scholarly journals The combination of covalent and ionic exchange immobilizations enables the coimmobilization on vinyl sulfone activated supports and the reuse of the most stable immobilized enzyme

2021 ◽  
Author(s):  
Sara Arana-Peña ◽  
Diego Carballares ◽  
Roberto Morellon-Sterling ◽  
Javier Rocha-Martin ◽  
Roberto Fernandez-Lafuente
Keyword(s):  
Immobilized Enzyme ◽  
Ionic Exchange ◽  
Vinyl Sulfone

scholarly journals Immobilization of the Peroxygenase from Agrocybe aegerita. The Effect of the Immobilization pH on the Features of an Ionically Exchanged Dimeric Peroxygenase

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 560
Author(s):  
Diego Carballares ◽  
Roberto Morellon-Sterling ◽  
Xiaomin Xu ◽  
Frank Hollmann ◽  
Roberto Fernandez-Lafuente
Keyword(s):  
Anion Exchange ◽  
Immobilized Enzyme ◽  
Residual Activity ◽  
Free Enzyme ◽  
The Other ◽  
Vinyl Sulfone ◽  
Agrocybe Aegerita ◽  
Inactive Form ◽  
The Stability

This paper outlines the immobilization of the recombinant dimeric unspecific peroxygenase from Agrocybe aegerita (rAaeUPO). The enzyme was quite stable (remaining unaltered its activity after 35 h at 47 °C and pH 7.0). Phosphate destabilized the enzyme, while glycerol stabilized it. The enzyme was not immobilized on glyoxyl-agarose supports, while it was immobilized albeit in inactive form on vinyl-sulfone-activated supports. rAaeUPO immobilization on glutaraldehyde pre-activated supports gave almost quantitative immobilization yield and retained some activity, but the biocatalyst was very unstable. Its immobilization via anion exchange on PEI supports also produced good immobilization yields, but the rAaeUPO stability dropped. However, using aminated agarose, the enzyme retained stability and activity. The stability of the immobilized enzyme strongly depended on the immobilization pH, being much less stable when rAaeUPO was adsorbed at pH 9.0 than when it was immobilized at pH 7.0 or pH 5.0 (residual activity was almost 0 for the former and 80% for the other preparations), presenting stability very similar to that of the free enzyme. This is a very clear example of how the immobilization pH greatly affects the final biocatalyst performance.

scholarly journals Immobilization of α - amylase from locale bacteria isolate Bacillus subtilis ITBCCB148 with diethylaminoethyl cellulose (DEAE-Cellulose)

2010 ◽  
Vol 7 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Yandri. Yandri ◽  
Tati Suhartati ◽  
Sutopo Hadipo Hadi
Keyword(s):  
Thermal Stability ◽  
Bacillus Subtilis ◽  
Immobilized Enzyme ◽  
Storage Temperature ◽  
Residual Activity ◽  
Deae Cellulose ◽  
Ionic Exchange ◽  
Optimum Temperature ◽  
Diethylaminoethyl Cellulose ◽  
Exchange Matrix

The thermal stability increase of a-amylase obtained from locale bacteria isolate Bacillus subtilis ITBCCB148 was achieved by immobilization process using an ionic exchange matrix of DEAE-Cellulose. The result showed that the immobilized enzyme has an optimum temperature of 60°C; KM 14.8 mL substrate and Vmax 42.4 U/mL. The thermal stability storage temperature of 60°C, pH 9.0 and 60 minutes demonstrated the immobilized enzyme has residual activity of 28.1%; ki = 0.0224 min.-1; and ΔGi = 103.7 kJ mol-1. Although the immobilized enzyme’s thermal stability was only increased 1.5 times, at higher temperatures, it was much more stable than the native enzyme.

On the Preparation of Bovine α-Thrombin

1978 ◽  
Vol 39 (01) ◽  
pp. 193-200 ◽  
Author(s):  
Erwin F Workman ◽  
Roger L Lundblad
Keyword(s):  
Immobilized Enzyme ◽  
Catalytic Properties ◽  
Specific Activity ◽  
Guanidine Hydrochloride ◽  
Low Molecular Weight ◽  
Reversible Process ◽  
Gel Beads ◽  
Tissue Thromboplastin ◽  
C 50 ◽  
Hydrolysis Of

SummaryAn improved method for the preparation of bovine α-thrombin is described. The procedure involves the activation of partially purified prothrombin with tissue thromboplastin followed by chromatography on Sulfopropyl-Sephadex C-50. The purified enzyme is homogeneous on polyacrylamide discontinuous gel electrophoresis and has a specific activity toward fibrinogen of 2,200–2,700 N.I.H. U/mg. Its stability on storage in liquid media is dependent on both ionic strenght and temperature. Increasing ionic strength and decreasing temperature result in optimal stability. The denaturation of α-thrombin by guanidine hydrochloride was found to be a partially reversible process with the renatured species possessing properties similar to “aged” thrombin. In addition, the catalytic properties of a-thrombin covalently attached to agarose gel beads were also examined. The activity of the immobilized enzyme toward fibrinogen was affected to a much greater extent than was the hydrolysis of low molecular weight, synthetic substrates.

Immobilized Nanoparticles-Mediated Enzymatic Hydrolysis of Cellulose for Clean Sugar Production: A Novel Approach

2019 ◽  
Vol 15 (3) ◽  
pp. 296-303 ◽  
Author(s):  
Swapnil Gaikwad ◽  
Avinash P. Ingle ◽  
Silvio Silverio da Silva ◽  
Mahendra Rai
Keyword(s):  
Catalytic Activity ◽  
Enzymatic Hydrolysis ◽  
Immobilized Enzyme ◽  
Free Enzyme ◽  
Magnetic Nanomaterials ◽  
Sugar Production ◽  
Cellulase Enzyme ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

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.

Mass transfer in heterogeneous system enzyme-substrate; Approximate analytical model for the case of liquid substrate-immobilized enzyme

1982 ◽  
Vol 47 (11) ◽  
pp. 3013-3018
Author(s):  
František Kaštánek ◽  
Jindřich Zahradník ◽  
Germanico Ocampo
Keyword(s):  
Mass Transfer ◽  
Heterogeneous System ◽  
Immobilized Enzyme ◽  
Enzymatic Reaction ◽  
Analytical Form ◽  
Approximate Model ◽  
Basic Type ◽  
Reaction Interface ◽  
Enzyme Substrate ◽  
Flow Intensity

Calculation procedure is suggested for flow intensity of substrate toward reaction interface of immobilized enzyme at simultaneous effect of enzymatic reaction and internal diffusion. The approximate model is presented in an analytical form for the basic type of Michaelis-Menten kinetics and for the case of inhibition in excess of substrate.

scholarly journals Self-assembling thermostable chimeras as new platform for arsenic biosensing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rosanna Puopolo ◽  
Ilaria Sorrentino ◽  
Giovanni Gallo ◽  
Alessandra Piscitelli ◽  
Paola Giardina ◽  
...  
Keyword(s):  
Inclusion Bodies ◽  
Association Constant ◽  
Immobilized Enzyme ◽  
Thermus Thermophilus ◽  
Chimeric Protein ◽  
The Self ◽  
Chimeric Proteins ◽  
Self Assembling ◽  
Langmuir Isotherm Model ◽  
Activity Loss

AbstractThe correct immobilization and orientation of enzymes on nanosurfaces is a crucial step either for the realization of biosensors, as well as to guarantee the efficacy of the developed biomaterials. In this work we produced two versions of a chimeric protein, namely ArsC-Vmh2 and Vmh2-ArsC, which combined the self-assembling properties of Vmh2, a hydrophobin from Pleurotus ostreatus, with that of TtArsC, a thermophilic arsenate reductase from Thermus thermophilus; both chimeras were heterologously expressed in Escherichia coli and purified from inclusion bodies. They were characterized for their enzymatic capability to reduce As(V) into As(III), as well as for their immobilization properties on polystyrene and gold in comparison to the native TtArsC. The chimeric proteins immobilized on polystyrene can be reused up to three times and stored for 15 days with 50% of activity loss. Immobilization on gold electrodes showed that both chimeras follow a classic Langmuir isotherm model towards As(III) recognition, with an association constant (KAsIII) between As(III) and the immobilized enzyme, equal to 650 (± 100) L mol−1 for ArsC-Vmh2 and to 1200 (± 300) L mol−1 for Vmh2-ArsC. The results demonstrate that gold-immobilized ArsC-Vmh2 and Vmh2-ArsC can be exploited as electrochemical biosensors to detect As(III).

scholarly journals Effects of morphology and pore size of mesoporous silicas on the efficiency of an immobilized enzyme

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 ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Mesoporous Silica ◽  
Pore Size ◽  
Immobilized Enzyme ◽  
Mesoporous Silicas ◽  
High Loading ◽  
Loading Capacity ◽  
Silica Films

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

scholarly journals Ring-Chain Tautomerism of the 1,4-Oxathiane S,S-Dioxide Anion

1999 ◽  
Vol 23 (6) ◽  
pp. 376-377
Author(s):  
Nashwa Hammad ◽  
Alan G. Sutherland
Keyword(s):  
Vinyl Sulfone

The ring-chain tautomer of the α-sulfonyl anion of 1,4-oxathiane S,S-dioxide can be trapped by addition of alkoxides to the vinyl sulfone; the scope of this reaction is explored.

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