Zhu Xu-Fen, Wu Xiao-Yun, Dai Yun
College of Life Science, Zhejiang University, Hangzhou, Zhejiang 310012, People's Republic of China.
Biosci Biotechnol Biochem. 2003 Feb;67(2):284-90. doi: 10.1271/bbb.67.284.
A species of bacterium with high chitosanase activity was isolated from soil samples in Haiyan City, China, and identified as an Acinetobacter species. This strain, named Acinetobacter sp. strain C-17, produced a chitosanase that was inducible and secreted into the medium. The optimal conditions for enzyme production were cells used to inoculate a medium containing 1% chitosan (pH 7.0) followed by culture at 30 degrees C. The chitosanase activity reached 1.7 U/ml when strain C-17 was incubated in a 250-ml flask under the optimal conditions for 24 h, and reached 2.8 U/ml when cells were incubated in a 3-l fermentor. The optimal pH and temperature for hydrolysis of chitosanase were 7.0 and 36 degrees C, respectively. The chitosanase activity was stable in the pH range of 5-8 and temperature range of 30-40 degrees C. The chitosanase of the strain was extracted by zinc acetate and ammonium sulfate precipitation. The molecular mass was estimated to be 35.4 kDa by SDS-PAGE.
从中国海盐市的土壤样本中分离出一种具有高壳聚糖酶活性的细菌，鉴定为不动杆菌属。该菌株命名为不动杆菌属菌株C-17，产生一种可诱导并分泌到培养基中的壳聚糖酶。产酶的最佳条件是将细胞接种到含有1%壳聚糖（pH 7.0）的培养基中，然后在30℃下培养。当菌株C-17在250毫升烧瓶中于最佳条件下培养24小时时，壳聚糖酶活性达到1.7 U/ml，当细胞在3升发酵罐中培养时，活性达到2.8 U/ml。壳聚糖酶水解的最佳pH和温度分别为7.0和36℃。壳聚糖酶活性在pH 5-8和温度30-40℃范围内稳定。该菌株的壳聚糖酶通过醋酸锌和硫酸铵沉淀提取。通过SDS-PAGE估计其分子量为35.4 kDa。
