76
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Dmitriev DA, Massino IS, Smirnova MB, Segal OL, Pavlova EB, Koliaskina GI, Osipov AP, Egorov AM, Dmitriev AD. [The binding of bispecific monoclonal antibodies to the solid phase-adsorbed antigens]. BIOORGANICHESKAIA KHIMIIA 2001; 27:265-74. [PMID: 11558260 DOI: 10.1023/a:1011352419668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The ability of bispecific antibodies (Babs) formed by fusion of hybridomas and parent monoclonal antibodies (Mabs) to interact with the solid phase-adsorbed antigens was studied. Mabs specific to the three different antigens [horseradish peroxidase (HRP), human IgG (hIgG), and human myoglobin (Mb)] as well as Babs with the double specificity [antimyoglobin/antiperoxidase (anti-Mb/HRP) and anti-hIgG/antiperoxidase (anti-hIgG/HRP)] were used. It was shown by radioimmunological and immunoenzyme assays that parent Mabs bind to solid phase-adsorbed antigens considerably more effectively than Babs. The observed equilibrium binding constant (Ka) of antiperoxidase parental Mabs to immobilized HRP is 21 and 38 times higher than Ka for Babs binding sites (anti-Mb/HRP and anti-hIgG/HRP, respectively) to peroxidase. It was calculated that about 90-95% of all bound parental antiperoxidase Mabs were associated with immobilized HRP bivalently, and only about 5-10% were bound monovalently. On the contrary, parental Mabs against hIgG bind to the sorbed antigen essentially only monovalently. It was also shown that the avidity of anti-Mb/HRP Babs significantly increased when two antigens, Mb and HRP, were simultaneously adsorbed on the solid phase. These data imply that Babs bearing an enzyme-binding site (for example, binding to HRP) cannot be more effective than standard conjugates (e.g., enzyme-conjugated antibodies) in heterogeneous noncompetitive immunoassays.
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77
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Egorov AM, Sazykin IO. [Cephalosporin antibiotics: the first ones by their significance and complexity of their discovery]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2001; 46:3-6. [PMID: 11221082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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78
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Ferapontova EE, Grigorenko VG, Egorov AM, Börchers T, Ruzgas T, Gorton L. Mediatorless biosensor for H(2)O(2) based on recombinant forms of horseradish peroxidase directly adsorbed on polycrystalline gold. Biosens Bioelectron 2001; 16:147-57. [PMID: 11339993 DOI: 10.1016/s0956-5663(01)00134-8] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Four forms of horseradish peroxidase (HRP) have been used to prepare peroxidase-modified gold electrodes for mediatorless detection of peroxide: native HRP, wild type recombinant HRP, and two recombinant forms containing six-His tag at the C-terminus and at the N-terminus, respectively. The adsorption of the enzyme molecules on gold was studied by direct mass measurements with electrochemical quartz crystal microbalance. All the forms of HRP formed a monolayer coverage of the enzyme on the gold surface. However, only gold electrodes with adsorbed recombinant HRP forms exhibited high and stable current response to H(2)O(2) due to its bioelectrocatalytic reduction based on direct electron transfer between gold and HRP. The sensitivity of the gold electrodes modified with recombinant HRPs was in the range of 1.4-1.5 A M(-1) cm(-2) at -50 mV versus Agmid R:AgCl. The response to H(2)O(2) in the concentration range 0.1-40 microM was not dependent on the presence of a mediator (i.e. catechol) giving strong evidence that the electrode currents are diffusion limited. Lower detection limit for H(2)O(2) detection was 10 nM at the electrodes modified with recombinant HRPs.
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79
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Egorov AM, Sazykin IO. [Discussions on problems in chemotherapy at the VII National Russian Congress "Man and Drug"]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2001; 45:9-11. [PMID: 11212496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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80
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Egorov AM, Sazykin IO. [Fluoroquinolones and problems of molecular mechanism of their action]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2001; 45:3-5. [PMID: 10989716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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81
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Egorov AM. [The achievements of the fundamental sciences and new approaches in the chemotherapy of tuberculosis]. PROBLEMY TUBERKULEZA 2001:11-5. [PMID: 11077844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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82
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Egorov AM, Sazykin IO. [Antibiotics and problems of pharmacoenzymology]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2001; 45:3-6. [PMID: 11057366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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83
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Karyakin AA, Presnova GV, Rubtsova MY, Egorov AM. Oriented immobilization of antibodies onto the gold surfaces via their native thiol groups. Anal Chem 2000; 72:3805-11. [PMID: 10959966 DOI: 10.1021/ac9907890] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The general approach for site-oriented immobilization of antibodies onto gold supports is reported. The immobilization is carried out using the native sulfide groups of immunoglobulin (IgG). To liberate the thiol groups, the intact IgG was split into two half-IgG fragments without destruction of the binding site of the antibody. The immobilization of half-IgG fragments on the gold surface was carried out by simple adsorption. The antigen binding capacity of the half-IgG modified gold supports is similar to that of the gold surfaces with the traditionally linked antibodies and is much higher than for nonspecifically adsorbed intact IgGs. The immobilized antibodies, according to the proposed approach, maintain high antigen binding constants. The immobilization procedure provides orientation of IgG fragments in terms of the similar distance between the binding site of the antibody and the surface of the gold support, which does not cause the distribution of the apparent affinity constants. The high operational stability of half-IgG modified gold electrodes makes them applicable for analytical applications.
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84
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Egorov AM, Sazykin IO. [Chlamydia. The molecular organization of the cell and the pathogenetic characteristics of infections]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2000; 45:3-5. [PMID: 10851641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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85
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Gogichaeva NV, Lukasheva EV, Gavrilova EM, Smirnova IP, Egorov AM, Berezov TT. [Synthesis of conjugates of L-lysine alpha-oxidase with antibodies]. VOPROSY MEDITSINSKOI KHIMII 2000; 46:410-8. [PMID: 11075424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
The conjugation of the drugs with vector molecules enables to obtain therapeutic preparation, which may be transported to the selected target organ. In the present work the methods of conjugation of antineoplastic enzyme L-lysine alpha-oxidase with antibodies were elaborated. Conjugates were worked out through the attachment of amino groups on the antibody surface either with the aldehyde groups which were created in L-lysine alpha-oxidase molecule (0.2% of initial enzymatic activity) or with the aldehyde groups of cross-linking molecules. Maximal (78%) L-lysine alpha-oxidase activity in conjugates was observed when oxidized peroxidase which contained the aldehyde groups was used as crosslinking agent. The glutaraldehyde method yielded 70% of initial enzyme activity.
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86
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Egorov AM, Sazykin IO. [Antimicrobial agents in the future. The contribution of genomics to their design]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2000; 44:5-14. [PMID: 10687027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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87
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Egorov AM, Sazykin IO. [Pathogen microevolution in the course of an infectious process]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2000; 45:3-4. [PMID: 10690420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
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88
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Egorov AM, Sazykin IO. [The problems in the chemotherapy of tuberculosis taking into account new data on its causative organism]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 2000; 45:3-5. [PMID: 10862346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
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89
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Kolosova AI, Samsonova ZV, Egorov AM, Shevaleva SA, Orlova NG, Kiseleva TV, Khotimchenko SA, Tutel'ian VA. [Optimization of a method of solid-phase immunoenzyme analysis for determination of chloramphenicol in milk]. Vopr Pitan 1999; 68:23-7. [PMID: 10198960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The method of solid-phase enzyme linked immunosorbent assay (ELISA) for quantitative detection of chloramphenicol (CAP) in milk was developed. Peculiarities of the adsorption on the microtitre plates surface of CAP-ovalbumin conjugate were investigated. Different conditions of competition stage of the analysis were studied. Conditions providing CAP monitoring in human blood serum in the clinical range were optimized. Matrix effect on the assay results was studied. The specificity of the analytical system was investigated and the reagents stability was examined. The method developed permits CAP concentration to be determined in human blood serum, diluted 1/100, in the linear range from 0.1 to 100 ng/ml. The assay is characterized by high sensitivity (0.08 ng/ml) and good reproducibility (CV < 10.8%), assay time is about 3 hours. The correlation coefficient with HPLC is 0.977.
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90
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Samsonova JV, Kiseleva AV, Ezhov AA, Egorov AM. Chemiluminescent multiassay of pesticides with horseradish peroxidase as a label. Biosens Bioelectron 1999; 14:273-81. [PMID: 10230027 DOI: 10.1016/s0956-5663(98)00129-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Competitive chemiluminescent immunoassay based on a combination of five antibodies was used in a combination with neural network to identify and estimate amounts of three cross-reacting s-triazines (atrazine, terbythylazine and ametryn). Antibodies with different cross-reactivity towards s-triazines were immobilized in separate wells an eight-well microtiter strip. Training of neural networks was carried out with four different learning procedures. The best topology for the data measured was a net with two hidden layers with ten neurons in the first and 15 in the second layer trained with the Schmidhuber method. s-Triazine classification of environmental samples containing various analyte mixtures was correct in 70-100% of all cases depending on the type of analyte. The test developed can be proposed as an alternative field test for multianalyte environmental monitoring.
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91
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Egorov AM, Anisimov AV, Tarakanova AV. Low-temperature dehalogenation of benzyl halides with atomic magnesium in the3P state. Russ Chem Bull 1999. [DOI: 10.1007/bf02494417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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92
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Ptitsyn LR, Kotel'nikov MA, Spiridonova VA, Kopylov AM, Egorov AM. [Selection of thyroxin-binding oligodeoxyribonucleotides]. DOKLADY AKADEMII NAUK 1999; 364:260-3. [PMID: 10188085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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93
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Kolosova AY, Blintsov AN, Samsonova JV, Egorov AM. Development of an enzyme-linked immunosorbent assay for gentamicin in human blood serum. ACTA ACUST UNITED AC 1998. [DOI: 10.1007/s002160050896] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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94
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Kolosova AI, Blintsov AN, Samsonova ZV, Egorov AM. [Development of a solid-phase immunoenzyme analysis of gentamicin in human blood serum]. ANTIBIOTIKI I KHIMIOTERAPIIA = ANTIBIOTICS AND CHEMOTERAPY [SIC] 1998; 43:9-13. [PMID: 9551167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
An enzyme immune test system was designed and optimized for quantitative assay of gentamicin in human sera. Immunospecific reagents i.e. gentamicin conjugates with ovalbumin (for sorption on polysterol plates) and with bovine serum albumin (immunogen) were prepared. Gentamicin specific antisera were isolated and tested. Conditions for the antigen sorption on polysterol plates were determined and optimized. Different regimes of the competition reaction were investigated and conditions for the antibiotic assay in human sera were determined. The assay specificity was studied and the stability of the test system was checked. An experimental lot of the reagent set was manufactured at the ZAO NPP Immunotech and the correlation tests with the use of the fluorescence polarization immunoassay were performed. The set is destined for the assay of 40 samples (in duplicate). The method sensitivity is 1 ng/ml of gentamicin. The range of the detectable concentration is 1 to 32 ng/ml of gentamicin in 1000-fold diluted sera. The assay time is not more than 3 hours. The variation coefficient of the results does not exceed 12 per cent. The shelf-life of the set is 0.5 years when stored at a temperature of 2 to 8 degrees C.
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95
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Kolosova AI, Samsonova ZV, Blintsov AN, Egorov AM. [Solid-phase immunoenzyme analysis of chloramphenicol in human blood serum]. VOPROSY MEDITSINSKOI KHIMII 1998; 44:194-202. [PMID: 9634723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The method of enzyme linked immunosorbent assay (ELISA) for quantitative detection of chloramphenicol (CAP) in human blood serum was developed. Peculiarities of the adsorption on the microtitre plates surface of CAP-ovalbumin conjugate were investigated. Different conditions of competition stage of the analysis were studied. Conditions providing CAP monitoring in human blood serum in the clinical range were optimized. Matrix effect on the assay results was studied. The specificity of the analytical system was investigated and the reagents stability was examined. The method developed permits CAP concentration to be determined in human blood serum, diluted 1/100, in the linear range from 10 to 1000 ng/ml. The assay is characterized by high sensitivity (1 ng/mL) and good reproducibility (CV < 12%), assay time is about 3 hours.
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96
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Kovba GV, Egorov AM. Chemiluminescent biosensors based on porous supports with immobilized peroxidase. Biosens Bioelectron 1998; 13:75-85. [PMID: 9519452 DOI: 10.1016/s0956-5663(97)00072-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Combining a sensitive and fast chemiluminescence detection method with novel immobilization methods for horseradish peroxidase (HRP) has enabled us to develop sensitive sensors for hydrogen peroxide and the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). HRP biospecific immobilization was shown to have well-defined advantages in terms of a higher specific activity of the enzyme of the surface and a greater sensitivity in the enhanced chemiluminescence (ECL) reaction. The lower detection limit for hydrogen peroxide was 0.025 nmol with HRP immobilized on nitrocellulose membrane through avidin-biotin linkage. An immunosensor for the detection of 2,4-D provides a lower detection limit of 0.2 microgram/l with specific antibodies covalently immobilized on photoactivated nylon. The assay with chemiluminescent detection was also characterized with a wider concentration range when compared with the colorimetric assay.
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97
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Kapeluich YL, Egorov AM. Enhanced chemiluminescence reaction applied to the study of horseradish peroxidase stability in the course of p-iodophenol oxidation. JOURNAL OF BIOLUMINESCENCE AND CHEMILUMINESCENCE 1997; 12:299-308. [PMID: 9509338 DOI: 10.1002/(sici)1099-1271(199711/12)12:6<299::aid-bio459>3.0.co;2-s] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The enhanced chemiluminescence reaction (ECL) was applied to the study of horseradish peroxidase (HRP) inactivation during the oxidation of p-iodophenol. Enzyme inactivation was shown to be the main reason for light decay in the course of the reaction. No individual effect of luminol and p-iodophenol as enhancer on HRP activity towards 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) was detected, enzymatic activity loss was detected only in the course of the ECL reaction. HRP activity towards ABTS (a colorimetric substrate) fell in a similar manner to the decay in light emission. The reactive radical species formed during enhancer oxidation were suggested as the main inactivating agents. The similarity of changes in light intensity and enzymatic activity allows one to apply the ECL reaction for testing potential stabilizers of HRP. The loss of enzyme activity can be partially explained by non-specific interaction of radical species with protein globule. The addition of bovine serum albumin provided almost complete protection of peroxidase from inactivation. This confirms the non-specific inactivation with highly reactive endogenous intermediates through the modification of a protein globule.
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98
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Lukasheva EV, Rubtsova MI, Kovba GV, Berezov TT, Egorov AM. [Joint immobilization of L-lysine-alpha-oxidase and peroxidase on porous membrane carriers]. VOPROSY MEDITSINSKOI KHIMII 1997; 43:566-75. [PMID: 9503574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The goal of the present study was the development of the optimal method of co-immobilization of two enzymes: L-lysine alpha-oxidase from Trichoderma sp. and horseradish peroxidase. Commercial nitrocellulose, nylon and N+ nylon membranes were used as carriers. The immobilization was carried out either by absorbtion or by covalent binding with aldehyde groups. The aldehyde groups were attached to the surface of the carriers by UV-irradiation of membranes in the presence of p-azidotetrafluorobenzaldehyde. The optimal concentrations of reagents, enzymes and reaction conditions were found. The membranes with the co-immobilised L-lysine alpha-oxidase and peroxidase were shown to be useful for the determination of L-lysine concentrations.
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99
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Uporov IV, Egorov AM. [Modeling the spatial structure of horseradish peroxidase (isoenzyme C)]. DOKLADY AKADEMII NAUK 1997; 356:696-9. [PMID: 9424181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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100
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Ammosova TN, Ouporov IV, Ignatenko OV, Egorov AM, Kolesanova EF, Archakov AI. Epitope mapping of horseradish peroxidase (isoenzyme C). BIOCHEMISTRY. BIOKHIMIIA 1997; 62:440-7. [PMID: 9275282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Peptide scanning (PEPSCAN) was used to determine linear antigenic determinants of horseradish peroxidase isoenzyme C (HRPC). For this purpose, we synthesized 303 overlapping hexapeptide fragments (with a step of one amino acid residue) of the protein primary structure and studied their interactions with anti-HRPC polyclonal antisera by ELISA. Experiments with various titers of antisera allowed us to determine linear antigenic determinants of HRPC; several such determinants were spatially located in regular elements of the secondary structure (alpha-helices) found both inside and outside the protein globule. A fraction of epitopes were located in loops and folds of the HRPC peptide chain with irregular shapes. These epitopes contained several functionally important residues: Arg 38, which is part of the active site of the enzyme, as well as Phe 142 and Phe 143, which form a channel allowing aromatic substrates to reach the active site. Amino acid residues that form calcium-binding sites or occur in the vicinity of disulfide bonds are not involved in these epitopes.
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