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PubMed1987

Catalase has only a minor role in protection against near-ultraviolet radiation damage in bacteria.

In bacterial cells near-ultraviolet radiation (NUV) generates H2O2 which can be decomposed by endogenous catalase to H2O and O2. To assess the roles of H2O2 and catalase in NUV lethality, we manipulated the amount of intracellular catalase (a) by the use of mutant and plasmid strains with altered endogenous catalase, (b) physiologically, by the addition of glucose, and (c) by induction of catalase synthesis with oxidizing agents. Not only was there no direct correlation between NUV-resistance and catalase activity, but in some cases the correlation was inverse. Also, while there was correlation between NUV and H2O2 sensitivity for most strains tested, there were a number of exceptions which indicates that the modes of killing were different for the two agents.

Bacterial Proteins↗
PubMed1986

A prenatal test for the cerebro-hepato-renal (Zellweger) syndrome by demonstration of the absence of catalase-containing particles (peroxisomes) in cultured amniotic fluid cells.

In this paper we show that whereas acyl-CoA: dihydroxyacetone phosphate acyltransferase, a membrane-bound peroxisomal enzyme, is deficient in homogenates of cultured amniotic fluid cells of fetuses with Zellweger syndrome, catalase a soluble peroxisomal matrix enzyme is present in normal amounts. Digitonin titration experiments revealed a striking difference in the percentage of particle-bound catalase in control and Zellweger amniocytes: in Zellweger amniocytes all catalase activity was found to be present in the soluble cytoplasm, (less than 5% particle-bound), whereas in control amniocytes catalase was found to be predominantly particle-bound (62% +/- 8%, n = 5). Measurement of the percentage of particle-bound catalase by means of digitonin titrations thus provides a simple prenatal test for Zellweger syndrome via the direct demonstration of the presence or absence of catalase-containing particles (peroxisomes).

Acyltransferases↗
PubMed1975

Genetic regulation of the expression of catalase activity in murine red blood cells.

The specific activity (k'1) and concentration of red blood cell catalase from four inbred strains of mice (BALB/c, C57BL, C57BL/6, and NBL) were measured to determine the mechanisms responsible for interstrain variations in enzyme activity. The specific activities of RBC catalase in NBL and the C57BL sublines are equal (2.5 x 10(7) M-1 sec-1), while that of BALB/c (4.0 x 10(7) M-1 sec-1) is 67% greater. The relative concentration of catalase is approximately 30% lower in NBL erythrocytes compared to the other three strains. The activity of BALB/c RBC catalase is due to a high k'1 coupled with a high intracellular concentration; RBC catalase activity in the C57BL sublines is the result of a low k'1 and high concentration. A low k'1 and a low concentration are responsible for the low catalase activity levels found in NBL erythrocytes.

Animals↗
PubMed1978

The peroxisome (microbody) membrane: effects of detergents and lipid solvents on its ultrastructure and permeability to catalase.

The effects of detergents, organic lipid solvents, and several adjuvants used in cell fractionation on the ultrastructure of the peroxisomal (microbody) membrane and its permeability to catalase have been investigated. Chopper sections of glutaraldehyde-fixed liver were incubated in the presence of various agents, followed by cytochemical staining for catalase and processed for electron microscopy. Catalase activity was also determined biochemically in the incubation medium. Marked catalase diffusion was found after treatment with 1% or 0.5% Triton X-100 or deoxycholate, as well as with 50% ethanol or acetone or 20% propanol or t-butanol. In contrast, 1% digitonin and lower concentrations of the above agents, as well as sucrose or glycerine caused selective diffusion of catalase from a limited population of peroxisomes. Treatment with 10% polyvinylpyrrolidone (PVP), which has been used as a protective agent in the isolation of microbodies, did not produce any alteration in the fine structure and cytochemical appearance of peroxisomes. These findings concur with earlier biochemical studies on freshly isolated peroxisomes and demonstrate the susceptibility of microbodies, even in glutaraldehyde-fixed rat liver to the effects of various agents which affect the microbody membrane. A close correlation between the ultrastructural integrity of the microbody membrane and its permeability to catalase has been found. The significance of these observations for the assessment of the permeability characteristics of the microbody membrane is discussed.

Animals↗
PubMed1998

Stability and refractoriness of the high catalase activity in the oxidative-stress-resistant fission yeast Schizosaccharomyces pombe.

Effect of oxygen and metabolic substrates (glucose, ethanol) on the catalase activity of anaerobically grown Schizosaccharomyces pombe cells was assessed and compared with that of Saccharomyces cerevisiae in order to determine the catalase activity regulation in S. pombe. In contrast to S. cerevisiae, the total catalase activity of permeabilized S. pombe anaerobically grown cells is higher than that found in aerobically grown cells, is stable and constant under all circumstances (i.e. it is not induced by oxygen and/or substrates), and only a negligible part (3-5%) of it is contributed by de novo protein synthesis during aeration with or without substrates. The patent catalase activity of intact cells rises 2-fold during 6-h aeration without substrate and 7-8-fold in the presence of glucose or ethanol. The increase is not inhibited by cycloheximide and is thus not due to de novo catalase synthesis, but may reflect enhanced transport of catalase to the cell surface or a permeabilization of the plasma membrane during the aeration.

Aerobiosis↗
PubMed1998

Purification and characterization of a catalase from the nonsulfur phototrophic bacterium Rhodobacter sphaeroides ATH 2.4.1 and its role in the oxidative stress response.

When challenged with reactive oxidants, the nonsulfur phototrophic bacterium Rhodobacter sphaeroides ATH 2.4.1 exhibited an oxidative stress response during both phototrophic and chemotrophic growth. Upon preincubation with 100 microM H2O2, catalase activity increased fivefold. Catalase was also induced by other forms of oxidative stress, heat-shock, ethanol treatment, and stationary-phase conditions. Only one band of catalase activity was detected after native and denaturing PAGE. The enzyme was purified 304-fold with a yield of 7%. The purified enzyme displayed a heterodimeric structure with subunits of 75 and 68 kDa, corresponding to a molecular mass of approximately 150 kDa for the native enzyme. The subunits had almost identical amino-terminal peptide sequences, sharing substantial similarity with other bacterial catalases. The enzyme exhibited an apparent Km of 40 mM and a Vmax of 285,000 U (mg protein)-1. Spectroscopic analysis indicated the presence of protoheme IX. The heme content calculated from pyridine hemochrome spectra was 0.43 mol per mol of enzyme. The enzyme had a broad pH optimum and was inhibited by cyanide, azide, hydroxylamine, 2-mercaptoethanol, and sodium dithionite. These data indicate that this catalase belongs to the class of monofunctional catalases.

Amino Acid Sequence↗
PubMed1999

Purification, characterization, and primary structure of a monofunctional catalase from Methanosarcina barkeri.

Methanosarcina barkeri is a strictly anaerobic, cytochrome-containing, methane-forming archaeon. We report here that the microorganism contains a catalase, which was purified and characterized. The enzyme with an apparent molecular mass of 190 kDa was shown to be composed of four identical subunits of apparent molecular mass of 54 kDa. The heme-containing enzyme did not exhibit peroxidase activity, which indicates that it is a monofunctional catalase. This is substantiated by the primary structure, which is related to that of other monofunctional catalases rather than to that of bifunctional catalase-peroxidases. The enzyme showed an [S]0.5V for H2O2 of 25 mM and an apparent Vmax of 200,000 U/mg; it was inhibited by azide ([I]0.5V = 1 microM) and cyanide ([I]0.5V = 5 microM) and inactivated by 1,2,4-aminotriazole. The activity was almost independent of the pH (between pH 4 and 10) and the temperature (between 15 degrees C and 55 degrees C). Comparison of the primary structure of monofunctional catalases revealed that the enzyme from M. barkeri is most closely related to the monofunctional catalase of Dictyostelium discoideum.

Amino Acid Sequence↗
PubMed1999

Cyanamide reduces brain catalase and ethanol-induced locomotor activity: is there a functional link?

The present study was designed in an attempt to assess a previously suggested role of brain catalase activity in ethanol-induced behaviour by examining ethanol-induced locomotor activity in cyanamide-treated mice. Mice were pretreated with IP injections of the catalase inhibitor cyanamide (3.75, 7.5, 15, 30 or 45 mg/kg) or saline. Following this treatment, animals in each group received IP injections of ethanol (0.0, 1.6, 2.4 or 3.2 g/kg) and locomotion was recorded. Several time intervals (0, 5, 10, 15, 20 or 25 h) between the two treatments were also evaluated. Results indicated that cyanamide administration produced a dose-dependent decrease in ethanol-induced locomotor activity that depends on the time between treatments. However, cyanamide did not change spontaneous or d-amphetamine-induced locomotor activity. Moreover, an additive effect of cyanamide and another brain catalase inhibitor, 3-amino-1,2,4-triazole (AT), on the reduction of ethanol-induced locomotor activity was observed. Perfused brain homogenates of mice treated with cyanamide, AT or cyanamide+AT showed a significant reduction of brain catalase activity. The dose and time patterns of both effects were closely related and a significant correlation between them was obtained. These results suggest that cyanamide could reduce locomotor activity through its inhibition of brain catalase, giving further support to the notion that brain catalase may be an important regulator of some ethanol-induced behavioural effects.

Analysis of Variance↗
PubMed1995

Resistance to oxidants associated with elevated catalase activity in HL-60 leukemia cells that overexpress multidrug-resistance protein does not contribute to the resistance to daunorubicin manifested by these cells.

PURPOSE: It has been recognized that enhanced antioxidant defenses can contribute to the resistance of cancer cells displaying multidrug resistance (MDR) that arises in conjunction with the overexpression of P-glycoprotein (Pgp). The purpose of this study was to determine if the defenses against oxidant stress in MDR human leukemia cells (HL-60/AR) that overexpress multidrug-resistance-associated protein (MRP), but not Pgp, contribute to the mechanism of drug resistance in this cell line. METHODS: HL-60/AR cells were evaluated in comparison with wild-type cells with respect to sensitivity to the oxidants hydrogen peroxide (H2O2) and tert-butyl hydroperoxide (t-BuOOH), the activities and amounts of the antioxidant enzymes catalase and glutathione peroxidase (GSH-Px), and the effects that manipulation of the activities of these enzymes may have on cellular sensitivity to the oxidants and to daunorubicin. We also evaluated the ability of the cells to generate daunorubicin semiquinone free radical as measured by electron spin resonance (ESR) spectroscopy. RESULTS: HL-60/AR cells were > 10-fold resistant to the cytotoxic effects of the H2O2 or t-BuOOH as compared with parental, drug-sensitive HL-60 cells. This phenomenon could be attributed largely to elevated activity and protein levels of catalase in HL-60/AR cells. Furthermore, inhibition of catalase by 3-amino-1,2,4-triazole (AT) diminished the resistance of HL-60/AR to these oxidants by > 80% or > 50%, respectively. Despite these findings, AT was incapable of causing sensitization of HL-60/AR cells to the cytotoxic effects of daunorubicin. We found that the activity and amount of selenium-dependent glutathione peroxidase (GSH-Px) was no greater in HL-60/AR cells than in HL-60 cells. Cultivation of cells in selenium-deficient medium caused a marked reduction in GSH-Px activity in HL-60/AR cells and a profound inhibition of GSH-redox cycling manifested by a decrease in baseline hexose monophosphate shunt activity (HMPS) and markedly blunted stimulation of the HMPS by the oxidant t-BuOOH in both wild-type and resistant cells. These variations in GSH-Px activity and GSH-redox cycling, however, were not associated with an alteration in cellular sensitivity to daunorubicin. The failure of catalase inhibition or selenium manipulation of GSH-Px activity to affect daunorubicin cytotoxicity was not due to the inability of these cells to produce free-radical species of daunorubicin, since ESR studies revealed that the generation of daunorubicin semiquinone free radical by HL-60/AR cells was equal to and, in fact, 3-fold that obtained with HL-60 cells. CONCLUSIONS: In comparison with parental HL-60 cells, MRP-overexpressing HL-60/AR cells have demonstrable alterations in antioxidant defenses that are manifested by cellular resistance to the cytotoxic effects of H2O2 and t-BuOOH and by elevated protein levels and activity of catalase. Whether these alterations are epiphenomena or are related to overexpression of MRP remains to be determined. However, it does appear that the enhanced antioxidant defenses observed in HL-60/AR cells do not contribute to the resistance to daunorubicin manifested by this cell line. Although HL-60/AR cells generate daunorubicin semiquinone free radical to an extent equal to or greater than that observed in HL-60 cells, the failure of alterations in GSH-Px activity or inhibition of catalase to change the sensitivity of HL-60/AR cells to daunorubicin suggests that the cytotoxicity of daunorubicin in these cells in not mediated through H2O2 or other peroxide species detoxified by these enzymes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

Catalase, superoxide dismutase, and glutathione peroxidase activities in various rat tissues after carbon tetrachloride intoxication.

BACKGROUND: The aim of this study was to determine the possible relationship between the activity of three different antioxidant enzymes--peroxidase superoxide dismutase, catalase, and glutathione peroxidase--and carbon tetrachloride-induced injury. METHODS: Male Wistar rats weighing 200-250 g were used in the experiments. Rats of the experimental groups were given carbon tetrachloride 0.5 ml/kg i.p. in olive oil (5 mmol/kg body mass) for 1 or 3 days. Control group rats were injected with olive oil only for the same period. Brain, liver, kidney, and heart supernatants were used for measurement of superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPX) activities. RESULTS: No statistically significant changes in SOD and GPX activities were observed in the liver after CCl4 administration, but catalase activity was significantly increased after 24 h and remained at that level during the course of the study. In the brain, SOD and catalase activities decreased after 24 h of experiment, but GPX activity statistically significantly increased at all time points studied. Increased activities of SOD, catalase, and GPX were found in heart after CCl4 intoxication. The CCl4 injection in our experiment caused a reduction of SOD and catalase activities and increased GPX activity in the kidney. CONCLUSIONS: The results suggest that change in antioxidant enzyme activities may be relevant to the ability of the liver and other investigated organs to cope with oxidative stress during CCl4 poisoning.

Animals↗
PubMed2004

Analysis of serum catalase activities in pancreatic diseases.

BACKGROUND: Active oxygen species are thought to be involved in the exacerbation of acute pancreatitis. Therefore, it would be reasonable to speculate that the activity of catalase is increased in the severe form of acute pancreatitis. The aim of the present study was to diagnose the severity of acute pancreatitis, using catalase activity, and to examine the usefulness of this measurement for this diagnosis. METHODS Catalase could be measured quickly in 87 patients with pancreatic disease, using automatic analyzers, and using kits based on UV rate assay methods. RESULTS: In pancreatic disease, catalase activity was higher in acute pancreatitis, particularly in the early stage of the disease. It could be used to diagnose the severity of acute pancreatitis almost as early as the criteria of the Japanese Ministry of Health and Welfare (MHW). When we set 330 U/l as the cutoff value, its sensitivity of diagnosis was 76.9% in the first 4 days of the disease and its specificity was 100%. CONCLUSIONS: As catalase activity can be measured quickly using automatic analyzers, serum catalase activity is useful for evaluation of the severity of acute pancreatitis.

APACHE↗
PubMed2005

Subchronic exposure to high-dose ACE-inhibitor moexipril induces catalase activity in rat liver.

The long-term clinical effects of ACE-inhibitors have similarities with those of both fibrates and glitazones, activators of peroxisome proliferator activator receptor (PPAR) alpha and gamma, respectively. The antioxidant enzyme catalase, a heme protein that degrades hydrogen peroxide, is found at high concentrations in peroxisomes. Catalase activity is one of the recognized surrogate markers indicative of PPAR activation in the rat liver. The purpose of the study was to establish the effect of moexipril on catalase activity and to compare it with the effect of both saline controls and that of the known PPAR agonist clofibrate (positive control). Three groups of seven rats were used. All substances were applied i.p. daily for 5 days, followed by a 2-day break. The cycle was repeated eight times. After the final cycle (day 56) the animals were sacrificed and liver tissue collected. The number of catalase positive cells in both moexipril group (95% CI 57-61) and clofibrate group (95% CI 72-80) is higher than in controls (95% CI 3-16) (p < or = 0.01). The number of catalase positive cells in the clofibrate group is higher than in the moexipril group (p < or = 0.01). High-dose subchronic exposure to the ACE-inhibitor moexipril induces catalase activity in the rat liver to an extent comparable to fibrates. We suggest that some of the long-term advantages of ACE inhibitor use - beyond mere BP lowering - might be due to a PPAR mediated effect.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1992

Mechanisms of cellular resistance to hydrogen peroxide, hyperoxia, and 4-hydroxy-2-nonenal toxicity: the significance of increased catalase activity in H2O2-resistant fibroblasts.

An H2O2-resistant variant (OC14) of the HA1 Chinese hamster fibroblast cell line which demonstrates a 20-fold increase in catalase activity was utilized in the study of mechanisms responsible for cellular resistance to hydrogen peroxide, oxygen, and 4-hydroxy-2-nonenal toxicity. HA1 and OC14 cells were treated with 9 mM aminotriazole which resulted in a 60 to 80% reduction in catalase activity. Pretreatment with aminotriazole resulted in significant sensitization to the toxicity of 1-h exposures to exogenously applied H2O2, which was proportional to the reduction in catalase activity. Treatment with aminotriazole produced significant sensitization to the toxicity of 95% O2 after 45 h of O2 exposure but no sensitization to the toxicity of a 1-h exposure to 50 microM 4-hydroxy-2-nonenal. Inhibition of catalase activity by aminotriazole had no effect on the metabolism of 4-hydroxy-2-nonenal by either cell line tested. These results support the conclusion that in H2O2-resistant cells, catalase activity is a major determinant of cellular resistance to H2O2 toxicity, whereas catalase activity has a limited role in cellular resistance to an acute exposure to 95% O2 and is unrelated to cellular resistance to 4-hydroxy-2-nonenal.

Aldehydes↗
PubMed1992

The reaction of Aspergillus niger catalase with methyl hydroperoxide.

The formation of Compound I from Aspergillus niger catalase and methyl hydroperoxide (CH3OOH) has been investigated kinetically by means of rapid-scanning stopped-flow techniques. The spectral changes during the reaction showed distinct isobestic points. The second-order rate constant and the activation energy for the formation of Compound I were 6.4 x 10(3) M-1s-1 and 10.4 kcal.mol-1, respectively. After formation of Compound I, the absorbance at the Soret peak returned slowly to the level of ferric enzyme with a first-order rate constant of 1.7 x 10(-3) s-1. Spectrophotometric titration of the enzyme with CH3OOH indicates that 4 mol of peroxide react with 1 mol of enzyme to form 1 mol of Compound I. The amount of Compound I formed was proportional to the specific activity of the catalase. The irreversible inhibition of catalase by 3-amino-1,2,4-triazole (AT) was observed in the presence of CH3OOH or H2O2. The second-order rate constant of the catalase-AT formation in CH3OOH was 3.0 M-1 min-1 at 37 degrees C and pH 6.8 and the pKa value was estimated to be 6.10 from the pH profile of the rate constant of the AT-inhibition. These results indicate that A. niger catalase forms Compound I with the same properties as other catalases and peroxidases, but the velocity of the Compound I formation is lower than that of the others.

Animals↗
PubMed1980

Magnetic circular dichroism studies on the electronic configuration of catalase compounds I and II.

Absorption and magnetic circular dichroism spectra of native catalase, compound I and compound II have been measured and the data compared with that observed previously for horseradish peroxidase. The native catalase data at pH 6.9 are characteristic of a high-spin ferric porphyrin and are similar to the data reported for the ferric myoglobin and ferric horseradish peroxidase at pH 7. Oxidation of native catalase by peroxoacetic acid forms the compound I species that is identified by its low absorbance in the 400 nm Soret region and a series of overlapping bands between 450 nm and 680 nm. The magnetic circular dichroism spectra of compound I of catalase closely resembles that previously obtained for horseradish peroxidase compound I. These results indicate that the ground state of the heme pi-system is the same in both catalase and horseradish peroxidase compound I species. The compound II data show that the ratio of the magnetic circular dichroism intensity for the Soret to alpha A terms is 0.5 which means that there is a redistribution of angular momentum between the pi* excited states that give rise to the Soret and alpha-bands compared with the horseradish peroxidase compound II data where the ratio of the analogous A term intensities has a value of about 3. In addition, the magnetic CD spectra of both the catalase and horseradish peroxidase compound II species are reminiscent of typical metalloporphyrin spectra which lack charge-transfer transitions and where the metal d-orbitals are decoupled from the porphyrin pi-system.

Animals↗
PubMed1984

Polyethylene glycol-modified catalase exhibits unexpectedly high activity in benzene.

Bovine liver catalase with molecular weight of 248,000, which consists of four subunits, was modified with 2,4-bis(o-methoxypolyethylene glycol)-6-chloro-s-triazine(activated PEG2). The modified catalase became soluble in organic solvents such as benzene by increasing the degree of modification of amino groups in the enzyme with activated PEG2. The enzymic activity of the modified catalase in benzene, in which 42% of the total amino groups were coupled with the modifier, was unexpectedly high in comparison with the activity of non-modified catalase in aqueous system. The absorption spectrum of the modified catalase in benzene showed the characteristic pattern of a haem protein with Soret band at 405 nm. The temperature-activity profile of the modified catalase in benzene was clarified and its activation energy was estimated to be 1900 cal/mol.

Animals↗
PubMed1987

Parallel inheritance of tissue catalase activity and immunostimulatory action of amphotericin B in inbred mouse strains.

Both amphotericin B (AmB) and its methyl ester derivative are potent immunoadjuvants that also stimulate murine B lymphocytes and macrophages in vitro. Most of the common inbred mouse strains show AmB-induced immunostimulation (AmB-high responders) but mice from the C57BL strains, regardless of H-2 genotype, are AmB-low responders. Lymphoid cells from AmB-high responder strains also exhibit greater resistance to H2O2 toxicity in vitro compared with cells from AmB-low responders. This result led to an evaluation of differences in the tissue catalase levels of AmB-high and -low responder strains. Results from several laboratories, including ours, indicate that C57BL mouse strains express low levels of tissue catalase activity in addition to low or absent immunostimulant effects of AmB. Several AmB-high responder strains have high spleen cell, macrophage, and liver catalase, and the mouse strain distribution of enzyme activity as well as the dominant inheritance of the low catalase phenotype is compatible with regulation by the Ce-1 locus in lymphoid organs as well as liver. Other evidence also suggests that H2O2 metabolism is important in lymphoid cell responses to AmB. For example, AmB stimulates a stronger respiratory burst in macrophages from AmB-high responder strains under the same conditions that inhibit burst activity in macrophages from low responders. Selective immune enhancement by AmB in high catalase mouse strains along with enhanced susceptibility to AmB toxicity in low responder C57BL mice with low tissue catalase activity suggests that cellular peroxidation is a major determinant of the genetic regulation of amphotericin-induced immunostimulation.

Amphotericin B↗
PubMed1992

The isolation and partial characterization of catalase and a peroxidase active fraction from human white adipose tissue.

1. A procedure is described for the purification of catalase and a peroxidase active fraction from human white adipose tissue. 2. Gel electrophoresis on SDS-PAGE revealed relative molecular masses of 202,900 and 208,600 for the active catalase and peroxidase molecules respectively (nonreducing conditions), as compared to 56,800 and 49,800 for the monomers under reducing conditions, thus indicating the likelihood of tetramers in the intact state. 3. The two purified enzymes differ with regard to pH optima (5-9 for catalase and 3 for peroxidase), temperature stability (up to 50 degrees C for catalase and 70 degrees C for peroxidase) and Km values towards H2O2 (38.9 mM for catalase and 7.69 mM for peroxidase, which was also active in oxidizing a number of o-dihydricphenols as second substrates). 4. The catalase enzyme showed uncompetitive inhibition by the irreversible inhibitor 3-amino-1,2,4-triazole (AT), Ki = 5.4 mM.

Adipose Tissue↗