Synergistic precipitant powered self-assembly of papain for cross-linked enzyme crystals preparation  

作　　者：Qi Hao Pan Guo Honghai Wang Min Su Chunli Li Yuqi Hu Weiyi Su 

机构地区：[1]School of Chemical Engineering and Technology,Hebei University of Technology,Tianjin,300130,China [2]National-Local Joint Engineering Laboratory for Energy Conservation of Chemical Process Integration and Resources Utilization,Tianjin,300130,China

出　　处：《Particuology》2024年第2期102-112,共11页颗粒学报（英文版）

基　　金：supported by the Natural Science Foundation of Hebei Province(grant Nos.B2020202015,B2020202066);National Natural Science Foundation of China(grant Nos.21878066,22008050).

摘　　要：In this study,we prepared cross-linked enzyme crystals(CLECs)of papain to further broaden the application of the enzyme with high activity in extreme environments.Initially,papain crystals were successfully obtained based on the micro-batch,batch,and expanded batch crystallization experiments.Specifically,ammonium sulfate and polyethylene glycol 6000(PEG6000)were synergistically used as the precipitants,while L-cysteine was applied to enhance the activity of papain.Furthermore,the interaction between L-cysteine and papain was modeled by molecular docking technique.It was found that L-cysteine could form a hydrogen bond with aspartic acid residue(Asp)at site 158,and the electrostatic attraction with lysine residue(Lys)at site 156 was also quite obvious.Then the enzyme crystals were cross-linked by glutaraldehyde at optimized conditions.The papain CLECs were identified by various methods,and it was found that the thermal stability and enzymatic activity both increased compared to the raw enzyme.More importantly,it could be applied at more rigorous conditions,for example,pH of 4.

关 键 词：PAPAIN Cross-linked enzyme crystals L-CYSTEINE Molecular docking Crystallization 

分 类 号：Q946.5[生物学—植物学]