北寄生凝集素的分离和性质研究

Isolation and Properties of Toxic Lectin formViscum coloratum(Bdjisheng).

采用酸处理Ｓｅｐｈａｒｏｓｅ６Ｂ亲和层析和ＳｅｐｈａｃｒｙｌＳ－２００凝胶过滤，首次从中药北寄生中分得一种有毒凝集素，称为北寄生凝集素（Ｖｉｓｃｕｍｃｏｌｏｒａｔｕｍｌｅｃｔｉｎ，ＶＣＬ），是一种高毒性的植物毒蛋白，对小鼠静脉给药的ＬＤ＿（５０）为４．４μｇ／ｋｇ，其粗提物也具有很强的毒性，对小鼠腹腔给药的ＬＤ＿（５０）为０．２ｇ／ｋｇ，分子量５２０００，等电点１０．５．

A Viscum coloratum lectin(VCL)was first separated from extracts of the stemsand leaves of Viscum coloratum Chinese,anordinary traditional medicine beijisheng,byaffinity chromatography on acid-treatedSepharose 6B and gel filtration on SephacrylS-200,with Mr=52 000,pI=10.5.TheLD_(50) was 4.4μg/kg for mice by intravenousinjection,It's a toxic protein obtained fromthe plant with higher toxicity to mice. Thecrude extracts of the poant also have strongtoxicity,because it's LD_(50) was 200 mg/kg formice by intraperitoneal injection and to be ex-pressed as the amount of dry materials.