Based on DNA Strand Displacement and Functionalized Magnetic Nanoparticles: A Promising Strategy for Enzyme Immobilization

作者：Song, Jiayi; Su, Ping^*; Ma, Ruian; Yang, Ye; Yang, Yi

来源：Industrial & Engineering Chemistry Research, 2017, 56(17): 5127-5137.

DOI：10.1021/acs.iecr.7b00595

• EFFICIENT PROTEIN DIGESTION
• ON-PLATE DIGESTION
• GRAPHENE OXIDE
• DIRECTED IMMOBILIZATION
• ALKALINE-PHOSPHATASE
• SILICA NANOPARTICLES
• INHIBITION ASSAYS
• GLUCOSE-OXIDASE
• TRYPSIN
• STABILITY

The efforts to enhance the stability of enzymes and improve their activity have generated considerable interest because of their wide applications in bioenergy conversion, proteomics research, and bioassays. This study reports a promising strategy for enzyme immobilization based on toehold-mediated DNA strand displacement on functionalized magnetic nanoparticles for the first time. The strategy provided a convenient approach to achieve sequential displacement and immobilization of different enzymes, using alkaline phosphatase (ALP), horseradish peroxidase (HRP), and trypsin as different model enzymes. Taking trypsin as an example, the enzyme immobilization procedure by DNA strand displacement exhibited high reversibility and reproducibility, which could retrieve more than 87% of the enzymatic activity after consecutive hybridization and dehybridization cycles. The thermal stability of the immobilized trypsin was significantly enhanced up to 3.1- and 2.3-fold greater than free enzyme after 45 min incubation at 60 and 70 degrees C, respectively, and the immobilized enzyme preserved promising enzymatic activity of than 87% after 10 cycles. Notably, the immobilized enzyme exhibited excellent long-term incubation stability and storage stability as compared with free enzyme and showed up: to 11-fold higher-stability than free enzyme toward different solvents. Significantly improved digestion efficiency of myoglobin, glycated hemoglobin, and cytochrome C achieved with this immobilized enzyme within 10 min, and the obtained sequence coverages were 1.5-, 1.3-, and 1.6-fold higher than conventional in-solution digestion for 12 h. Thus the developed strategy exhibited a promising alternative platform with high magnetic responsiveness and significantly enhanced, properties for the immobilization of important enzymes and their broad applications.

• 出版日期2017-5-3
• 单位北京化工大学