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Analytical Biochemistry May 1977
Topics: Animals; Cattle; Dianisidine; Erythrocytes; Horseradish Peroxidase; Humans; Hydrogen-Ion Concentration; Liver; Methods; Peroxides; Spectrophotometry; Superoxide Dismutase; Xanthine Oxidase
PubMed: 17332
DOI: 10.1016/0003-2697(77)90429-8 -
Biokhimiia (Moscow, Russia) Dec 1980The individual and combined oxidation of 5-mercapto-1,3,4-thiadiazolthione-2 (bismuthol I) and 3,3'-dimethoxybenzidine (o-dianisidine) by hydrogen peroxide catalyzed by...
The individual and combined oxidation of 5-mercapto-1,3,4-thiadiazolthione-2 (bismuthol I) and 3,3'-dimethoxybenzidine (o-dianisidine) by hydrogen peroxide catalyzed by horseradish peroxidase (pH 5,0) was studied. It was shown that bismuthol I is a substrate for peroxidase, which is competitive towards o-dianisidine. In the presence of bismuthol I the Km value for o-dianisidine is increased, while kappa cat remains unchanged. The competitive inhibition constant for bismuthol is equal to 19,4 mkM. An addition of bismuthol I causes the appearance of the induction period (tau) on the kinetic curves of o-dianisidine oxidation, whose duration is proportional to bismuthol concentration. The kinetic patterns allowing interpretation of the experimental results are proposed. A kinetic analysis permitted to determine the rate constants for the individual steps of omicron-dianisidine oxidation catalyzed by peroxidase.
Topics: Benzidines; Dianisidine; Horseradish Peroxidase; Hydrogen Peroxide; Kinetics; Mathematics; Peroxidases; Substrate Specificity; Thiadiazoles
PubMed: 7248354
DOI: No ID Found -
Parasitology Jan 1997Oocysts of Cryptosporidium parvum showed relatively low levels of SOD activity. The SOD which had a pI of 4.8 and an approximate molecular weight of 35 kDa appeared to...
Oocysts of Cryptosporidium parvum showed relatively low levels of SOD activity. The SOD which had a pI of 4.8 and an approximate molecular weight of 35 kDa appeared to be iron dependent. Catalase, glutathione transferase, glutathione reductase and glutathione peroxidase activity could not be detected, nor could trypanothione reductase. No NADH or NADPH oxidase activity could be detected, nor could peroxidase activity be demonstrated using o-dianisidine, guaiacol, NADPH or NADH as co-substrates. However, an NADPH-dependent H2O2 scavenging system was detected in the insoluble fraction.
Topics: Animals; Catalase; Cattle; Cryptosporidiosis; Cryptosporidium parvum; Feces; Glutathione Peroxidase; Glutathione Reductase; Glutathione Transferase; Isoelectric Point; Molecular Weight; NADH, NADPH Oxidoreductases; Peroxidases; Superoxide Dismutase
PubMed: 9011070
DOI: 10.1017/s0031182096008037 -
Biochemical and Biophysical Research... Oct 1998Iron-chelating low-molecular-weight compounds or catecholate siderophores have been suggested to be involved in wood biodegradation. To help in understanding the...
Iron-chelating low-molecular-weight compounds or catecholate siderophores have been suggested to be involved in wood biodegradation. To help in understanding the mechanism involved in the enzyme-like activity of catecholate siderophores, the oxidative properties of 2,3-dihydroxybenzoic acid (DHBA) and 3, 4-dihydroxyphenylacetic acid (DHPAA) chelated with iron were studied. The pH and catechol/Fe(III) ratios were optimized for o-dianisidine oxidation, obtaining a maximum at pH 7.0, in the absence of buffer, and a catechol/Fe(III) ratio of 1:2 to DHBA and 1:1 to DHPAA was found. Under these conditions, the catechols were able to reduce Fe(III) to Fe(II) acting like siderophore models. The Fe(III) complex of DHBA and of DHPAA degraded dioxane-lignin in 60% after 2 h and 85% after 24 h, respectively. DHBA/Fe(III) oxidized the bleaching effluent (E1) in 80% in 5 min under the studied conditions.
Topics: 3,4-Dihydroxyphenylacetic Acid; Dioxanes; Hydroxybenzoates; Iron; Iron Chelating Agents; Kinetics; Lignin; Oxidation-Reduction; Spectrometry, Fluorescence; Spectrophotometry
PubMed: 9792786
DOI: 10.1006/bbrc.1998.9315 -
Clinical Chemistry Dec 1974
Comparative Study
Topics: Aniline Compounds; Anisoles; Biphenyl Compounds; Ceruloplasmin; Colorimetry; Evaluation Studies as Topic; Humans; Hydrogen Peroxide; Indicators and Reagents; Mathematics; Methods; Oxidation-Reduction; Spectrophotometry; Spectrophotometry, Ultraviolet
PubMed: 4430134
DOI: No ID Found -
Archives of Biochemistry and Biophysics May 1977
Topics: Benzidines; Dianisidine; Hydrogen-Ion Concentration; Light; Models, Chemical; Oxidation-Reduction; Riboflavin; Spectrophotometry; Superoxide Dismutase
PubMed: 18108
DOI: 10.1016/0003-9861(77)90509-4 -
Analytical Sciences : the International... Jan 2022The aim of this work was the development of an automatic sequential injection analysis method to monitor the ozonation process for water disinfection. The determination...
The aim of this work was the development of an automatic sequential injection analysis method to monitor the ozonation process for water disinfection. The determination was based on the reaction between bromate and o-dianisidine in the presence of bromide in acidic medium. The determination parameters were studied and adjusted to enable bromate quantification in the range 0.35-4.0 mg BrO/L with a limit of detection of 20 μg BrO/L. The choice of a sequential injection procedure enabled a minimal consumption of reagents and no need for sample pre-treatment. The developed sequential injection proved to be accurate with < 5% relative deviation when compared to ICP-MS and an average of 101% in recovery percentages studies. It was effectively applied to monitor an ozonation process enabling the follow-up of the process with real-time quantification of the bromate content.
Topics: Bromates; Disinfection; Ozone; Water; Water Supply
PubMed: 35287215
DOI: 10.2116/analsci.21P191 -
Biokhimiia (Moscow, Russia) Aug 1977A kinetic study of o-dianisidine oxidation by hydrogen peroxide in the presence of horseradish peroxidase within the pH range of 3.7-9.0 has been carried out. It was...
A kinetic study of o-dianisidine oxidation by hydrogen peroxide in the presence of horseradish peroxidase within the pH range of 3.7-9.0 has been carried out. It was shown that the reaction of o-dianisidine peroxidase oxidation obeys the Michaelis--Menten kinetics; the kcat and Km values within the pH range used were determined. The optimum of peroxidase catalytic activity during o-dianisidine oxidation was observed at pH 5.0-6.0. The kinetic pattern of the reaction is discussed. It was demonstrated that deprotonation of the group at pK 6.5 decreases the kcat value 60 times. At pH greater than 8.0 an additional ionogenic group controls the enzyme activity.
Topics: Benzidines; Dianisidine; Horseradish Peroxidase; Hydrogen Peroxide; Hydrogen-Ion Concentration; Kinetics; Oxidation-Reduction; Peroxidases; Protons
PubMed: 20989
DOI: No ID Found -
Biochemical and Biophysical Research... Feb 1999P. S. Alban et al. (J. Appl. Microbiol. (1998) 85, 875-882) reported that a mutant H2O2-resistant strain of Spirullum (S.) volutans showed constitutive overexpression of...
P. S. Alban et al. (J. Appl. Microbiol. (1998) 85, 875-882) reported that a mutant H2O2-resistant strain of Spirullum (S.) volutans showed constitutive overexpression of a protein whose amino acid sequence and molecular weight closely resembled that of a subunit of rubrerythrin, a non-heme iron protein with no known function. They also reported that the mutant strain, but not the wild-type, showed NADH peroxidase activity. Here we demonstrate that rubrerythrin and nigerythrin from Desulfovibrio vulgaris and rubrerythrin from Clostridium perfringens show NADH peroxidase activities in an in vitro system containing NADH, hydrogen peroxide, and a bacterial NADH oxidoreductase. The peroxidase specific activities of the rubrerythrins with the "classical" heme peroxidase substrate, o-dianisidine, are many orders of magnitude lower than that of horseradish peroxidase. These results are consistent with the phenotype of the H2O2-resistant strain of S. volutans. The reaction of reduced (i.e., all-ferrous) rubrerythrin with excess O2 takes several minutes, whereas the anaerobic reaction of reduced rubrerythrin with hydrogen peroxide is on the millisecond time scale and results in full oxidation of all iron centers to their ferric states. Rubrerythrins could, thus, function as the terminal components of NADH peroxidases in air-sensitive bacteria and archaea.
Topics: Bacterial Proteins; Desulfovibrio vulgaris; Enzyme Activation; Ferredoxins; Hemerythrin; Hydrogen Peroxide; NAD; Oxidation-Reduction; Oxidoreductases; Oxygen; Peroxidases; Rubredoxins; Superoxide Dismutase
PubMed: 10049706
DOI: 10.1006/bbrc.1999.0197 -
Biochimica Et Biophysica Acta. General... Jul 2018A number of compounds, including ascorbic acid, catecholamines, flavonoids, p-diphenols and hydrazine derivatives have been reported to interfere with peroxidase-based... (Comparative Study)
Comparative Study
BACKGROUND
A number of compounds, including ascorbic acid, catecholamines, flavonoids, p-diphenols and hydrazine derivatives have been reported to interfere with peroxidase-based medical diagnostic tests (Trinder reaction) but the mechanisms of these effects have not been fully elucidated.
METHODS
Reactions of bovine myeloperoxidase with o-dianisidine, bovine lactoperoxidase with ABTS and horseradish peroxidase with 4-aminoantipyrine/phenol in the presence of carbidopa, an anti-Parkinsonian drug, and other catechols, including l-dopa, were monitored spectrophotometrically and by measuring hydrogen peroxide consumption.
RESULTS
Chromophore formation in all three enzyme/substrate systems was blocked in the presence of carbidopa and other catechols. However, the rates of hydrogen peroxide consumption were not much affected. Irreversible enzyme inhibition was also insignificant.
CONCLUSIONS
Tested compounds reduced the oxidation products or intermediates of model substrates thus preventing chromophore formation. This interference may affect interpretation of results of diagnostic tests in samples from patients with Parkinson's disease treated with carbidopa and l-dopa.
GENERAL SIGNIFICANCE
This mechanism allows prediction of interference in peroxidase-based diagnostic tests for other compounds, including drugs and natural products.
Topics: Animals; Carbidopa; Catalysis; Catechols; Cattle; Chromogenic Compounds; Horseradish Peroxidase; Humans; Hydrogen Peroxide; Lactoperoxidase; Molecular Docking Simulation; Molecular Structure; Monophenol Monooxygenase; Oxidation-Reduction; Peroxidase; Peroxidases
PubMed: 29649511
DOI: 10.1016/j.bbagen.2018.04.007