title: The structural organization of aurein precursor cDNAs from the skin secretion of the Australian green and golden bell frog, Litoria aurea.
abstract: Aureins are a family of peptides (13-25 residues), some of which possess potent antimicrobial and anti-cancer properties, which have been classified into 5 subgroups based upon primary structural similarities. They were originally isolated from the defensive skin secretions of the closely related Australian bell frogs, Litoria aurea and Litoria raniformis, and of the 23 aurein peptides identified, 10 are common to both species. Using a recently developed technique, we have constructed a cDNA library from the defensive secretion of the green and golden bell frog, L. aurea, and successfully cloned a range of aurein precursor transcripts containing entire open-reading frames. All open-reading frames consisted of a putative signal peptide and an acidic pro-region followed by a single copy of aurein. The deduced precursor structures for the most active aureins (2.2 and 3.1) confirmed the presence of a C-terminal amidation motif whereas that of aurein 5.3 did not. Processed peptides corresponding in molecular mass to aureins 2.2, 2.3, 2.5, 3.1 and 5.3 were identified in the same secretion sample using LC/MS. The application of this technique thus permits parallel peptidomic and transcriptomic analyses on the same lyophilized skin secretion sample circumventing sacrifice of specimens of endangered herpetofauna.
authors.affiliation: School of Pharmacy, Queen's University, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Tianbao
authors.initials: T
authors.lastname: Chen
authors.forename: Christopher
authors.initials: C
authors.lastname: Scott
authors.forename: Lijun
authors.initials: L
authors.lastname: Tang
authors.forename: Mei
authors.initials: M
authors.lastname: Zhou
authors.forename: Chris
authors.initials: C
authors.lastname: Shaw
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D023181:Antimicrobial Cationic Peptides; D001001:Anura; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry*; D008969:Molecular Sequence Data; D010455:Peptides; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D012867:Skin / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D018076:DNA, Complementary; D010455:Peptides; D012333:RNA, Messenger; C535241:aurein 2.5 peptide, Litoria aurea