Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anaerobically grown Escherichia coli accumulate active manganese-containing superoxide dismutase (MnSOD) upon exposure to diamide. This induction requires de novo biosynthesis of MnSOD. Catalase, glutathione disulfide reductase, and glucose-6-phosphate dehydrogenase were also induced by diamide in anaerobic E. coli. A GSH-negative strain of E. coli did not produce MnSOD under anaerobic conditions and was as responsive to diamide as was the wild type strain. Diamide which had been prereduced, by incubation with GSH, was ineffective. NO3- plus paraquat, which elicits increased anaerobic biosynthesis of the MnSOD polypeptide, but not of active MnSOD, synergized with diamide in the induction of active MnSOD. A similar increase in the ability of diamide to cause anaerobic biosynthesis of active MnSOD was seen when the production of the MnSOD polypeptide was increased by isopropyl-beta-D-thiogalactopyranoside, in a strain bearing the MnSOD gene under the control of the tac promoter. These results are explained in terms of a dual action of diamide, i.e. at both the transcriptional and the maturational levels of biosynthesis of MnSOD. Oxidative inactivation of an Fe(II)-containing repressor and oxidative facilitation of insertion of manganese, in place of iron, into the nascent MnSOD polypeptide, are the postulated bases of this dual action.
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PMID:Anaerobic biosynthesis of the manganese-containing superoxide dismutase in Escherichia coli. Effects of diazenedicarboxylic acid bis(N,N'-dimethylamide) (diamide). 225 40

We have investigated the hepatic effect of ciprofibrate, a potent peroxisomal proliferator, in 9 strains of mice to ascertain whether all strains show similar peroxisome proliferation or if there are any that are resistant to the induction of peroxisome proliferation. Dietary feeding of ciprofibrate at 2 concentrations (0.0125% or 0.025% w/w) for 2 weeks resulted in a significant increase in liver weight (170 to 200%) and a 7- to 11-fold increase in volume density of peroxisomes. Catalase and peroxisomal beta-oxidation enzymes increased by 1.7- to 2.7- and 1.9- to 9.3-fold, respectively, over the controls. SDS-polyacrylamide slab gel electrophoresis of post-nuclear fractions of livers showed a marked increase in 80,000-mol. wt. polypeptide. Immunocytochemical studies, as expected, revealed higher levels of PBE. Ciprofibrate treatment also induced hepatic DNA synthesis in all strains as determined by [3H]thymidine incorporation and autoradiography. Dot blot analysis of total RNA from livers of ciprofibrate-treated mice (5 strains) showed a significant increase in peroxisomal enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase bifunctional enzyme (PBE) mRNA. When the 9 strains were ranked for each parameter, CBA/Ca was the least responsive mouse strain and the B6C3F1 was the most responsive. However, the results of this study indicate that there is no significant interstrain difference in rankings across strains to ciprofibrate-induced hepatic pleiotropic response.
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PMID:Comparison of the peroxisome proliferator-induced pleiotropic response in the liver of nine strains of mice. 274 33

The effects of sodium-(E)-3-(4-(3-pyridylmethyl)phenyl)-2-methyl propenoate (OKY-1581) and (E)-3-(4-(imidazolylmethyl)phenyl)-2-propenoic acid (OKY-046), potent inhibitors to thromboxane A2 synthetase, on peroxisomal beta-oxidation and on lipid levels of liver and serum in the rat were studied. When the animals were administered with OKY-1581 at the dose levels of 100 and 500 mg/kg body weight for 2 weeks, the activity of peroxisomal beta-oxidation increased 2.2- and 6.3-fold respectively. Catalase activity increased 1.3-fold, whereas D-amino acid oxidase (DAAO) and urate oxidase activities did not change. Carnitine acetyltransferase and carnitine palmitoyltransferase activities also increased 2.2- - 4.1-fold and 2.7- - 4.2-fold respectively. These changes of the enzymes related to lipid metabolism were also confirmed by the results of a cell fractionation study. Moreover, the induction of peroxisome proliferation-associated polypeptide having a molecular weight of 80000, which is a bifunctional enzyme in the peroxisomal beta-oxidation system was also observed electrophoretically in the light mitochondrial fraction of the liver of OKY-1581-treated rat. The contents of triglyceride and cholesterol in the serum decreased. These results indicated that the action of OKY-1581 in enhancing hepatic peroxisomal-oxidation is similar to that of a potent hypolipidemic peroxisome proliferator such as clofibrate. On the other hand, differing from OKY-1581, OKY-046 at the dose level of 500 mg/kg for 2 weeks showed no effect on serum and liver lipid levels and on the activities of the peroxisomal enzymes, including a cyanide-insensitive fatty acyl-CoA oxidizing system and carnitine acetyl transferase.
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PMID:Hypolipidemic effect and enhancement of peroxisomal beta-oxidation in the liver of rats by sodium-(E)-3-(4-(3-pyridylmethyl)phenyl)-2-methyl propenoate (OKY-1581), a potent inhibitor of TxA2 synthetase. 357 15

A cDNA library, complementary to mRNAs of alkane-grown Candida tropicalis, was screened by differential DNA dot-blot hybridization with [32P]cDNA reverse-transcribed from mRNA of alkane-grown cells or from cells in which peroxisome formation was repressed by growth on glucose. 9% of the library encodes alkane-induced sequences. The cell-free translation products of eight hybrid-selected mRNAs were characterized by SDS-polyacrylamide gel electrophoresis and fluorography: most of them are probably peroxisomal proteins. Among these, a catalase clone was identified by immunoprecipitation of the translation product with anti-catalase. The clone was sequenced: the inferred amino acid sequence is homologous to the carboxytermini of mammalian and Saccharomyces cerevisiae catalases. C. tropicalis catalase mRNA is 1.7-1.8 kb long by Northern analysis, of which 1.5-1.6 kb is required to code for the 57 kDa polypeptide. Catalase mRNA (assayed by dot-blot hybridization) is strikingly induced in C. tropicalis by growth on alkanes, suggesting that peroxisome induction is transcriptionally regulated. This sublibrary of alkane-induced, mostly peroxisomal clones, together with a recently developed cell-free peroxisome protein import assay, will permit investigation of the targeting of proteins to peroxisomes.
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PMID:Isolation of cDNA clones coding for peroxisomal proteins of Candida tropicalis: identification and sequence of a clone for catalase. 358 Mar 73

The activities of a number of lipid-metabolizing and subcellular marker enzymes were measured in total homogenates and subcellular fractions prepared from the livers of male rats fed diets containing 0.05, 0.1, 0.3, and 0.5% of the hypolipidemic drug tiadenol, resulting in mean drug intake of 45, 90, 330, and 530 mg/day/kg body wt, respectively. In the total homogenates, a massive induction of palmitoyl-CoA hydrolase and peroxisomal palmitoyl-CoA oxidation accompanied by increased free CoASH and long-chain acyl-CoA content was observed at the highest dose levels whereas little change occurred up to 90 mg/day/kg/body wt. The palmitoyl-CoA synthetase activity increased slightly up to 90 mg/day/kg body wt, but higher doses resulted in decreased enzyme activity. Catalase activity increased with the dose to be elevated by a factor of approximately 1.6 at 330 mg/day/kg, whereas the activities of urate oxidase decreased. The specific activities of palmitoyl-CoA hydrolase and peroxisomal palmitoyl-CoA oxidation increased in all fractions, but most markedly in the cytosol. The changes in the activities and the distribution of subcellular marker enzymes and the increase of the peroxisome-associated polypeptide (PPA-80) are in keeping with a peroxisome proliferating effect resulting in formation of premature organelles with altered properties. Since high doses of many hypolipidemic drugs produce hepatic tumors and peroxisomal proliferation in rodents and since no increase in peroxisomes is found in human liver after therapeutic use of lower doses, the dose-response relationship is of interest for the evaluation of the toxicology of this class of agents.
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PMID:Enzymatic changes in rat liver associated with low and high doses of a peroxisome proliferator. 614 26

Rat liver microsomes catalyzed the oxidative delta 6-desaturation of linoleoyl-CoA (C18: 2, delta 9.12.) to gamma-linolenoyl-CoA (c18: 3, delta 6.9.12.) by using molecular oxygen and NADH or NADPH as the electron donors. The antibodies against cytochrome b5 inhibited markedly the delta 6-desaturation in the intact microsomes of the rat liver, suggesting that cytochrome b5 participated in the delta 6-desaturation. These experimental results led us to the hypothesis that the delta 6-desaturation of linoleoyl-CoA followed the scheme. (See formula in text). Terminal "delta 6-desaturase" was purified from rat liver microsomes for the first time by Triton X-100 solubilization, DEAE-cellulose, CM-Sephadex and cytochrome b5-Sepharose chromatography using its high affinity for cytochrome b5. The final enzyme preparation was homogeneous when applied to sodium dodecyl sulfate disc gel electrophoresis. delta 6-desaturase appeared as a single polypeptide of 66,000 daltons containing 49% nonpolar amino acid residues and one atom of non-heme iron. We confirmed that delta 6-desaturase differed from delta 9-desaturase, which converted stearoyl-CoA to oleoyl-CoA. The delta 6-desaturase activity required NADH (or NADPH), linoleoyl-CoA, oxygen, lipid or detergent and three enzymes, such as NADH-cytochrome b5 reductase (or NADPH-cytochrome P -450 reductase), cytochrome b5, and delta 6-desaturase. The reconstituted system of these components also confirmed the electron flow represented in Scheme 1. The delta 6-desaturase activity was inhibited by iron chelators, cyanine and p-chloromercuriphenyl sulfonate. In the reconstituted system of Km value for linoleoyl-CoA was 47 micro M, the maximal velocity was 83nmol/min/mg protein of delta 6-desaturase and the optimal pH was 7.0. Catalase, superoxide dismutase and t-butanol showed supportive effects on the delta 6-desaturation of the reconstituted system when purified enzymes were employed.
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PMID:[Purification and characterization of Linoleoyl-CoA desaturase from rat liver microsomes (author's transl)]. 726 18

The ultrastructure and cytochemistry of megakaryocytes from two patients with a familial gray platelet syndrome are described. Although the Golgi zones appeared normally developed, the megakaryocytes lacked alpha-granules. Catalase-containing particles were normal in number. In immature megakaryocytes, granules measuring from 0.05-0.1 mu and having an electron-dense core occurred in the Golgi area. These granules, which are considered as the precursors of alpha-granules in normal megakaryocytes, appeared unable to mature, and their number decreased with the megakaryocyte maturation. The presence of dense material in distended demarcation membranes and/or vacuoles suggested that their content was discharged. It is suggested that myelofibrosis present in the bone marrow from these two patients may be related to the possible excretion of a polypeptide growth factor normally contained in the alpha-granules. Megakaryocytes grown by the plasma clot procedure from blood precursors isolated from the two patients also did not exhibit alpha-granules, which were replaced by vacuoles. Our findings suggest that the lack of alpha-granules in gray platelets may be related to a defective megakaryocyte-committed cell, and evidence is presented which suggests that the precursors of alpha-granules are produced but that their contents are then lost.
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PMID:Defective alpha-granule production in megakaryocytes from gray platelet syndrome: ultrastructural studies of bone marrow cells and megakaryocytes growing in culture from blood precursors. 746 53

A purification scheme is described for the glyoxylate cycle enzyme malate synthase from maize scutella. With our procedure, large amounts of extremely pure enzyme can easily be prepared. Purification involves a heat denaturation step, followed by ammonium sulfate precipitation, and chromatography on DEAE-cellulose and Blue Dextran-Sepharose. Catalase and malate dehydrogenase, which are the most persistent contaminants, are completely removed by this procedure. Maize malate synthase is an octameric protein with a subunit molecular weight of 64 kDa. Purity of the enzyme preparation was demonstrated by SDS-polyacrylamide gel electrophoresis and by isoelectric focusing (pI = 5.0). Pure malate synthase can be stored without appreciable loss of activity at -70 degrees C in 200 mM Hepes buffer containing 6 mM MgCl2 and 2 mM 2-mercaptoethanol, pH 7.6. Maize malate synthase contains no covalently linked carbohydrate residues. The enzyme requires Mg2+ ions for activity. From circular dichroism measurements we estimate that the secondary structure of the enzyme consists of 30% alpha-helical and almost no (5%) beta-pleated sheet segments. A 45-kDa polypeptide, which contaminates malate synthase preparations if the purification starts from seedlings older than 2.5 days, is shown to be a degradation product of malate synthase. Together with full-length chains, these 45-kDa polypeptides are able to take part in octameric oligomer formation.
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PMID:Purification of the glyoxylate cycle enzyme malate synthase from maize (Zea mays L.) and characterization of a proteolytic fragment. 828 48

Catalase, a peroxisomal marker enzyme in the liver of most mammals, is found by immuno-electron microscopy in guinea pig (GP) hepatocytes not only in peroxisomes, but also in the cytoplasm (Beier et al. (1988) Eur. J. Cell Biol. 46, 129-135). We have been able to distinguish in GP liver homogenates between the cytosolic catalase and that part of the enzyme activity which is due to leakage of the enzyme from peroxisomes by adding 4% polyethylene glycol to the homogenization medium. This approach revealed that approximately 40% of the total catalase activity and almost all of alpha-hydroxy-acid oxidases are peroxisomal, while 60% of catalase is of genuine cytosolic origin. The cytosolic and peroxisomal catalases of guinea pig were purified to homogeneity and were analyzed by SDS-PAGE and isoelectric focussing. The cytosolic catalase exhibited a slightly higher Mr (approximately 1000) and a less acidic pI than the peroxisomal enzyme. Limited proteolysis and amino-acid analysis revealed also slight differences between the two molecular forms of catalase. Total RNA was isolated from guinea pig liver and translated in vitro by using a rabbit reticulocyte lysate system. Immunoprecipitation with an antibody against guinea pig catalase followed by high-resolution polyacrylamide gel electrophoresis revealed two polypeptide bands differing slightly in Mr. These observations suggest strongly, that cytoplasmic and peroxisomal catalases in guinea pig liver are two closely related but distinct proteins.
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PMID:Cytoplasmic and peroxisomal catalases of the guinea pig liver: evidence for two distinct proteins. 865 28

Catalase is an important protective enzyme against H2O2 toxicity. Here, we report the characterization of a Xanthomonas oryzae pv. oryzae catalase gene (katX). The gene was localized and its nucleotide sequence was determined. The gene codes for a 77-kDa polypeptide. The deduced katX amino acid sequence shares regions of high identity with other monofunctional catalases in a range of organisms from bacteria to eukaryotes. The transcriptional regulation of katX was atypical of bacterial monofunctional kat genes. Northern (RNA) analysis showed that katX transcription was highly induced by treatments with low concentrations of menadione, a superoxide generator, and methyl methanesulfonate, a mutagen. It was only weakly induced by H2O2. Unlike in other bacteria, a high level of catalase in Xanthomonas spp. provided protection from the growth-inhibitory and killing effects of H2O2 but not from those of organic peroxides and superoxide generators. Unexpectedly, heterologous expression of katX in Escherichia coli was both growth phase and temperature dependent. Catalase activity in E. coli kat mutants harboring katX on an expression vector was detectable only when the cells entered the stationary phase of growth and at 28 degrees C. The patterns of transcription regulation, heterologous expression, and physiological function of katX are different from previously studied bacterial kat genes.
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PMID:Heterologous growth phase- and temperature-dependent expression and H2O2 toxicity protection of a superoxide-inducible monofunctional catalase gene from Xanthomonas oryzae pv. oryzae. 865 57


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