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PubMed1987

Heat and pH dependence of catalase. A comparative study.

Effects of pH and heat were examined on the activity of enzyme catalase from human sources (normal and pathological sera, tissue homogenates, purified catalases). The pH optimum, temperature optimum and T50 values of purified catalases were lower than those of normal, or pathological sera and tissue homogenates. On contrast, the activation energy showed its highest value in purified catalase. These findings might be explained by the post-translational modification of enzyme catalase. The obtained results failed to enhance the diagnostic role of serum catalase determination, nevertheless, gave the optimal values of pH and temperature for catalase assay.

Catalase↗
PubMed1986

Catalase activity in red cell and liver of mice infected with Plasmodium berghei.

Hydrogen peroxide (H2O2) has been incriminated to have an oxidative killing malaria parasite. As P. berghei-infected mouse red cells generated H2O2 in vivo, this would result in the alteration of catalase status of the host. The present study was undertaken to determine catalase activity in red cells and liver of mice infected with P. berghei. The studies were performed in 17 samples of infected red cells as well as 20 samples of the normal red cells. Results showed that the catalase activity in red cells of the infected group was significantly lower (p less than 0.01) than that of the normal group. There was a reverse relationship between catalase activity and parasitemia. Crude parasite lysates possessed no catalase activity. Liver catalase content in the infected group was also found to be significantly lower (p less than 0.05) than that of the control group. All these findings indicated that P. berghei-infected mice caused a depressed catalase activity in red cells and liver which was possibly due to the catalatic function in detoxifying the increased H2O2 to water and free oxygen.

Animals↗
PubMed1985

Quantitative determination of catalase activity produced by Neisseria gonorrhoeae, Staphylococcus epidermidis, Neisseria meningitidis and other bacterial strains using the Catalasemeter.

The conventional catalase test only gives qualitative or semi-quantitative information of the amount of catalase activity produced. Using such a method, we have selected two strong catalase activity producers (Neisseria gonorrhoeae G-10, Staphylococcus epidermidis 66) and a weak producer (Neisseria meningitidis 34702). Quantitative determination of the catalase activity produced by these strains was done by the disk-flotation method using the Catalasemeter. The production of catalase activity in liquid culture by N. gonorrhoeae, S. epidermidis and N. meningitidis occurred mainly during the logarithmic growth phase. The maximum concentration of catalase activity found in these cultures was, for both strong producers, 160 units (U)/ml while it was around 20 U/ml for the weak producer. Some of the other bacteria tested showed high concentrations of catalase activity (130-162 U/ml) and these were: N. gonorrhoeae strain PR 77112 (penicillin resistant), Staphylococcus strain 7 (coagulase negative), Micrococcus sp. strains 2 and 42.

Bacteria↗
PubMed1976

Cytochemical localization of catalase and peroxidase in sinusoidal cells of rat liver.

The cytochemical localization of catalase and peroxidase in various sinusoidal cells of rat liver, i.e., in Kupffer cells, endothelial cells, and fat-storing cells has been investigated. The alkaline 3,3'-diaminobenzidine technique reveals distinct "catalase-positive particles" in all three cell types. The particles are round to oval-shaped, measuring 0.1 to 0.3 mum. in diameter. The diaminobenzidine reaction product is distributed uniformly over their matrix, often obscuring the distinct limiting membrane. In fat-storing cells the particles appear in close proximity of lipid droplets. No evidence of fusion of the limiting membrane of the particles with that of phagolysosomes containing latex particles was observed. The "catalase-positive particles" appeared often in close proximity of endoplasmic reticulum, but by examining consecutive serial sections we could not find any convincing evidence of direct continuity between the two organelles. In addition to catalase there is an endogenous peroxidase in the endoplasmic reticulum and nuclear envelope of Kupffer cells. Whereas peroxidase is sensitive to aldehyde fixation and has its optimal pH in the neutral range, the staining for catalase requires prior fixation with glutaraldehyde and isoptimal at pH 10.5. By using proper fixation and incubation conditions the two enzymes have been visualized selectively, and it is demonstrated that they occupy two distinct intracellular compartments within the Kupffer cells: the catalase in the matrix of particles and the peroxidase in the endoplasmic reticulum. The possible functional role of catalase in various sinusoidal cells is briefly discussed.

Adipose Tissue↗
PubMedDate not supplied

Serological approaches for the characterization of catalase in tissue-derived mycobacteria.

Cell-free extracts of Mycobacterium lepraemurium from mouse liver and M. leprae from armadillo liver were analysed for the presence of any mycobacterial catalase by using the specific inhibitor 3-amino-1,2,4-triazole and seroprecipitation titrations. These studies clearly demonstrated the presence of a "T" type of mycobacterial catalase in M. lepraemurium and placed it, in terms of immunological distance, in a position between M. tuberculosis and M. avium. The results did not reveal any detectable "T" catalase activity in the M. leprae preparations. The "M" type catalase activity which was observed did not bind to antisera against "M" catalase of M. kansasii, but was bound to the extent of 80% to antisera against normal armadillo liver catalase. The significance of the component of the "M" catalase in M. leprae preparations which did not react against antibodies to normal liver remains to be determined.

Amitrole↗
PubMed1993

Cells enriched for catalase are sensitized to the toxicities of bleomycin, adriamycin, and paraquat.

L cells were enriched about 100-fold for catalase by the transcription of the transfected cDNA for human catalase. In spite of substantial enrichment for catalase, the transfected cells (LFN7C/B3) were not resistant to the cytotoxicity of a variety of agents which reduce dioxygen, including paraquat, menadione, adriamycin, phenazine methosulfate, and bleomycin. Instead, they were more sensitive to paraquat, bleomycin, and adriamycin than the untransfected cells from which they derived. Desferrioxamine afforded the cells enriched for catalase modest protection from the toxicities of bleomycin, paraquat, or adriamycin, suggesting that enrichment for iron as a consequence of the increased cellular content of catalase accounted for some of the increased sensitivities. The increased sensitivity of the LFN7C/B3 cells to bleomycin and paraquat was also attributed to the ability of catalase in cells to prevent the drug-induced consumption of O2; by capturing H2O2 before it can escape the cell and converting it to O2, catalase can maintain the concentration of O2 either for repeated rounds of chemical reduction or for direct interaction with the toxin. As predicted by this formulation, the toxicities of paraquat and of bleomycin were increased in an atmosphere of 40% dioxygen in comparison with an atmosphere of 20% dioxygen.

Animals↗
PubMedDate not supplied

[Noncovalent immobilization of catalase on antibodies adsorbed on carbon fabric].

Catalase was immobilized on an immunosorbent prepared by anticatalase adsorption on an activated carbon fabric (ACF), and its kinetic parameters were determined. The immobilized catalase activity depended on the binding capacity of anticatalase. Under the optimum conditions (6 micrograms/mg anticatalase, 5.24 nM catalase) the immobilized catalase activity was 1.5-ford higher as compared to soluble catalase. Antibodies stabilized soluble catalase, but decreased its thermostability on immobilization of immunocomplexes on ACF. Noncovalent immobilization of catalase on adsorbed antibodies opens up the way to the use of this approach for immobilization of other oligomeric enzymes.

Adsorption↗
PubMed1994

Reversals of blood-brain barrier disruption by catalase: a serial magnetic resonance imaging study of experimental optic neuritis.

PURPOSE: To investigate serially the role of catalase detoxification of endogenous H2O2 in the disruption of the blood-brain barrier (BBB) and demyelination of experimental optic neuritis. METHODS: Serial contrast-enhanced magnetic resonance imaging (MRI) of the optic nerves (T1 weighted) and T2 weighted MRI without contrast were performed on 18 guinea pigs 3 to 14 days after sensitization with central myelin for experimental allergic encephalomyelitis. Sex and age-matched littermates were paired and sensitized with the identical antigenic emulsion. To detoxify endogenous hydrogen peroxide (H2O2), animals received daily intraperitoneal injections of polyethylene glycol (PEG)-catalase at a dose of 12,000 U/kg per day for 3 days, then 1,200 U/kg daily for the next week, commencing 3 days after antigenic sensitization. Littermates received an equal volume of preservative-free saline. The intensity of gadolinium-DTPA (Gd-DTPA) enhancement was quantitated by obtaining the value for a region of interest (ROI) of the right optic nerve and the left optic nerve. The effect of H2O2 detoxification by catalase was evaluated by differences in the intensity of Gd-DTPA enhancement and T2 weighted signal in the ROI of the right and the left optic nerves at 7, 10, and 14 days after antigenic sensitization, from the pretreatment value obtained at day 3. The effectiveness of catalase detoxification of H2O2 was assessed with quantitative ultracytochemical localization of electron-dense, H2O2-derived cerium perhydroxide in the optic nerves. RESULTS: With PEG-catalase treatment, mean differences for Gd-DTPA enhancement in the ROI at 7, 10, and 14 days after antigenic sensitization were significantly reduced from the pretreatment values obtained 3 days after antigenic sensitization compared with the comparable interval values for untreated littermates. For T2 weighted signal intensity, only the 7- and 14-day values were significantly less with PEG-catalase compared with values for littermates obtained at comparable intervals. Quantitative ultracytochemical localization of H2O2-derived cerium perhydroxide reaction product revealed significant reductions in the medium number of cerium particle counts of the optic nerve head, sheath, and myelinated retrobulbar nerve. CONCLUSIONS: PEG-catalase reduced H2O2-derived cerium perhydroxide reaction product in the optic nerve but did not eliminate it, reversed disruption of the BBB as measured by Gd-DTPA enhancement, and reduced demyelination and edema as measured by T2 weighted signal intensity, suggesting detoxification of H2O2 as a new treatment strategy for disorders of primary demyelination of the central nervous system.

Animals↗
PubMedDate not supplied

Antioxidant activities and mRNA expression of superoxide dismutase, catalase, and glutathione peroxidase in normal and preeclamptic placentas.

OBJECTIVE: Placental production of lipid peroxides is abnormally increased in preeclampsia. The reason for this is not known, but if placental antioxidant enzymes were deficient, lipid peroxides would increase unchecked. In this study, we measured 1) enzyme activities of superoxide dismutase (CuZn-SOD), catalase, and glutathione peroxidase (GSH-Px) and tissue levels of vitamin E, and 2) mRNA expression of CuZn-SOD, catalase, and GSH-Px in normal and preeclamptic placentas. METHODS: Placental tissues were obtained from normal (n = 16) preeclamptic (n = 12) pregnancies immediately after delivery. Tissue pieces were frozen in liquid nitrogen and stored at -80C until assayed. The enzyme activities of CuZn-SOD, catalase, and GSH-Px and the levels of vitamin E were determined by spectrophotometric assays. Messenger RNA expression of CuZn-SOD, catalase, and GSH-Px was determined by Northern blot analysis. RESULTS: The activities of CuZn-SOD and GSH-Px and the tissue levels of vitamin E were significantly lower in preeclamptic placentas than in normal placentas (CuZn-SOD: 1.13 +/- 0.49 versus 3.71 +/- 0.71 U/mg protein, P < .01; GSH-Px: 0.18 +/- 0.01 versus 0.26 +/- 0.02 U/mg, P < .01; vitamin E: 0.08 +/- 0.01 versus 0.18 +/- 0.01 microgram/mg, mean +/- standard error, P < .001), whereas the activity of catalase was significantly higher (93 +/- 3 versus 83 +/- 2 U/mg, P < .05). Relative mRNA expression of CuZn-SOD and GSH-Px was significantly lower in preeclamptic than normal placentas (P < 0.05), but there was no significant difference for catalase (P > .4). CONCLUSIONS: 1) Activities of CuZn-SOD and GSH-Px and the tissue levels of vitamin E are significantly lower in preeclamptic than in normal placentas. 2) Activity of catalase is significantly higher in preeclamptic than in normal placentas. 3) Messenger RNA expression for CuZn-SOD and GSH-Px is lower in preeclamptic placentas. We speculate that decreased antioxidant activity may result in increased lipid peroxide levels in preeclamptic placentas.

Antioxidants↗
PubMed1977

Studies on rat liver catalase. IX. Role of methionine in polypeptide chain inhibition.

Initiation with methionine of the synthesis of rat liver catalase [EC 1.11.1.6] has been investigated. Analysis of the N-terminal residue of nascent catalase peptides labeled in vivo with injected radioactive amino acids, including [3H]methionine, indicated a remarkably high content of methionine. By fractionating [3H]methionine-labeled nascent catalase according to chain length, it was found that peptides of shorter chain length contained more N-terminal methionine relative to total methionine incorporated. In addition, only a small amount of [3H]methionine was detected as the N-terminal amino acid when newly completed catalase was examined by Edman degradation. These results indicate that the synthesis of liver catalase is initiated with methionine, and suggest the presence of a mechanism for its subsequent removal from the N-terminal position. Catalase was also synthesized in a cell-free system directed by the catalase mRNA, using [3H]Met-tRNAf or [3H]Met-tRNAm. The results obtained in such in vitro experiments were in good agreement with those from in vivo studies, and further showed that the N-terminal methionine was provided by a specific initiator tRNA, i.e. tRNA Met f.

Animals↗
PubMed2004

Properties of a novel periplasmic catalase-peroxidase from Escherichia coli O157:H7.

A subset of catalase-peroxidases are distinguished by their periplasmic location and their expression by pathogens. Kinetic and spectral properties have not been reported for any of these enzymes. We report the cloning, expression, isolation, and characterization of KatP, a periplasmic catalase-peroxidase from Escherichia coli O157:H7. Absorption spectra indicated a mixture of heme states dominated by the pentacoordinate and hexacoordinate high-spin forms. Apparent k(cat) values for catalase (1.8x10(4) s(-1)) and peroxidase (77 s(-1)) activities were greater than those of other catalase-peroxidases. However, apparent K(M) values for H2O2 were also higher (27 mM for catalase and 3 mM for peroxidase). Ferric KatP reacted with peracetic acid to form compound I (8.8x10(3) M(-1) s(-1)) and with CN(-) to form a ferri-cyano complex (3.9x10(5) M(-1) s(-1)) consistent with other catalase-peroxidases. The isolation and characterization of KatP opens new avenues to explore mechanisms by which the periplasmic catalase-peroxidases may contribute to bacterial virulence.

Bacterial Proteins↗
PubMed2001

Purification and characterization of a novel bromoperoxidase-catalase isolated from bacteria found in recycled pulp white water.

A bacterial strain, Pseudomonad EF group 70B, containing a high catalase-like activity was found in process water (white water) from pulp using recycled fibers. The enzyme was purified and characterized, and found to be a hydroperoxidase. The active enzyme has an apparent molecular mass of about 153 kDa with two identical subunits and a pI value of 4.7. It has a rather sharp pH optimum for catalase activity at 6.0 but exhibits catalase, peroxidase and brominating activities over a broad pH range from 4 to 8. It was not inhibited by 3-amino-1,2,4-triazole. Peroxidase-like activity was found when adding o-dianisidine, pyrogallol, guaiacol and 4-aminoantipyrine. Brominating activity was noticed using monochlorodimedone as a substrate. The absorption spectrum exhibited a Soret band at 404 nm. Upon reduction with dithionite the Soret peak decreased and shifted to 436 nm. Pyridine hemochrome spectra indicated the presence of a protophorfyrin IX heme group and the enzyme was inhibited by the known heme ligands cyanide and azide. N-terminal amino acid analysis gave the sequence STEVKLPYAVAGGGTTILDAFPGE, which showed no homology with those of known catalases or peroxidases. It is concluded that the enzyme is a novel type of catalase-peroxidase or, more specifically, a bromoperoxidase-catalase, and that future developments of inhibitors of hydrogen peroxide-degrading activities in white water may be based on this enzyme and other catalase-peroxidases.

Journal Article↗
PubMed2001

The role of distal tryptophan in the bifunctional activity of catalase-peroxidases.

Catalase-peroxidases are bifunctional peroxidases exhibiting an overwhelming catalase activity and a substantial peroxidase activity. Here we present a kinetic study of the formation and reduction of the key intermediate compound I by probing the role of the conserved tryptophan at the distal haem cavity site. Two wild-type proteins and three mutants of Synechocystis catalase-peroxidase (W122A and W122F) and Escherichia coli catalase-peroxidase (W105F) have been investigated by steady-state and stopped-flow spectroscopy. W122F and W122A completely lost their catalase activity whereas in W105F the catalase activity was reduced by a factor of about 5000. However, the mutations did not influence both formation of compound I and its reduction by peroxidase substrates. It was demonstrated unequivocally that the rate of compound I reduction by pyrogallol or o-dianisidine sometimes even exceeded that of the wild-type enzyme. This study demonstrates that the indole ring of distal Trp in catalase-peroxidases is essential for the two-electron reduction of compound I by hydrogen peroxide but not for compound I formation or for peroxidase reactivity (i.e. the one-electron reduction of compound I).

Bacterial Proteins↗
PubMed1984

Maturation of catalase precursor proceeds to a different extent in glyoxysomes and leaf peroxisomes of pumpkin cotyledons.

As an approach to study the mechanism of the microbody transition (glyoxysomes to leaf peroxisomes) in greening pumpkin cotyledons, catalase molecules were purified from the two different types of microbody and their structural properties were compared. The purified glyoxysomal catalase was found to consist of four identical subunits (55 kDa), whereas the leaf peroxisomal catalase contains two different forms of monomeric subunit (55 and 59 kDa). These different catalase species cross-reacted with the rabbit antibody raised against the glyoxysomal enzyme. During gel filtration on an Ultrogel AcA 34 column, the leaf peroxisomal 55-kDa polypeptide eluted slightly faster than the leaf peroxisomal 59-kDa polypeptide. The profile of catalase activities exactly paralleled the elution pattern of the 55-kDa molecules, which indicated that the 59-kDa polypeptide was enzymically inactive. Peptide mapping analysis using Staphylococcus aureus protease V8 showed that the glyoxysomal 55-kDa polypeptide was identical to the leaf peroxisomal 55-kDa species, whereas the leaf peroxisomal 59-kDa polypeptide had a different primary structure from the 55-kDa polypeptide. In an in vitro translation system directed by mRNA isolated from etiolated and green cotyledons, glyoxysomal and leaf peroxisomal catalases were synthesized as the identical 59-kDa polypeptide. From peptide mapping analysis, the in vitro-translated 59-kDa polypeptide was found to have a nearly identical primary structure to that of the leaf peroxisomal 59-kDa species. In vivo pulse-chase labeling experiments using etiolated cotyledons showed the conversion of the 59-kDa polypeptide to the 55-kDa molecular species. The overall results strongly indicate that the 59-kDa polypeptide is a precursor form of catalase in pumpkin cotyledons.

Journal Article↗
PubMed1992

Light dependence of catalase synthesis and degradation in leaves and the influence of interfering stress conditions.

The enzyme catalase (EC 1.11.1.6) is light sensitive and subject to a rapid turnover in light, similar to the D1 reaction center protein of photosystem II. After 3 h of preadaptation to darkness or to different light intensities (90 and 520 mumol m(-2) s(-1) photosynthetic photon flux density), sections of rye leaves (Secale cereale L.) were labeled for 4 h with l-[(35)S]methionine. From leaf extracts, catalase was immunoprecipitated with an antiserum prepared against the purified enzyme from rye leaves. Both incorporation into catalase and degradation of the enzyme polypeptide during a subsequent 16-h chase period increased with light intensity. At a photon flux density of 520 mumol m(-2) s(-1), the apparent half-time of catalase in rye leaves was 3 to 4 h, whereas that of the D1 protein was much shorter, about 1.5 h. Exposure to stress conditions, such as 0.6 m NaCl or a heat-shock temperature of 40 degrees C, greatly suppressed both total protein synthesis and incorporation of the label into catalase and into the D1 protein. Immunoblotting assays indicated that in light, but not in darkness, steady-state levels of catalase and of the D1 protein strongly declined during treatments with salt, heat shock, or translation inhibitors that block repair synthesis. Because of the common property of rapid photodegradation and the resulting dependence on continuous repair, declines in catalase as well as of the D1 protein represent specific and sensitive indicators for stress conditions that suppress the translational activities of leaves.

Journal Article↗
PubMed1986

Changes in the Activity of Catalase (EC 1.11.1.6) in Relation to the Dormancy of Grapevine (Vitis vinifera L.) Buds.

Catalase activity in grapevine (Vitis vinifera L.) buds cv. ;Perlette.' increased to a maximum in October and thereafter decreased within 3 months to less than half its maximal rate. The decrease in catalase activity coincided with the decline in temperature during winter. The rate of sprouting of buds forced at 23 degrees C was negatively related to the activity of catalase. Artificial chilling of grapevine canes at 5 degrees C resulted in a 25% decrease of catalase activity in the buds after 3 days and 31% after 17 days. The activity of catalase increased to the control level only 96 hours after removing canes from 5 degrees C to room temperature. Efficient buddormancy breaking agents, such as thiourea and cyanamide decreased catalase activity to 64 and 50% of the controls respectively, while the activity of peroxidase remained the same under those conditions. A less efficient dormancy breaking agent dinitro-ortho-cresol, did not decrease catalase activity.

Journal Article↗
PubMed1989

Enhanced-peroxidatic activity in specific catalase isozymes of tobacco, barley, and maize.

Separation of catalase isozymes from leaf extracts of three diverse plant species (Nicotiana sylvestris, Zea mays, Hordeum vulgare L.) revealed a distinct isozyme with enhanced peroxidatic activity (30-, 70-, 28-fold over typical catalase, respectively) which constituted 10 to 20% of the total catalase activity. In maize this isozyme is the product of the Cat3 gene, which is expressed only in mesophyll cells (AS Tsaftaris, AM Bosabalidis, JG Scandalios [1983] Proc Natl Acad Sci USA 80: 4455-4459). A mutation in barley reducing levels of peroxisomal catalase (AC Kendall et al. [1983] Planta 159: 505-511) does not reduce the amount of the isozyme with enhanced peroxidatic activity. Similarly, this isozyme is unaffected in dark-grown barley in spite of a 75% decrease in total catalase activity. These results suggest that this catalase isozyme is under separate genetic control in barley. This may also be the case in tobacco where the catalase isozyme with enhanced peroxidatic activity is an immunologically distinct protein (EA Havir, NA McHale [1989] Plant Physiol 89: 952-957).

Journal Article↗
PubMed1984

Protection of Bacillus larvae from Oxygen Toxicity with Emphasis on the Role of Catalase.

Sporulation of Bacillus larvae NRRL B-3650 occurred only at aeration rates lower than those used for cultivation of most Bacillus species. One possible explanation for the requirement for a low level of aeration in B. larvae is that toxic forms of oxygen such as H(2)O(2) and superoxide are involved. The superoxide dismutase levels of strain B-3650 were similar to those of Bacillus subtilis 168 during sporulation, and no NADH peroxidase was present. Catalase activity was absent during exponential growth and first appeared near the start of the stationary phase. The catalase activity was 2,700 times less than that in B. subtilis 168 at the same stage of development. Therefore, the relative deficiency of catalase (and NADH peroxidase) might be the cause of the apparent O(2) toxicity. It was postulated that B. larvae might accumulate H(2)O(2) in the medium and exhibit more than normal sensitivity to H(2)O(2). Experimental results did not verify either postulate, but the possibilities of intracellular accumulation of H(2)O(2) and unusual sensitivity to endogenous H(2)O(2) were not excluded. The catalase present in early-stationary-phase cells was soluble, heat labile, and inhibited by cyanide, azide, and hydroxylamine. An increase in catalase activity also occurred at the time of appearance of refractile spores in both B. larvae NRRL B-3650 and B. subtilis 168. The level of catalase activity in strain B-3650 was 5,400 times less than that in B. subtilis 168 at this stage. In B. larvae, this second increase occurred primarily within the developing endospore. The activity in spore extracts was particulate, heat stable, and inhibited by hydroxylamine but not by azide or cyanide. Synthesis of catalase in B. larvae was unaffected by H(2)O(2), O(2), or glucose.

Journal Article↗