title: Primary structures of skin antimicrobial peptides indicate a close, but not conspecific, phylogenetic relationship between the leopard frogs Lithobates onca and Lithobates yavapaiensis (Ranidae).
abstract: The phylogenetic relationship between the relict leopard frog Lithobates (Rana) onca (Cope, 1875) and the lowland leopard frog Lithobates (Rana) yavapaiensis (Platz and Frost, 1984) is unclear. Chromatographic analysis of norepinephrine-stimulated skin secretions from L. onca led to the identification of six peptides with antimicrobial activity. Determination of their primary structures indicated that four of the peptides were identical to brevinin-1Ya, brevinin-1Yb, brevinin-1Yc and ranatuerin-2Ya previously isolated from skin secretions of L. yavapaiensis. However, a peptide belonging to the temporin family (temporin-ONa: FLPTFGKILSGLF.NH(2)) and an atypical member of the ranatuerin-2 family containing a C-terminal cyclic heptapeptide domain (ranatuerin-2ONa: GLMDTVKNAAKNLAGQMLDKLKCKITGSC) were isolated from the L. onca secretions but were not present in the L. yavapaiensis secretions. Ranatuerin-2ONa inhibited the growth of Escherichia coli (MIC=50muM) and Candida albicans (MIC=100muM ) and showed hemolytic activity (LC(50)=90muM) but was inactive against Staphylococcus aureus. The data indicate a close phylogenetic relationship between L. onca and L. yavapaiensis but suggest that they are not conspecific species.
authors.affiliation: Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, 17666 Al-Ain, United Arab Emirates.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Conlon
authors.forename: Laurent
authors.initials: L
authors.lastname: Coquet
authors.forename: Jérôme
authors.initials: J
authors.lastname: Leprince
authors.forename: Thierry
authors.initials: T
authors.lastname: Jouenne
authors.forename: Hubert
authors.initials: H
authors.lastname: Vaudry
authors.forename: Jay D
authors.initials: JD
authors.lastname: King
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry*; D002176:Candida albicans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry* / Q000302:isolation & purification; D010802:Phylogeny; D011898:Ranidae / Q000235:genetics*; D012867:Skin / Q000737:chemistry*
chemical_list: D023181:Antimicrobial Cationic Peptides; D010455:Peptides