苦瓜籽核糖体失活蛋白的基本性质研究

Study on the Characteristics and Biological Activity of Ribosome Inactivating Protein from Momordica Charantia

采用 Affi- Gel亲和层析和 Sephacryl S- 10 0分子筛层析等方法获得苦瓜籽核糖体失活蛋白 (RIP) ,经 SDS- PAGE,PAGE,IEF和 PAS方法分析均表明为单一蛋白着色带或单一糖蛋白着色带 .根据 SDS- PAGE测得表观分子量为 30 0 0 0 ,经 IEF- PAGE结果计算其 PI为 9.0 ,对无细胞系统中蛋白质生物合成抑制活性明显 ,其 IC50 为 5.3× 10 -10 mol/ L左右 .体外生物活性试验结果表明其对人肝癌细胞 ,Vero,SP2 / 0 ,3T3,Kb,Navana,S- 180等肿瘤细胞株和麻疹病毒均表现有不同程度的抑制作用 ,而对完整人胚肺二倍体细胞却毒性极小 .

The RIP from momordica charantia was isolated and purified by fractionation of 30% 65% saturation of (NH 4) 2SO 4 followed by Affinity chromatography on Affi Gel and Sephacryl S 100HR molecular sieve chromatography.The results of SDS AGE,PAGE,IEF PAGE and PAS Schiff staining after SDS PAGE showed that RIP was a homogeneous single band or a glycoprotein band with PI of about 9.0.The molecular weight of 30 000 was determined by SDS PAGE.The total neutral sugar content of purified RIP expressed as mannose was 1.53%.The RIP has a powerful inhibitory action upon protein synthesis when IC 50 is 5.3×10 -10 mol/L in reticulocyte lysate.The activities of antitumor and antivirus and cytotoxicity on intact cell were studied too.These findings suggest that the RIP may be an useful agent in the treatment of certain tumors and virus infection.