Department of Pharmacy, Danyang People's Hospital, Danyang 212300, P.R. China.
School of Pharmacy, Jiangsu University, Zhenjiang 212013, P.R. China.
J Microbiol Biotechnol. 2019 Jun 28;29(6):913-922. doi: 10.4014/jmb.1903.03017.
Magnetic NiCoFeO nanoparticles that were prepared via the rapid combustion process were functionalized and modified to obtain magnetic NiCoFeO@SiO-CHO nanocomposites, on which penicillin G acylase (PGA) was covalently immobilized. Selections of immobilization concentration and time of fixation were explored. Catalytic performance of immobilized PGA was characterized. The free PGA had greatest activity at pH 8.0 and 45oC while immobilized PGA's a ctivities peaked a t pH 7.5 and 45°C. Immobilized PGA had better thermal stability than free PGA at the range of 30-50°C for different time intervals. The activity of free PGA would be 0 and that of immobilized PGA still retained some activities at 60°C after 2 h. and of immobilized PGA were 1.55 mol/min and 0.15 mol/l, respectively. Free PGA's and separately were 0.74 mol/min and 0.028 mol/l. Immobilized PGA displayed more than 50% activity after 10 successive cycles. We concluded that immobilized PGA with magnetic NiCoFeO@SiO-CHO nanocomposites could become a novel example for the immobilization of other amidohydrolases.
通过快速燃烧法制备的磁性 NiCoFeO 纳米粒子经功能化和修饰后得到磁性 NiCoFeO@SiO-CHO 纳米复合材料，其上共价固定有青霉素 G 酰化酶（PGA）。研究了固定化浓度和固定时间的选择。对固定化 PGA 的催化性能进行了表征。游离 PGA 在 pH8.0 和 45°C 时活性最大，而固定化 PGA 的活性在 pH7.5 和 45°C 时达到峰值。在 30-50°C 的不同时间间隔内，固定化 PGA 的热稳定性优于游离 PGA。游离 PGA 在 2 h 后于 60°C 时活性降为 0，而固定化 PGA 仍保留部分活性。固定化 PGA 的 和 分别为 1.55 mol/min 和 0.15 mol/L，游离 PGA 的 和 分别为 0.74 mol/min 和 0.028 mol/L。固定化 PGA 在 10 次连续循环后仍保留超过 50%的活性。我们得出结论，磁性 NiCoFeO@SiO-CHO 纳米复合材料固定化 PGA 可为其他酰胺水解酶的固定化提供新的范例。
