title: Flavorase, a novel non-haemorrhagic metalloproteinase in Protobothrops flavoviridis venom, is a target molecule of small serum protein-3.
abstract: Some venomous snakes possess anti-toxic proteins in their sera that may play a role in neutralizing the haemorrhagic factors or toxins in their own venom. Five small serum proteins (SSP-1-SSP-5) were isolated from the serum of Japanese viper (Protobothrops flavoviridis), and were found to act as self-defence proteins against the viper's own toxic components. However, the physiological function of SSP-3 has not been completely elucidated. Affinity chromatography of the venom on an SSP-3-immobilized column identified a novel 55-kDa protein as the target molecule of SSP-3. Sequences of internal fragments of this SSP-3-binding protein showed high homology to those of metalloproteinases from the P. flavoviridis venom. The cDNA sequence revealed that this protein, termed flavorase, is a P-III class metalloproteinase consisting of 423 amino acid residues. The purified protein did not show haemorrhagic and cytotoxic activity. Biacore measurements revealed that SSP-3 was bound to flavorase with a dissociation constant of 6.4 × 10(-9) M. SSP-3 non-competitively inhibited the peptidase activity of flavorase with an inhibition constant of 6.6 × 10(-9) M.
authors: Department of Chemistry, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan anarumi@fukuoka-u.ac.jp.
authors: Narumi
authors: N
authors: Shioi
authors: Department of Chemistry, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan.
authors: Ayumi
authors: A
authors: Nishijima
authors: Department of Chemistry, Faculty of Science, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan.
authors: Shigeyuki
authors: S
authors: Terada
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism*; D045726:Metalloproteases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D012910:Snake Venoms / Q000201:enzymology*; D012911:Snakes
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D012910:Snake Venoms; D045726:Metalloproteases
keywords: Protobothrops flavoviridis serum; protein interaction; proteinase inhibitor; small serum protein; snake venom metalloproteinase