Peptidomic analysis of the host-defense peptides in skin secretions of the Amazon River frog Lithobates palmipes (Ranidae) Antimicrobial Peptides; Phylogeny; Amphibia; Proline; Tree article 2023 CC BY 4.0 International http://creativecommons.org/licenses/by/4.0/ eng doi:10.1016/j.cbd.2023.101069 https://phaidra.vetmeduni.ac.at/o:3365 Mechkarska, Milena (University of the West Indies) Conlon, J. Michael (University of Ulster) Nowotny, Norbert (University of Veterinary Medicine Vienna / Mohammed Bin Rashid University of Medicine and Health Sciences) Jouenne, Thierry (Université de Rouen Normandie) Leprince, Jérôme (Université de Rouen Normandie) Coquet, Laurent (Université de Rouen Normandie) Barran, Gervonne (University of the West Indies) Kolodziejek, Jolanta (University of Veterinary Medicine Vienna) Skin secretions of certain frog species represent a source of host-defense peptides (HDPs) with therapeutic potential and their primary structures provide insight into taxonomic and phylogenetic relationships. Peptidomic analysis was used to characterize the HDPs in norepinephrine-stimulated skin secretions from the Amazon River frog Lithobates palmipes (Ranidae) collected in Trinidad. A total of ten peptides were purified and identified on the basis of amino acid similarity as belonging to the ranatuerin-2 family (ranatuerin-2PMa, -2PMb, -2PMc, and-2PMd), the brevinin-1 family (brevinin-1PMa, -1PMb, -1PMc and des(8-14)brevinin-1PMa) and the temporin family (temporin-PMa in C-terminally amidated and non-amidated forms). Deletion of the sequence VAAKVLP from brevinin-1PMa (FLPLIAGVAAKVLPKIFCAISKKC) in des[(8-14)brevinin-1PMa resulted in a 10-fold decrease in potency against Staphylococcus aureus (MIC = 31 μM compared with 3 μM) and a > 50-fold decrease in hemolytic activity but potency against Echerichia coli was maintained (MIC = 62.5 μM compared with 50 μM). Temporin-PMa (FLPFLGKLLSGIF.NH2) inhibited growth of S. aureus (MIC = 16 μM) but the non-amidated form of the peptide lacked antimicrobial activity. Cladistic analysis based upon the primary structures of ranaturerin-2 peptides supports the division of New World frogs of the family Ranidae into the genera Lithobates and Rana. A sister-group relationship between L. palmipes and Warszewitsch's frog Lithobates warszewitschii is indicated within a clade that includes the Tarahumara frog Lithobates tarahumarae. The study has provided further evidence that peptidomic analysis of HDPs in frog skin secretions is a valuable approach to elucidation of the evolutionary history of species within a particular genus. application/pdf Comparative Biochemistry and Physiology D - Genomics and Proteomics 46 (2023) Elsevier