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PubMed1990

Further studies on o(2)-resistant photosynthesis and photorespiration in a tobacco mutant with enhanced catalase activity.

The increase in net photosynthesis in M(4) progeny of an O(2)-resistant tobacco (Nicotiana tabacum) mutant relative to wild-type plants at 21 and 42% O(2) has been confirmed and further investigated. Self-pollination of an M(3) mutant produced M(4) progeny segregating high catalase phenotypes (average 40% greater than wild type) at a frequency of about 60%. The high catalase phenotype cosegregated precisely with O(2)-resistant photosynthesis. About 25% of the F(1) progeny of reciprocal crosses between the same M(3) mutant and wild type had high catalase activity, whether the mutant was used as the maternal or paternal parent, indicating nuclear inheritance. In high-catalase mutants the activity of NADH-hydroxypyruvate reductase, another peroxisomal enzyme, was the same as wild type. The mutants released 15% less photorespiratory CO(2) as a percent of net photosynthesis in CO(2)-free 21% O(2) and 36% less in CO(2)-free 42% O(2) compared with wild type. The mutant leaf tissue also released less (14)CO(2) per [1-(14)C]glycolate metabolized than wild type in normal air, consistent with less photorespiration in the mutant. The O(2)-resistant photosynthesis appears to be caused by a decrease in photorespiration especially under conditions of high O(2) where the stoichiometry of CO(2) release per glycolate metabolized is expected to be enhanced. The higher catalase activity in the mutant may decrease the nonenzymatic peroxidation of keto-acids such as hydroxypyruvate and glyoxylate by photorespiratory H(2)O(2).

Journal Article↗
PubMed1992

Factors affecting expression of enhanced catalase activity in a tobacco mutant with o(2)-resistant photosynthesis.

Tobacco (Nicotiana tabacum) mutants with 40 to 50% more catalase activity than wild type show O(2)-resistant photosynthesis under conditions of high photorespiration. More than 90% of the population of mutant plants of an M(7) and M(8) generation had enhanced catalase activity, and nearly 40% had activities >3 standard deviations above the mean of wild type. Superoxide dismutase activity was the same in mutant and wild-type leaves. The greater photosynthetic rate of mutant leaves previously observed in the laboratory was confirmed with field-grown plants that showed significantly higher rates (8%) than wild type during 8 days of measurements during a 19-day period of active growth. The tip region of expanding mutant leaves had higher catalase activity than the base of the lamina, and photosynthesis was O(2) resistant in 42% O(2) in the tip compared with the base, thus further supporting the hypothesis that there is a biochemical linkage between these traits. Plants grown in high light (270 micromole photons per square meter per second) had greater catalase activity and an activity ratio of mutant to wild type of 1.45 compared with 1.22 for those grown in low light (130 micromole photons per square meter per second). After acclimation for 3 weeks, plants transferred from low to high light showed increasing activities, and after 5 days the activity ratio of mutant to wild type was the same as in plants acclimated in higher light. The role of enhanced catalase activity in reducing photorespiratory CO(2) is discussed.

Journal Article↗
PubMed1999

Characterization of a facultatively psychrophilic bacterium, vibrio rumoiensis sp. nov., that exhibits high catalase activity

A novel facultatively psychrophilic bacterium, strain S-1, which exhibits extraordinarily high catalase activity was isolated from the drain pool of a fish product processing plant that uses H2O2 as a bleaching and microbicidal agent. The catalase activity of the isolate was 1 or 2 orders of magnitude higher than those of Corynebacterium glutamicum, Staphylococcus aureus, Pseudomonas fluorescens, and five other species tested in this study. The strain seemed to possess only one kind of catalase, according to the results of polyacrylamide gel electrophoresis of the cell extract. The optimum temperature for catalase activity was about 30 degreesC, which was about 20 degreesC lower than that for bovine catalase activity. Electron microscopic observation revealed that the surface of the microorganism was covered by blebs. Although the isolate was nonflagellated, its taxonomic position on the basis of physiological and biochemical characteristics and analysis of 16S rRNA sequence and DNA-DNA relatedness data indicated that strain S-1 is a new species belonging to the genus Vibrio. Accordingly, we propose the name Vibrio rumoiensis. The type strain is S-1 (FERM P-14531).

Journal Article↗
PubMed2000

Cloning, expression, and characterization of the katG gene, encoding catalase-peroxidase, from the polycyclic aromatic hydrocarbon-degrading bacterium Mycobacterium sp. strain PYR-1.

A 81-kDa protein from Mycobacterium sp. strain PYR-1 was expressed in response to exposure of the strain to the polycyclic aromatic hydrocarbon pyrene and recovered by two-dimensional gel electrophoresis. The N-terminal sequence of the protein indicated that it was similar to catalase-peroxidase. An oligonucleotide probe designed from this sequence was used to screen a genomic library of Mycobacterium sp. strain PYR-1, and a positive clone, containing a part of the gene encoding the 81-kDa protein, was isolated. A gene-walking technique was used to sequence the entire gene, which was identified as katG for catalase-peroxidase. The deduced KatG protein sequence showed significant homology to KatGII of Mycobacterium fortuitum and clustered with catalase-peroxidase proteins from other Mycobacterium species in a phylogenetic tree. The katG gene was expressed in Escherichia coli to produce a protein with catalase-peroxidase activity. Since the induction of this catalase-peroxidase occurred in pyrene-induced cultures and the exposure of these cultures to hydrogen peroxide reduced pyrene metabolism, our data suggest that this enzyme plays a role in polycyclic aromatic hydrocarbon metabolism by strain PYR-1.

Bacterial Proteins↗
PubMed1997

Catalase-peroxidase of Caulobacter crescentus: function and role in stationary-phase survival.

Caulobacter crescentus is an obligate aerobe which is exposed to high concentrations of photosynthetic oxygen and low levels of nutrients in its aquatic environment. Physiological studies of oxidative and starvation stresses in C. crescentus were undertaken through a study of lacZ fusion and null mutant strains constructed from the cloned 5' end of katG, encoding a catalase-peroxidase. The katG gene was shown to be solely responsible for catalase and peroxidase activity in C. crescentus. Like the katG of Escherichia coli, C. crescentus katG is induced by hydrogen peroxide and is important in sustaining the exponential growth rate. However, dramatic differences are seen in growth stage induction. E. coli KatE catalase and KatG catalase-peroxidase activities are induced 15- to 20-fold during exponential growth and then approximately halved in the stationary phase. In contrast, C. crescentus KatG activity is constant throughout exponential growth and is induced 50-fold in the stationary phase. Moreover, the survival of a C. crescentus katG null mutant is reduced by more than 3 orders of magnitude after 24 h in stationary phase and more than 6 orders of magnitude after 48 h, a phenotype not seen for E. coli katE and katG null mutants. These results indicate a major role for C. crescentus catalase-peroxidase in stationary-phase survival and raise questions about whether the peroxidatic activity as well as the protective catalatic activity of the dual-function enzyme is important in the response to starvation stress.

Bacterial Proteins↗
PubMed1993

Pseudo infantile Refsum's disease: catalase-deficient peroxisomal particles with partial deficiency of plasmalogen synthesis and oxidation of fatty acids.

Zellweger syndrome, neonatal adrenoleukodystrophy, and infantile Refsum's disease are genetic disorders characterized by the virtual absence of catalase-positive peroxisomes and a general impairment of peroxisomal functions. Recent studies in these three disorders have provided morphologic evidence of peroxisomal "ghosts" of density 1.10 g/cm3 that contain membrane proteins but lack a majority of the matrix enzyme activities. We report here the biochemical studies in a female infant with clinical features of infantile Refsum's disease whose liver and fibroblasts contained cytosolic catalase but no catalase-positive peroxisomes. Oxidation of phytanic and pipecolic acids was severely impaired, whereas oxidation of very-long-chain fatty acids and dihydroxyacetone phosphate acyltransferase activity were only partially decreased. Immunoblot analysis showed that the three peroxisomal beta-oxidation enzymes (acyl-CoA oxidase, enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase, and 3-ketoacyl-CoA thiolase) were detectable in liver tissues. The 3-ketoacyl-CoA thiolase was of the mature form (41 kD), in contrast with other peroxisomal disorders with multiple enzyme deficiencies. The majority of these peroxisomal enzyme activities were associated with two subcellular membrane vesicle fractions lacking catalase: one had the density of normal peroxisomes (1.17 g/cm3), the other, yet undescribed, a lower density (1.137 g/cm3). This suggests that peroxisomes (density = 1.17 g/cm3) and structures with lower density (density = 1.137 g/cm3) found in this patient's cultured skin fibroblasts, although lacking catalase, contained functional peroxisomal enzymes. This distinguishes this disorder from other disorders of peroxisome biogenesis.

Acatalasia↗
PubMedDate not supplied

Genotoxicity of bleomycin in human cell lines differing in catalase activity.

The influence of catalase on the genotoxic effect of bleomycin (BLM) has been evaluated in three cell lines which differ in catalase activity. CRL1307, cells from Xeroderma pigmentosum patient and CLV102, normal embryonic cells have catalase activity 3.5 and 5 times lower then CRL2088, normal skin fibroblasts. Genotoxicity of BLM (0.5-50 micrograms/ml, 2 h treatment) measured with in vitro micronucleus test did not differ in three tested lines. BLM at concentration range from 1 to 25 micrograms/ml (2 h treatment), tested in comet assay, caused similar degree of DNA damage in CLV102 and CRL2088 cells. Exogenous catalase (300 and 900 u/ml) added to the assay medium with BLM did not influence the micronuclei induction. The absence of endo- and exogenous catalase influence on BLM genotoxicity suggests that not hydrogen peroxide but other reactive oxygen species are formed in reaction of activated BLM with molecular oxygen.

Antibiotics, Antineoplastic↗
PubMed1997

Decreased catalase activity in malformation-prone embryos of diabetic rats.

The risk for congenital malformation is increased in diabetic pregnancy. An excess of radical oxygen species (ROS) in the embryo has been suggested as a major teratogenic mechanism. We have used 2 rat strains, denoted H and U, with different catalase isoenzymes to study if the type of ROS scavenging enzyme may be of importance for the embryonic dysmorphogenesis in diabetic pregnancy. Rats were mated H x H and U x U, and about half of the females had streptozotocin-induced diabetes. Embryos were harvested from female rats on day 11 and day 20 of pregnancy. On day 11, the H embryos showed larger crown-rump length (3.9 mm) than the U embryos (2.9 mm), a difference that remained in the embryos of diabetic rats (3.1 mm and 2.5 mm in the H and U strains, respectively). H embryos displayed higher activity of catalase (1.8 +/- 0.1 U/micrograms DNA) than U embryos (1.1 +/- 0.1 U/micrograms DNA), and the difference increased further when the H and U mothers were diabetic (H: 2.1 +/- 0.2 U/micrograms DNA, U: 0.6 +/- 0.1 U/micrograms DNA). In the day-20 fetuses, diabetes in the mother caused increased resorption rate in both strains (from 3.2% to 10.6% in H rats, from 6.8% to 39.5% in U rats), and high rate of congenital malformations in the U strain (H: 0% malformations, U: 20% malformations). We found a strain-related difference in embryo catalase activity with higher activity in the teratogenically resistant H embryos compared to the malformation-prone U embryos. Provided that this difference between the strains signifies a genetic difference of functional antioxidative importance, the results may suggest that catalase enzyme activity has a protective role in opposing embryonic dysmorphogenesis in diabetic rat pregnancy.

Abnormalities, Drug-Induced↗
PubMedDate not supplied

In vitro inhibition of catalase activity by cigarette smoke: relevance for oxidative stress.

The in vitro effects of cigarette smoke on catalase activity were investigated in biological preparations from rat liver and brain using a polarographic method. In both cases cigarette smoke solutions showed a potent ability to inhibit catalase activity with a slight time dependency. The reversibility of their inhibitory activity was demonstrated by in vitro dialysis tests. The catalase inhibitory compound(s) are formed in the smoking process, are not extracted with organic solvents and appear to have a relatively low molecular weight. We also examined the effects obtained by using two different commercial blends of tobacco, achieving a major inhibition with Burley tobacco in comparison to Bright tobacco. These data suggest that the cytotoxic and mutagenic effects of cigarette smoke may be mediated by its additional capacity to enhance the generation of free radicals by inhibiting catalase activity, thus contributing to cell damage particularly during oxidative stress.

Animals↗
PubMed1993

Alterations of hepatocellular peroxisomes in patients with cancer. Catalase cytochemistry and morphometry.

BACKGROUND: Hepatic catalase activity is decreased in patients with malignant diseases, but little is known about the organelles that contain the bulk of catalase: the peroxisomes. METHODS: The authors studied the hepatocellular peroxisomes in patients with malignant diseases by means of catalase cytochemistry, light and electron microscopic study, and morphometry. RESULTS: Under the light microscope, a decrease in catalase staining was observed in 21 of 39 patients with extrahepatic tumors. A peculiar perinuclear concentration of peroxisomes was seen by light microscopic study in 15 of 39 patients and reflected an increase in number in most patients. In one of two hepatoma livers, peroxisomes also showed this perinuclear configuration. Ultrastructural and morphometric analysis of 20 livers of patients with extrahepatic tumors revealed a decreased mean peroxisomal diameter and an increase in number. Electron microscopic study also showed peroxisomes with transparent matrical spots, cytoplasmic invaginations, protrusions, and gastruloid cisternae. In each liver, at least one of these changes was observed. In hepatoma livers, one-third of the peroxisomes revealed empty matrical spots. In one patient, peroxisomes were smaller but more numerous. CONCLUSIONS: Alterations of the peroxisomal compartment are constant findings in the livers of patients with malignant diseases, but individual differences in peroxisomal alterations are frequent.

Adolescent↗
PubMed1979

Immobilized glucose oxidase--catalase and their deactivation in a differential-bed loop reactor.

Glucose oxidase containing catalase was immobilized with a copolymer of phenylenediamine and glutaraldehyde on pumice and titania carrier to study the enzymatic oxidation of glucose in a differential-bed loop reactor. The reaction rate was found to be first order with respect to the concentration of limiting oxygen substrate, suggesting a strong external mass-transfer resistance for all the flow rates used. The partial pressure of oxygen was varied from 21.3 up to 202.6 kPa. The use of a differential-bed loop reactor for the determination of the active enzyme concentration in the catalyst with negligible internal pore diffusion resistance is shown. Catalyst deactivation was studied, especially with respect to the presence of catalase. It is believed that the hydrogen peroxide formed in the oxidation reaction deactivates catalase first; if an excess of catalase is present, the deactivation of glucose oxidase remains small. The mathematical model subsequently developed adequately describes the experimental results.

Catalase↗
PubMed1989

Regulation of catalase-specific mRNA and its processing during development in mice.

This study deals with the pattern of developmental expression of the catalase gene in mice. We have used a mouse catalase 2 kb cDNA (pMCT-1) and its 1.4 kb 5' fragment as probes to characterize the transcripts during embryonic development and differentiation. Total RNA was isolated from 8 days postconceptus (p.c.) whole embryos and from livers and carcasses of 13, 15, and 18 day p.c. embryos as well as from the livers of newborn and adult mice of the S.W. strain. The RNA was applied on slot blots, and run on agarose gels to generate northern blots. Blots were hybridized with the 32P-labeled cDNA probe under different stringency conditions. Autoradiograms were scanned with a densitometer to quantify relative hybridization signals of RNA samples obtained from two or three individual mice representing each stage of development. The catalase transcript is detectable as early as 8 days p.c. with the beginning of somite formation. At this stage, it is primarily in the form of a 12.2 kb transcript. One additional band (2.4 kb) is also apparent at this stage although at a very low intensity. The intensity of the two bands increases with development, particularly during 13-18 days p.c. in liver and carcass. The 2.4 kb RNA band increases sharply from day 8 through 13, 15, and 18 days p.c. and is confined primarily to the liver. Interestingly, only the 2.4 kb RNA band is seen at and after birth. The 2.4 kb RNA is the known mature message of the catalase gene in mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Catalase inhibits nitric oxide synthesis and the killing of intracellular Leishmania major in murine macrophages.

Mouse peritoneal macrophages activated with interferon-gamma (IFN-gamma) and lipopolysaccharide produce substantial amounts of nitric oxide (NO), which correlates with the elimination of the intracellular protozoan parasite Leishmania major. Both the production of NO and the leishmanicidal function of the activated macrophages can be significantly inhibited by catalase in a dose- and time-dependent manner. These results could not be interpreted by the reduction of H2O2 by catalase since the removal of H2O2 by the addition of glutathione peroxidase had no effect on the NO synthesis or the leishmanicidal function of activated macrophages. Furthermore, catalase did not affect the induction of NO synthase in IFN-gamma-activated macrophages. In contrast, the inhibition of NO synthesis and leishmanicidal activity by catalase was reversed in a dose-dependent manner by the addition of tetrahydrobiopterin, a cofactor of NO synthase. Taken together, these results not only further support the central role of NO as the cytotoxic moiety, but also suggest that hydrogen peroxide may interfere with NO production by affecting the levels of cofactor needed for its synthesis.

Animals↗
PubMed1988

Isoelectric focusing of catalase from acatalasemic mouse and human blood, and cultured human skin fibroblasts.

Hemolysates of normal, heterozygous hypocatalasemic and acatalasemic mice and of Japanese acatalasemic subjects were separated into three fractions, A, B and C, by DEAE-cellulose column chromatography, and pI values of A, B and C fractions were determined by isoelectric focusing. The pI value of catalase in the A, B and C fractions increased in the order of normal, hypocatalasemic and acatalasemic mouse blood. The results obtained from Japanese acatalasemic blood samples showed that the pI values of catalase in the A, B and C fractions were similar to those in normal blood. Catalase in Japanese acatalasemic cultured skin fibroblasts was also analyzed by isoelectric focusing. The pI values of catalase in the extract from the cultured skin acatalasemic fibroblasts was similar to that in normal fibroblasts.

Acatalasia↗
PubMed2003

High-resolution structure and biochemical properties of a recombinant Proteus mirabilis catalase depleted in iron.

Heme catalases are homotetrameric enzymes with a highly conserved complex quaternary structure, and their functional role is still not well understood. Proteus mirabilis catalase (PMC), a heme enzyme belonging to the family of NADPH-binding catalases, was efficiently overexpressed in E. coli. The recombinant catalase (rec PMC) was deficient in heme with one-third heme and two-thirds protoporphyrin IX as determined by mass spectrometry and chemical methods. This ratio was influenced by the expression conditions, but the enzyme-specific activity calculated relative to the heme content remained unchanged. The crystal structure of rec PMC was solved to a resolution of 2.0 A, the highest resolution obtained to date with PMC. The overall structure was quite similar to that of wild-type PMC, and it is surprising that the absence of iron had no effect on the structure of the active site. Met 53 close to the essential His 54 was found less oxidized in rec PMC than in the wild-type enzyme. An acetate anion was modeled in an anionic pocket, away from the heme group but important for the enzymatic reaction. An alternate conformation observed for Arg 99 could play a role in the formation of the H-bond network connecting two symmetrical subunits of the tetramer.

Acetates↗
PubMed1995

A 3' untranslated region of catalase mRNA composed of a stem-loop and dinucleotide repeat elements binds a 69-kDa redox-sensitive protein.

Rat lung extract contains protein that forms redox-sensitive, specific complexes with a 1130-base catalase cRNA (J. Biol. Chem. 267, 2853-2855, 1992). The present paper reports studies aimed at delimiting the site of protein binding on the RNA and characterizing the protein. A 240-base sequence was identified as the 3' untranslated region of catalase mRNA that binds lung protein in a redox-sensitive manner. Two elements within this 240-base region bind protein; one is a 36-base element that has a computer-predicted stem-loop secondary structure and the other is a CA dinucleotide repeat. Competition studies indicate that both elements are required for specific binding. Cross-competition experiments demonstrated that catalase RNA-binding protein (CAT-BP) is not the iron-responsive element-binding protein. Ultraviolet light-induced cross-linking and two-dimensional electrophoresis showed that CAT-BP has an apparent molecular mass of 69 kDa and appears to be composed of four isoforms. Competition studies indicate that stem-loop cis element is directly involved in binding CAT-BP. In addition to rat, the 69-kDa catalase RNA-binding protein is present in mouse and human fibroblast cell lines.

Animals↗
PubMed1999

Purification and cloning of a thermostable manganese catalase from a thermophilic bacterium.

We have purified a heat-stable catalase from a thermophilic bacterium, Thermus species strain YS 8-13. The enzyme was purified 160-fold from crude cellular extracts and possessed a specific activity of 8000 units/mg at 65 degrees C. The purified enzyme displayed the highest activity at pH 7 to 10 and temperatures around 85 degrees C. The catalase was determined to be a manganese catalase, based on results from atomic absorption spectra and inhibition experiments using sodium azide. The enzyme was composed of six identical subunits of molecular weight 36,000. Amino acid sequences determined from the purified protein were used to design oligonucleotide primers, which were in turn used to clone the coding gene. The nucleotide sequence of a 1.4-kb fragment of Thermus sp. YS 8-13 genomic DNA containing a 909-bp open reading frame was determined. The gene encoded a 302-residue polypeptide of deduced molecular weight 33,303. The deduced amino acid sequence displayed a region-specific homology with the sequences of the manganese catalase from a mesophilic organism, Lactobacillus plantarum.

Amino Acid Sequence↗
PubMed2001

Catalase-like oxygen production by horseradish peroxidase must predominantly be an enzyme-catalyzed reaction.

When hydrogen peroxide (H2O2) was provided as the only substrate for horseradish peroxidase C (HRP-C) the catalase-like emission of oxygen gas was observed. The reaction was favored at neutral compared to acidic pH. Addition of the superoxide radical scavengers tetranitromethane (TNM) or superoxide dismutase (SOD) increased activity. TNM's effect was concentration dependent but SOD's was not, indicating that only some of the superoxide generated was released into solution. Manganous ions (Mn2+) react with superoxide radicals to regenerate H2O2 but not oxygen; when added to the reaction medium oxygen production was reduced but not abolished. The effect was essentially concentration independent, suggesting that most oxygen was produced enzymatically and not by chemical disproportionation of superoxide. The catalase-like activities of some site-directed mutants of HRP-C suggest that active site residues histidine 42 and arginine 38 are influential in determining this activity. A clear correlation also existed between catalase activity and the enzymes' resistance to inactivation by H2O2. Computer simulation of a reaction scheme that included catalase-like activity agreed well with experimental data.

Arginine↗