title: Antimicrobial peptides from the skins of North American frogs.
abstract: North America is home to anuran species belonging to the families Bufonidae, Eleutherodactylidae, Hylidae, Leiopelmatidae, Ranidae, and Scaphiopodidae but antimicrobial peptides have been identified only in skin secretions and/or skin extracts of frogs belonging to the Leiopelmatidae ("tailed frogs") and Ranidae ("true frogs"). Eight structurally-related cationic alpha-helical peptides with broad-spectrum antibacterial activity, termed ascaphins, have been isolated from specimens of Ascaphus truei (Leiopelmatidae) occupying a coastal range. Characterization of orthologous antimicrobial peptides from Ascaphus specimens occupying an inland range supports the proposal that this population should be regarded as a separate species A. montanus. Ascaphin-8 shows potential for development into a therapeutically valuable anti-infective agent. Peptides belonging to the brevinin-1, esculentin-1, esculentin-2, palustrin-1, palustrin-2, ranacyclin, ranatuerin-1, ranatuerin-2, and temporin families have been isolated from North American ranids. It is proposed that "ranalexins" represent brevinin-1 peptides that have undergone a four amino acid residue internal deletion. Current taxonomic recommendations divide North American frogs from the family Ranidae into two genera: Lithobates and Rana. Cladistic analysis based upon the amino acid sequences of the brevinin-1 peptides provides strong support for this assignment.
authors.affiliation: Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, 17666 Al-Ain, United Arab Emirates. jmconlon@uaeu.ac.ae
authors.forename: J Michael
authors.initials: JM
authors.lastname: Conlon
authors.forename: Jolanta
authors.initials: J
authors.lastname: Kolodziejek
authors.forename: Norbert
authors.initials: N
authors.lastname: Nowotny
mesh_terms: D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000302:isolation & purification* / Q000494:pharmacology; D000818:Animals; D000890:Anti-Infective Agents / Q000302:isolation & purification* / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000302:isolation & purification* / Q000494:pharmacology; D008969:Molecular Sequence Data; D011506:Proteins / Q000302:isolation & purification / Q000494:pharmacology; D011898:Ranidae / Q000145:classification / Q000378:metabolism*; D012867:Skin / Q000737:chemistry*
chemical_list: D029845:Amphibian Proteins; D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D011506:Proteins; C104501:temporin; C078413:brevinin-1 protein, Rana; C078414:brevinin-2, Rana