or no hemolytic activity, considering them
potential for clinical development. In Ecuador, there are species belonging to this family,
with biomedical potential that are in danger of extinction and unexplored as a source of
new MPAs, such as Callimedusa ecuatoriana. This study reports for the first time analysis
of the antimicrobial potential of C. ecuatoriana cutaneous secretion through fractionation
by high performance liquid chromatography (HPLC), antimicrobial assays and matrix assisted mass spectrometry (MALDI-TOF MS). In addition, the primary structure of the first
peptide (Ikiam2599) from C. ecuatoriana skin obtained by molecular cloning is reported.
From the analysis of its precursor sequence against described peptides, it was identified
that Ikiam2599 peptide belongs to the recently described Picturin family. The synthetic
peptide Ikiam2599 lacks hemolytic and antibacterial activity against Escherichia coli and
Staphylococus aureus: additionally, it lack antifungal activity. This study demonstrates the
biomedical potential of the C. ecuatoriana cutaneous secretion, also showing the potential
of unexplored biological and molecular diversity in endemic species of Ecuador
