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Niyaz Ahmed L, Thomas P. Analytical expression for the model that describes the heterogeneous reaction-diffusion process with immobilized enzyme (penicillin G acylase). Heliyon 2023; 9:e21998. [PMID: 38045190 PMCID: PMC10692794 DOI: 10.1016/j.heliyon.2023.e21998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/21/2023] [Accepted: 11/01/2023] [Indexed: 12/05/2023] Open
Abstract
This research article examines the reaction-diffusion process in an immobilized enzyme batch reactor. The model incorporates strongly non-linear factors that are associated with standard Michaelis-Menten kinetics. The non-linear reaction-diffusion equations for substrate and product concentrations have been approximated analytically. Employing two different semi-analytical methods, Akbari-Ganji's method (AGM) and the modified Adomian decomposition method (MADM), to compute the dimensionless steady-state solutions to the system of non-linear differential equations for all values of reaction parameters. In addition, the dynamics of the mean integrated effectiveness factor of penicillin acylase in porous spherical particles have been presented for the determination of the local effectiveness factor. In order to gauge the potency of our proposed solution, we compare two semi-analytical results with a numerical result that are in good agreement across the whole concentration range. The proposed formulation aims to simulate the dynamic performance of the system utilizing the parameters and would enhance the determination of the optimum particle size for enzyme catalysts.
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Affiliation(s)
- L. Niyaz Ahmed
- Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, 632 014, Tamil Nadu, India
| | - Praveen Thomas
- Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology, Vellore, 632 014, Tamil Nadu, India
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Weishaupt R, Siqueira G, Schubert M, Tingaut P, Maniura-Weber K, Zimmermann T, Thöny-Meyer L, Faccio G, Ihssen J. TEMPO-Oxidized Nanofibrillated Cellulose as a High Density Carrier for Bioactive Molecules. Biomacromolecules 2015; 16:3640-50. [DOI: 10.1021/acs.biomac.5b01100] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ramon Weishaupt
- Laboratory
for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, CH-9014 St. Gallen, Switzerland
| | - Gilberto Siqueira
- Laboratory
for Applied Wood Materials, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Mark Schubert
- Laboratory
for Applied Wood Materials, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Philippe Tingaut
- Laboratory
for Applied Wood Materials, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Katharina Maniura-Weber
- Laboratory
for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, CH-9014 St. Gallen, Switzerland
| | - Tanja Zimmermann
- Laboratory
for Applied Wood Materials, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | - Linda Thöny-Meyer
- Laboratory
for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, CH-9014 St. Gallen, Switzerland
| | - Greta Faccio
- Laboratory
for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, CH-9014 St. Gallen, Switzerland
| | - Julian Ihssen
- Laboratory
for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, CH-9014 St. Gallen, Switzerland
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Effect of Diffusion on Discoloration of Congo Red by Alginate Entrapped Turnip (Brassica rapa) Peroxidase. Enzyme Res 2015; 2015:575618. [PMID: 25734011 PMCID: PMC4334939 DOI: 10.1155/2015/575618] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 01/16/2015] [Accepted: 01/20/2015] [Indexed: 11/22/2022] Open
Abstract
Enzymatic discoloration of the diazo dye, Congo red (CR), by immobilized plant peroxidase from turnip “Brassica rapa” is investigated. Partially purified turnip peroxidase (TP) was immobilized by entrapment in spherical particles of calcium alginate and was assayed for the discoloration of aqueous CR solution. Experimental data revealed that pH, reaction time, temperature, colorant, and H2O2 concentration play a significant role in dye degradation. Maximum CR removal was found at pH 2.0, constant temperature of 40°C in the presence of 10 mM H2O2, and 180 mg/L of CR. More than 94% of CR was removed by alginate immobilized TP after 1 h of incubation in a batch process under optimal conditions. About 74% removal efficiency was retained after four recycles. Diffusional limitations in alginate beads such as effectiveness factor η, Thiele modulus Φ, and effective diffusion coefficients (De) of Congo red were predicted assuming a first-order biodegradation kinetic. Results showed that intraparticle diffusion resistance has a significant effect on the CR biodegradation rate.
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Tse PH, Leypoldt JK, Gough DA. Determination of the intrinsic kinetic constants of immobilized glucose oxidase and catalase. Biotechnol Bioeng 2012; 29:696-704. [PMID: 18576504 DOI: 10.1002/bit.260290606] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Models of membrane systems containing immobilized glucose oxidase and catalase operating together or independently have been developed. A rotated disk electrode apparatus was employed with novel electrochemical operating conditions to experimentally determine mass transfer and intrinsic kinetic parameters of enzyme-containing membranes. The value of a mass transfer parameter that describes internal and external diffusion was first determined under conditions that do not permit the enzyme reactions. In a subsequent experiment with the reaction allowed, kinetic parameters corresponding to the intrinsic maximal velocity and Michaelis constants of the immobilized enzymes were estimated by regression analysis of data based on an appropriate two- or three- parameter model. It was found that immobilization reduced the maximal intrinsic velocity but had no detectable effect on the Michaelis constants. In all but one case- these methods for membrane characterization are nondestructive and can be used repeatedly on a given membrane. These techniques provide the means for quantitative comparisons of immobilization methods and make possible temporal studies of immobilized enzyme inactivation.
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Affiliation(s)
- P H Tse
- Department of Applied Mechanics and Engineering Sciences, Bioengineering Group, University of California, San Diego, La Jolla, California 92093
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Valencia P, Flores S, Wilson L, Illanes A. Effect of particle size distribution on the simulation of immobilized enzyme reactor performance. Biochem Eng J 2010. [DOI: 10.1016/j.bej.2010.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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6
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Godjevargova T, Gabrovska K. Influence of matrix on external mass transfer resistance in immobilized urease membranes. Enzyme Microb Technol 2006. [DOI: 10.1016/j.enzmictec.2004.10.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Khorasheh F, Kheirolomoom A, Mireshghi S. Application of an optimization algorithm for estimating intrinsic kinetic parameters of immobilized enzymes. J Biosci Bioeng 2002. [DOI: 10.1016/s1389-1723(02)80108-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Abstract
Proteins and enzymes are now generally thought to be organized within the cell to form clusters in a dynamic and versatile way, and heterologous protein-protein interactions are believed to be involved in virtually all cellular events. Therefore we need appropriate tools to detect and study such interactions. Chromatographic techniques prove to be well suited for this kind of investigation. Real complexes formed between proteins can be studied by classic gel filtration. When enzymes are studied, active enzyme gel chromatography is a useful alternative. A variant of classic gel filtration is gel filtration equilibrium analysis, which is similar to equilibrium dialysis. When the association formed is only dynamic and equilibrates very rapidly, either the Hummel-Dryer method of equilibrium gel filtration or large-zone equilibrium filtration sometimes allows the interactions to be analyzed, both qualitatively and quantitatively. Very often, however, interactions between enzymes and proteins can only be evidenced in vitro in media that mimic the intracellular situation. Immobilized proteins are excellent tools for this type of research. Several examples are indeed known where the immobilization of an enzyme on a solid support does not affect its real properties, but rather changes its environment in such a way that the diffusion becomes limiting. Affinity chromatography using immobilized proteins allows the analysis of heterologous protein-protein interactions, both qualitatively and quantitatively. A useful alternative appears to be affinity electrophoresis. The latter technique, however, is exclusively qualitative. All these techniques are described and illustrated with examples taken from the literature.
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Affiliation(s)
- S Beeckmans
- Laboratory of Protein Chemistry, Vrije Universiteit Brussel, Paardenstraat 65, Sint-Genesius-Rode, B-1640, Belgium.
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Kotha A, Raman RC, Ponrathnam S, Kumar KK, Shewale JG. Beaded reactive polymers. 3. Effect of triacrylates as crosslinkers on the physical properties of glycidyl methacrylate copolymers and immobilization of penicillin G acylase. Appl Biochem Biotechnol 1998; 74:191-203. [PMID: 10052115 DOI: 10.1007/bf02825965] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Various glycidyl methacrylate (GMA) copolymers were synthesized by suspension polymerization, using pentaerythritol triacrylate (PETA), trimethylolpropane triacrylate (TMPTA), and trimethylolpropane trimethacrylate (TRIM) as crosslinking comonomers. These copolymers were evaluated for the immobilization of penicillin G acylase. Broad pore-size distribution that was observed was in the range 5-300 nm. Both surface area and pore volume increased with increase in the mole fraction of crosslinking comonomer (increasing crosslink density). The pore volume of the copolymers was more than doubled by including lauryl alcohol as porogen. Binding of penicillin G acylase (PGA) was quantitative on highly crosslinked copolymers. The expression of bound PGA was better on the relatively more hydrophilic GMA-TMPTA and GMA-PETA copolymer supports compared to the GMA-TRIM copolymers. Among the different copolymers studied, GMA-TMPTA copolymer 7411 exhibited highest activity of immobilized penicillin G acylase (167.4 IU/g) with 35.1% expression.
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Affiliation(s)
- A Kotha
- Chemical Engineering Division, National Chemical Laboratory, India
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Kotha A, Raman RC, Ponrathnam S, Kumar KK, Shewale JG. Beaded reactive polymers, 2. Immobilisation of penicillin G acylase on glycidyl methacrylate-divinyl benzene copolymers of differing pore size and its distribution. REACT FUNCT POLYM 1996. [DOI: 10.1016/1381-5148(95)00089-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Schmidt P, Rosenfeld E, Millner R, Czerner R, Schellenberger A. Theoretical and experimental studies on the influence of ultrasound on immobilized enzymes. Biotechnol Bioeng 1987; 30:928-35. [DOI: 10.1002/bit.260300803] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Invertase immobilized on macroporous polystyrene: Properties and kinetic characterization. Biotechnol Bioeng 1987; 29:72-8. [DOI: 10.1002/bit.260290111] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Owusu RK, Finch A. Flow microcalorimetric study of immobilized enzyme kinetics using the co-immobilized glucose oxidase-catalase system. BIOCHIMICA ET BIOPHYSICA ACTA 1986; 872:83-91. [PMID: 3730398 DOI: 10.1016/0167-4838(86)90150-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The kinetics of the bi-substrate enzyme glucose oxidase (EC 1.1.3.4) (with catalase, EC 1.11.1.6) co-immobilized on glass was studied using flow microcalorimetry. Oxygen and glucose external-internal diffusion effects were resolved.
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Analysis of diffusion effects on immobilized enzymes on porous supports with reversible Michaelis-Menten kinetics. Enzyme Microb Technol 1986. [DOI: 10.1016/0141-0229(86)90153-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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16
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Owusu RK, Trewhella MJ, Finch A. Flow microcalorimetric study of immobilized enzyme kinetics using the urea-immobilized urease system. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/0167-4838(85)90284-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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17
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Kreuzer F, Hoofd L. Facilitated diffusion of oxygen: possible significance in blood and muscle. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1984; 169:3-21. [PMID: 6375299 DOI: 10.1007/978-1-4684-1188-1_1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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18
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Kovalenko GA, Sokolovskii VD. Immobilization of oxyreductases on inorganic supports based on alumina-immobilization of alcohol dehydrogenase on nonmodified and modified alumina. Biotechnol Bioeng 1983; 25:3177-84. [DOI: 10.1002/bit.260251228] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Iqbal J, Saleemuddin M. Activity and stability of glucose oxidase and invertase immobilized on Concanavalin A sepharose: Influence of lectin concentrations. Biotechnol Bioeng 1983; 25:3191-5. [DOI: 10.1002/bit.260251230] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
The effect of mass transfer resistances on the Lineweaver-Burk plots in immobilized enzyme systems has been investigated numerically and with analytical approximate solutions. While Hamilton, Gardner & Colton (1974) studied the effect of internal diffusion resistances in planar geometry, our study was extended to the combined effect of internal and external diffusion in cylindrical and spherical geometries as well. The variation of Lineweaver-Burk plots with respect to the geometries was minimized by modifying the Thiele modulus and the Biot number with the shape factor. Especially for a small Biot number all the three Lineweaver-Burk plots fell on a single line. As was discussed by Hamilton et al. (1974), the curvature of the line for large external diffusion resistances was small enough to be assumed linear, which was confirmed from the two approximate solutions for large and small substrate concentrations. Two methods for obtaining intrinsic kinetic constants were proposed: First, we obtained both maximum reaction rate and Michaelis constant by fitting experimental data to a straight line where external diffusion resistance was relatively large, and second, we obtained Michaelis constant from apparent Michaelis constant from the figure in case we knew maximum reaction rate a priori.
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Aguirre R, Kasche V. Catalytically active monomer forms of immobilized arginase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1983; 130:373-81. [PMID: 6825701 DOI: 10.1111/j.1432-1033.1983.tb07163.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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22
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Correlation of experimental and theoretical data for artificial and natural systems with immobilized biocatalysts. Enzyme Microb Technol 1983. [DOI: 10.1016/0141-0229(83)90056-x] [Citation(s) in RCA: 51] [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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Müller J, Zwing T. An experimental verification of the theory of diffusion limitation of immobilized enzymes. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 705:117-23. [PMID: 7115728 DOI: 10.1016/0167-4838(82)90343-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) was covalently bound to Sepharose beads. Kinetic measurements with the substrate p-nitrophenyl phosphate gave the following results. Effectiveness factors were decreasing with increasing bound activity, decreasing substrate concentration, and increasing particle radius of the beads. With decreasing effectiveness factors, the apparent Michaelis constants were decreasing. Preparations with high bound activities did not obey Michaelis-Menten kinetics at substrate concentrations much higher than the apparent Michaelis constants. The experimental results accorded quantitatively with the theory of diffusion limitation (Engasser, J.M. (1978) Biochim. Biophys. Acta 526, 301-310).
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Kinetics of immobilized pig heart fumarase. Appl Biochem Biotechnol 1982; 7:177-88. [DOI: 10.1007/bf02798295] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/1981] [Accepted: 09/14/1981] [Indexed: 10/22/2022]
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Aguirre R, Hatchikian EC, Monsan P, Cocquempot MF, Lissolo T. Utilization of free and immobilized Desulfovibrio hydrogenase in hydrogen photoproduction : Coupling efficiency of cytochrome C3, ferredoxin and flavodoxin. Biotechnol Lett 1982. [DOI: 10.1007/bf00132829] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Sémériva M, Varesi L, Gratecos D. Studies on transport of amino acids from peptides by rat small intestine in vitro. Synthesis, properties and uptake of a photosensitive tetrapeptide. EUROPEAN JOURNAL OF BIOCHEMISTRY 1982; 122:619-26. [PMID: 6120839 DOI: 10.1111/j.1432-1033.1982.tb06484.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
By comparison with what is known of disaccharides transport, it has been suggested that intestinal aminopeptidase N could, hydrolyze, on the surface of the microvillus membrane, oligopeptides longer than tripeptides and itself subserve the translocation function for the amino acids released from these peptides. This article describes the synthesis of the tritiated azido-tetrapeptides p-azido[3H]phenylalanyl-alanyl-glycyl-glycine containing L or D-alanine. The synthesized products possess a function which displays all the characteristics of an aryl-azide. The photosensitive tetrapeptide formed with LAla-Gly-Gly is as good a substrate for porcine and rat aminopeptidases N as unmodified peptides while the tetrapeptide formed with DLa-Gly-Gly is not hydrolyzed at all. In addition a pattern of stepwise hydrolysis could be demonstrated and aminopeptidase N is the only exopeptidase present in the mucosal cells capable of utilizing the modified tetrapeptide as substrate. Uptake assays performed on everted rings of jejunum with the azido-tetrapeptide as substrate have shown that: (a) the azido-tetrapeptide is not transported intact but must be hydrolyzed first; (b) p-azido-phenylalanine is not released in the external medium and therefore its observed uptake is not from the bulk medium and (c) the azido-D-tetrapeptide is only accumulated by passive diffusion. These observations suggest the presence on the brush border membrane of an aminopeptidase-related transport system.
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Lee GK, Lesch RA, Reilly PJ. Estimation of intrinsic kinetic constants for pore diffusion-limited immobilized enzyme reactions. Biotechnol Bioeng 1981. [DOI: 10.1002/bit.260230303] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Cherednikova TV, Muronetz VI, Nagradova NK. Study of subunit interactions in immobilized D-glyceraldehyde-3-phosphate dehydrogenase. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 613:292-308. [PMID: 7004490 DOI: 10.1016/0005-2744(80)90084-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Under conditions which cause dissociation of soluble tetrameric glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12) into inactive dimers, immobilized apoenzymes from yeast and rat skeletal muscle coupled to CnBr-activated Sepharose via one subunit retain 50% of matrix-bound protein with unaltered specific activity. The solubilized dissociated species are inactive. Two molecules of NAD+ (NADH) firmly bound to the immobilized rat muscle tetramer can prevent the dissociation. Immobilized dimer was demonstrated to bind one molecule of coenzyme with high affinity. Using various combinations of immobilized and soluble rat muscle and yeast dimers, we succeeded in reconstituting tetramers, containing one molecule of NAD+ bound either to a matrix-linked or to a non-covalently bound dimer. In the latter case, the dissociation of the tetramer was completely prevented. This suggests that the binding of a single coenzyme molecule is sufficient to stabilize the interdimeric contacts provided the neighbouring dimer is stabilized independently. Such stabilization is produced by the covalent binding of one of the subunits comprising the dimer to the matrix. The structure of the dimer as a whole becomes resistant to the action of the dissociating agent. The effect appears to be cooperative and similar to that of NAD+ or NADH. The dissociation of the immobilized tetramer is, most likely, the result of conformational changes, affecting the structure of the non-covalently bound dimer. Any factor, capable of preventing these changes, would stabilize the interdimeric contacts. The latter conclusion is substantiated by the effect of specific antibodies, which prevent the dissociation of the immobilized tetramer by forming a complex with the dimer, non-covalently bound to the matrix. The evidence obtained in the present investigation supports the conclusion that the isolated dimer of glyceraldehyde-3-phosphate dehydrogenase represents a relatively independent structural and functional 'unit' of the enzyme. It can be stabilized in a catalytically active form by interactions other than those involved in inter-dimeric contacts in the tetramer. The kinetics of the association of immobilized and soluble dimers have been studied. Association rate constants were determined for homologous (yeast-yeast, rat-rat) and heterologous (yeast-rat, yeast-rabbit) dimer combinations. The binding of one molecule of specific antibody to the immobilized dimer was shown to increase the rate constant of association.
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Beitz J, Schellenberger A, Lasch J, Fischer J. Catalytic properties and electrostatic potential of charged immobilized enzyme derivatives. Pyruvate decarboxylase attached to cationic polystyrene beads of different charge densities. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 612:451-4. [PMID: 7370280 DOI: 10.1016/0005-2744(80)90127-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Pyruvate decarboxylase has been covalently attached to positively charged macroporous polystyrene resins. The changes in the functional behaviour of the enzyme resulting from the electrostatic interaction of the cationic carrier polymer and the anionic substrate have been studied as function of the fixed charge concentration of the carrier. The findings confirm the connection of two widely used theoretical expressions relating electrostatic parameters with Michaelis constants.
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Muronetz VI, Zueva VS, Nagradova NK. Half-of-the-sites reactivity in immobilized hybrids of glyceraldehyde-3-phosphate dehydrogenase. FEBS Lett 1979; 107:277-80. [PMID: 389662 DOI: 10.1016/0014-5793(79)80389-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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