title: Molecular cloning and antifibrinolytic activity of a serine protease inhibitor from bumblebee (Bombus terrestris) venom.
abstract: Bumblebee (Bombus spp.) venom contains a variety of components, including bombolitin, phospholipase A(2) (PLA(2)), serine proteases, and serine protease inhibitors. In this study, we identified a bumblebee (Bombus terrestris) venom serine protease inhibitor (Bt-KTI) that acts as a plasmin inhibitor. Bt-KTI consists of a 58-amino acid mature peptide that displays features consistent with snake venom Kunitz-type inhibitors, including six conserved cysteine residues and a P1 site. Recombinant Bt-KTI was expressed as a 6.5-kDa peptide in baculovirus-infected insect cells. The recombinant peptide demonstrated properties similar to Kunitz-type trypsin inhibitors. Bt-KTI showed no detectable inhibitory effects on factor Xa, thrombin, or tissue plasminogen activator; however, Bt-KTI strongly inhibited plasmin, indicating that it acts as an antifibrinolytic agent. These findings demonstrate the antifibrinolytic role of Bt-KTI as a plasmin inhibitor.
authors.affiliation: College of Natural Resources and Life Science, Dong-A University, Busan 604-714, Republic of Korea.
authors.forename: Yuling
authors.initials: Y
authors.lastname: Qiu
authors.forename: Kwang Sik
authors.initials: KS
authors.lastname: Lee
authors.forename: Young Moo
authors.initials: YM
authors.lastname: Choo
authors.forename: Dexin
authors.initials: D
authors.lastname: Kong
authors.forename: Hyung Joo
authors.initials: HJ
authors.lastname: Yoon
authors.forename: Byung Rae
authors.initials: BR
authors.lastname: Jin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000933:Antifibrinolytic Agents / Q000737:chemistry / Q000494:pharmacology*; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D001514:Bee Venoms / Q000235:genetics / Q000378:metabolism*; D001516:Bees / Q000502:physiology*; D003001:Cloning, Molecular; D004338:Drug Combinations; D024202:Electrophoretic Mobility Shift Assay / Q000379:methods; D005341:Fibrinolysin / Q000037:antagonists & inhibitors / Q000494:pharmacology; D015870:Gene Expression; D019476:Insect Proteins / Q000235:genetics / Q000494:pharmacology; D007313:Insecta; D008969:Molecular Sequence Data; D011994:Recombinant Proteins; D016415:Sequence Alignment; D015842:Serine Proteinase Inhibitors / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology*; D013917:Thrombin / Q000187:drug effects
chemical_list: D000933:Antifibrinolytic Agents; D001514:Bee Venoms; D004338:Drug Combinations; D019476:Insect Proteins; D011994:Recombinant Proteins; D015842:Serine Proteinase Inhibitors; D013917:Thrombin; D005341:Fibrinolysin