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Coisolation of glutathione peroxidase, catalase and superoxide dismutase from human erythrocytes.

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.

Catalase↗

Isolation of cDNA clones coding for peroxisomal proteins of Candida tropicalis: identification and sequence of a clone for catalase.

A cDNA library, complementary to mRNAs of alkane-grown Candida tropicalis, was screened by differential DNA dot-blot hybridization with [32P]cDNA reverse-transcribed from mRNA of alkane-grown cells or from cells in which peroxisome formation was repressed by growth on glucose. 9% of the library encodes alkane-induced sequences. The cell-free translation products of eight hybrid-selected mRNAs were characterized by SDS-polyacrylamide gel electrophoresis and fluorography: most of them are probably peroxisomal proteins. Among these, a catalase clone was identified by immunoprecipitation of the translation product with anti-catalase. The clone was sequenced: the inferred amino acid sequence is homologous to the carboxytermini of mammalian and Saccharomyces cerevisiae catalases. C. tropicalis catalase mRNA is 1.7-1.8 kb long by Northern analysis, of which 1.5-1.6 kb is required to code for the 57 kDa polypeptide. Catalase mRNA (assayed by dot-blot hybridization) is strikingly induced in C. tropicalis by growth on alkanes, suggesting that peroxisome induction is transcriptionally regulated. This sublibrary of alkane-induced, mostly peroxisomal clones, together with a recently developed cell-free peroxisome protein import assay, will permit investigation of the targeting of proteins to peroxisomes.

Amino Acid Sequence↗

Reversible inhibition and irreversible inactivation of catalase in presence of hydrogen peroxide.

Spectroscopic and kinetic investigations have been carried out on catalase from bovine liver and from Aspergillus niger to address the mechanism of activity loss at high hydrogen peroxide concentrations (0.01 to 2 M). The mammalian enzyme was both reversibly inhibited and irreversibly inactivated in the presence of hydrogen peroxide, whereas the fungal enzyme did not show any reversible inhibition. A comparison of reaction rates with catalase preparations containing different proportions of Compound III indicated that the formation of Compound III is responsible for the reversible inhibition of bovine liver catalase at high H2O2 concentrations. Superoxide radical did not appear to be the inactivating species in this mechanism. Kinetic modelling emphasises the role of Compound III in both types of activity loss. It shows that the higher activity of A. niger catalase at high substrate concentration, compared to bovine liver catalase, the lack of reversible inhibition of the former and its lower rate of irreversible inactivation may be attributed both to a high rate of conversion of Compound III into native form and to a low rate of conversion of Compound I to Compound II.

Animals↗

Studies on catalase compartmentation in digitonin-treated rat hepatocytes.

The cellular compartmentation of catalase was studied in digitonin-permeabilized rat hepatocytes. A biphasic dose-response curve was observed for the unmasking of catalase activity by digitonin in latency studies. About 40-60% of the total catalase activity was seen in the range of 5-200 microM digitonin compared to 13% free activity in control preparations without digitonin. The free catalase activity began to increase again above 300 micron digitonin, and all latency was lost around 500 microM and above. These results indicate that there exists in rat hepatocytes catalase with two levels of crypticity to digitonin, only one of which was seen in a mixed organelle preparation containing peroxisomes.

Animals↗

Protection of cultured endothelial cells from hydrogen peroxide-induced injury by antibody-conjugated catalase.

The cytoprotective features of catalase-antibody conjugate prepared by covalent conjugation of catalase to rabbit antibody against mouse IgG is described. The bifunctional cross-linking agent m-maleimidobenzoic acid N-hydroxysuccinimide ester (MBS) was used for conjugation. Functionally active conjugate binds specifically to the plastic-adsorbed mouse IgG and to the surface of live human endothelial cells treated with mouse antiserum against human endothelial cells. Up to 4 units of catalase activity can bind to 1 cm2 of the endothelial monolayer. The targeted catalase protects endothelial cells from cytotoxic action of hydrogen peroxide: the minimal cytotoxic concentration of H2O2 for protected cells is 80-times higher than for intact cells. This effect is attributed partly to local reduction of H2O2 concentration in the cell microenvironment. Targeted catalase was estimated to reduce H2O2 concentration 8-fold near the cell surface with respect to average total concentration.

Antibodies↗

Changes in catalase activity and concentration during ovarian development and differentiation.

The ovaries of immature rats were used to prepare a peroxisome-enriched fraction by differential centrifugation. Following gonadotropin stimulation, which caused large numbers of follicles to develop into corpora lutea, the specific activity of catalase in the peroxisome-enriched fraction increased 5-fold, while catalase recovered in the post-30,000 x g supernatant did not increase in activity. The increase in catalase specific activity in the peroxisome enriched fraction was shown to be due to an increased concentration of the enzyme as determined by Western blotting. Catalase in pig granulosa cells also increased in specific activity as the follicles aged and luteinized. This increase appeared to parallel increases in the concentration of cytochrome P-450scc. We conclude there is a differential regulation of the peroxisomal and cytosolic pools of rat ovarian catalase.

Animals↗

Adaptation to hyperoxia in the neonatal rat: kinetic parameters of the oxygen-mediated induction of lung superoxide dismutases, catalase and glutathione peroxidase.

The activities of the enzymes superoxide dismutase, catalase and glutathione peroxidase increase in the lungs of neonatal rats exposed to normobaric hyperoxia. The oxygen-mediated increase in activity of these enzymes, known from previous studies to be an inductive response, was studied in 10- and 25-day-old rats as a function of both oxygen concentration and length of time of exposure to greater than 95% oxygen. In the lungs of 10-day-old rats the increase in superoxide dismutase, catalase, and glutathione peroxidase occurs only at 80% ambient oxygen or greater. In 25-day-old rats a similar pattern of response occurs with pulmonary catalase and glutathione peroxidase. However, unlike the response in 10-day-old rats, pulmonary superoxide dismutase does not increase in oxygen-exposed 25-day-old rats. The time course of enzyme induction was different for 10-day-old rats compared with 25-day-old rats. Exposure of 10-day-old rats to 95+% oxygen resulted in a significant increase in activity of superoxide dismutase after only 4 h when compared with air-exposed control animals. Catalasee and glutathione peroxidase in the same age group increased significantly after 6 h and 12 h of exposure to oxygen, respectively. Maximal levels of superoxide dismutase, catalase and glutathione peroxidase were reached after 6, 12 and 24 h of exposure to hyperoxia, respectively. This level of activity was then maintained throughout the subsequent exposure time up to 96 h. The activity of pulmonary catalase and glutathione peroxidase in 25-day-old rats did not increase significantly after 6 h of exposure to hyperoxia. An apparent plateau of increased activity was reached after 24 h of exposure. As observed with the 3 enzymes in 10-day-old rats, maximal enzyme activities were maintained throughout the subsequent period of oxygen exposure up to 96 h.

Adaptation, Physiological↗

Regulation of hydrogen peroxide in eye humors. Effect of 3-amino-1H-1,2,4-triazole on catalase and glutathione peroxidase of rabbit eye.

Activities of catalase (H2O2: H2O2 oxidoreductase, EC 1.11.1.6) and GSH peroxidase (GSH: H202 oxidoreductase, EC 1.11.1.9) have been measured in iris, ciliary body, retina, corneal epithelium, corneal endothelium, lens capsule-epithelium and decapsulated lens. 3-Amino-1H-1,2,4-triazole is a specific inhibitor of catalase and a potent cataractogenic agent. We observed marked inhibition of catalase activity in these tissues 1--6 h after the administration of a single intravenous dose of 1 g 3-aminotriazole per kg body weight in rabbit. This was associated with a 2--3-fold increase in the H2O2 concentrations of aqueous humor and vitreous humor. The increased peroxide concentrations were restored to the physiological levels as the catalase activity of eye tissues gradually returned to normal with time after injection. Under the conditions, GSH peroxidase activity of the afore-mentioned eye tissues was unaltered, GSH and protein sulfhydryl of lens were not changed, and ascorbic acid of aqueous humor and vitreous humor was not significantly altered. Based on these findings our conclusion is that catalase of eye tissues regulates the endogenous H2O2 in eye humors to the physiological level. We speculate that H2O2 may be the triggering factor in cataract induced by 3-aminotriazole.

Amitrole↗

The peroxidatic and catalatic activity of catalase in normal and acatalasemic mouse liver.

Monomeric, dimeric and tetrameric forms of mouse liver catalase have been shown to express peroxidatic activity while the tetrameric form expresses the catalatic activity. Autosomally inherited acatalasemia, produced by X-ray irradiation of mice results in almost complete loss of catalatic activity of catalase but has o effect on the peroxidatic activity. Liver catalase from normal and acatalasemic mice was purified by following the catalatic and peroxidatic activity, respectively. Antiserum produced in rabbit against catalase from normal mouse completely precipitated the catalatic and peroxidatic activity from normal liver, and peroxidatic activity from the acatalasemic liver homogenate. Similar results were obtained when antiserum against peroxidase from acatalasemic mice was used. These studies indicate that acatalasemia in mice is due to a structural gene mutation which leads to synthesis of structurally altered catalase subunits. The altered subunits express peroxidatic activity but do not combine to form a tetramer which expresses catalatic activity.

Animals↗

Catalase in cultured skin fibroblasts from patients with the cerebro-hepato-renal (Zellweger) syndrome: normal maturation in peroxisome-deficient cells.

We have compared the properties of catalase in cultured skin fibroblasts from patients with the cerebro-hepato-renal (Zellweger) syndrome, in which peroxisomes are deficient, with those of catalase in fibroblasts from control subjects. The enzymes from the two types of fibroblasts are indistinguishable with respect to kinetic properties, subunit size and molecular mass of the native enzyme. The turnover of the enzyme, measured by following the rate of reappearance of catalase activity in fibroblasts after irreversible inactivation of existing molecules by 3-aminotriazole treatment of the cells, was the same in Zellweger fibroblasts as in control cells. These findings indicate that normal maturation of catalase can occur in the soluble cytoplasm and provide an explanation for the occurrence of extra-peroxisomal catalase in tissues and cells.

Brain Diseases↗

Catalase, superoxide dismutase and glutathione peroxidase activities of lung and liver during human development.

The developmental expression of catalase, superoxide dismutase (both Mn-SOD and Cu/Zn-SOD) and glutathione peroxide activities were determined in human lung and liver from 10 wk gestation to 3 months following birth. Pulmonary superoxide dismutase and glutathione peroxidase activities did not change appreciably over this period. Catalase activity however, increased from 20.9 +/- 7.8 U/mg protein (n = 29) at 11-20 wk gestation to 73 +/- 27.5 U/mg protein (n = 30; P less than 0.001) following normal delivery (41-60 wk post-conceptual age). Lung catalase activity was temporally associated with the late gestational increase in the fractional content of lung DPPC (r = 0.79, P less than 0.01). In contrast with the lung, liver total superoxide dismutase activity increased from 2.5 +/- 0.6 U/mg protein (n = 27) between 11 and 20 wk gestation to 9.4 +/- 4.4 U/mg protein after term (n = 22; P less than 0.001). Since hepatic Mn-superoxide dismutase activity did not change over this period, the increase was attributed to elevated expression of Cu/Zn-superoxide dismutase. Liver glutathione peroxidase activities remained relatively constant during the same period, while hepatic catalase activity, although constant during gestation (60 +/- 15.6 microU/mg protein), increased significantly following birth (99.7 +/- 33.0 microU/mg protein; P less than 0.001). These results demonstrate that the developmental expression of antioxidant enzymes differs between tissues and that, unlike many commonly used laboratory species, only increased expression of catalase activity is associated with human lung development.

Aging↗

Catalase enzymatic activity and electrophoretic patterns in adult amphibians--a comparative study.

Catalase electrophoretic patterns and enzymatic activities were measured in four organs of two anuran species, Rana ridibunda perezii and Discoglossus pictus. The D. pictus enzyme appeared as two distinguishable bands, whereas R. ridibunda catalase was monomorphic. Electrophoretic mobility of the major D. pictus catalase band was greater than that of R. ridibunda. Enzymes from both species showed slower mobility than that from bovine liver. Catalase activities did not show significant differences according to sex in any of the organs tested in R. ridibunda. Enzyme activities were similar in liver, kidney and brain when both species were compared. Only the heart showed much higher activity in D. pictus than in R. ridibunda. The catalase activity levels followed the order: liver greater than kidney greater than heart in both species. The heart showed higher activity than the brain in D. pictus but not in R. ridibunda.

Animals↗

Catalase activity during the development of the parasitic nematode, Ascaris suum.

1. Catalase activity was partially purified from body wall muscle of the parasitic nematode, Ascaris suum, and was similar to catalases isolated from mammalian tissues. It exhibited a broad pH optimum and was unaffected by 2 mM ethylenediaminetetra-acetate. In contrast, it was inhibited reversibly by 1 mM cyanide and irreversibly by prior incubation in 40 mM 3-amino-1:2:4-triazole for 1 hr or heating at 80 degrees C for 15 min. 2. Catalase activity was highest in the unembryonated "egg" and decreased dramatically as development proceeded. 3. Catalase activity in adult body wall muscle was similar to that in rat skeletal muscle, but dramatically lower than that in rat liver. Catalase activity was barely detectable in A. suum testis. 4. Cytochrome-c peroxidase activity did not appear to be present in adult A. suum muscle mitochondria.

Animals↗

Inhibition of the peroxidatic activity of catalase towards alcohols by the aldehyde dehydrogenase inhibitor cyanamide.

Recent results have suggested that catalase is responsible for activating cyanamide to a metabolite which is a potent inhibitor of aldehyde dehydrogenase. In the present report, cyanamide was shown to inhibit the peroxidatic activity of catalase with alcohols such as ethanol or methanol. Inhibition by cyanamide required a brief incubation period with catalase. Ethanol prevented this inhibition of catalase if added before or at the same time as cyanamide, suggesting that ethanol may protect against the activation of cyanamide by catalase.

Alcohols↗

Age-related changes in catalase and peroxidase activities in the excised leaves of Eleusine coracana Gaertin. cv PR 202 during senescence.

Changes in the activities of the enzymes catalase and peroxidase were studied in the excised leaves of ragi (Eleusine coracana Gaertn. cv PR 202) plants belonging to different ages. Catalase exhibited a positive and peroxidase a negative correlation with the changes in chlorophyll. Catalase and peroxidase were negatively correlated with each other. Peroxidase exhibited an age-related drift in its activity. Kinetin could maintain the levels of chlorophyll and catalase, and also caused an increase in peroxidase activity. Both indoleacetic acid and gibberellic acid had no effect on the changes of chlorophyll but increased peroxidase activity. Catalase levels were maintained by indoleacetic acid but gibberellic acid had no effect on this enzyme.

Catalase↗

Effect of a spinal cord photolesion injury on catalase.

Ischemic injury to the spinal cord results in cell and tissue damage. Oxygen free radicals have been implicated in post-ischemic cell injury and death while free radical scavengers like superoxide dismutase and catalase are associated with an amelioration of ischemic injury. Measurement of catalase enzyme activity or protein in ischemic tissue presents mechanical problems due to extensive tissue destruction. Therefore, we looked at the effects of a photochemical lesion (which reproduces ischemic injury) on the levels of catalase mRNA in the spinal cord tissues of rodents under various experimental conditions. A significant depletion in the levels of catalase mRNA was observed in the spinal cord tissues of rats that received a severe lesion and were sacrificed 6 days post-lesion, while levels of catalase mRNA in the spinal cord tissues of similarly lesioned rats sacrificed 14 days post-lesion showed a return to control values.

Animals↗

The regulation of alcohol consumption in rats: the role of alcohol-metabolizing enzymes-catalase and aldehyde dehydrogenase.

Aldehyde dehydrogenase (ALDH) and catalase enzymatic activities in brain were assayed and compared to measures of alcohol consumption in two groups of animals screened and maintained on free-choice alcohol access under different conditions. In the first group of Long-Evans rats screened and maintained in home cages, mean alcohol intake was 3.49 g/kg/day with a range of 1.69-5.33 g/kg/day. When alcohol intake (g/kg), total ALDH, low K(m) ALDH, and catalase activities were entered in a multiple regression, a significant correlation of r = 0.51 (p < 0.05) was obtained. In the second group of rats consisting of Long-Evans, P, and NP rats screened using a drinkometer procedure, a multiple correlation between ALDH and catalase enzyme activities and alcohol intake of r = 0.42 (p < 0.05) was obtained. There was a strong relationship between the frequency of alcohol drinking bouts and the activities of catalase and ALDH (r = 0.68, p < 0.0001). The P rats had significantly higher catalase activities than either the NP or Long-Evans rats. The results of the present study confirmed earlier reports on the role of alcohol-metabolizing enzymes in the regulation of alcohol intake. The results also highlighted the fact that the activity of these alcohol-metabolizing enzymes may play a mediating role in patterns of alcohol intake displayed by animals selected for high and low alcohol drinking and also unselected animals.

Alcohol Drinking↗

Role of oxyradicals in the inactivation of catalase by ozone.

The antioxidant enzymes, catalase and superoxide dismutase, are inactivated upon exposure to ozone. In this study, the mechanism of this inactivation was examined using catalase as a model system. The data show that the inactivation of catalase is dependent on ozone concentration, time of exposure, and pH. Loss of catalase activity is accompanied with loss of the heme spectra. Tiron, desferal-Mn, trolox-c, and pyruvate protect the enzyme against ozone inactivation. SOD is less effective due to its inactivation by ozone. On the other hand, alcohols do not provide significant protection. The data suggest the possible involvement of superoxide radicals in the inactivation of catalase by ozone.

Animals↗