雪山豆(Phaseolus sp.)凝集素的亲和层析纯化与其部分性质

 用猪甲状腺球蛋白-对氨基苯砜乙基-交联琼脂作亲和吸附剂,可对雪山豆(Phaseolus sp.)凝集素进行亲和层析纯化。纯化后的凝集素在聚丙烯酰胺凝胶电泳中显示单一蛋白质带。Sephadex G-100凝胶层析法测得分子量为65,000道尔顿,SDS-聚丙烯酰胺凝胶电泳表明该凝集素分子仅有一个分子量为65,000道尔顿的亚基,酚-硫酸法测得总糖含量为4.6％,氨基酸组成分析表明雪山豆凝集素富含门冬氨酸,而甲硫氨酸含量甚少。该凝集素是强促有丝分裂原,对人外周血中淋巴细胞的转化率大于90％,细胞分裂比率达12％。雪山豆凝集素不仅能凝集多种动物红细胞,还能凝集人精细胞。经体外实验表明,雪山豆凝集素对人肝癌细胞有抑制作用。

ISOLATION AND CHARACTERIZATION OF THE LECTIN FROM SNOW MOUNTAIN BEAN(Phaseolus sp.)

A glycoprotein, designated Snow Mountain-bean Lectin (SML) , was isolat d from the seeds of Snow Mountain-bean (Phaseolus sp.)by affinity chromatography on porcine thyroglobulin-cross-linked agar column.The purified lectin is homogeneous on disc electrophoresis.The molecular weight estimated by gel filtration on Sephadex G-100 and SDS-PAGE is 65,000.The saccharide content of SML is 4.6% as measure by the phenol-sulfuric acid method.It contains rich amounts of Aspar-tic acid and a little of Methionine. SML is a very strong mitogen for human peripheral lymphocytes. It agglutinates rabbit erythrocytes at a concentration as low as 0.98/μg/ml, and also agglutinates human sperm. Inhibition of human hepatoma cells in vitro has been suggested for SML.