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At least 811 records · Page 45Linked to original sources
PubMed2003

Human liver catalase: cloning, expression and characterization of monoclonal antibodies.

We isolated a cDNA encoding liver catalase from a human liver cDNA library. The cDNA had a high degree of sequence similarity to the corresponding enzyme from other sources. It was expressed in E. coli using the pET15b vector. The protein produced was enzymatically active after purification, and its kinetic parameters closely resembled those of other mammalian catalases. Monoclonal antibodies were generated against the purified catalase; six antibodies recognizing different epitopes were obtained, one of which inhibited the enzyme. The cross reactions of the antibodies with brain catalases from human and other mammalian tissues were investigated, and all the immunoreactive bands obtained on Western blots had molecular masses of about 58 kDa. Similarly fractionated extracts of several mammalian cell lines all gave a single band of molecular mass 58 kDa. These results indicate that mammalian livers and human cell lines contain only one major type of immunologically reactive catalase, even though some of catalases have been previously reported to differ in certain properties.

Amino Acid Sequence↗
PubMedDate not supplied

[pH-dependency of Escherichia coli catalase activity under modified culture conditions].

In the previous work we have found two peaks of catalase activity at acid and neutral pH in partially destroyed bacteria E. coli K12 KS400. The present study indicates that catalase activity with two pH-optimums is sensitive to pH of cultivation medium. The relative catalase activity of frozen-thawed bacteria preparations measured at pH 3.5 increased two-fold and activity measured at pH 7.0 didn't change by shift of medium pH from value 5.5 to 7.0. In analogical preparations of bacteria grown in slightly alkaline media activity with acid maximum was not observed, but activity with neutral maximum rose to 130% in comparison with the intact cells was revealed. Two peaks of activity differed in their sensitivity to bacteria destruction, heating, inhibition by NaN3 and AMT, oxidative stress. The analysis of recent literature information and experimental data leads us to conclude that the activity with neutral pH-optimum consists of two known catalase forms HPI and HPII in E. coli. The ratio of HPI and HPII is 70 and 30%, respectively what was concluded from inhibition of catalase activity with neutral pH-optimum by AMT. Properties of catalase activity with acid pH-optimum didn't corresponding to any known enzyme forms. It is suggested the activity measured at pH 3.5 is results of some unstable activator which acts in acid pH range. It is possible that the described activity with acid pH-optimum is specific for the used E. coli strain. Investigation of another strain of E. coli K12 AB1157 confirmed this idea where the activity peak with acid pH-optimum was not detected.

Catalase↗
PubMed2005

[Simultaneous purification of superoxide dismutase, catalase and hemoglobin from bovine erythrocyte lysate with PEG 600 as chaperon].

Superoxide dismutase, catalase and hemoglobin were purified simultaneously from the same batch of bovine erythrocyte lysate. The process involves an initial anion exchange chromatography, followed by a hydrophobic interaction chromatography and gel filtration chromatography. 0.75% polyethylene glycol 600 was added as a purification chaperon before the anion exchange chromatography. The hemoglobin fraction passed through the ion exchange column without being retained. The superoxide dismutase and catalase were adsorbed by the column and were eluted separately during elution. The two eluted fractions containing crude superboxide dismutase and catalase were further purified with hydrophobic interaction chromatography and gel filtration chromatography in sequence. The specific activities of superoxide dismutase and catalase were 15932u/mg and 65918u/mg, respectively. SDS-polyacrylamide gel electrophoresis and gel filtration chromatography were used to analyze the purity of the proteins. The purity of superoxide dismutase, catalase and hemoglobin were 77.6%, 81.9% and 99.9%, respectively. The total recoveries for superoxide dismutase, catalase and hemoglobin were 47.4%, 29.6% and 88.7%, respectively.

Animals↗
PubMed1992

Extraction and purification of a catalase from Candida albicans.

Candida albicans yeast cells H317 were grown to mid-log phase, mechanically disrupted and the resulting crude extract clarified by centrifugation. This catalase rich fraction (1.26 x 10(-4) units/ml) was fractionated by liquid phase isoelectric focusing in a pH gradient ranging from 3 to 10 using the Rotofor Isoelectric Focusing Preparative Cell. After isoelectric separation, fractions containing catalase activity were focused between pH 6.7 and 9.3. Active fractions were pooled and re-focused. After the second fractionation, catalase activity increased to 1.52 x 10(-2) units/ml and was restricted to fractions ranging from pH 7.6 to 8.8. To this point a 121 fold purification was achieved. Native polyacrylamide gel electrophoresis analysis of active fractions revealed a band migrating between 272,000 and 132,000 daltons which showed catalase activity. Purification of C. albicans catalase will allow us to evaluate its potential role in protecting this opportunistic pathogen from products of the oxidative burst. Antibodies generated against the catalase provide means for the evaluation of neutralizing fungal defenses against products of the oxidative burst during phagocytosis.

Candida albicans↗
PubMed1991

Detection of catalase in rat heart mitochondria.

The presence of heme-containing catalase in rat heart mitochondria (20 +/- 5 units/mg) was demonstrated by biochemical and immunocytochemical analysis. Intact rat heart mitochondria efficiently consumed exogenously added H2O2. The rate of H2O2 consumption was not influenced by succinate, glutamate/malate, or N-ethylmaleimide but was significantly inhibited by cyanide. Hydrogen peroxide decomposition by mitochondria yielded molecular oxygen in a 2:1 stoichiometry, consistent with a catalytic mechanism. Mitochondrial fractionation studies and quantitative electron microscopic immunocytochemistry revealed that most catalase was matrix-associated. Electrophoretic analysis and Western blotting of the mitochondrial matrix fraction indicated the presence of a protein with similar electrophoretic mobility to bovine and rat liver catalase and immunoreactive to anti-catalase antibody. Myocardial tissue has a lower catalase-specific activity and a greater mitochondrial H2O2 production/g of tissue than most organs. Thus catalase, representing 0.025% of heart mitochondrial protein, is important for detoxifying mitochondrial derived H2O2 and represents a key antioxidant defense mechanism for myocardial tissue.

Animals↗
PubMed1992

Oxidation-reduction-sensitive binding of lung protein to rat catalase mRNA.

Air-breathing organisms experience an elevated concentration of oxygen mainly under two conditions. One occurs at birth when the O2 tension in the lung increases from approximately 25 torr present in utero to approximately 100 torr. The lungs, in particular, are also exposed to hyperoxia when oxygen is administered for therapeutic reasons. Under hyperoxic conditions, increased lung antioxidant enzyme activity is important for survival. The molecular basis for the increase in antioxidant enzyme gene expression under these circumstances is not well understood; in hyperoxia-exposed neonatal rats the elevation of lung catalase activity is not due to an increased rate of transcription but is associated with an increased concentration of catalase mRNA due to enhanced stability of the mRNA (Clerch, L.B., Iqbal, J., and Massaro, D. (1991) Am. J. Physiol. 260, L428-L433). We now show that neonatal rat lung protein forms specific complexes with catalase mRNA; this binding is redox-sensitive since when oxidizing agents are added binding is abolished but is restored by reducing agents. Our data also indicate lungs from hyperoxia-exposed rats have a larger proportion of catalase RNA-binding protein in oxidized form than lungs from air-breathing rats. This redox-sensitive binding of protein to catalase mRNA may be important in the control of catalase gene expression.

Aging↗
PubMedDate not supplied

[Dissociation of Penicillium vitale catalase under the effect of urea and acid pH].

Conditions are studied for Penicillium vitale catalase dissociation into subunits under the effect of urea (0.7-8.5 M) and acid pH (5.0-2.0). In 8.0 M urea (pH 5.0) a molecule of the P. vitale catalase dissociates with formation of the components, the sedimentation coefficient of which is 2.4+/-0.2S, the molecular weight is 153000+/-2800. Dissociation at pH 2.2 in 4.0 M urea results in formation of components with the sedimentation coefficient 2.2+/-0.3 S. The catalase molecule dissociation under the mentioned conditions is accompanied by a loss in the enzyme activity. The results obtained show that dissociation of the P. vitale catalase molecule requires more rigid conditions than dissociation of the animal catalase. At the same time the catalase after dissociation in 8.0-8.5 M urea loses its ability to reassociation with a decrease in the urea concentration up to 0.08 M.

Catalase↗
PubMed1991

Heat shock factor-independent heat control of transcription of the CTT1 gene encoding the cytosolic catalase T of Saccharomyces cerevisiae.

Transcription of the Saccharomyces cerevisiae CTT1 gene encoding the cytosolic catalase T has been previously shown to be derepressed by nutrient stress. To investigate whether expression of this gene is also affected by other types of stress, the influence of heat shock on CTT1 expression was studied. The results obtained show that expression of the gene is low at 23 degrees C and is induced rapidly at 37 degrees C. By deletion analysis, a promoter element necessary for high level induction by heat shock was located between base pairs -340 and -364 upstream of the translation start codon. This region was demonstrated to be sufficient for heat shock control by placing it upstream of a S. cerevisiae LEU2-lacZ fusion gene. Mutagenesis of the region showed that the response to heat shock is not mediated by a sequence similar to canonical heat shock elements, but by DNA elements also involved in nutrient control of transcription. Catalase T appears to have a function in protecting yeast cells against oxidative damage under stress conditions. Catalase T-containing strains are less sensitive to exposure to 50 degrees C ("lethal heat shock") than isogenic catalase T-deficient mutants, and catalase T-containing strains pretreated by incubation at 37 degrees C are less sensitive to H2O2 than pretreated catalase-deficient mutants.

Base Sequence↗
PubMed1988

Superoxide dismutase and catalase activities of cultured erythrocytes infected with Plasmodium falciparum.

It has already shown that catalase activity is significantly decreased in red cells of patients with P. falciparum. The mechanism suggested was by this enzyme inactivation through increased H2O2 generated during malarial infection. The present study was performed to verify this hypothesis. Catalase activities of red cells with high or low parasitemia in patients with P. falciparum were found to be lower than those of normal red cells. However, P. falciparum-infected red cells cultured for one week showed similar SOD and catalase levels to normal red cells. There was also no significant difference in the catalase levels between the parasitized and non-parasitized red cells. The difference in catalase activity of infected red cells before and after culture could be explained in terms of the activation of mononuclear cells and macrophages in vivo. During the sojourn of the parasitized red cells in close proximity to the macrophages of the spleen, they might trigger oxidative bursts resulting in increased H2O2. In order to protect themselves from oxidant damage, the catalase in the infected red cells could be inactivated by H2O2 resulting in the reduction of this enzyme.

Adult↗
PubMed1986

[The effect of catalase added to Löwenstein-Jensen medium on the rate of growth of M. tuberculosis].

In this study, the effect of catalase on the rate of growth Mycobacterium tuberculosis has been investigated. Thirty-five sputa were inoculated on the Löwenstein-Jensen medium and Löwenstein-Jensen medium modified by the addition of catalase 4 mcg/ml. Only four sputa were observed to have an early growth on the Löwenstein-Jensen medium with catalase five days than Löwenstein-Jensen medium. Of the 55 strains grown in the Löwenstein-Jensen medium the following results were obtained from the inoculations made in the Löwenstein-Jensen with catalase and Löwenstein-Jensen medium. At the end of a three week incubation in a medium with 5-10% CO2, a growth of 32 strains (58%) in the Löwenstein-Jensen medium with catalase and a growth of 21 strains (38%) in the Löwenstein-Jensen medium were observed Eleven strains (20%) were observed in the Löwenstein-Jensen medium with catalase and B strains (14%) in the Löwenstein-Jensen medium during the same time in normal atmosphere.

Catalase↗
PubMed1988

Morphological changes and catalase activity in the hearts of CD 1 mice following acute starvation or single doses of doxorubicin, epirubicin or mitoxantrone.

The cardiac morphology of CD 1 mice undergoing two different schedules of acute (5 day) starvation and that of animals treated with a single dose (15 mg/kg i.p.) of doxorubicin, epirubicin or mitoxantrone were studied by light microscopy. Determinations of heart catalase were also carried out. Mice subjected to moderate starvation had a mean weight reduction of 18.7% and did not show heart morphological damage. A slight increase (38%) of heart catalase specific activity occurred in these animals. In animals subjected to severe starvation the weight loss was 32.2%. In this case considerable heart damage, in the form of myofibrillar loss, and a striking increase of catalase (158.5%) were seen. In the drug groups comparable weight reductions (about 15%) occurred 5 days after the treatment. Moderate heart lesions, represented by myolysis and especially by myocytic microvacuolation, were observed and appeared to be of similar degree in the 3 drug groups. Catalase specific activity increased by 119.9% in the doxorubicin animals, by 73% in the epirubicin mice and by 30.3% in the mitoxantrone ones. Light microscopy made it possible to distinguish between cardiac alterations induced by starvation and those specifically induced by antiblastics. Catalase may be helpful to indicate the existence of heart damage but it does not correlate well with the severity of the lesions by antiblastics. An additional cause of heart catalase elevation might be the free radical generation induced by the anthracyclines but not by mitoxantrone.

Animals↗
PubMed1987

Effects of doxorubicin on mouse heart catalase.

The behaviour of heart and liver catalase was studied 4 days after the administration of different doxorubicin doses to CD 1 mice. The antiblastic increased the specific activity of the heart enzyme with a clear dose-response relationship (+27% after 5 mg/kg i.p.; +61% after 7 mg/kg; + 108% after 10 mg/kg; + 147% after 15 mg/kg). This did not occur in the liver where, on the contrary, a significant reduction of catalase (-31%) was noticed after the highest dose. Analyses by gel filtration excluded the possibility that doxorubicin induces major changes in the molecular properties of heart catalase. In vivo experiments with aminotriazole, which blocks catalase irreversibly, indicated that doxorubicin stimulates the synthesis of cardiac catalase. These findings are discussed with reference to the possible mechanisms of anthracycline cardiotoxicity. The catalase elevation could represent a reaction by the heart to free radicals generated by doxorubicin.

Amitrole↗
PubMed1978

Haemoprotein formation in yeast. III. The role of carbon catabolite repression in the regulation of catalase A and T formation.

Catalase A and T activities were investigated in two standard strains and three catalase regulatory cgr mutants of yeast in respiratory competent and incompetent states, which were under various degrees of glucose repression. The formation of catalase A was very sensitive to glucose repression and was characterized by a long delay in derepression. Deprivation of the energy source in respiratory incompetent cells prevented the derepression of catalase A. The lack of catalase A in respiratory imcompetent cells can be overcome by growing the cells in raffinose or by the prolongation of the fermentative phase of derepression. Catalase T is under control of different regulatory systems probably common with some other haemoproteins.

Catalase↗
PubMed1987

[Catalase activity of synovial fluid leukocytes in rheumatoid arthritis].

Catalase activity of rheumatoid synovial fluid measured by a gasometry was higher than that of osteoarthritic fluids, suggesting a possible origin of the catalase activity from synovial fluid leukocytes. Isoelectric focusing polyacrylamide gel electrophoresis of the extract from polymorphonuclear leukocytes (PMN) of rheumatoid synovial fluid exhibited two to four achromatic bands and one dark band of catalase activity. Catalase staining of synovial fluid cells with diaminobenzidine revealed a marked activity in PMN, no or weak activity in monocytes and negative activity in lymphocytes. Catalase scores of the PMN in rheumatoid synovial fluid were lower than those of osteoarthritic fluid and of normal peripheral blood PMN. Ultrastructural localization of catalase activity in leukocytes of rheumatoid synovial fluid was examined by diaminobenzidine staining. Electron dense deposits were observed in granules, probably peroxisomes and in cytoplasm of the PMN and also in microperoxisomes of the monocyte.

Adult↗
PubMed1986

[Kinetic properties of catalase and its conjugates with strophanthin K in ethanol oxidation by cumyl hydroperoxide].

The gluconic fragment of strophantin K oxidation by sodium metaperiodate yields a dialdehyde derivate conjugated with catalase. The conjugate obtained contains 11 molecules of cardiac glucoside. Adsorption and circular dichroism spectra of the native enzyme and its conjugate were compared and structural differences between both samples were revealed. The kinetics of ethanol oxidation into acetaldehyde by cumene hydroperoxide was studied at 30 degrees C in the phosphate buffer pH 6.6; this reaction was shown to proceed with the participation of catalase and its cat-str conjugate. The catalytic constants for catalase are 1.2-1.5 times as high as those for cat-str, whereas the Km values for both substrates for the conjugate as 1.5-2 times as high as those for catalase. Catalase modification by strophantin K increases the enzyme thermostability up to the isokinetic point of 40 degrees C; above this threshold the cat-str thermostability decreases as compared with the native enzyme. The thermodynamical activation parameters for catalase and cat-str inactivation were determined.

Animals↗
PubMed1977

L-Dopa peroxidase activity of human erythrocyte catalase.

The human red cell hemolysate was found to have 3-(3',4'-dihydroxphenyl)-L-alanine (L-dopa) peroxidase activity. During the purification of glutathione peroxidase and catalase by ammonium sulfate precipitation, ion exchange chromatography. Sephadex gel filtration, and preparative polyacrylamide disc electrophoresis, the L-dopa peroxidase activity was found to be associated with catalase. Both sodium azide, 8 mM, and 3-amino-1,2,4-triazole, 50 mM, besides inhibiting catalase, inhibited the L-dopa peroxidase activity in each fraction. Ethylenediamine tetraacetic acid (EDTA), 4 mM, had no effect on catalase or L-dopa peroxidase activity, indicating that the oxidation of L-dopa is not a nonenzymatic process mediated by metal ions. Although the electrophoretic mobility of catalase, L-dopa peroxidase, and glutathione peroxidase are similar, a homogeneous preparation of glutathione peroxidase was free of L-dopa peroxidase activity. L-Dopa peroxidase in human red cells was co-purified with catalase.

Azides↗
PubMed1979

[Quantitative indices of the activity and the electrophoretic characteristics of staphylococcal catalase].

The average levels of activity of intracellular and extracellular catalase were determined. The activity of intracellular catalase was shown to be significantly higher than that of extracellular catalase, the average level of activity of extracellular catalase being higher in S. aureus than in S. epidermidis. In most of the strains one zone of extracellular catalase and two molecular forms of intracellular catalase were revealed by means of polyacrylamide gel electrophoresis.

Catalase↗
PubMed1978

An analysis on the specificity of the histochemical techniques already proposed to detect catalases and peroxidases.

The spot test carried on filter paper strips appears as a very suitable technique to investigate the reactivity of catalases, peroxidases, porphyrins (bilirubin and protoporphyrin), metalloporphyrins (haemoglobin, haemin, haematin, chlorophyll and cyanocobalamin), ferric and ferrous salts. By using this technique the specificity of the already proposed techniques admitted as appropriate to detect histochemically peroxidases and catalases was investigated. The results shown from the already proposed techniques to detect peroxidases only the alpha-naphthol reaction is somewhat specific for this enzyme, if the results were taken immediately. However, if the results were taken after 24 h, the reaction loose all specificity. The other techniques proposed to detect peroxidase are not specific, either concerning the discrimination between catalases and peroxidases activity or regarding the possibility to differenciate an enzymic from a catalytic activity provided by haemic iron containing compounds and sometimes by iron salts. Our histochemical technique already proposed as suitable to detect catalases seams to be specific, since peroxidases do not react positively. By replacing benzidine for some others hydrogen donors the peroxidases histochemical techniques remain not specific and are unable to discriminate this enzyme from catalases. Porphyrins (protoporphyrin and bilirubin), magnesium and cobalt containing metalloporhyrins (chlorophyll and cyanocobalamin) do not produce oxidation of any hydrogen donors used. Iron salts are also able to give positive results with some techniques already proposed as suitable for peroxidases and catalases detection.

Animals↗