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1.
L Góth 《Enzyme》1989,41(4):191-199
Catalase enzyme was purified from human erythrocytes. The modified procedure of M?rikofer-Zwez et. al. [Eur. J. Biochem. 11: 49-57, 1969] yielded erythrocyte catalase with high specific activity and with one band on SDS polyacrylamide gel. Its other characteristics (isoelectric point; E405/280, E1%1cm at 280 nm and 405 nm) were in agreement with previously described findings. The results obtained for molecular mass, electrophoretic mobility, chromatographic behaviour on CM-Sepadex gel, addition test, and change of electrophoretic mobility in human serum showed differences between human erythrocyte catalase and bovine liver catalase. These results suggest that human erythrocyte catalase and bovine liver catalase are two distinct catalase forms.  相似文献   

2.
Summary In Japanese-type acatalasemia erythrocytes, the presence and properties of residual catalase were determined and compared with those of normal erythrocyte catalase. Residual catalase activity was proved by titration, active staining after polyacrylamide gel electrophoresis, and measurement of oxygen evolution. Residual catalase protein, demonstrated by double immunodiffusion, was similar to that of normal catalase. The properties of residual catalase activity were identical with those of normal catalase activity. It occurred as three fractions of equal specific activity by DEAE column chromatography. These observations suggest that Japanese-type acatalasemia contains residual catalase with properties similar to those of normal catalase.  相似文献   

3.
Human granulocyte catalase (hydrogen peroxide:hydrogen peroxide oxidoreductase, EC 1.11.1.6) was purified from chronic myeloid leukemia cells. The purification procedure included heat precipitation, ammonium sulphate fractionation, DEAE-Sephadex chromatography, gel chromatography on Sephadex G-200 and isoelectric focusing with an approximate yield of 30% and a 1000-fold purification. The molecular weight of the subunit obtained by sodium dodecyl sulphate electrophoresis was 65 800. So20,w was 11.6 +/- 0.24. The pH-optimum was 6.6-6.7 and the spectrum showed a major peak at 405 nm and shoulders at 500, 540 and 625 nm typical for catalase. The electrophoretic mobility was towards the anode at pH 8.6 and identical to normal granulocyte and erythrocyte catalase. These three species of catalase gave the reaction of identity on immunodiffusion and crossed immunoelectrophoresis. The content of catalase and its activity of isolated granulocytes were approximately identical in normal and chronic myeloid leukemia granulocytes while the specific activity of leukemic catalase was higher than normal. No difference in catalase content was found between mature and immature leukemic granulocytes.  相似文献   

4.
Levels of human erythrocyte catalase activity were determined in 38 patients with thyroidal dysfunction. In patients with hyperthyroidism, erythrocyte catalase activities were found to be higher than the levels of normal subjects (P less than 0.001). In hypothyroidism, erythrocyte catalase activities were of the same order as those of normal subjects. Significantly high positive correlation was found between erythrocytes catalase activity and the levels of thyroxine (r = 0.5794, n = 36, P less than 0.001), and slight positive correlation was detected between catalase activity and the levels of triiodothyronine (r = 0.3978, n = 33, P less than 0.05). A decreased erythrocyte catalase activity was observed when erythrocytes lysate was incubated with thyroid hormones. It was suggested that erythrocyte catalase activity had close relationship with thyroid state, however, direct effect of thyroid hormones were not observed on erythrocyte catalase assay system in vitro.  相似文献   

5.
Summary Specific antisera were produced against chicken reticulocyte dehistonized chromatin. The antisera reacts strongly with chicken reticulocyte chromatin, but only marginally with chicken erythrocyte chromatin. There is no reticulocyte antigen detected in chicken liver. Reticulocyte maturation is accompanied by a gradual decrease in the chromatin immunological activity and template capacity. The reduction of immunological activity is due to the change of chromatin conformation during erythrocyte maturation. Dehistonization and sonication of erythrocyte chromatin raises the erythrocyte chromatin immunological activity to levels similar to those of reticulocyte chromatin. The erythrocyte nuclear antigens are class specific, not being found in frog erythroid cell or murine Friend leukemia cell chromatins.  相似文献   

6.
Plasmodium berghei, a murine malaria, lacks endogenous superoxide dismutase (SOD). Instead it appears to take up and concentrate SOD from its host cell, the erythrocyte. We now demonstrate that the adopted host enzyme is localized in granules which are probably lysosomes. In addition, isolated P. berghei parasites contain only low levels of catalase, probably as a result of contamination of the preparation with host cell material. Thus, the cytosol of this organism appears to be deficient in enzymes which protect against damage by activated oxygen.  相似文献   

7.
A method for isolation and purification of catalases from the culture of Micrococcus sp. n. grown under aeration conditions is described. Heme-containing catalase (I) and the protein possessing a catalase activity (II) were separated by fractionation with ammonium sulfate. The specific activity of the highly purified protein causing degradation of H2O2 is 200 times less than that of the heme-containing enzyme. The molecular weights of catalases I and II as determined by electrophoresis in polyacrylamide gel gradient 4/30% are 240000 and 130000, respectively. The method described is designed at rapid isolation of preparative amounts of catalases from Micrococcus sp. n.  相似文献   

8.
9.
Human and murine catalases can be separated electrophoretically as single bands of different mobility. In man-mouse somatic cell hybrids, however, detection of human catalase is precluded by the complexity of banding patterns resulting from interference of a catalase-modifying enzyme activity. We have identified human catalase in hybrid clones by Laurel electrophoresis employing a specific anti-human catalase antibody, and by exploiting heat stability differences. Catalase co-segregates with LDH A and is probably located on the short arm of chromosome 11.  相似文献   

10.
A rat liver protein with both phosphoenolpyruvate carboxykinase ferroactivator activity and catalase activity has been purified to near-homogeneity. The protein has a native molecular weight of 240,000 and is composed of four identical subunits containing ferriprotoporphyrin IX prosthetic groups. The visible spectrum has absorbance maxima at 403, 500, 530, and 620 nm; it is not reduced by dithionite. The spectrum, physical properties, and specific activity are almost identical with those of catalases from other sources, and the protein has been tentatively identified as rat liver catalase. The protein exhibited partial reactivity in double immunodiffusion plates to antiserum prepared against rat liver ferroactivator isolated by a previous method (Bentle, L. A., and Lardy, H. A. (1977) J. Biol. Chem. 252, 1431-1440) raising the possibility that the original ferroactivator and rat liver catalase are structurally related. Inactivation of catalase by 3-amino-1,2,4-triazole was accompanied by loss of ferroactivator activity as well. The apparent specific activity of ferroactivator, as well. The apparent specific activity of ferroactivator, whether heme-containing or not, can be increased between 2- and 100-fold by the inclusion of bovine serum albumin, HCO3-, or a combination of the two in the incubation.  相似文献   

11.
A specific interaction of human erythrocyte catalase with the inner surface of the red cell membrane was demonstrated. The dependency of catalase affinity on pH and ionic strength implies that the interaction is dominated by electrostatic forces. Scatchard analysis of the binding at pH 6.0 and 5 mm Mes buffer reveals a single class of approximately 106 binding sites/ghost with an association constant of 2.5 × 107m?1. The membrane-bound catalase retains its enzymatic activity. Competition binding studies of catalase and other proteins known to associate with the membrane inner surface were carried out. It was found that the binding of catalase is inhibited by aldolase, glyceraldehyde-3-phosphate dehydrogenase as well as by hemoglobin. The advantage of membrane-bound catalase in protection of the cell membrane against peroxidative damages is discussed.  相似文献   

12.
The catalase level of Bacteroides distasonis (ATCC 8503, type strain) varied with the amount of hemin supplied to the medium when the cells were grown in either a prereduced medium containing 0.5% peptone, 0.5% yeast extract, and 1% glucose or in a prereduced, defined heme-deficient medium. The effect of hemin on catalase production could not be duplicated by ferrous sulfate or ferrous ammonium citrate. Catalase activity reached peak values in late log phase, whereas superoxide dismutase specific activity remained constant throughout the culture growth cycle. The catalase was a nondialyzable, cyanide and azide-sensitive, heat-labile protein that coeluted with bovine erythrocyte catalase from Sepharose 6 B. Analysis of polyacrylamide gels stained for catalase activity and for heme showed a correspondence between the single catalytic activity band and one of three heme-protein bands. These data suggest a heme-protein of approximately 250,000 molecular weight. The superoxide dismutase was a cyanide-insensitive protein of approximately 40,000 molecular weight that migrated electrophoretically on acrylamide gels as a single band of activity.  相似文献   

13.
C Wata?a  M Bryszewska  B Stefaniak  S Nowak 《Cytobios》1986,47(189):101-105
Enzyme activities of erythrocyte superoxide dismutase (SOD), peroxidase and catalase in groups of diabetic children, the duration of the disease and control qualities were compared with respective values obtained for healthy children. Generally the disease duration was clearly found to affect SOD activity, and catalase activity only a little. No similar influence of either diabetes duration or control was noticed in the case of peroxidase. SOD activity was diminished in diabetics when compared with control subjects, and in turn peroxidase and catalase activities were generally elevated. The diminution in SOD activity may constitute a reason for enhanced pancreatic cells susceptibility to deterioration, followed by the augmentation of peroxidase activity with an 'elaborated' mechanism compensating for the loss of erythrocyte SOD activity.  相似文献   

14.
Glutathione peroxidase (GSH-Px; glutathione: hydrogen peroxide oxidoreductase; EC 1.11.1.9), catalase (H2O2: H2O2 oxidoreductase; EC 1.11.1.6) and superoxide dismutase (superoxide: superoxide oxidoreductase; EC 1.15.1.1) were coisolated from human erythrocyte lysate by chromatography on DEAE-cellulose. Glutathione peroxidase was separated from superoxide dismutase and catalase by thiol-disulfide exchange chromatography and then purified to approximately 90% homogeneity by gel permeation chromatography and dye-ligand affinity chromatography. Catalase and superoxide dismutase were separated from each other and purified further by gel permeation chromatography. Catalase was then purified to approximately 90% homogeneity by ammonium sulfate precipitation and superoxide dismutase was purified to apparent homogeneity by hydrophobic interaction chromatography. The results for glutathione peroxidase represent an improvement of approximately 10-fold in yield and 3-fold in specific activity compared with the established method for the purification of this enzyme. The yields for superoxide dismutase and catalase were high (45 mg and 232 mg, respectively, from 820 ml of washed packed cells), and the specific activities of both enzymes were comparable to values found in the literature.  相似文献   

15.
The (Ca2+ + Mg2+)-dependent ATPase of human erythrocyte membranes was solubilized with deoxycholate and purified by calmodulin affinity chromatography to yield a functional enzyme. The method gave an enzyme purified 207-fold as compared with that of the erythrocyte membranes. The molecular weight of the ATPase was in the range 135 000-150 000, as revealed by a single major band after electrophoresis on dodecyl sulphate/polyacrylamide gels. The isolated enzyme was highly sensitive to calmodulin, since the activity was increased about 9-fold. At 37 degrees C and in the presence of calmodulin the purified ATPase had a specific activity of 10.1 mumol/min per mg of protein. Triton X-100 or deoxycholate stimulated the calmodulin-deficient enzyme in a concentration-dependent fashion whereby the calmodulin-sensitivity was lost. The purification method is suitable for studying the lipid-sensitivity of the ATPase, since the lipids can easily be exchanged without a significant loss of activity. A purification procedure described by Niggli, Penniston & Carafoli [(1979) J. Biol. Chem. 254, 9955-9958] resulted in an enzyme that indeed was pure but was lacking a predominant feature, namely the modulation by calmodulin.  相似文献   

16.
The assembly and the use of a simple airtight pressurized reaction vessel are described for the measurement of catalase activity with a micro oxygen electrode in an optically heterogenous medium. The oxygen concentration is expressed as the ratio of observed current to the current in an air-saturated solution. Thus, an individual standard can be obtained for each measurement and the calibration is less affected by changes in the amplification factor. Different procedures for calibration of the oxygen electrode were compared. Specific activities of crystalline catalase, of red blood cells from humans and from normal or acatalasemic mice, and of liver homogenates from normal or amino-triazole-pretreated rats were determined. The specific catalase activity of human erythrocytes, as found by this method, agrees with that obtained photometrically.  相似文献   

17.
Exposure to a sublethal dose of endotoxin offers protection against subsequent oxidative stresses. The cellular mechanisms involved in generating this effect are not well understood. We evaluated the effect of endotoxin on antioxidant enzymes in liver peroxisomes. Peroxisomes have recently been shown to contain superoxide dismutase (SOD) and glutathione peroxidase (GPX) in addition to catalase. Peroxisomes were isolated from liver homogenates by differential and density gradient centrifugations. Endotoxin treatment increased the specific activity of SOD and GPX in peroxisomes to 208% and 175% of control activity, respectively. These findings correlated with increases in peroxisomal SOD and GPX proteins observed by immunoblot. Although the quantity of catalase protein was increased when assessed by immunoblot analysis, the specific activity of catalase was decreased to 68% of control activity. Activation of catalase with ethanol only restored catalase activity to control levels suggesting that catalase had undergone irreversible inactivation. The observed increase in GPX activity may represent a compensatory mechanism triggered by accumulating H2O2. The data presented here suggest for the first time that mammalian peroxisomal antioxidant enzymes are altered during the oxidative injury of endotoxin treatment.  相似文献   

18.
This investigation was focussed on the gravity of tissue injury caused by complete ischemia (for five min) and hypoxia (for three weeks) in the cerebral cortex (homogenate) and the erythrocyte lysate or the erythrocyte membrane of the rat in order to investigate if the changes that occur in brain tissue are reflected in the erythrocyte. To this end, glutathione (GSH), superoxide dismutase (SOD) and catalase were measured, also alterations in beta-adrenoceptor density under these two conditions were examined. It was found that in ischemia partial parallelism in changes that occur in the central nervous system (cerebral cortex) and the erythrocyte exists. The SOD activity became higher and the beta-adrenoceptor density (measured as specific (-)-[125I] iodocyanopindolol binding) was decreased in both tissues. However after the hypoxic condition we established a decrease in the number of beta-adrenoceptors in the cerebral cortex but an increase in beta-adrenoceptor density in the erythrocyte.  相似文献   

19.
A method for the isolation of catalase T deficient mutants of Saccharomyces cerevisiae is described. Ten mutants lacking catalase T and belonging to 5 complementation groups were isolated. CTT1 locus was identified as the structural gene for catalase T. It is under the control of CTT2, CTT3 and CTT4 loci.  相似文献   

20.
The dynamics of the level of catalase and superoxidedismutase (SOD) expression by S. aureus isolated in persistent experimental kidney infection is described. A rise in the activity of the staphylococci under study during transition of the infectious process from the alteration to persistence stage. Changes in the expression of SOD and catalase were observed simultaneously with a decrease in hemolytic, fibrinolytic and protease activity, as well as in the presence of more pronounced clumping and an increase in the production of protein A, the antilysozyme and anticomplement activity of staphylococcal clones obtained from kidney tissue. The significance of all above-mentioned phenomena in the persistence of microorganisms is discussed.  相似文献   

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