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Arica MY, Altintas B, Bayramoğlu G. Immobilization of laccase onto spacer-arm attached non-porous poly(GMA/EGDMA) beads: application for textile dye degradation. BIORESOURCE TECHNOLOGY 2009; 100:665-669. [PMID: 18768310 DOI: 10.1016/j.biortech.2008.07.038] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 07/21/2008] [Accepted: 07/23/2008] [Indexed: 05/26/2023]
Abstract
Non-porous poly(glycidyl methacrylate/ethyleneglycol dimetacrylate) (poly(GMA/EGDMA)) beads were prepared by suspension polymerization. The enzyme (i.e. laccase) was covalently immobilized onto plain and spacer-arm attached poly(GMA/EGDMA) beads. The amount of immobilized enzyme on the plain and spacer-arm attached beads was determined as 5.6 and 4.9 mg/g, respectively. The maximum activity (V(max)) and Michaelis constant (K(m)) of laccase immobilized on the spacer-arm attached beads, were found to be 77.6 U/min and 0.47 mM, respectively. Finally, the immobilized laccase was operated in a batch system, and textile dye Reactive Red 120 was successfully decolorized in the enzyme reactor.
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Affiliation(s)
- M Yakup Arica
- Gazi University, Faculty of Arts and Sciences, Biochemical Processing and Biomaterial Research Laboratory, 06500 Teknik Okullar, Ankara, Turkey
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Cullen SP, Mandel IC, Gopalan P. Surface-anchored poly(2-vinyl-4,4-dimethyl azlactone) brushes as templates for enzyme immobilization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:13701-13709. [PMID: 18956849 DOI: 10.1021/la8024952] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We explored surface-anchored poly(2-vinyl-4,4-dimethyl azlactone) (PVDMA) brushes as potential templates for protein immobilization. The brushes were grown using atom transfer radical polymerization from surface-anchored initiators and characterized by a combination of ellipsometry, atomic force microscopy, and X-ray photoelectron spectroscopy. RNase A was immobilized as a model enzyme through the nucleophilic attack of azlactone by the amine groups in the lysines located in the protein. The surface density of RNase A increased linearly from 5 to 50 nm. For 50 nm thick poly(2-vinyl-4,4-dimethyl azlactone) brushes, 7.5 microg/cm2 of RNase A was bound. The kinetics and thermodynamics of RNase A immobilization, the activity relative to surface density, and the pH and temperature dependence were examined. A Langmuir-like model for binding kinetics indicates that the kinetics are controlled by the rate of adsorption of RNase A and has an adsorption rate constant, k(ads), of 2.8 x 10(-8) microg(-1) s(-1) cm3. A maximum relative activity of approximately 0.95, which is near the activity of free RNase A, was reached at 1.2 microg/cm2 (approximately 3.0 monolayers) of immobilized RNase A. The immobilized RNase A had a similar temperature and pH dependence as free RNase A, indicating no significant change in conformation. The PVDMA template was extended to other biotechnologically relevant enzymes, such as deoxyribonuclease I, glucose oxidase, glucoamylase, and trypsin, with relative activities higher than or comparable to those of enzymes immobilized by other means. PVDMA brushes offer an efficient route to immobilize proteins via the ring opening of azlactone without the need for activation or pretreatment while retaining high relative activities of the bound enzymes.
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Affiliation(s)
- Sean P Cullen
- Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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53
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Invertase embedded-PVC tubing as a flow-through reactor aimed at conversion of sucrose into inverted sugar. Enzyme Microb Technol 2008. [DOI: 10.1016/j.enzmictec.2008.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Tyagi C, Tomar L, Singh H. Glycidyl methacrylate-co-N-vinyl-2-pyrrolidone coated polypropylene strips: synthesis, characterization and standardization for dot-enzyme linked immunosorbent assay. Anal Chim Acta 2008; 632:256-65. [PMID: 19110102 DOI: 10.1016/j.aca.2008.11.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2008] [Revised: 10/31/2008] [Accepted: 11/04/2008] [Indexed: 11/19/2022]
Abstract
Glycidyl methacrylate and N-vinyl-2-pyrrolidone (GMA-co-NVP) copolymers with various GMA:NVP ratios were synthesized by solution polymerization technique in toluene using 2,2'-azobisisobutyronitrile (AIBN) as free radical initiator and dip coated onto polypropylene strips. The copolymer composition in polymeric coatings was confirmed by proton NMR spectroscopy. Various techniques like FTIR, SEM and contact angle were used for surface characterization of the polymer coatings. These polymer coated strips were evaluated and standardized for their application in dot-ELISA in two steps. In first step, specificity, sensitivity and reproducibility of the assay on developed polymer coated strips was evaluated through a model system using rabbit anti-goat IgG, goat anti-rabbit IgG and goat anti-rabbit IgG HRP (horseradish peroxidase)-conjugate. Polymer coating with GMA-NVP mol% ratio of 78:22 was able to detect rabbit anti-goat IgG antibody at a concentration as low as 2 ng mL(-1) with 1% BSA as blocking agent using antispecies IgG peroxidase conjugate diluted 1500 times. In the second step, the sensitivity and specificity of the developed system was established with human blood and finally used to identify the source of mosquito blood meal which is an important parameter in epidemiological studies, particularly in determining the role of mosquito in malaria transmission. The time duration of standardized assay with developed polymer coated strips was cut down to one hour compared to the 3-4h required in usual dot-ELISA.
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Affiliation(s)
- Charu Tyagi
- Centre for Biomedical Engineering, Indian Institute of Technology, Delhi, India.
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de Los Angeles Calixto-Romo M, Santiago-Hernández JA, Vallejo-Becerra V, Amaya-Delgado L, del Carmen Montes-Horcasitas M, Hidalgo-Lara ME. Expression, purification and immobilization of the intracellular invertase INVA, from Zymomonas mobilis on crystalline cellulose and Nylon-6. J Ind Microbiol Biotechnol 2008; 35:1455-63. [PMID: 18712537 DOI: 10.1007/s10295-008-0447-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 07/30/2008] [Indexed: 11/25/2022]
Abstract
This paper presents two immobilization methods for the intracellular invertase (INVA), from Zymomonas mobilis. In the first method, a chimeric protein containing the invertase INVA, fused through its C-terminus to CBDCex from Cellulomonas fimi was expressed in Escherichia coli strain BL21 (DE3). INVA was purified and immobilized on crystalline cellulose (Avicel) by means of affinity, in a single step. No changes were detected in optimal pH and temperature when INVA-CBD was immobilized on Avicel, where values of 5.5 and 30 degrees C, respectively, were registered. The kinetic parameters of the INVA-CBD fusion protein were determined in both its free form and when immobilized on Avicel. Km and Vmax were affected with immobilization, since both showed an increase of up to threefold. Additionally, we found that subsequent to immobilization, the INVA-CBD fusion protein was 39% more susceptible to substrate inhibition than INVA-CBD in its free form. The second method of immobilization was achieved by the expression of a 6xHis-tagged invertase purified on Ni-NTA resin, which was then immobilized on Nylon-6 by covalent binding. An optimal pH of 5.5 and a temperature of 30 degrees C were maintained, subsequent to immobilization on Nylon-6 as well as with immobilization on crystalline cellulose. The kinetic parameters relating to Vmax increased up to 5.7-fold, following immobilization, whereas Km increased up to 1.7-fold. The two methods were compared showing that when invertase was immobilized on Nylon-6, its activity was 1.9 times that when immobilized on cellulose for substrate concentrations ranging from 30 to 390 mM of sucrose.
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Affiliation(s)
- María de Los Angeles Calixto-Romo
- Departamento de Biotecnología y Bioingeniería, CINVESTAV-IPN. Av. Instituto Politécnico, Nacional 2508 Col. San Pedro Zacatenco, CP 07360, Mexico D.F., Mexico
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57
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Bayramoğlu G, Arica MY. Enzymatic removal of phenol and p-chlorophenol in enzyme reactor: horseradish peroxidase immobilized on magnetic beads. JOURNAL OF HAZARDOUS MATERIALS 2008; 156:148-155. [PMID: 18207637 DOI: 10.1016/j.jhazmat.2007.12.008] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2007] [Revised: 12/04/2007] [Accepted: 12/05/2007] [Indexed: 05/25/2023]
Abstract
Horseradish peroxidase was immobilized on the magnetic poly(glycidylmethacrylate-co-methylmethacrylate) (poly(GMA-MMA)), via covalent bonding and used for the treatment of phenolic wastewater in continuous systems. For this purposes, horseradish peroxidase (HRP) was covalently immobilized onto magnetic poly(GMA-MMA) beds using glutaraldehyde (GA) as a coupling agent. The maximum HRP immobilization capacity of the magnetic poly(GMA-MMA)-GA beads was 3.35 mg g(-1). The immobilized HRP retained 79% of the activity of the free HRP used for immobilization. The immobilized HRP was used for the removal of phenol and p-chlorophenol via polymerization of dissolved phenols in the presence of hydrogen peroxide (H(2)O(2)). The effect of pH and temperature on the phenol oxidation rate was investigated. The results were compared with the free HRP, which showed that the optimum pH value for the immobilized HRP is similar to that for the free HRP. The optimum pH value for free and immobilized HRP was observed at pH 7.0. The optimum temperature for phenols oxidation with immobilized HRP was between 25 and 35 degrees C and the immobilized HRP has more resistance to temperature inactivation than that of the free form. Finally, the immobilized HRP was operated in a magnetically stabilized fluidized bed reactor, and phenols were successfully removed in the enzyme reactor.
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Affiliation(s)
- Gülay Bayramoğlu
- Biochemical Processing and Biomaterial Research Laboratory, Faculty of Science, Kirikkale University, Yahşihan-Kirikkale, Turkey
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58
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Shaheen I, Bhatti HN, Ashraf T. Production, purification and thermal characterisation of invertase from a newly isolated Fusarium sp. under solid-state fermentation. Int J Food Sci Technol 2008. [DOI: 10.1111/j.1365-2621.2007.01581.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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59
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Cullen SP, Liu X, Mandel IC, Himpsel FJ, Gopalan P. Polymeric brushes as functional templates for immobilizing ribonuclease A: study of binding kinetics and activity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:913-920. [PMID: 18076197 DOI: 10.1021/la702510z] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The ability to immobilize proteins with high binding capacities on surfaces while maintaining their activity is critical for protein microarrays and other biotechnological applications. We employed poly(acrylic acid) (PAA) brushes as templates to immobilize ribonuclease A (RNase A), which is commonly used to remove RNA from plasmid DNA preparations. The brushes are grown by surface-anchored atom-transfer radical polymerization (ATRP) initiators. RNase A was immobilized by both covalent esterification and a high binding capacity metal-ion complexation method to PAA brushes. The polymer brushes immobilized 30 times more enzyme compared to self-assembled monolayers. As the thickness of the brush increases, the surface density of the RNase A increases monotonically. The immobilization was investigated by ellipsometry, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and near-edge X-ray absorption fine structure spectroscopy (NEXAFS). The activity of the immobilized RNase A was determined using UV absorbance. As much as 11.0 microg/cm(2) of RNase A was bound to PAA brushes by metal-ion complexation compared to 5.8 microg/cm(2) by covalent immobilization which is 30 and 16 times the estimated mass bound in a monolayer. The calculated diffusion coefficient D was 0.63 x 10(-14) cm(2)/s for metal-ion complexation and 0.71 x 10(-14) cm(2)/s for covalent immobilization. Similar values of D indicate that the binding kinetics is similar, but the thermodynamic equilibrium coverage varies with the binding chemistry. Immobilization kinetics and thermodynamics were characterized by ellipsometry for both methods. A maximum relative activity of 0.70-0.80 was reached between five and nine monolayers of the immobilized enzyme. However, the relative activity for covalent immobilization was greater than that of metal-ion complexation. Covalent esterification resulted in similar temperature dependence as free enzyme, whereas metal-ion complexation showed no temperature dependence indicating a significant change in conformation.
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Affiliation(s)
- Sean P Cullen
- Chemical and Biological Engineering, Department of Physics, and Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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60
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Bayramoğlu G, Kiralp S, Yilmaz M, Toppare L, Arıca MY. Covalent immobilization of chloroperoxidase onto magnetic beads: Catalytic properties and stability. Biochem Eng J 2008. [DOI: 10.1016/j.bej.2007.06.018] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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61
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Goddard JM, Hotchkiss JH. Tailored functionalization of low-density polyethylene surfaces. J Appl Polym Sci 2008. [DOI: 10.1002/app.27209] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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63
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Bayramoglu G, Tunali Y, Arica MY. Immobilization of β-galactosidase onto magnetic poly(GMA–MMA) beads for hydrolysis of lactose in bed reactor. CATAL COMMUN 2007. [DOI: 10.1016/j.catcom.2006.10.029] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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64
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Catana R, Eloy M, Rocha J, Ferreira B, Cabral J, Fernandes P. Stability evaluation of an immobilized enzyme system for inulin hydrolysis. Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.01.042] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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65
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Goddard J, Talbert J, Hotchkiss J. Covalent Attachment of Lactase to Low-Density Polyethylene Films. J Food Sci 2007; 72:E036-41. [DOI: 10.1111/j.1750-3841.2006.00203.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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66
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Santiago-Hernández J, Vásquez-Bahena J, Calixto-Romo M, Xoconostle-Cázares G, Ortega-López J, Ruíz-Medrano R, Montes-Horcasitas M, Hidalgo-Lara M. Direct immobilization of a recombinant invertase to Avicel by E. coli overexpression of a fusion protein containing the extracellular invertase from Zymomonas mobilis and the carbohydrate-binding domain CBDCex from Cellulomonas fimi. Enzyme Microb Technol 2006. [DOI: 10.1016/j.enzmictec.2005.10.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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67
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Altinok H, Aksoy S, Tümtürk H, Hasirci N. Covalent immobilization of invertase on chemically activated poly(2-hydroxyethyl methacrylate) microbeads. Russ Chem Bull 2006. [DOI: 10.1007/s11172-006-0499-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Poly(phenylene oxide) films modified with allylamine plasma as a support for invertase immobilization. Eur Polym J 2006. [DOI: 10.1016/j.eurpolymj.2006.07.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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69
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David AE, Wang NS, Yang VC, Yang AJ. Chemically surface modified gel (CSMG): An excellent enzyme-immobilization matrix for industrial processes. J Biotechnol 2006; 125:395-407. [PMID: 16644049 DOI: 10.1016/j.jbiotec.2006.03.019] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 02/10/2006] [Accepted: 03/13/2006] [Indexed: 11/27/2022]
Abstract
Invertase from S. cerevisiae has been immobilized on porous silica matrix, formed using sol-gel chemistry, with surface area of approximately 650 m(2)/g. The co-condensation of silica sol with 3-aminopropyl(triethoxy)silane produced an amino-chemically surface modified silica gel (N-CSMG) with a very high ligand loading of 3.6 mmol/g SiO(2); significantly higher than commercially available matrices. Surface amine groups were activated with glutaraldehyde to produce GA-N-CSMG, and invertase covalently attached by the aldehyde. Invertase was used as a model enzyme to measure the immobilizing character of the GA-N-CSMG material. Using an optimized immobilization protocol, a very high loading of 723 mg invertase per gram GA-N-CSMG is obtained; 3-200-fold higher than values published in literature. The reproducible, immobilized activity of 246,000 U/g GA-N-CSMG is also greater than any other in literature. Immobilized invertase showed almost 99% retention of free enzyme activity and no loss in catalytic efficiency. The apparent kinetic parameters K(M) and V(M) were determined using the Michealis-Menten kinetic model. K(M) of the free invertase was 1.5 times greater than that of the immobilized invertase--indicating a higher substrate affinity of the immobilized invertase. These findings show considerable promise for this material as an immobilization matrix in industrial processes.
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Affiliation(s)
- Allan E David
- Department of Chemical Engineering, A. James Clark School of Engineering, University of Maryland, College Park, MD 20742, United States
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70
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Bhatti HN, Asgher M, Abbas A, Nawaz R, Sheikh MA. Studies on kinetics and thermostability of a novel acid invertase from Fusarium solani. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2006; 54:4617-23. [PMID: 16787006 DOI: 10.1021/jf053194g] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The present investigation deals with purification and thermal characterization of an acid invertase produced by Fusarium solani in submerged culture. The maximum enzyme activity (9.90 U mL(-1)) was achieved after 96 h of cultivation at pH 5.0 and 30 degrees C in a basal medium containing molasses (2%) as the carbon and energy source supplemented with 1% peptone. Invertase was purified by ammonium sulfate fractionation and column chromatography on DEAE-cellulose and Sephadex G-200. The purified enzyme was proven to be homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The molecular mass of the enzyme was 65 kDa. The optimum pH and temperature for activity were 2.6 and 50 degrees C, respectively. The Km value for sucrose was 3.57 mM with an activation energy of 4.056 kJ mol(-1). Enthalpies of activation (DeltaH) were decreased while entropies (DeltaS) of activation increased at higher temperatures. The effects of alpha-chymotrypsin and 4 M urea were tetraphasic with periodic gain and loss of enzyme activity. A possible explanation for the thermal inactivation of invertase at higher temperatures is also discussed.
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Affiliation(s)
- Haq Nawaz Bhatti
- Department of Chemistry, University of Agriculture, Faisalabad, Pakistan, 38040
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71
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Pérez JPH, López-Cabarcos E, López-Ruiz B. The application of methacrylate-based polymers to enzyme biosensors. ACTA ACUST UNITED AC 2006; 23:233-45. [PMID: 16880004 DOI: 10.1016/j.bioeng.2006.06.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Revised: 06/19/2006] [Accepted: 06/19/2006] [Indexed: 10/24/2022]
Abstract
Enzyme electrodes based on methacrylates have received significant attention in the development of biosensors. This article reviews the use and application of methacrylate and its derivatives as an immobilization system for the preparation of enzyme electrodes. Resent examples, extracted from the literature, illustrate the superior performance of such materials in the fabrication of biosensors and bioreactors.
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Affiliation(s)
- J P Hervás Pérez
- Sección Departamental de Química Analítica, Facultad de Farmacia, Universidad Complutense de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain
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72
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Sanjay G, Sugunan S. Enhanced pH and thermal stabilities of invertase immobilized on montmorillonite K-10. Food Chem 2006. [DOI: 10.1016/j.foodchem.2004.12.043] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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73
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Arıca MY, Bayramoğlu G. Invertase reversibly immobilized onto polyethylenimine-grafted poly(GMA–MMA) beads for sucrose hydrolysis. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcatb.2005.12.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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74
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Osman B, Kara A, Uzun L, Beşirli N, Denizli A. Vinyl imidazole carrying metal-chelated beads for reversible use in yeast invertase adsorption. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.molcatb.2005.09.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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75
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Kang K, Kan C, Yeung A, Liu D. The Properties of Covalently Immobilized Trypsin on Soap-Free P(MMA-EA-AA) Latex Particles. Macromol Biosci 2005; 5:344-51. [PMID: 15818587 DOI: 10.1002/mabi.200400178] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The covalent immobilization of trypsin onto poly[(methyl methacrylate)-co-(ethyl acrylate)-co-(acrylic acid)] latex particles, produced by a soap-free emulsion polymerization technique, was carried out using the carbodiimide method. The catalytic properties and kinetic parameters, as well as the stability of the immobilized enzyme were compared to those of the free enzyme. Results showed that the optimum temperature and pH for the immobilized trypsin in the hydrolysis of casein were 55 degrees C and 8.5, both of which were higher than that of the free form. It was found that K(m) (Michaelis constant) was 45.7 mg . ml(-1) and V(max) (maximal reaction rate) was 793.0 microg . min(-1) for immobilized trypsin, compared to a K(m) of 30.0 mg . ml(-1) and a V(max) of 5 467.5 microg . min(-1) for free trypsin. The immobilized trypsin exhibited much better thermal and chemical stabilities than its free counterpart and maintained over 63% of its initial activity after reusing ten times.
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Affiliation(s)
- Kai Kang
- Department of Chemical Engineering, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
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76
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Bean LS, Heng LY, Yamin BM, Ahmad M. The electrochemical behaviour of ferrocene in a photocurable poly(methyl methacrylate-co-2-hydroxylethyl methacrylate) film for a glucose biosensor. Bioelectrochemistry 2005; 65:157-62. [PMID: 15713567 DOI: 10.1016/j.bioelechem.2004.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Revised: 11/08/2004] [Accepted: 11/17/2004] [Indexed: 11/22/2022]
Abstract
A single-step fabrication of a glucose biosensor with simultaneous immobilization of both ferrocene mediator and glucose oxidase in a photocurable methacrylic film consisting of poly(methyl methacrylate-co-2-hydroxylethyl methacrylate) was reported. The entrapped ferrocene showed reversible redox behaviour in the photocured film and no significant leaching of both entrapped ferrocene and enzyme glucose oxidase was observed because of the low water absorption properties of the co-polymer films. From electrochemical studies, ferrocene entrapped in the co-polymer film demonstrated slow diffusion properties. A linear glucose response range of 2-11 mM was obtained at low applied potential of +0.25 V. The glucose biosensor fabricated by this photocuring method yielded sensor reproducibility and repeatability with relative standard deviation of <10% and long-term stability of up to 14 days. The main advantage of the use of photocurable procedure is that biosensor membrane fabrication can be performed in a single step without any lengthy chemical immobilization of enzyme.
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Affiliation(s)
- Low Sim Bean
- School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
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77
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Arıca M, Bayramoğlu G. Polyethyleneimine-grafted poly(hydroxyethyl methacrylate-co-glycidyl methacrylate) membranes for reversible glucose oxidase immobilization. Biochem Eng J 2004. [DOI: 10.1016/j.bej.2004.04.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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78
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Bayramoğlu G, Yilmaz M, Arica M. Immobilization of a thermostable α-amylase onto reactive membranes: kinetics characterization and application to continuous starch hydrolysis. Food Chem 2004. [DOI: 10.1016/s0308-8146(03)00283-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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79
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Bayramoğlu G, Altınok H, Bulut A, Denizli A, Arıca M. Preparation and application of spacer-arm-attached poly(hydroxyethyl methacrylate-co-glycidyl methacrylate) films for urease immobilisation. REACT FUNCT POLYM 2003. [DOI: 10.1016/s1381-5148(03)00050-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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