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PubMed1980

Assignment of the gene coding for human catalase to the short arm of chromosome 11.

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.

Animals↗
PubMed1982

Peptide mapping of peroxisomal catalase and its precursor. Comparison to the primary wheat germ translation product.

To investigate possible structural modifications of catalase during its biogenesis and packaging into peroxisomes, we have labeled three species of catalase with [35S]methionine: the wheat germ cell-free translation product, the extraperoxisomal precursor made in vivo in rat liver, and mature peroxisomal catalase. These three species have identical mobilities in sodium dodecyl sulfate polyacrylamide gels, when analyzed separately or in mixtures. Tryptic digestion yields 10 [35S]Met-labeled peptides from each, which are indistinguishable when mapped in two dimensions by electrophoresis and chromatography. Partial proteolyses of the three species in sodium dodecyl sulfate gels yielded identical fragmentation patterns. The primary translation product of catalase was labeled with formyl[35S] methionine; its size was indistinguishable from the subunit of mature catalase. Its radioactivity appeared in dansyl methionine if and only if it was deformylated prior to dansylation. These results demonstrate that within the limits of the methods, catalase undergoes no covalent modification during its uptake into peroxisomes and its subsequent maturation to a tetrameric hemoprotein.

Animals↗
PubMedDate not supplied

[Immobilization of Penicillium vitale catalase on aminoethyl cellulose and properties of the obtained preparations].

Preparations of Penicillium vitale catalase immobilized by aminoethyl cellulose (AE-cellulose) are obtained using two methods: by the enzyme covalent cross-linking with the carrier by glutaric aldehyde and by the covalent binding of catalase to the carrier aminogroups through the carbohydrate enzyme component. A dependence is established for the degree of catalase binding and catalase activity of the immobilized enzyme on the enzyme carrier in immobilization ratio. The optimal enzyme-carrier ratio in both cases is 10 mg of the enzyme per 1 g of the carrier. With such a ratio and binding by means of glutaric aldehyde 9.5 +/- 0.23 mg of protein is added to 1 g of the carrier with the 68.7 +/- 3.45% of the activity preserved, and in binding through the carbohydrate component of catalase 9.2 +/- 0.29 mg/g is added with preservation of 84.7 +/- 4.42% of the activity. Studies in properties of soluble and AE-cellulose immobilized catalase of P. vitale and determination of thermodynamic parameters of inactivation showed that the immobilized enzyme is more stable to the effect of temperature and extreme pH values than the soluble one.

Catalase↗
PubMed1995

A human erythrocyte-derived growth-promoting factor with a wide target cell spectrum: identification as catalase.

We have reported previously that a factor with a molecular weight of 53,000 under SDS-polyacrylamide gel electrophoresis purified from human erythrocyte extracts promoted the growth of a wide variety of cell types from different species, including T cells, B cells, myeloid leukemia cells, melanoma cells, and mastocytoma cells, as well as normal and transformed fibroblast cells. In the present study, amino acid sequence analysis revealed that this factor has homology with human catalase. The purified factor exhibited catalase activity. Catalases derived from human erythrocytes, bovine liver, Aspergillus niger, and recombinant rat liver catalase are all able to promote the growth of cells. Antibody against human catalase absorbed both the growth-promoting activity and the enzyme activity of the purified factor. In addition, treatment of the factor with an irreversible enzyme inhibitor, aminotriazole, resulted in abrogation of both the growth-promoting activity and enzyme activity. These results indicate that the growth-promoting factor is catalase, and its activity is associated with the decomposition of hydrogen peroxide.

Amino Acid Sequence↗
PubMed1994

Importance of catalase in the disposal of hydrogen peroxide within human erythrocytes.

The catalase within normal, intact human erythrocytes was completely inactivated with amino triazole. The rate of 14CO2 evolution, when the cells were subsequently incubated with 14C-labeled glucose, provided a measure of the rate at which NADPH was being oxidized by the glutathione peroxidase/reductase system for the disposal of H2O2. This rate was determined in control cells and in catalase-inactivated cells while the cells were exposed to H2O2, which was generated at various constant and predetermined rates by glucose oxidase. The results indicated that catalase handles approximately half of the generated H2O2. The glutathione peroxidase/reductase mechanism accounted for the other half. These results are in agreement with our earlier findings on erythrocytes of a subject with a genetic deficiency of catalase. However, an unexpected result with the present approach was the finding that the increased dependence on the glutathione peroxidase/reductase mechanism did not occur until greater than 98% of the catalase had been inactivated. The latter observation indicates that catalase and the glutathione peroxidase/reductase system function intracellularly in a manner very different from that previously ascribed to them. An explanation of the findings requires that the two methods of H2O2 disposal function in a coordinated way, such as a sequential action in which the glutathione peroxidase/reductase system is the rate-limiting step.

Catalase↗
PubMedDate not supplied

Catalase against met-Hb excess during oximetries of dilute Hb-A samples.

Functional parameters of diluted Hb-A have been determined before and after addition of catalase and disodium-EDTA to the samples. There are no important differences between the results drawn from catalase added samples and catalase free ones, except for the fact the met-Hb level at pH 7.8 is significantly lower in the samples containing catalase. On the contrary, catalase is almost ineffective against met-Hb at pH 6.8, whereas its activity at pH 7.3 is rather modest. Another limitation is that catalase remains active against met-Hb for not more than 15-20 minutes after addition to the sample, which is just the time necessary for one complete (manual) oximetry.

Catalase↗
PubMed1997

Direct evidence for catalase as the predominant H2O2 -removing enzyme in human erythrocytes.

Decomposition of hydrogen peroxide (H2O2 ) at physiological levels was studied in human erythrocytes by means of a recently developed sensitive H2O2 assay. The exponential decay of H2O2 in the presence of purified erythrocyte catalase was followed down to 10(-9) mol/L H2O2 at pH 7.4. H2O2 decomposition by purified erythrocyte glutathione peroxidase (GPO) could be directly observed down to 10(-7) mol/L H2O2 . No enzyme inhibition was observed at these low H2O2 concentrations. Catalase and GPO activities can be determined separately in a titrated mixture of purified enzymes, which simulates the conditions of H2O2 removal by the erythrocyte. Experiments with fresh human hemolysate allowed us to determine H2O2 decomposition by catalase and GPO using these enzymes in their original quantitative ratio. The different kinetics of these enzymes are shown: H2O2 decomposition by catalase depends linearly on H2O2 concentration, whereas that by GPO becomes saturated at concentrations above 10(-6) mol/L H2O2. Even at very low H2O2 concentrations GPO reaches only approximately 8% of the rate at which catalase simultaneously degrades H2O2. These data indicate an almost exclusive role for catalase in the removal of H2O2 in normal human erythrocytes.

Catalase↗
PubMedDate not supplied

[Antithrombotic effect of catalase and chondroitin sulfate derivatives in arterial damage in rats].

The antithrombotic action of catalase and chondroitin sulfate derivatives was studied on the rat arterial thrombosis induced by treatment of vessel with ferrous chloride solution. The effect of native or chondroitin sulfate modified catalase, as well as the mixture of native catalase and free chondroitin sulfate in ratio which is equal to their content in conjugate was compared in respect to corresponding doses according to active catalase content. The antithrombotic action of conjugate and its component mixture is rather similar with each other and significantly exceeds the effect of native enzyme. The conjugate was the most effective in respect to retarding/prevention of arterial occlusion. The action of catalase preparations was altered the thrombus structure conducting blood stream retention at the low doses used. The directions of further studies of antithrombotic activity for catalase, superoxide dismutase and chondroitin sulfate derivatives were founded.

Animals↗
PubMed2006

Identification of Trp106 as the tryptophanyl radical intermediate in Synechocystis PCC6803 catalase-peroxidase by multifrequency Electron Paramagnetic Resonance spectroscopy.

The reactive intermediates formed in the catalase-peroxidase from Synechocystis PCC6803 upon reaction with peroxyacetic acid, and in the absence of peroxidase substrates, are the oxoferryl-porphyrin radical and two subsequent protein-based radicals that we have previously assigned to a tyrosyl (Tyr()) and tryptophanyl (Trp()) radicals by using multifrequency Electron Paramagnetic Resonance (EPR) spectroscopy combined with deuterium labeling and site-directed mutagenesis. In this work, we have further investigated the Trp() in order to identify the site for the tryptophanyl radical formation, among the 26 Trp residues of the enzyme and to possibly understand the protein constraints that determine the selective formation of this radical. Based on our previous findings about the absence of the Trp() intermediate in four of the Synechocystis catalase-peroxidase variants on the heme distal side (W122F, W106A, H123Q, and R119A) we constructed new variants on Trp122 and Trp106 positions. Trp122 is very close to the iron on the heme distal side while Trp106 belongs to a short stretch (11 amino acid residues on the enzyme surface) that is highly conserved in catalase-peroxidases. We have used EPR spectroscopy to characterize the changes on the heme microenvironment induced by these mutations as well as the chemical nature of the radicals formed in each variant. Our findings identify Trp106 as the tryptophanyl radical site in Synechocystis catalase-peroxidase. The W122H and W106Y variants were specially designed to mimic the hydrogen-bond interactions of the naturally occurring Trp residues. These variants clearly demonstrated the important role of the extensive hydrogen-bonding network of the heme distal side, in the formation of the tryptophanyl radical. Moreover, the fact that W106Y is the only Synechocystis catalase-peroxidase variant of the distal heme side that recovers a catalase activity comparable to the WT enzyme, strongly indicates that the integrity of the extensive hydrogen-bonding network is also essential for the catalatic activity of the enzyme.

Bacterial Proteins↗
PubMed2004

Catalase activity in cerebellum, hippocampus, frontal cortex and striatum after status epilepticus induced by pilocarpine in Wistar rats.

The mechanism underlying the vulnerability of the brain to status epilepticus (SE) induced by pilocarpine remains unknown. Oxidative stress has been implicated in a variety of acute and chronic neurologic conditions, including SE. The present study was aimed at was investigating the changes in catalase activity after pilocarpine-induced seizures and SE. The Control group was treated with 0.9% saline (NaCl, subcutaneously (s.c.)) and sacrificed 1h after the treatment. Another group was treated with pilocarpine (400 mg/kg, s.c., Pilocarpine group) and sacrificed 1h after treatment. The catalase activity in the cerebellum, hippocampus, frontal cortex and striatum of Wistar rats was determined. The results have shown that pilocarpine administration and resulting SE produced a significant increase in the catalase activity in the hippocampus (36%), striatum (31%) and frontal cortex (15%) of treated adult rats. Nevertheless, in the adult rat cerebellum after SE induced by pilocarpine no change was observed in the catalase activity. Our results demonstrated a direct evidence of an increase in the activity of the scavenging enzyme (catalase) in different cerebral structures during seizure activity that could be responsible for eliminating oxygen free radicals and might be one of the compensatory mechanisms to avoid the development of oxidative stress during the establishment of SE induced by pilocarpine. Our reports also indicate clear regional differences in the catalase activity caused by pilocarpine-induced seizures and SE and the hippocampus might be the principal area affected and cerebellum does not modify for this parameter studied during epileptic activity.

Animals↗
PubMed2001

Catalase deficiency reduces survival and pleiotropically affects agronomic performance in field-grown barley progeny.

Field-grown plants of the catalase-deficient mutant RPr79/4 show necrotic lesions in leaves and preferentially die. Initially, necrotic lesions exhibited by RPr79/4 were used to indirectly assess the role of distinct levels of catalase on the survival and agronomic performance of field-grown barley progeny. The segregation of three control traits was also analyzed to eliminate the influence of any obvious meiotic disturbance in case a reduction of plant survival was observed. The RPr79/4 necrotic phenotype had recessive expression in field-grown F1 plants. F2 progeny studies performed in the greenhouse revealed that the inheritance of necrotic lesions was monofactorial, and that the control traits segregated as expected. Progeny test analyses of field-grown F2 plants demonstrated that necrotic homozygous plants died preferentially. While the few surviving necrotic homozygous families were catalase-deficient, healthy homozygous families had normal levels of catalase. Progeny test analyses of the control traits confirmed the inheritance calculated in F2. Taken together, these findings indicate that abnormal segregation of necrotic lesions cannot be attributed to any obvious abnormal meiotic behavior but to the incapacity of catalase-deficient plants to overcome field stress conditions. Thus, catalase deficiency in barley reduced survival and pleiotropically affected the agronomic performance by diminishing seed weight and yield.

Journal Article↗
PubMed2002

New insights into the heme cavity structure of catalase-peroxidase: a spectroscopic approach to the recombinant synechocystis enzyme and selected distal cavity mutants.

Catalase-peroxidases (KatGs) are heme peroxidases with homology to yeast cytochrome cperoxidase (CCP) and plant ascorbate peroxidases (APXs). KatGs exhibit a peroxidase activity of broad specificity and a high catalase activity, which strongly depends on the presence of a distal Trp as part of the conserved amino acid triad Arg-Trp-His. By contrast, both CCP and APX do not have a substantial catalase activity despite the presence of the same triad. Thus, to elucidate structure-function relationships of catalase-peroxidases (for which no crystal structure is available at the moment), we performed UV-Vis and resonance Raman studies of recombinant wild-type KatG from the cyanobacterium SynechocystisPCC 6803 and the distal side variants (His123-->Gln, Glu; Arg119-->Ala, Asn; Trp122-->Phe, Ala). The distal cavity of KatG is very similar to that of the other class I peroxidases. A H-bond network involving water molecules and the distal Trp, Arg, and His is present, which connects the distal and proximal sides of the heme pocket. However, distal mutation not only affects the heme Fe coordination state and perturbs the proximal Fe-Im bond, as previously observed for other peroxidases, but also alters the stability of the heme architecture. The charge of the distal residues appears particularly important for maintaining the heme architecture. Moreover, the Trp plays a significant role in the distal H-bonding, much more pronounced than in CCP. The relevance of these findings for the catalase activity of KatG is discussed in light of the complete loss of catalase activity in the distal Trp mutants.

Bacterial Proteins↗
PubMed1990

The distribution of catalase activity, isozyme protein, and transcript in the tissues of the developing maize seedling.

The catalase activity, CAT-2 and CAT-3 isozyme protein levels, and the steady-state mRNA levels for each of the three catalase genes were determined in the scutellum, root, epicotyl, and leaf of the developing maize (Zea mays L.) seedling. Catalase activity was highest in the scutellum, with 10-fold lower enzyme activity in the leaf and epicotyl. Very low levels of catalase activity were found in the root. The highest levels of CAT-2 protein were found in the scutellum, with about 10-fold lower levels in the green leaf. CAT-2 protein was present in trace amounts early in root development and no CAT-2 protein was detected in the epicotyl. Shortly after germination, CAT-3 protein was present at high levels in both the epicotyl and green leaf. With development, the amount of CAT-3 protein decreased slowly in the epicotyl and rapidly in the green leaf. Low levels of this isozyme were detected in the scutellum and root. The Cat1 transcript accumulated to low levels in all four tissues during the 14 day developmental period. High levels of the Cat2 transcript were found in the scutellum, with moderate levels of the mRNA in the green leaf. The Cat2 transcript levels were very low in the root and epicotyl. While the Cat3 mRNA level in the scutellum was low, high levels of the Cat3 transcript were detected in the root, epicotyl, and leaf. There was a positive correlation between the accumulation of a catalase isozyme and its transcript, indicating that the tissue specificity of maize catalase gene expression was regulated pretranslationally.

Journal Article↗
PubMed1990

Physiological investigations of a tobacco mutant with o(2)-resistant photosynthesis and enhanced catalase activity.

Experiments are described further indicating that O(2)-resistant photosynthesis observed in a tobacco (Nicotiana tabacum) mutant with enhanced catalase activity is associated with decreased photorespiration under conditions of high photorespiration relative to net photosynthesis. The effects on net photosynthesis of (a) increasing O(2) concentrations from 1% to 42% at low CO(2) (250 microliters CO(2) per liter), and (b) of increasing O(2) concentrations from 21% to 42% at high CO(2) (500 microliters CO(2) per liter) were investigated in M(6) progeny of mutant and wild-type leaf discs. The mutant displayed a progressive increase in net photosynthesis relative to wild type with increasing O(2) and the faster rate at 42% O(2) was completely reversed on returning to 21% O(2). The photosynthetic rate by the mutant was similar to wild type in 21% and 42% O(2) at 500 microliters CO(2) per liter, and a faster rate by the mutant was restored on returning to 250 microliters CO(2) per liter. The results are consistent with a lowered release of photorespiratory CO(2) by the mutant because greater catalase activity inhibits the chemical decarboxylation of alpha-keto acids by peroxisomal H(2)O(2). Higher catalase activity was observed in the tip and middle regions of expanding leaves than in the basal area. On successive selfing of mutant plants with enhanced catalase activity, the percent of plants with this phenotype increased from 60% in M(4) progeny to 85% in M(6) progeny. An increase was also observed in the percent of plants with especially high catalase activity (averaging 1.54 times wild type) on successive selfings suggesting that homozygosity for enhanced catalase activity was being approached.

Journal Article↗
PubMed1992

The in Vivo and in Vitro Inhibition of Catalase from Leaves of Nicotiana sylvestris by 3-Amino-1,2,4-Triazole.

Seedlings of tobacco (Nicotiana sylvestris) were treated in vivo with 0.03 to 20 millimolar 3-amino-1,2,4-triazole (aminotriazole). There was a rapid loss of catalase (EC 1.11.1.6) activity over the first 5 hours followed by a slower decrease for the next 4 hours to a level that was 15 to 20% of the initial activity, with little or no change for periods up to 3 days. Fifty percent loss of catalase activity occurred at 0.10 to 0.15 millimolar inhibitor (18-hour incubation). The isozymes of tobacco catalase differed in sensitivity to the inhibitor. Enhanced-peroxidatic catalase (EP-CAT) (Havir EA, McHale NA, [1989] Plant Physiol 91: 812-815) decreased 35% under conditions in which the major isozyme decreased 85%. The resistance to aminotriazole inhibition demonstrated in vivo by EP-CAT was also observed in vitro. The times for 50% inhibition at 0.67, 3.33, 5.0, 10.0, and 15 millimolar aminotriazole were 15, 5, 2.6, 2.5, and 1.5 minutes, respectively, for the major isozyme of catalase and 60, 18.5, 5.1, 4, and 3.0 minutes, respectively, for EP-CAT. Increasing H(2)O(2) concentration did not change the sensitivity of EP-CAT to aminotriazole. The major form of catalase contained 4.0 +/- 0.4 moles of heme per mole enzyme and EP-CAT 3.4 +/- 0.3. Thus, the resistance of EP-CAT to aminotriazole is probably not due to lowered affinity for H(2)O(2) or alteration in heme content but to structural changes that impair inhibitor binding.

Journal Article↗
PubMed2002

Enterococcus faecalis heme-dependent catalase.

Enterococcus faecalis cells cannot synthesize porphyrins and do not rely on heme for growth but can take up heme and use it to synthesize heme proteins. We recently described a cytochrome bd in E. faecalis strain V583 and here report the identification of a chromosomal gene, katA, encoding a heme-containing cytoplasmic catalase. The 54-kDa KatA polypeptide shows sequence similarity to members of the family of monofunctional catalases. A hexahistidyl-tagged version of the catalase was purified, and major characteristics of the enzyme were determined. It contains one protoheme IX group per KatA polypeptide. Catalase activity was detected only in E. faecalis cells grown in the presence of heme in the medium; about 2 and 10 micro M hemin was required for half-maximal and maximal production of catalase, respectively. Our finding of a catalase whose synthesis is dependent on the acquisition of heme in the opportunistic pathogen E. faecalis might be of clinical importance. Studies of cellular heme transport and heme protein assembly and in vivo synthesis of metalloprotein analogs for biotechnological applications are impeded by the lack of experimental systems. We conclude that the E. faecalis cell potentially provides such a desired system.

Bacillus subtilis↗
PubMed1963

THE REVERSION OF CATALASE DURING GROWTH OF YEAST IN ANAEROBIOSIS.

Growth of originally aerobic bakers' yeast under conditions of anaerobiosis caused a decrease in the total specific catalatic activity (patent plus cryptic) of one-half per generation. It is concluded that reversion of catalase was a dilution, rather than a destruction, of the intracellular enzyme. However, the specific patent (whole cell) catalase activity remained constant for one or more generations, and then declined at a considerably slower rate than did the total activity. Thus the cryptic factor diminished progressively during anaerobic growth; after seven or eight generations virtually all the catalase was patent; i.e., the cryptic factor (the ratio of total enzyme to patent enzyme) was approximately unity. At this point, the basal level of enzyme was attained, and thereafter maintained by a basal synthesis, which produced only the patent, heat-stable, variety. Aerobic growth caused a significant, but much smaller, decline of both total catalase activity and of the cryptic factor. The data suggested that during reversion, the cryptic, heat-labile catalase became progressively converted to the patent, heat-resistant form. A model of these events is presented.

Anaerobiosis↗
PubMed1964

CATALASE ACTIVITY IN LEPTOSPIRA.

Rao, P. J. (University of Illinois, Urbana), A. D. Larson, and C. D. Cox. Catalase activity in Leptospira. J. Bacteriol. 88:1045-1048. 1964.-A number of serotypes of Leptospira were found to possess catalase activity, although considerable variation in activity existed among various serotypes. Catalase activity of L. pomona was reduced by inhibitors commonly employed for arresting catalase activity in other biological systems. Catalase activity was increased three to five times by growing cultures under conditions of oxygen availability; however, aeration had no beneficial effect on total viable cell crop. The relationship of oxygen to metabolism and future studies on virulence of the leptospirae is discussed.

Azides↗