麦冬多糖糖苷酶的分离纯化及其酶性质

Purification and characterization of Ophiopogon japonicus polysaccharide glycosidase

分离纯化了Absidiasp．O84s菌产的麦冬多糖糖苷酶，并对其酶性质进行了研究。结果表明，酶蛋白的分子质量为72ku，最适pH为5．0，在pH4．0～8．0范围内稳定。最适反应温度为40℃，在20～55℃范围内稳定。Ca＋、K＋、Na＋、Fe3＋、Mg2＋Zn2＋对该酶活性没有影响，Cu2＋对酶活力具有抑制作用。酶反应动力学参数Vmax=0．1315mmol／（h·L），Km=2．375mmol／L。

Polysaccharide glycosidase was purified and characterized from Absidia sp. O84s. Its molecular weight was 72 ku, and the optimum pH and temperature was pH 5.0 and 40℃. The glycosidase was stable at pH 4.0-8.0 and 20-50℃ respectively. Ions K＋, Zn2＋, Na＋, Mg2＋, Ca2＋ had no effect on the enzyme activity and Cu2＋ decreased enzyme activity. The kinetic analysis revealed that V was 0. 131 5 mmol/（h · L） and Km was 2. 375 mmol/L.