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被尖吻蝮蛇咬伤会引起严重的出血,对蛇毒出血毒素的研究有利于治疗蛇伤出血药物的筛选.通过SephadexG-75,DEAE-SephadexA-50,SephadexG-200和两次PBE聚焦层析,从尖吻蝮蛇(Dienagkistrodonacutus)蛇毒中纯化到一个分子量为56000的出血毒素(DaHT-3),经氨基酸组成测定计算,由487个氨基酸残基组成.此成分在SDS-PAGE上显示出一条均一的蛋白染色带,用等电聚焦电泳测定,其pI为5.50.该出血成分的最小出血剂量是2.6μg,具有蛋白水解酶活力,其活力为3.68,但没有精氨酸酯酶和磷脂酶A2活力.用红外光谱仪研究DaHT-3在溶液中酰胺I带的吸收谱,该毒素含有31.8%的α螺旋、56.1%的β折叠和12.1%的转角;当加入EDTA螯合剂去除金属离子后,它们的α螺旋、β折叠、转角和无规卷曲分别变为11%、26.4%、46.2%和16.5%,而出血活力和蛋白水解酶活力均丧失,表明该出血毒素是金属蛋白酶
Serious bleeding was caused by bites of Agkistrodon acutus, and the study on the venom toxins could be used to screen the drug for the treatment of snakebite hemorrhage.Sephadex G-75, DEAE-Sephadex A-50, Sephadex G-200 and twice PBE , Purified from Dienagistrodonacutus snake venom to a Dahexolysis-induced toxoid (DaHT-3) with a molecular weight of 56,000 and composed of 487 amino acid residues calculated on the basis of the amino acid composition.This component shows one A homogeneous protein staining band, determined by isoelectric focusing, had a pI of 5.50.The minimum bleeding dose for this bleed component was 2.6 μg with proteolytic activity of 3.68 but no arginine esterase and phospholipase A2 activity. The absorbance spectrum of DaI-3 in amido I band in solution was studied by IR spectroscopy. The toxin contained 31.8% alpha helix, 56.1% beta sheet and 12.1% turn angle. When adding EDTA chelating agent to remove metal ions, Their α-helices, β-sheets, turns and random coils became 11%, 26.4%, 46.2% and 16.5%, respectively, with loss of both hemorrhagic and proteolytic activities, indicating that the toxin is a metalloprotease