School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China; Key Laboratory of Marine Biology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
School of Marine Science and Technology, Huaihai Institute of Technology, Lianyungang, Jiangsu 222005, China; Jiangsu Marine Resources Development Research Insititute, Lianyungang, Jiangsu 222005, China.
Carbohydr Polym. 2014 Jun 15;106:71-6. doi: 10.1016/j.carbpol.2014.01.102. Epub 2014 Feb 8.
Dextranases can hydrolyze dextran deposits and have been used in the sugar industry. Microbial strains which produce dextranases for industrial use are chiefly molds, which present safety issues, and dextranase production from them is impractically long. Thus, marine bacteria to produce dextranases may overcome these problems. Crude dextranase was purified by a combination of ammonium sulfate fractionation and ion-exchange chromatography, and then the enzyme was characterized. The enzyme was 66.2 kDa with an optimal temperature of 50°C and a pH of 7. The enzyme had greater than 60% activity at 60°C for 1h. Moreover, 10mM Co(2+) enhanced dextranase activity (196%), whereas Ni(2+) and Fe(3+) negatively affected activity. 0.02% xylitol and 1% alcohol enhanced activity (132.25% and 110.37%, respectively) whereas 0.05% SDS inhibited activity (14.07%). The thickness of S. mutans and mixed-species oral biofilm decreased from 54,340 nm to 36,670 nm and from 64,260 nm to 43,320 nm, respectively.
葡聚糖酶可以水解葡聚糖沉积物，已被应用于制糖工业。用于工业生产的葡聚糖酶主要来源于霉菌，但霉菌存在安全问题，且其生产周期长。因此，利用海洋细菌生产葡聚糖酶可能会克服这些问题。粗葡聚糖酶通过硫酸铵分级沉淀和离子交换层析进行纯化，然后对酶进行了特性分析。该酶的分子量为 66.2 kDa，最适温度为 50°C，最适 pH 值为 7。该酶在 60°C 下孵育 1 小时后仍保持超过 60%的活性。此外，10mM 的 Co(2+)能增强葡聚糖酶的活性（提高 196%），而 Ni(2+)和 Fe(3+)则会降低其活性。0.02%的木糖醇和 1%的乙醇分别能增强酶的活性（提高 132.25%和 110.37%），而 0.05%的 SDS 则会抑制酶的活性（降低 14.07%）。葡聚糖酶处理后，变异链球菌和混合种口腔生物膜的厚度分别从 54,340nm 减少到 36,670nm 和从 64,260nm 减少到 43,320nm。
