小麦内生枯草芽孢杆菌E1R-j胞外抗菌蛋白的分离纯化和性质  

Purification and Characterization of an Extracellular Antifungal Protein from Wheat Endophytic Bacillus subtilis Strain E1R-j

作　　者：黄保全[1] 黄丽丽[1] 康振生[1] 乔红萍[1] 

机构地区：[1]西北农林科技大学植保学院,陕西省农业分子生物学重点实验室,陕西杨凌712100

出　　处：《西北农业学报》2009年第6期285-290,共6页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：国家支撑计划项目(2006BAD08A05);高等学校学科创新引智计划资助项目(B07049);国家973项目(2006CB100203);国家自然科学基金项目(30270863)资助

摘　　要：通过（NH4）2SO4分级沉淀、疏水层析、PAGE切胶电洗脱、阴离子交换层析从E1R-j发酵滤液中分离纯化得到抗菌蛋白j1。经测定,j1分子量为51.9 kDa,等电点为8.7。j1不能催化昆布多糖、壳聚糖、羧甲基纤维素的水解;但能催化酪蛋白水解,其相对蛋白酶活性为384.67 U/mL。j1对蛋白酶K不敏感,具有很好的热稳定性（121℃）,在pH 5-9范围内表现稳定。对供试的5种病原真菌,j1仅对小麦全蚀病菌和苹果轮纹病菌有抑制作用。其中,对小麦全蚀菌的抑制中浓度IC50为0.14μg/mL。Clarifying the inhibitory mechanism of endophytic Bacillus subtilis E1R-j on Gaeumannomyces graminis var.tritici（Ggt） is fundamentally necessary for further efficient application of it in biological control of wheat take-all disease.Through Fractional Ammonia Sulfate Precipitation,Hydrophobic Interaction Chromatography,PAGE-Electro Elution and Ion Exchange Chromatography we have purified an antifungal protein from the fermentation filtrate of E1R-j which was designated as j1.It has an isoelectric point of 8.70 and an apparent molecular mass of 51.9 KDa as measured.J1 is unable to catalyze the hydrolysis of Laminarin,chitosan,carboxymethyl cellulose.But j1 can catalyze the hydrolysis of casein and the relative protease activity is measured 384.67 U/mL.j1 is resistant to protease K and is relatively stable between pH5.0 and 9.0 and at temperature below 121℃.According to the antifungal assay on 5 kinds of pathogenic fungi,j1 inhabits only apple ring rot and wheat take-all disease pathogens.The IC50 of j1 on Ggt was measured 0.14 μg/mL.

关 键 词：小麦全蚀 枯草芽孢杆菌 抗菌蛋白 生物防治 蛋白酶 

分 类 号：S435.121.49[农业科学—农业昆虫与害虫防治]