对毕赤酵母表达β-1，3—1，4-葡聚糖酶条件进行优化，在摇瓶水平上研究了温度、pH、甲醇流加量、诱导时间，油酸等因素对重组葡聚糖酶的影响；得优化条件为：最适温度30℃、pH6．0，最佳甲醇诱导浓度为0．5％，最佳诱导时间为84h，酶活力达27．4U／mL，比初始酶活力提高了1．9倍。酶反应的最适pH为6．0，最适温度为50℃。在pH3．5—8．0的范围内和温度55℃以下保存时具有较好的稳定性；其中，CaCl2对重组酶的激活效果显著，使酶活力提高达92％。%In this word, the express conditions ofβ - 1, 3 - 1, 4 - glucanase are optimized in Pichia pastoris. By the shakeing flask, the infuluences of temperature, pH, methanol, inducing time, oleic acid on the expression of glucanase were investigated. The results show that the optimal cultural conditions were temperature 30℃, pH6.0, and best methanol con- centration was 0.5%, induction time for 84 h, enzyme activity reached 27.4 U/mL. The optimal reaction pH and tempera- ture of glucanase were 6.0 and 50℃ respectively. The enzyme was stable within pH3.5 - 8.0 under 60℃. Furthermore, CaC12 can significantly improve the enzyme activity, make the enzyme activity increase 92%.
展开▼
