INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Xing Zhu,Yuanyuan Qiang,Xuechuan Wang,Mingliang Fan,Zuoyuan Lv,Yi Zhou,Bin He
Immobilized enzymes are one of the most common tools used in enzyme engineering, as they can substantially reduce the cost of enzyme isolation and use. However, efficient catalysis of solid substrates using immobilized enzymes is challenging, hydrolysis of insoluble cellulose by immobilized cellulases is a typical example of this problem. In this study, inspired by bees and honeycombs, we prepared gelatin-modified cellulase (BEE) and gelatin hydrogels (HONEYCOMB) to achieve reversible recycling versus release of cellulase through temperature-responsive changes in the triple-stranded helix-like interactions between BEE and HONEYCOMB. At elevated temperatures, BEE was released from HONEYCOMB and participated in hydrolytic saccharification . After 24 h, the glucose yields of both the free enzyme and BEE reached the same level. When the temperature was decreased, BEE recombined with HONEYCOMB to facilitate the effective separation and recycling of BEE from the system. The enzymatic system retained >70 % activity after four reuse cycles. In addition, this system showed good biocompatibility and environmental safety. This method increases the mass transfer capacity and enables easy recovery of immobilized cellulase, thereby serving as a valuable strategy for the immobilization of other enzymes.
研究领域:
生物化学
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酶工程
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DOI
PubMed
高影响因子
Energy & Environmental Materials
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2020
·Vol. 3
·期 4
·535-540
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IF 0
Yang-Peng Lin,Bing Xia,Sanlue Hu,Yu Zhong,Yue-E Huang,Zhi-Zhuan Zhang,Ni Wu,Yong-Wei Wu,Xiao-Hui Wu,Xiao-Ying Huang,Zewen Xiao,Ke-Zhao Du
Bromine is an irreplaceable reagent for many important applications including necessary additive for flame retardants and rubber treatment. However, the toxicity, causticity, and vaporability of bromine make the safe usage and transportation of bromine challenging, which can be alleviated by the bromine prefixation. Herein, vacancy-ordered bromide perovskites such as Cs 4 Sb 2 Br 12 and Cs 2 PdBr 6 are selected out for the bromine fixation through density-functional theory calculations and experiments. The redox within the bromide perovskites is designed to provide the driving force for the reversible release and fixation of bromine. Heating and cooling the title bromide perovskites in a necked ampoule make the bromine visible and separable from the solid residue. The composition engineering ( i.e. , Cs 4 Sb 2 Br 12 vs Rb 4 Sb 2 Br 12 , and Cs 4 Sb 2 Br 12 vs Cs 2 PdBr 6 ) can effectively tune the stability (against water and high temperature) and the bromine storage capacity (from 9.30% to 18.76%). In addition, this work can provide a one-step preparation method for the liquid bromine without further purification.
研究领域:
材料科学
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化学
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DOI
Microfluidics and Nanofluidics
·
2014
·Vol. 17
·期 4
·721-728
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IF 2.665
Tang Xiuwen,Liu Sufang,Wang Sifeng,Zhang Qin,Cheng Zhiyi
We have developed a sensitive enzyme inhibition assay on microfluidic system. The analysis was carried out by immobilizing enzyme through amide-bond or disulfide-bond formation with surface. Followed by detection of reaction product through fluorescent density were evaluated reusability, stability and sensitivity of microfluidic enzyme assay. The Michaelis–Menten parameters for free urease ( K
M = 1.027 μM) and for immobilized urease ( K
M = 1.528 μM of disulfide-bond immobilization; K
M ′ = 1.617 μM of amide-bond immobilization) showed reasonable activities maintained after immobilization with relative standard deviation (RSD) of 4.86 and 6.06 %, respectively. When compared enzyme activities of five repeated immobilization cycles through reversible disulfide-bond immobilization, we found that removal process and reversible immobilization did not affect efficiency of microreactor with RSD of 4.78 %. The IC 50 value 368 μM of inhibitor acetohydroxamic acid determined on chip showed good agreement with reported data 375 μM; K
i of 1.39 μM matched well with K
i of 1.46 μM via the traditional 96-microplate. This microfluidic could be extended to screening of enzyme inhibitor and enzymatic reaction kinetics study, which may be useful for clinical diagnostics, biotechnological research, drug discovery and other bioassays.
研究领域:
生物化学
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药物开发
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临床诊断
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DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
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2014
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IF 2.745
Bingbing Li,Yong Chen,Zhi Cao,Huanqing Niu,Dong Liu,Ying He,Xiaochun Chen,Jinglan Wu,Jingjing Xie,Wei Zhuang,Hanjie Ying
The reversible immobilization of crude nuclease P 1 fermented by Penicllium citrinum and used without further purification was performed via adsorption on a weak base anion resin activated by polyethylenimine (PEI). The immobilization conditions, including PEI concentration, the amount of support, the immobilization time, and the reusability of the PEI-activated resin were investigated. The results have shown that the PEI-activated resin has the capability of selectively adsorbing nuclease P 1 . Subsequently, the functional properties of the immobilized nuclease P 1 were studied and compared to those of the free enzyme. The apparent K m value for immobilized nuclease P 1 on the activated resin (15.31 g L −1 ) was about 4.41-fold higher than that of the free enzyme (3.47 g L −1 ), and the apparent V max value of the immobilized enzyme (530 U g −1 ) was about 3.9-fold less than that of the free enzyme (2082 U mL −1 ). The optimum temperature was observed to be 70 °C, 15 °C higher than that of the free enzyme. The optimum pH was the same for both free and immobilized nuclease P 1 (pH 5.0). The apparent activation energies ( E a ) of the free and immobilized nuclease P 1 were 163.09 kJ mol −1 and 156.32 kJ mol −1 , respectively, implying that the catalytic efficiency of the immobilized enzyme was restricted by mass-transfer rather than kinetic limitations.
研究领域:
生物化学
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酶工程
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DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2021
·
IF 9.642
Chunyang Bao,Yan Wang,Xiaoling Xu,Die Li,Jing Chen,Zhangbin Guan,Bingyu Wang,Mei Hong,Jingyu Zhang,Tianheng Wang,Qiang Zhang
It is challenging to regenerate enzyme carriers when covalently immobilized enzymes suffered from inactivation during continuous operations. Hence, it is urgent to develop a facile strategy to immobilize enzymes reversibly. Herein, the non-covalent interaction between protein and carbohydrate was used to adsorb and desorb enzymes reversibly. Laccase was immobilized onto glycopolymer microspheres via protein-carbohydrate interaction using lectins as the intermediates. The enzyme loading and immobilization yield were up to 49 mg/g and 77.1% with highly expressed activity of 107.9 U/mg. The immobilized laccase exhibited enhanced pH stability and high activity in catalyzing the biodegradation of paracetamol. During ten successive recoveries, the immobilized laccases could be recycled while maintaining relatively high enzyme activity. The glycopolymer microspheres could be efficiently regenerated by elution with an aqueous solution of mannose or acid for further enzyme immobilization. This glycopolymer microspheres has excellent potential to act as reusable carriers for the non-covalent immobilization of different enzymes.
研究领域:
生物化学
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环境科学
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酶工程
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）