title: Two novel Bv8-like peptides from skin secretions of the toad Bombina maxima.
abstract: Two novel bioactive peptides were purified from skin secretions of the toad Bombina maxima. The partial N-terminal sequences of these two peptides were determined by automated Edman degradation. This allowed the cloning of full-length cDNAs encoding these two peptides from a cDNA library prepared from the toad skin. The deduced complete amino acid sequences indicate that both peptides are composed of 77 amino acids. A FASTA search in the databanks revealed that they exhibit 86-91% sequence identity with Bv8, a peptide originally isolated from skin secretions of Bombina variegata. They were thus named as Bv8-like peptide 1 (Bv8-LP1) and Bv8-like peptide 2 (Bv8-LP2), respectively. Sequence differences between Bv8-LP1 and 2 were due to six amino acid substitutions at positions 6, 11, 23, 24, 62 and 63. Bv8-LP1 and 2 differed from Bv8 with eleven and seven amino acid substitutions, respectively. Like Bv8, Bv8-LP1 and 2 possessed contractile activity on isolated guinea pig ileum. Additionally, they stimulated contraction of rabbit aortic rings in a dose-dependent manner at nanomolar concentrations.
authors.affiliation: Department of Animal Toxinology, Kunming Institute of Zoology, The Chinese Academy of Sciences, 32 East Jiao Chang Road, Kunming, Yunnan 650223, PR China.
authors.forename: Ren
authors.initials: R
authors.lastname: Lai
authors.forename: Hen
authors.initials: H
authors.lastname: Liu
authors.forename: Wen Hui
authors.initials: WH
authors.lastname: Lee
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D029845:Amphibian Proteins; D000818:Animals; D001001:Anura / Q000235:genetics*; D001013:Aorta, Thoracic / Q000187:drug effects / Q000502:physiology; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D005260:Female; D015723:Gene Library; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D008969:Molecular Sequence Data; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D009479:Neuropeptides; D011506:Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000494:pharmacology; D011817:Rabbits; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA / Q000379:methods; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000737:chemistry* / Q000378:metabolism; D013997:Time Factors; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D029845:Amphibian Proteins; C121344:Bv8 protein, Bombina variegata; D018076:DNA, Complementary; D009479:Neuropeptides; D011506:Proteins