Direct affinity immobilization of recombinant heparinase I fused to maltose binding protein on maltose-coated magnetic nanoparticles

作者：Wu, Jingjun; Zhou, Lilin; Zhang, Huijuan; Guo, Jun; Mei, Xiang; Zhang, Chong; Yuan, Jinying; Xing, Xin-Hui^*

来源：Biochemical Engineering Journal, 2014, 90: 170-177.

DOI：10.1016/j.bej.2014.05.021

• Affinity
• Adsorption
• Heparinase I
• Immobilization
• Magnetic nanoparticles
• Enzyme biocatalysis

Hybrid magnetic Fe3O4@SiO2-Poly(ethylene oxide)-maltose (Fe3O4@SiO2-PEO-mal) nanoparticles synthesized by our group can be used as affinity adsorption carriers for direct separation of maltose binding protein-fused Hep I (MBP-Hep I) from a crude enzyme solution in a magnetic field. In this work, different PEO molecular weights for Fe3O4@SiO2-PEO-mal nanoparticles were used for characterizing of MBP-Hep I immobilization. The results showed that all four kinds of Fe3O4@SiO2-PEO-mal magnetic nanoparticles (6k, 20k, 35k and 100k for PEO) exhibited excellent adsorption capacities and the adsorption ratio increased as the PEO molecular weight increased from 6k to 100k. All four kinds of immobilized MBP-Hep I exhibited significantly improved stability at 30 degrees C compared with free MBP-Hep I and their half-lives were 20-50 times that of the free MBP-Hep I. Fe3O4@SiO2-PEO-mal nanoparticles with a PEO molecular weight of 100k were best able to immobilize MBP-Hep I (Fe3O4@SiO2-PEO100k-mal-MBP-Hep I). The molecular weight distribution profiles and anticoagulant activities, obtained from heparin depolymerization by free Hep I, free MBP-Hep land Fe3O4@SiO2-PEO100k-mal-MBP-Hep I were the same. Furthermore, Fe3O4@SiO2-PEO100k-mal-MBP-Hep I exhibited reasonable reusability during enzymatic production of low molecular weight heparins (LMWHs).

• 出版日期2014-9-15
• 单位清华大学