摘要
研究了脆壁克鲁维酵母菌乳糖酶的性质 ,该酶作用最适 pH在 6 5～ 7 0 ,最适温度为 37℃ ,5 0℃保温 15min残留酶活为 84 0 2 % ,该酶在 pH 5 8～ 7 3范围内比较稳定 ,以ONPG和乳糖为底物的米氏常数为1 16mmol/L和 5 6 3mmol/L ,Mn2 + ,Mg2 + ,Na+ ,K+ 及微量Ca2 +
The optimum pH and temperature for the enzyme lactase isolated from the yeast kluyveromyces fragilis was found to be in the range of 6 5～7 0 and 37 ℃, respectively. Incubating enzyme at 50 ℃ for 15 min,the residue activity was measured as 84 02%. The enzyme shows stability in pH range of 5 8～7 3 .The lactase has Km value of 1 16 mmol/L and 5 63 mmol/L for ONPG and lactose respectively. Metal ions such as Mn 2+ ,Mg 2+ ,Na +,K + and low concentration of Ca 2+ have an activating effect on enzyme acivity.
出处
《药物生物技术》
CAS
CSCD
2000年第3期153-156,共4页
Pharmaceutical Biotechnology
