Wang Le, Sun Pengxue, Yang Yiyu, Qiao Hanzhen, Tian Hailong, Wu Dapeng, Yang Shuoye, Yuan Qipeng, Wang Jinshui
College of Biological Engineering, National Engineering Laboratory for Wheat & Corn Further Processing, Henan University of Technology, Zhengzhou 450001, China.
School of Environment, Henan Normal University, Xinxiang 453001, China.
Nanomaterials (Basel). 2021 Aug 25;11(9):2171. doi: 10.3390/nano11092171.
The field of enzyme cascades in limited microscale or nanoscale environments has undergone a quick growth and attracted increasing interests in the field of rapid development of systems chemistry. In this study, alcohol dehydrogenase (ADH), lactate dehydrogenase (LDH), and mesoporous silica nanoparticles (MSN) immobilized nicotinamide adenine dinucleotide (NAD) were successfully immobilized on the zeolitic imidazolate frameworks (ZIFs). This immobilized product was named ZIF@ADH/NAD-MSN/LDH, and the effect of the multi-enzyme cascade was studied by measuring the catalytic synthesis of lactic acid. The loading efficiency of the enzyme in the in-situ co-immobilization method reached 92.65%. The synthesis rate of lactic acid was increased to 70.10%, which was about 2.82 times that of the free enzyme under the optimal conditions (40 °C, pH = 8). Additionally, ZIF@ADH/NAD-MSN/LDH had experimental stability (71.67% relative activity after four experiments) and storage stability (93.45% relative activity after three weeks of storage at 4 °C; 76.89% relative activity after incubation in acetonitrile-aqueous solution for 1 h; 27.42% relative activity after incubation in 15% N, N-Dimethylformamide (DMF) solution for 1 h). In summary, in this paper, the cyclic regeneration of coenzymes was achieved, and the reaction efficiency of the multi-enzyme biocatalytic cascade was improved due to the reduction of substrate diffusion.
在有限的微尺度或纳尺度环境中的酶级联反应领域发展迅速，在系统化学快速发展领域引起了越来越多的关注。在本研究中，乙醇脱氢酶（ADH）、乳酸脱氢酶（LDH）和固定化烟酰胺腺嘌呤二核苷酸（NAD）的介孔二氧化硅纳米颗粒（MSN）成功固定在沸石咪唑酯骨架（ZIFs）上。这种固定化产物被命名为ZIF@ADH/NAD-MSN/LDH，并通过测量乳酸的催化合成来研究多酶级联反应的效果。原位共固定化方法中酶的负载效率达到92.65%。在最佳条件（40℃，pH = 8）下，乳酸的合成速率提高到70.10%，约为游离酶的2.82倍。此外，ZIF@ADH/NAD-MSN/LDH具有实验稳定性（四次实验后相对活性为71.67%）和储存稳定性（在4℃储存三周后相对活性为93.45%；在乙腈-水溶液中孵育1小时后相对活性为76.89%；在15% N，N-二甲基甲酰胺（DMF）溶液中孵育1小时后相对活性为27.42%）。总之，本文实现了辅酶的循环再生，并且由于底物扩散的减少提高了多酶生物催化级联反应的效率。
