Immobilization of O-acetylserine sulfhydrylase as a highly active and recyclable nanobiocatalyst: efficient synthesis of β-pyrazol-1-yl-l-alanine

2016 ◽  
Vol 6 (16) ◽  
pp. 6286-6293 ◽  
Author(s):  
Akbar K. Vahidi ◽  
Zunsheng Wang ◽  
William S. Y. Wong ◽  
Zhi Li

O-Acetylserine sulfhydrylase (OASS) is immobilized directly from CFE containing His-tagged OASS with magnetic nanoparticles Ni-NTA-MNPs via affinity attachment. The immobilized enzyme shows full free-enzyme activity and excellent recyclability and produces 1080 mM β-pyrazol-1-yl-alanine in 20 reaction cycles.

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3188 ◽  
Author(s):  
Fouzia Hussain ◽  
Sara Arana-Peña ◽  
Roberto Morellon-Sterling ◽  
Oveimar Barbosa ◽  
Sabrina Ait Braham ◽  
...  

Alcalase was immobilized on glyoxyl 4% CL agarose beads. This permitted to have Alcalase preparations with 50% activity retention versus Boc-l-alanine 4-nitrophenyl ester. However, the recovered activity versus casein was under 20% at 50 °C, as it may be expected from the most likely area of the protein involved in the immobilization. The situation was different at 60 °C, where the activities of immobilized and free enzyme became similar. The chemical amination of the immobilized enzyme or the treatment of the enzyme with glutaraldehyde did not produce any significant stabilization (a factor of 2) with high costs in terms of activity. However, the modification with glutaraldehyde of the previously aminated enzyme permitted to give a jump in Alcalase stability (e.g., with most than 80% of enzyme activity retention for the modified enzyme and less than 30% for the just immobilized enzyme in stress inactivation at pH 7 or 9). This preparation could be used in the hydrolysis of casein at pH 9 even at 67 °C, retaining around 50% of the activity after 5 hydrolytic cycles when the just immobilized preparation was almost inactive after 3 cycles. The modified enzyme can be reused in hydrolysis of casein at 45 °C and pH 9 for 6 cycles (6 h) without any decrease in enzyme activity.


2012 ◽  
Vol 14 (4) ◽  
pp. 57-60
Author(s):  
Peng Zhang ◽  
Chunli Liu ◽  
Shanshan Song ◽  
Chifang Peng

Abstract A novel method of immobilizing horse radish peroxidase enzyme (HRP) onto the surface of gold nanoparticles (GNPs) was developed. As a result, a high-activity bionanoconjugates was obtained through utilizing the biotin-streptavidin (SA) system. The HRP-SA-GNP bionanoconjugate with high activity was conveniently prepared through the biotin- avidin system. Compared with the HRP-GNP bioconjugate prepared through the traditional electrostatic absorption method, the enzyme activity per GNPs of this new bionanoconjugate was enhanced by 10 times. Moreover, the enzyme activity of this bionanoconjugate was controllable. The above method of bionanoconjugation preparation has promising applications in the fields including preparing highly active bio-nanoprobe and immobilized enzyme.


2019 ◽  
Vol 20 (1) ◽  
pp. 12-23
Author(s):  
Maan Alkhatib ◽  
Nik Adlin Bahrudin ◽  
HAMZAH M. SALLEH ◽  
Mohamed M. E. Nasef ◽  
Teo M. Ting

ABSTRACT: Lipase enzyme originated from wheat germ was immobilized on nylon -6- grafted with polyglycidyl methachrylate (PGMA). The immobilization of enzyme experiments were designed and studied using face centred central composite design (FCCCD) under response surface methodology (RSM). Prior to immobilization, the polymer was activated with diethyl amine/ethanol to introduce an amine functional group to facilitate covalent bonding with the enzyme. The immobilized and free enzymes were characterized for effect of temperature and pH on enzyme activity, stability, storage and reusability as well as kinetics studies. ANOVA revealed that optimum lipase activity of 0.287 U/ml was achieved at immobilization time of 5 h, pH of 6 and 1.0 mg/ml for enzyme concentration. The optimum temperatures and pH for immobilized and free enzymes were 45 °C and 35 °C, and 8 and 7, respectively. The immobilized enzyme showed higher stability compared to free enzyme. The immobilized enzyme retained 18% of its activity after being recycled 8 times. In a storage stability test, immobilized lipase was able to retain 70% of its activity after being stored for 30 days, while free enzyme activity dropped to 15 % after 20 days of storage. ABSTRAK:Enzim Lipase telah dihasilkan daripada mikroorganisma pegun gandum di atas nilon -6- dan digraf bersama poliglisidel methakrilet (PGMA). Enzim pegun ini direka dan dikaji secara eksperimen menggunakan reka bentuk campuran pusat pada permukaan (FCCCD) di bawah kaedah tindak balas permukaan (RSM). Sebelum menjadi pegun, polimer ini telah diaktifkan dengan dietil amine/ethanol bagi menghasilkan kumpulan fungsi amine bagi membantu ikatan kovalen atom pada enzim. Enzim pegun dan bebas ini telah dikategorikan mengikut kesan enzim ke atas suhu, aktiviti enzim ke atas kesan pH, kestabilan, keboleh-simpanan dan keboleh-gunaan balik, serta ujian tindak balas kinetik. ANOVA membuktikan bahawa aktiviti optimum enzim lipase ini adalah sebanyak 0.287 U/ml telah terhasil selama 5 jam pegun, pada pH 6 dan kepekatan enzim sebanyak 1.0 mg/ml. Suhu dan pH optimum, pada enzim pegun dan enzim bebas ini adalah pada 45 °C dan 35 °C, dan pH 8 dan 7, masing-masing. Enzim pegun ini menunjukkan lebih stabil daripada enzim bebas. Enzim pegun dilihat kekal 18% daripada aktivitinya selepas 8 kali ulangan. Melalui ujian kestabilan simpanan, enzim lipase pegun dapat mengekalkan 70% daripada aktivinya selepas disimpan selama 30 hari, manakala aktiviti enzim bebas telah menurun kepada 15% selepas 20 hari dalam simpanan.


2011 ◽  
Vol 183-185 ◽  
pp. 2063-2067
Author(s):  
Qing Qi Guo ◽  
Na Zhang ◽  
Gui Zhen Fang

Dialdehyde oxycellulose-coated magnetite nanoparticles were prepared as carrier to immobilize the lactase, the preparation conditions and enzymatic properties of the immobilized enzyme were studied. The results showed that the maximum activity of immobilized enzyme is 0.424U/g when immobilized time is 4h, immobilized pH is 6.5, [enzyme]/[carrier] =1:15(g:g). Compared with free enzyme, the heat stability and basic resistance of immobilized lactase were increased. After reuse five times, the relative enzyme activity of immobilized enzyme was 63%.


2019 ◽  
Vol 15 (3) ◽  
pp. 296-303 ◽  
Author(s):  
Swapnil Gaikwad ◽  
Avinash P. Ingle ◽  
Silvio Silverio da Silva ◽  
Mahendra Rai

Background: Enzymatic hydrolysis of cellulose is an expensive approach due to the high cost of an enzyme involved in the process. The goal of the current study was to apply magnetic nanomaterials as a support for immobilization of enzyme, which helps in the repeated use of immobilized enzyme for hydrolysis to make the process cost-effective. In addition, it will also provide stability to enzyme and increase its catalytic activity. Objective: The main aim of the present study is to immobilize cellulase enzyme on Magnetic Nanoparticles (MNPs) in order to enable the enzyme to be re-used for clean sugar production from cellulose. Methods: MNPs were synthesized using chemical precipitation methods and characterized by different techniques. Further, cellulase enzyme was immobilized on MNPs and efficacy of free and immobilized cellulase for hydrolysis of cellulose was evaluated. Results: Enzymatic hydrolysis of cellulose by immobilized enzyme showed enhanced catalytic activity after 48 hours compared to free enzyme. In first cycle of hydrolysis, immobilized enzyme hydrolyzed the cellulose and produced 19.5 ± 0.15 gm/L of glucose after 48 hours. On the contrary, free enzyme produced only 13.7 ± 0.25 gm/L of glucose in 48 hours. Immobilized enzyme maintained its stability and produced 6.15 ± 0.15 and 3.03 ± 0.25 gm/L of glucose in second and third cycle, respectively after 48 hours. Conclusion: This study will be very useful for sugar production because of enzyme binding efficiency and admirable reusability of immobilized enzyme, which leads to the significant increase in production of sugar from cellulosic materials.


RSC Advances ◽  
2021 ◽  
Vol 11 (17) ◽  
pp. 10010-10017
Author(s):  
Ping-Chung Kuo ◽  
Zhi-Xun Lin ◽  
Tzi-Yi Wu ◽  
Chun-Han Hsu ◽  
Hong-Ping Lin ◽  
...  

Mesoporous silica films were used as supports with high loading capacity and enzyme activity.


2019 ◽  
Vol 43 (23) ◽  
pp. 8930-8938 ◽  
Author(s):  
Zahra Tashrifi ◽  
Saeed Bahadorikhalili ◽  
Hossein Lijan ◽  
Samira Ansari ◽  
Haleh Hamedifar ◽  
...  

A novel catalyst is synthesized based on the immobilization of palladium on γ-Fe2O3@SiO2–(CH2)3–PDTC nanoparticles and is used as a highly active catalyst for the Heck/Sonogashira coupling reactions.


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