Enhancement of Enzymatic Activity by Magnetic Spherical Polyelectrolyte Brushes: A Potential Recycling Strategy for Enzymes
writer：Xu, Yisheng; Wang, Siyi; Han, Haoya; Chen, Kaimin; Qin, Li; Xu, Jun; Wang, Jie; Li, Li; Guo, Xuhong
keywords：无
source：期刊
specific source：Langmuir, 2014, 30(37), 11156-11164
Issue time：2014年
Interactions between amyloglucosidase and magnetic spherical polyelectrolyte brushes (MSPB) were studied by turbidimetric titration, which reveals reversible and tunable behaviors of pH-dependent enzyme-SPB binding. Quantitative thermodyanmic parameters including binding affinity and stoichiometry between enzyme and SPBs were further measured by isothermal titration calorimetry (ITC). A large amount of enzyme can be loaded in MSPB without loss of MSPB stability. We demonstrated that the enzymatic activity of amyloglucosidase bound in MSPB could be greatly enhanced (catalytic reaction rate, kbound= 1.36kfree) compared to free enzyme acitivity in solution. This is tremendous improvement from other carrier systems that usually lead to a signi?cant decrease of enzymatic activity. Both the high enzyme loading capacity and the enhancement of the catalytic activity probably arise from the Coulombic interactions between the enzyme and MSPB. These ?ndings provide a practical strategy for enhancement of enzyme activity and enzyme recycling by MSPB.