皂苷鼠李糖苷酶RhaG和RhaD的酶反应特性研究

目的]研究皂苷鼠李糖苷酶RhaG和RhaD的酶反应特性。方法]对微生物Absidia sp.G3g菌产的人参皂苷糖苷酶（RhaG）和Absidia sp.D0d菌产的薯蓣皂苷糖苷酶（RhaD）分别进行分离纯化,并对2种提纯酶的分子量和酶性质进行了研究。结果]RhaG和RhaD的酶蛋白分子质量分别为61、56 kDa。RhaG的酶反应最适pH为5.0,pH稳定范围为3.0～7.0;最适温度为40℃,30～60℃温度稳定性较好;米式常数Km为9.523 mmol/L。RhaD的酶反应最适pH为5.0,pH稳定范围为3.0～7.0;最适温度为40℃,30～50℃温度稳定性较好;米式常数Km为8.834 mmol/L。结论]该研究为进一步探明2种酶间的差别奠定了基础。

Studies on Characteristics of Enzymatic Reaction of 2 Saponin Glycosidases RhaG and RhaD

Objective] The aim was to study the characteristics of enzymatic reaction of 2 saponin glycosidases RhaG and RhaD.Method] 2 saponin glycosidases RhaG and RhaD which were produced by microorganism Absidia sp.G3g and Absidia sp.D0d were isolated and purified,furthermore molecular weight and enzyme properties of RhaG and RhaD were studied.Result] Molecular weights of RhaG and RhaD were 61 and 56 kDa.As for RhaG,the optimum pH value of enzyme reaction was 5.0,and the stabilization range of pH value was 3.0-7.0;the optimum temperature was 40 ℃,and the stabilization range of temperature was 30-60 ℃;the Km was 9.523 mmol/L.As for RhaD,the optimum pH value of enzyme reaction was pH 5.0,and the stabilization range of pH value was 3.0-7.0;the optimum temperature was 40 ℃,and the stabilization range of temperature was 30-50 ℃;the Km was 8.834 mmol/L.Conclusion] The research provides a basis for studying the difference between the 2 saponin glycosidases.