title: Substrate specificity of two thrombin like enzymes (elegaxobin, elegaxobin II) from the venom of Trimeresurus elegans (Sakishima-habu), using neutralizing antibody.
abstract: We reported previously that elegaxobin and elegaxobin II cause the release of fibrinopeptide A alone from rabbit fibrinogen. Elegaxobin II is a thrombin-like enzyme that possesses kinin-releasing activity, and shows a characterization obviously different from elegaxobin. To study the substrate specificities of elegaxobin and elegaxobin II against fibrinogen, we investigated whether anti-elegaxobin or anti-elegaxobin II antibody counteracts those enzymatic activities. Anti-elegaxobin II antibody effectively counteracted the thrombin-like activity of elegaxobin and elegaxobin II in comparison to the anti-elegaxobin antibody. The anti-elegaxobin II antibody only counteracted the thrombin-like activity, whereas did not counteract TAME hydrolytic activity and weakly counteract the kinin-releasing activity. Furthermore, we investigated which part of elegaxobin II as an antigen this antibody connects with specifically, using M-peptides derived from digests with CNBr. As a result, anti-elegaxobin II antibody bound specifically to the M-peptide including C-terminal portion. In particular, the anti-elegaxobin II antibody connected to position 220-239 (AQPHEPGSYTNVFDHLDWIK), containing His(223).
authors.affiliation: Department of Hygenic Chemistry, Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204 8588, Japan.
authors.forename: Etsuko
authors.initials: E
authors.lastname: Oyama
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Takahashi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000737:chemistry / Q000494:pharmacology; D001666:Binding Sites, Antibody; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D005340:Fibrinogen / Q000737:chemistry; D007705:Kinins / Q000187:drug effects; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism; D011817:Rabbits; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000737:chemistry* / Q000276:immunology / Q000494:pharmacology; D013379:Substrate Specificity; D017841:Trimeresurus
chemical_list: D000906:Antibodies; D003435:Crotalid Venoms; D007705:Kinins; D010455:Peptides; D005340:Fibrinogen; D012697:Serine Endopeptidases; C408443:elegaxobin