β-半乳糖苷酶磁性交联酶聚体的制备及性质研究  

The Preparation and Properties of Magnetic Cross-linked β-Galactosidase Aggregates

作　　者：孙槐胜 邢肖肖[1,3] 齐崴[1,2,4] 王梦凡[1,4] 邢肖肖[1,3] 苏荣欣[1,2,4] 何志敏 

机构地区：[1]天津大学化工学院,天津300072 [2]天津大学化学工程联合国家重点实验室,天津300072 [3]天津大学理学院,天津300072 [4]天津市膜科学与海水淡化技术重点实验室,天津300072

出　　处：《南开大学学报（自然科学版）》2016年第3期18-24,共7页Acta Scientiarum Naturalium Universitatis Nankaiensis

基　　金：国家自然科学基金(21206113,20976125);天津市自然科学基金(13JCQNJC09300)

摘　　要：制备了β-半乳糖苷酶磁性交联酶聚体,优化了制备条件,并对其酶学性质进行了系统研究.实验结果表明,最优的制备条件为,4.2 mg Fe3O4磁性纳米颗粒,20 mg/m L的BSA 2m L,吸附时间为1.5 h,β-半乳糖苷酶酶液50μL,沉淀剂为异丙醇,体积比为1∶1,沉淀时间1h,戊二醛体积分数为0.125%,交联时间1 h,在此条件下得到的β-半乳糖苷酶M-CLEAs酶活保留率为58.67%.扫描电镜观察显示β-半乳糖苷酶磁性交联酶聚体呈多孔结构,比表面积大.与游离酶相比,β-半乳糖苷酶M-CLEAs具有更加宽泛的催化温度和p H范围,同时表现出较好的重复利用性.The magnetic cross-linked β-galactosidaseaggregates（M-CLEAs） were prepared. The programs and conditions were optimized and the enzymatic properies of β-galactosidase M-CLEAs were also studied. The optimal conditions for preparation of β-galactosidase M-CLEAs were determined as follows：100 μL 0.042 g/m L Fe3O4 magnetic nanoparticle and 2 m L 20 mg/m L BSA were mixed and stirred for1.5 h; 20 times dilution of original enzyme liquid, 1∶1 of 2-propanol（v/v） precipitation for 60 min at4 ℃, and cross-linking of 60 min by 0.125 %（v/v） glutaraldehyde. Thus 58.67% of the reservation activity could be otained. It was observed that the β-galactosidase M-CLEAs were irregular polyhedron structure which had a large specific surface area. The β-galactosidase M-CLEAs showed improved thermal stability and p H stability compared with the free β- galactosidase. Furthermore, the β- galactosidase MCLEAs also exhibited better operational stability than that of the free β-galactosidase.

关 键 词：Β-半乳糖苷酶 固定化 磁性交联酶聚体 

分 类 号：Q814.2[生物学—生物工程]