【摘要】 从白曲霉菌A .Kawachii的米曲粗抽出液中 ,通过乙醇沉淀、离子交换层析、凝胶过滤层析等方式 ,获得了两个耐酸性α -淀粉酶比活性极高的组分 ,经SDS -PAGE分析 ,推断其组分A分子量为 85 ,0 0 0 ,组分B分子量为10 4 ,0 0 0。两组分均为糖蛋白 ,且能被枯草杆菌蛋白酶 (Subtilisin)适度降解。其N -末端 10 - 12残基的氨基酸序列与黑曲霉A .niger的耐酸性α -淀粉酶N -末端氨基酸序列极为相似。借此推断 ,A .Kawachii的白曲中至少有两种以上的耐酸性α -淀粉酶组分的存在更多还原

【Abstract】 By alcohol precipitation, DEAE Bio-Gal A ion exchange chromatography and Sephacryl S-300 gel chromatography, two components of high specific activity of acid stable α-amylase, component A and component B, were separated and purified from white qu extract. In the SDS-PAGE gel, the molecular weights of the purified component A and component B were estimated to be 85,000 and 104,000, respectively. And, it was found that both purified components were glycoprotein and were able to be digested into little protein molecular having the activity of acid stable α-amylase in the tests by subtilisin . In comparison with acid stable α-amylase of A. niger , the amino acid sequence of N-terminal 10～12 residues was quite similar. These results showed that there could be two types or more of acid stable α-amylase in the white qu originated from A. kawachii .更多还原