海藻糖合成双酶体系酶性质及酶反应条件的研究

Study on enzymatic properties and reaction conditions in trehalose synthesis

通过对自筛出的一株微球菌 (Microccusroseus)进行海藻糖合成酶的性质及海藻糖合成的酶反应条件的研究 ,建立了使用粗酶不经纯化 ,直接进行酶反应的工艺流程 ,此工艺有可能进一步降低海藻糖的成本。研究得到了酶反应的一系列优化条件 :2 0 %细胞悬液 ,2 5℃下用 3 %甲苯处理 1h ;然后在 1 0 0mmol/L缓冲液中 ,pH值 8 0、30℃下与 5 %淀粉液化液进行酶反应2 4h ,得到海藻糖转化率达 75 %。研究了该酶体系的性质 ,发现该反应体系不存在底物和产物抑制 ,但存在对其产生抑制的金属离子 。

Studies on properties and reaction conditions of fucose ligase were made with a kind of Microccus roseus which was cultivated and chosen. The technology that was likely to cut down the cost of trehalose was established as crude enzyme can directly react without being purified. Enzymatic reaction conditions in a buffer system were optimized: 20% of cell suspension was treated with 3% of methylbenzene for 1 h at 25°C, then suspension reacted with 5% of starch in a 100 mmol/L (pH 8.0) buffer solution at 30°C. The highest conversion rate from 5% of starch to trehalose reached 75%. It's discovered that there is no substrate or product inhibition in the reaction, yet some metal ions exist that have inhibition to it. The exceptional activation of the enzymes was discovered as the trehalose was added.