title: Characterization of antimicrobial peptides from the skin secretions of the Malaysian frogs, Odorrana hosii and Hylarana picturata (Anura:Ranidae).
abstract: Peptidomic analysis of norepinephrine-stimulated skin secretions from Hose's rock frog Odorrana hosii (Boulenger, 1891) led to the isolation of 8 peptides with differential antibacterial activities. Structural characterization demonstrated that the peptides belonged to the esculentin-1 (1 peptide), esculentin-2 (1 peptide), brevinin-1 (2 peptides), brevinin-2 (2 peptides), and nigrocin-2 (2 peptides) families of antimicrobial peptides. Similar analysis of skin secretions from the Malaysian fire frog Hylarana picturata (Boulenger, 1920) led to the isolation and characterization of peptides belonging to the brevinin-1 (2 peptides), brevinin-2 (5 peptides), and temporin (1 peptide) families. The differences in antimicrobial activities of paralogous peptides provide insight into structure-activity relationships, emphasizing the importance of cationicity in determining potency. The substitution Lys11-->Gln in brevinin-1HSa (FLPAVLRVAAKIVPTVFCAISKKC) from O. hosii abolishes growth inhibitory activity against Escherichia coli but has no effect on the high potency (MIC = 8 microg/ml) against Staphylococcus aureus. In contrast, the substitution (Gly4-->Asp) in brevinin-2PTb (GFKGAFKNVMFGIAKSAGKSALNALACKIDKSC) from H. picturata reduces activity against both E. coli and S. aureus. Cladistic analysis based upon the amino acid sequences of the brevinin-2 peptides from Asian frogs provides evidence for sister taxon relationships between O. hosii and O. livida and between H. picturata and H. güntheri.
authors.affiliation: Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, 17666 Al-Ain, United Arab Emirates. jmc2016@qatar-med.cornell.edu
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
authors.forename: Jérôme
authors.initials: J
authors.lastname: Leprince
authors.forename: Hubert
authors.initials: H
authors.lastname: Vaudry
authors.forename: Laurent
authors.initials: L
authors.lastname: Coquet
authors.forename: Thierry
authors.initials: T
authors.lastname: Jouenne
authors.forename: Jay D
authors.initials: JD
authors.lastname: King
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001001:Anura / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012867:Skin / Q000378:metabolism*
chemical_list: D023181:Antimicrobial Cationic Peptides