Wang J H, Liu Y Y, Yao B, Wang Y R
Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing.
Sheng Wu Gong Cheng Xue Bao. 2000 Jan;16(1):60-4.
A yeast strain Kluyveromyces with high inulinase yield was screened. The highest inulinase activity of 288.78 u/mL was reached when a high cell density cultivation method was developed for inulinase production. It was 6.8 times higher than the highest level reported in the same species. The activity ratio of its inulinase to invertase was 1/24.72, the Km values were 13.3 mmol/L and 62.6 mmol/L when inulin and sucrose were used as substrate, respectively; The optimum pH value was 4.4, this enzyme also showed a good pH adaptability and stability, i.e. more 90% of the highest level was maintained between pH 3.8 and 5.6; The optimum reaction temperature was 55 degrees C, higher activity was maintained between 50-57.5 degrees C, its half life period was 16 hours at 55 degrees C; It was found for the first time that addition of magnesium ion into the reaction system increased the enzyme activity by 11%.
筛选出一株菊粉酶产量高的酵母菌株克鲁维酵母。当开发出一种用于菊粉酶生产的高细胞密度培养方法时，菊粉酶的最高活性达到288.78 u/mL。这比同一物种中报道的最高水平高6.8倍。其菊粉酶与转化酶的活性比为1/24.72，以菊粉和蔗糖为底物时，Km值分别为13.3 mmol/L和62.6 mmol/L；最适pH值为4.4，该酶还表现出良好的pH适应性和稳定性，即在pH 3.8至5.6之间保持最高水平的90%以上；最适反应温度为55℃，在50-57.5℃之间保持较高活性，在55℃下其半衰期为16小时；首次发现向反应体系中添加镁离子可使酶活性提高11%。
