Two novel FRET-pairs: Tb3+ -binding peptide-DsRed2 and Tb3+ -binding peptide-TagRFP have been produced based on the terbium-binding peptide and the red fluorescent proteins DsRed2 and TagRFP. Two induction-resonance energy transfer processes in both FRET-pairs have been registered, from tryptophan of the terbium-binding peptide to Tb3+ and from sensitized Tb3+ to the acceptor, the chromophore, DsRed2 or TagRFP. The lifetimes of terbium in the presence and absence of the acceptor have been determined.
View Article and Find Full Text PDFThe genetically encoded FRET-pair was developed on the basis of terbium-binding peptide and red fluorescent protein DsRed2. To study fluorescence resonance energy transfer within FRET-pair, the gene-engineered construction was obtained, where sequences of terbium-binding peptide and red fluorescent protein DsRed2 were fused in single reading frame. The expression of this construction in strain E.
View Article and Find Full Text PDFClinical case of Crohn's disease diagnostics with psoriatic appearance of skin rash as the first manifestation described.
View Article and Find Full Text PDFThe determination of thyroxin (T4) is a basic confirmative test for congenital hypothyroidism. 70% cases of this period inborn disease are taking asymptomatic course. We developed immunofluorescent T4-assay in dried blood spots with anti-T4 monoclonal antibody and europium chelate (dianhydride of diethylentriaminipentaacetic acid (DA-DTPA)).
View Article and Find Full Text PDFThe analysis of the content of radionuclides 90Sr, 137Cs, 238Pu, 239 + 240Pu and 241Am in water vegetation of flood plain reservoirs has allowed studing features of radionuclide accumulation by various species of macrophytes and revealing bioindicators of radionuclide contamination. Thus species-specificity of radionuclide accumulation can essentially change the contribution of different species to a percentage ratio of the radionuclide content in phytomass of reservoirs in comparison with fund of higher aquatic plants.
View Article and Find Full Text PDFSite-directed mutagenesis was used to study the structural basis of color diversity of fluorescent proteins by the example of two closely related proteins from one organism (coral polyp Zoanthus sp.), one of which produces green and the other, yellow fluorescence. As a result, the following conversions of emission colors were performed: from yellow to green, from yellow to a dual color (yellow and green), and from green to yellow.
View Article and Find Full Text PDFFluorescence of luciferases from Luciola mingrelica (single tryptophan residue, Trp-419) and Photinus pyralis (two tryptophan residues, Trp-417, Trp-426) was studied. Analysis of quenching of tryptophan fluorescence showed that the tryptophan residue conserved in all luciferases is not accessible for charged quenchers, which is explained by the presence of positively and negatively charged amino acid residues in the close vicinity to it. An effective energy transfer from tryptophan to luciferin was observed during quenching of tryptophan fluorescence of both luciferases with luciferin.
View Article and Find Full Text PDFQuenching of tryptophan fluorescence of Luciola mingrelica (single tryptophan residue, Trp-419) and Photinus pyralis (two tryptophan residues, Trp-417 and Trp-426) luciferases with different quenchers (I-, Cs+, acrylamide) was studied. The conserved Trp-417(419) residue was shown to be not accessible to charged particles, and positively and negatively charged amino acid residues are located in close vicinity to it. We found previously unreported effective energy transfer from this tryptophan to luciferin during the quenching of the tryptophan fluorescence.
View Article and Find Full Text PDFThe next revolution in in-vitro bioaffinity assays will be associated with the minimization of the liquid phase of an experiment and with the extremely rapid detection of a large number of samples. The ultra detection unit is one of the essential elements of such devices. The fluorescence detection systems are most promising.
View Article and Find Full Text PDFA solid-phase enzyme immunoassay procedure for detecting natural antibodies to vasopressin (VP) is developed. For this purpose, a VP antigen is synthesized on polymer matrix. Optimal conditions of enzyme immunoassay for detecting antibodies to this antigen in the sera of donors and patients with systemic lupus erythematosus (SLE) are selected.
View Article and Find Full Text PDFConjugates of cobalt and aluminum phthalocyanines with monoclonal antibodies were synthesized using an AOT/n-octane reversed micellar system or water-organic mixtures with a low content of organic solvent as media. The effect of the degree of hydration of the micelles and the concentration of phthalocyanines on the composition of conjugates was studied. The immune activity of the resulting conjugates in comparison to that of native antibodies was evaluated.
View Article and Find Full Text PDFDigitoxin at concentrations up to 5 x 10(-10) M (therapeutic concentrations are 2 x 10(-8) M) can be reliable measured by a fluoroimmunometric method with coproporphyrin as a tracer. The use of nylon filters with immobilized digitoxin to remove an excess of labelled antibodies increases reliability and reduces the time of measurements, and thus simplifies the assay.
View Article and Find Full Text PDFA flow-injection method for the determination of glucose in serum is presented. It is based on the enzymatic measurement of oxygen consumption detected via oxygen quenching of the luminescence of certain metalloporphyrins. Phosphorescent water-soluble Pt2+ and Pd(2+)-porphyrins have been characterized by luminescence spectroscopy and decay-time measurements in various buffers, and found to be suitable for oxygen detection in biological systems.
View Article and Find Full Text PDFA fibre-optic oxygen sensor is described which is based on an oxygen-sensitive luminescent film made from platinum octaethylporphyrin and polystyrene. The luminescence and quenching characteristics of such films were studied for their use in a fibre-optic oxygen biosensor. A prototype oxygen sensor was made from this material, and was tested in aqueous solutions and in the gaseous phase at physiological oxygen concentrations.
View Article and Find Full Text PDFThe effective photogeneration of singlet molecular oxygen (1O2) by porphyrins (coproporphyrin I; 2,4-bi (alpha-methoxyethyl) deuteroporphyrin IX and cyclopanten-coproporphyrin I) conjugated with antibodies (mouse monoclonal IgG and IgM and human gamma-globulin) have been observed with the direct luminescence method of 1O2 detection. Absolute quantum yields of 1O2 formation by the conjugates have been determined. The data suggest that porphyrin-antibody conjugates are promising for the use as drugs in photodynamic tumor treatment.
View Article and Find Full Text PDFThe photodynamic action of a number of carboxylic porphyrins and their covalent conjugates with specific monoclonal IgM antibodies on a human lung adenocarcinoma cell line was studied. All the conjugates showed strong phototoxicity which did not correspond with the phototoxicity of the free porphyrins. Absolute quantum yields of singlet oxygen photogeneration by the porphyrins and their conjugates were obtained and compared with the phototoxicity of the compounds.
View Article and Find Full Text PDFMonoclonal antibodies, epidemic strains of influenza A and B viruses, conjugates were studied by fluorescence immunoassay with temporary resolution using equipment of different companies. Differences and specificity of monoclonal antibodies to influenza A and B viruses were demonstrated. The highest sensitivity of the method with the test system used was determined, being 20 ng/ml of viral protein.
View Article and Find Full Text PDFThe 34-mer oligodeoxynucleotide was shown to be selectively modified at the G17 position upon photoirradiation in the presence of complementary 17-mer oligodeoxynucleotide bearing Pd(II)-coproporphyrin I covalently linked to the 5'-end phosphate group.
View Article and Find Full Text PDFPrikl Biokhim Mikrobiol
January 1990
The chromatographic behaviour of tetra- and octacarboxylic porphyrins and tetra-(p-sulphophenyl)-porphin was being studied by HPLC using Protein Pak and TSK-type gel permeation columns. The mobility of the porphyrins on the carriers depended on the ionic strength of the eluating buffer Tris-HCl. The conditions for separation of the porphyrins and their protein conjugates were optimized.
View Article and Find Full Text PDFThe synthesis of protein conjugates with the new high-efficient fluorescent labile coproporphyrin-I was optimized. A number of conjugates of monoclonal antibodies with different coproporphyrin-I content were synthesized, and their spectral properties were studied in water and micellar solutions, i.e.
View Article and Find Full Text PDFRecently developed solid-phase immunofluorescent assay with temporal distinction involved a newly produced procedure for binding of of the boron group label with antibodies via modified polymer, which is able to bind with antibodies across the avidin bridge. The assay developed is more simple than the widely used procedures, it exhibits high sensitivity being superior as compared with a corresponding immunoenzyme assay by a decimal order.
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