【摘要】 裸仁南瓜籽经破碎,磷酸缓冲液4℃浸提,硫酸铵沉淀,上清液透析,SP-Sepharose FF阳离子交换层析,Sephadex G-75凝胶层析柱,冻干等步骤纯化得到一种新的抗真菌蛋白,命名为Pw-1,并对其抗菌活性进行初步鉴定。SDS-PAGE分析显示Pw-1蛋白的分子质量约为14.8 ku。抗菌活性鉴定表明,该蛋白对黄瓜枯萎病菌、大豆灰斑病菌和链格孢霉菌3株真菌具有显著的生长抑制活性,并呈现出剂量依赖的特征,IC50值分别为16.64、20.91和21.22μmol/L。加入胰蛋白酶后Pw-1蛋白的抗菌活性消失,表现出蛋白类物质所具有的对于蛋白酶的敏感性。更多还原

【Abstract】 A novel antifungal protein is measured to be isolated from pumpkin seeds and designated Pw- 1. The purification procedure consists of extraction with phosphoric acid buffer at 4 ℃,ammonium sulfate precipitation, dialysis,SP- Sepharose FF column,Sephadex G- 75 column,freeze drying and other processes. Partial characterization and antifungal activity are assayed in the paper. The molecular mass of the purified Pw- 1 was determined as 14. 8 ku by SDS- PAGE. The protein exhibited antifungal activity to the Fusarium oxysporum,Cercospora sojina Hara,and Alternaria alternata in a dose- dependent with IC50values of 16. 64,20. 91,and 21. 22 μmol / L respectively. The antifungal activity of Pw- 1 protein disappeared after trypsin addition,showing the protease sensitivity of protein.更多还原