Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan, Hubei Province 430062, China.
Carbohydr Res. 2012 May 1;352:37-43. doi: 10.1016/j.carres.2012.01.025. Epub 2012 Feb 6.
A chitosanase-producing bacterium, Bacillus subtilis HD145 CCTCC AB 2010353, was isolated from a soil sample. The gene (csn) encoding chitosanase was cloned, sequenced, and expressed in the Pichia pastoris strain as a soluble and active form. Its expression level could be as high as 800 mg/L, and enzymatic activity reached approximately 9000 U/mg. The optimum pH and temperature were 5.5 and 50 °C, respectively. The recombinant protein was partially glycosylated. Its half lives at temperatures of 50 and 60 °C were 26 h and 23 min, respectively. Enzymatic activity was increased with an increasing degree of deacetylation of chitosan. The enzymatic productions of chitooligosaccharides from chitosans of various deacetylation degrees mainly ranged from chitobiose to chitopentamer.
一株产壳聚糖酶的细菌，解淀粉芽孢杆菌 HD145 CCTCC AB 2010353，从土壤样本中分离得到。壳聚糖酶的基因（csn）被克隆、测序，并在毕赤酵母菌株中以可溶性和活性形式表达。其表达水平可达 800mg/L，酶活约为 9000U/mg。最适 pH 和温度分别为 5.5 和 50°C。重组蛋白部分糖基化。其在 50°C 和 60°C 下的半衰期分别为 26h 和 23min。酶活性随壳聚糖脱乙酰度的增加而增加。各种脱乙酰度的壳聚糖的酶解产物主要为壳二糖到壳五糖。
