title: Tigerinins: novel antimicrobial peptides from the Indian frog Rana tigerina.
abstract: Four broad-spectrum, 11 and 12 residue, novel antimicrobial peptides have been isolated from the adrenaline-stimulated skin secretions of the Indian frog Rana tigerina. Sequences of these peptides have been determined by automated Edman degradation, by mass spectral analysis and confirmed by chemical synthesis. These peptides, which we have named as tigerinins, are characterized by an intramolecular disulfide bridge between two cysteine residues forming a nonapeptide ring. This feature is not found in other amphibian peptides. Conformational analysis indicate that the peptides tend to form beta-turn structures. The peptides are cationic and exert their activity by permeabilizing bacterial membranes. Tigerinins represent the smallest, nonhelical, cationic antimicrobial peptides from amphibians.
authors.affiliation: Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, 500 007, India.
authors.forename: K P
authors.initials: KP
authors.lastname: Sai
authors.forename: M V
authors.initials: MV
authors.lastname: Jagannadham
authors.forename: M
authors.initials: M
authors.lastname: Vairamani
authors.forename: N P
authors.initials: NP
authors.lastname: Raju
authors.forename: A S
authors.initials: AS
authors.lastname: Devi
authors.forename: R
authors.initials: R
authors.lastname: Nagaraj
authors.forename: N
authors.initials: N
authors.lastname: Sitaram
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000302:isolation & purification* / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000302:isolation & purification* / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009038:Motion; D009842:Oligopeptides / Q000302:isolation & purification* / Q000494:pharmacology; D011487:Protein Conformation; D011898:Ranidae; D012867:Skin / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D009842:Oligopeptides