title: Novel bradykinins and their precursor cDNAs from European yellow-bellied toad (Bombina variegata) skin.
abstract: Two novel bradykinin-related peptides (Ala3,Thr6)-bradykinin and (Val1,Thr3,Thr6)-bradykinin, were identified by a systematic sequencing study of peptides in the defensive skin secretion of the yellow-bellied toad, Bombina variegata. These peptides are the first amphibian skin bradykinins to exhibit amino acid substitutions at the Pro3 position of the bradykinin nonapeptide. Previously reported bradykinins from other Bombina species were not detected. Respective precursor cDNAs, designated BVK-1 and BVK-2, respectively, were cloned from a skin library by 3'- and 5'-RACE reactions. BVK-1 contained an open-reading frame of 97 amino acids encoding a single copy of (Ala3,Thr6)-bradykinin and similarly, the open-reading frame of BVK-2 consisted of 96 amino acids encoding a single copy of (Val1,Thr3,Thr6)-bradykinin. Synthetic replicates of each novel bradykinin were found to be active on mammalian arterial and small intestinal smooth muscle preparations. The structural diversity of bradykinins in amphibian defensive skin secretions may be related to defence against specific predators.
authors.affiliation: School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK; The Institute of Biotechnology, Fuzhou University, Fujian Province, People's Republic of China.
authors.forename: Tianbao
authors.initials: T
authors.lastname: Chen
authors.forename: David F
authors.initials: DF
authors.lastname: Orr
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Bjourson
authors.forename: Stephen
authors.initials: S
authors.lastname: McClean
authors.forename: Martin
authors.initials: M
authors.lastname: O'Rourke
authors.forename: David G
authors.initials: DG
authors.lastname: Hirst
authors.forename: Pingfan
authors.initials: P
authors.lastname: Rao
authors.forename: Chris
authors.initials: C
authors.lastname: Shaw
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001001:Anura; D001483:Base Sequence; D001920:Bradykinin / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D018076:DNA, Complementary; D008297:Male; D008969:Molecular Sequence Data; D009130:Muscle, Smooth / Q000502:physiology; D011498:Protein Precursors / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D016415:Sequence Alignment; D012867:Skin / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D011498:Protein Precursors; D001920:Bradykinin