SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2020, Vol. 28 ›› Issue (8): 2173-2180.DOI: 10.1016/j.cjche.2020.01.014

• Biotechnology and Bioengineering • 上一篇    下一篇

Immobilization of urease in metal-organic frameworks via biomimetic mineralization and its application in urea degradation

Xiao Liang, Qing Li, Zhiyuan Shi, Shaowei Bai, Quanshun Li   

  1. Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China
  • 收稿日期:2019-10-18 修回日期:2020-01-20 出版日期:2020-08-28 发布日期:2020-09-19
  • 通讯作者: Quanshun Li
  • 基金资助:
    The authors gratefully acknowledge the supports from National Key R&D Program of China (2018YFC1105401), National Natural Science Foundation of China (81673502 and 81872928), Science & Technology Department of Jilin Province (20190201288JC), Education Department of Jilin Province (JJKH20190010KJ), Province-University Cooperation Project of Jilin Province (SXGJQY2017-4) and the Fundamental Research Funds of the Central Universities, China.

Immobilization of urease in metal-organic frameworks via biomimetic mineralization and its application in urea degradation

Xiao Liang, Qing Li, Zhiyuan Shi, Shaowei Bai, Quanshun Li   

  1. Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China
  • Received:2019-10-18 Revised:2020-01-20 Online:2020-08-28 Published:2020-09-19
  • Contact: Quanshun Li
  • Supported by:
    The authors gratefully acknowledge the supports from National Key R&D Program of China (2018YFC1105401), National Natural Science Foundation of China (81673502 and 81872928), Science & Technology Department of Jilin Province (20190201288JC), Education Department of Jilin Province (JJKH20190010KJ), Province-University Cooperation Project of Jilin Province (SXGJQY2017-4) and the Fundamental Research Funds of the Central Universities, China.

摘要: Enzyme immobilization has been accepted as an efficient technique for improving the stability and recyclability of enzymes. Herein, biomimetic mineralization strategy was employed to achieve the immobilization of urease in a type of metal-organic frameworks (zeolite imidazolate framework-8, ZIF-8), and the immobilized enzyme urease@ZIF-8 was systematically evaluated for its structure, activity, stability and recyclability, using the hydrolysis of urea as a model. The entrapment of urease was found to be realized in a synchronous manner with the formation of ZIF-8 crystal. The loading of urease in ZIF-8 was measured to be ca. 10.6% through the bicinchoninic acid (BCA) protein assay. The encapsulated urease could efficiently maintain its native conformation, which endowed the immobilized urease with excellent activity and stability, even in harsh conditions (e.g., in the presence of trypsin, acidic or alkali conditions, or at high temperature). Further, urease@ ZIF-8 exhibited good recyclability during the degradation of urea, in which it could keep 58.86% of initial activity after being used for 5 cycles. Thus, biomimetic mineralization could be potentially utilized as a promising method to prepare immobilized ureases with superior activity, stability and recyclability, thereby facilitating the construction of efficient catalysts for industrial biocatalysis and biosensing.

关键词: Urease, Metal-organic frameworks, Immobilization, Biomimetic mineralization, Stability, Recyclability

Abstract: Enzyme immobilization has been accepted as an efficient technique for improving the stability and recyclability of enzymes. Herein, biomimetic mineralization strategy was employed to achieve the immobilization of urease in a type of metal-organic frameworks (zeolite imidazolate framework-8, ZIF-8), and the immobilized enzyme urease@ZIF-8 was systematically evaluated for its structure, activity, stability and recyclability, using the hydrolysis of urea as a model. The entrapment of urease was found to be realized in a synchronous manner with the formation of ZIF-8 crystal. The loading of urease in ZIF-8 was measured to be ca. 10.6% through the bicinchoninic acid (BCA) protein assay. The encapsulated urease could efficiently maintain its native conformation, which endowed the immobilized urease with excellent activity and stability, even in harsh conditions (e.g., in the presence of trypsin, acidic or alkali conditions, or at high temperature). Further, urease@ ZIF-8 exhibited good recyclability during the degradation of urea, in which it could keep 58.86% of initial activity after being used for 5 cycles. Thus, biomimetic mineralization could be potentially utilized as a promising method to prepare immobilized ureases with superior activity, stability and recyclability, thereby facilitating the construction of efficient catalysts for industrial biocatalysis and biosensing.

Key words: Urease, Metal-organic frameworks, Immobilization, Biomimetic mineralization, Stability, Recyclability