%0 Journal Article %T 海洋来源褐藻胶裂解酶分离纯化及酶学性质研究<br>Purification and characterization of the alginate lyase isolated from marine %A 韩 %A 伟 %A 许鑫琦 %A 叶秀云 %A 林 %A 娟 %J 福州大学学报(自然科学版) %D 2018 %R 10.7631/issn.1000-2243.16334 %X 以假交替单胞菌(Pseudoalteromonas sp. zb7-4)发酵制备褐藻胶裂解酶粗酶液,采用弱阴离子DEAE交换层析分离褐藻胶裂解酶,分析纯化褐藻胶裂解酶AlgL的酶学特性. 结果表明:AlgL的表观分子质量约为32ku,比活力为(208.26±5.87)U·mg-1;其最适反应pH为7.0,在pH为6.0~10.0范围内稳定性较好,保温1h仍能保持80%以上的相对酶活力;最适反应温度50℃,在40℃保温30min,其残余酶活力高于80%;Cu2+、Cr3+、Co2+、Ba2+、Sr2+、Hg2+对该酶具有不同程度的抑制作用,Hg2+抑制作用最为明显;该酶具有较好的盐耐受性,在3mol·L-1 NaCl反应体系中保温2h,仍残余66%酶活力. 动力学参数Km、Vmax、Kcat测定表明,该酶对聚古罗糖醛酸钠(PG)亲和力较高,为偏好聚甘露糖醛酸钠(PM)裂解作用的双功能酶.<br>Alginate lyase AlgL was successfully purified from fermented broth of Pseudoalteromonas sp. zb7-4 by DEAE weak anion exchange chromatography and the enzymatic properties of alginate lyase were characterized. The results showed that the purified alginate lyase was a monomer with apparent molecular weight of approximately 32ku and specific activity of (208.26±5.87)U·mg-1. The optimum pH for enzyme was 7.0,it was stable in the pH range of 6.0 to 10.0,and its relative enzyme activity could still maintain more than 80% after 1 h’s incubation. The optimum temperature for enzyme was 50℃,and its residual enzyme activity was still 80% after 30 min’s incubation at 40℃. Cu2+,Cr3+,Co2+,Ba2+,Sr2+,Hg2+ showed inhibitory effects on the enzyme activity while Hg2+ was the most obvious. The enzyme had a good ability of salt tolerance,and its relative enzyme activity retained more than 66% after 2 h’s incubation in 3mol·L-1 NaCl. The values of Km、Vmax、Kcat showed that the enzyme was a bifunctional enzyme which prefered sodium polymannuronate (Poly M) %K 褐藻胶裂解酶 假交替单胞菌 纯化 酶学性质< %K br> %K alginate lyase Pseudoalteromonas sp. purification enzymatic property %U http://xbzrb.fzu.edu.cn/ch/reader/view_abstract.aspx?file_no=201801022&flag=1