摘要
通过DEAE-Sepharose离子交换分段层析,DEAE-Sepharose离子交换梯度层析和Sephadex G-100凝胶过滤层析三种方法的联用从中华白玉蜗牛消化酶中分离出一种人参皂苷Rb1水解酶。分离后该酶在SDSPAGE上呈单一蛋白质条带。应用SDSPAGE和凝胶过滤层析对分子量的测定,提示该酶是由4个分子量为110～115kD的相同亚基组成的同源四聚体。Rb1为底物的动力学参数Km和Vmax分别为0.790mmolL和10.192μmolminmg。该酶对人参皂苷Rb1糖键进行有选择的水解,可水解人参皂苷Rb1C20位的一个糖苷键生成人参皂苷Rd。
Through a combination of twice DEAE chromatography by NaCl stepwise and gradient elution with gel filtration chromatography, a kind of ginsenoside-Rb1 hydrolase from crude Helix snailase was separated. The hydrolase was purified to apparent homogeneity on SDS-PAGE, It was estimated that the purified hydrolase was consisted of four identical subunits with a molecular mass of 110- 115kD by SDS-PAGE and gel filtration chromatography. The Km and Vmax values for ginsenoside-Rb1 were calculated to be 0.790mmol/L and 10.192μmol/（min·mg） of protein respectively, The ginsenoside-Rb1 hydrolase could only hydrolyze the glycosidic bond at the C20 position of ginsenoside-Rb1 into ginsenoside-Rd.
出处
《生物工程学报》
CAS
CSCD
北大核心
2005年第6期929-933,共5页
Chinese Journal of Biotechnology
基金
国家重点基础研究发展计划(No.2003CB716005)
中国科学院知识创新工程前沿领域项目(No.K2002A14)
大连市科学技术基金(No.2002229)资助。~~
