TY  - JOUR
TI  - Different spacer-arm attached magnetic nanoparticles for covalent immobilization of Jack bean urease
AB  - Objectives: This study aims the covalent immobilization of Jack bean urease on Fe3O4 magnetic nanoparticles via glutaraldehyde (urease@MNPs-Si-Glu) and epichlo- rohydrin (urease@MNPs-ECH) spacer arms. Methods: The optimum pH and temperature, thermal, storage and reuse stability of free and immobilized urease preparations were investigated. Thermodynamics cha- racterizations of free and immobilized urease preparations were also studied. Results: The free urease and both immobilized urease pre- parations showed maximal catalytic activity at pH 7.5. The free urease had a maximal catalytic activity at 50 °C, while the both immobilized urease preparations exhibited their maxi- mal catalytic activities at 70 °C. The urease@MNPs-Si-Glu and urease@MNP-ECH showed 2.7- and 1.9-fold higher thermal stability than the free urease at 60 °C, respectively. The free urease remained 30% of their initial activity at 4 °C, while urease@MNPs-Si-Glu and urease@MNPs-ECH retained 72 and 60% of their initial activities at the same conditions. The urease@MNPs-Si-Glu and urease@MNPs-ECH preserved 53 and 52% of their initial activities, respectively for urea hydrolysis after 20 reuses. Conclusions: The urease@MNPs-Si-Glu and urease@MNPs- ECH may find a potential application area in urea hydrolysis.
AU  - Yildirim, Deniz
AU  - GÜLESCI, NURI
AU  - YÜCEBILGIÇ, GÜZIDE
DO  - 10.1515/tjb-2021-0264
PY  - 2022
JO  - Türk Biyokimya Dergisi
VL  - 47
IS  - 4
SN  - 1303-829X
SP  - 501
EP  - 509
DB  - TRDizin
UR  - http://search/yayin/detay/1176444
ER  -