摘要
利用静电层层自组装方法对漆酶进行固定化,在固体基底(云母片)上制备了阳离子聚丙烯酰胺(CPAM)/漆酶自组装膜;通过紫外可见吸收光谱、原子力显微镜对自组装膜的活力增长情况及表面形貌进行分析表征,并对层层自组装方法固定化漆酶的酶学性质进行了研究.结果表明:CPAM/漆酶自组装膜的活力随着自组装层数的增多呈线性增长,通过改变吸附周期可以有效地控制吸附在基底上的酶量;漆酶在自组装膜中排列有序,自组装膜的平均高度及均方根粗糙度随着自组装层数的增大逐渐增大;固定化漆酶最适pH值为5.0,最适温度为50℃,比游离漆酶高5℃,固定化漆酶对ABTS的米氏常数为0.042 mmol/L,与游离漆酶相比,该固定化漆酶热稳定性明显提高;固定化漆酶具有良好的可重复使用性和存储稳定性.
Laccase was immobilized through the electrostatic layer-by-layer self-assembly, and cationic polyacrylamide （CPAM） /laccase self-assembled films were prepared on solid substrate （mica）. Then, the activities and morphologies of the films were characterized by means of the UV-Vis spectroscopy and the atomic force microscopy, and the enzymatic properties of the immobilized laccase were also analyzed. The results show that the activity of the CPAM/laccase self-assembled film linearly increases with the number of layers, and the enzyme loading can be effectively controlled by changing the adsorption cycles, and that the laccase molecules are arranged orderly in the films, and the average height and RMS roughness of the self-assembled film increase with the number of layers. Moreover, it is found that the optimal pH value and temperature of the immobilized laccase are respectively 5.0 and 50 ℃, which is 5 ℃ higher than that of free laccase, and the corresponding Michaelis constant for ABTS is 0. 042 mmol/L, that the thermal stabilities of the immobilized laccase is significantly higher than those of free laccase, and that the immobilized laccase is of excellent reusability and high storage stability.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第9期158-164,共7页
Journal of South China University of Technology(Natural Science Edition)
基金
国家"973"计划项目(2010BC732206)
国家自然科学基金资助项目(30771689
30972324)
教育部高校博士点基金资助项目(20090172110022)
关键词
漆酶
层层自组装
固定化
热稳定性
存储稳定性
laccase
layer-by-layer self-assembly
immobilization
thermal stability
storage stability
