禾黑芽枝霉诱变体果胶酶的分离纯化和理化特性

THE PURIFICATION AND CHARACTERIZATION OF PECTINASES FROM CLADOSPORIUM HERBARUM AND ITS MUTANS

通过淀粉变性处理，超过滤及离子交换葡聚糖凝胶梯度色谱法，从突变菌株GBIBU7发酵液中分离出30余种蛋白质组分．经测试其中三种是果胶酶，分别命名为PⅠ，PⅡ和PⅢ．测定了三种果胶酶的动力学参数．其最适反应温度分别为45℃，35℃和45℃，最适pH值分别为4．4，5．0和5．0，它们的Km和Vmax分别为27．8μM，593U；18．8μM，1259U；27．7μM和4914U．分子量分别为64KD，66KD和46KD．这三种果胶酶都是糖蛋白，测定了它们的氨基酸和单糖的构成．

More than 30 components from the products of fermentation with Cladosporium herbarem mubot were isolated after stafch denature, ultrofiltration and gradient ion-exchange Sephadex chromatography, 3 of which are pectinases named as PⅠ, PⅡ, and PⅢ, seperately. The kinetics of the emymes were studied. The results are as follow:the temperature, pH for optimal reaction, Km, and Vmax were 45℃ , 35℃, and 45℃, 4.4, 5.0, and 5.0, 27.8 μM,18.8μM, and 27.7μM, 593 U, 1259 U, and 4 914 U for PⅠ, PⅡ, and PⅢ, respectively. The molecular weights of the 3 enzpoes were 64 KD, 66 KD,and 46 KD. The 3 pectinases were glycoproteins and their components were analyzed.