Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.11.1.6 (catalase)
 55,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The enzymatic destruction of oxidizing products produced during metabolic reduction of oxygen in the cell (such as singlet oxygen, H2O2 and OH radical) involves the concerted action of superoxide dismutase-which removes O-2 and yields H2O2-and H2O2 removing enzymes such as catalase and glutathione peroxidase. A difference in distribution or ratio of these enzymes in various tissues may result in a different reactivity of oxygen radicals. It was found that in red blood cells superoxide dismutase and catalase are extracted in the same fraction as hemoglobin, while glutathione peroxidase appears to be "loosely" bound to the cellular structure. This suggests that in red blood cells catalase acts in series with superoxide dismutase against bursts of oxygen radicals formed from oxyhemoglobin, while glutathione & peroxidase may protect the cell membrane against low concentrations of H2O2. On the other hand, catalase activity is absent in various types of ascites tumor cells, while glutathione peroxidase and superoxide dismutase are found in the cytoplasm. However, the peroxidase/dismutase ratio is lower than in liver cells, and this may provide an explanation for the higher susceptibility of tumor cells to treatments likely to involve oxygen radicals.
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PMID:Enzyme defense against reactive oxygen derivatives. II. Erythrocytes and tumor cells. 81 6

Superoxide dismutase, catalase, glutathione peroxidase and NAD(P)H cytochrome c reductase were quantitated in polymorphonuclear leukocytes (PMN) and alveolar macrophages (AM) obtained from guinea pigs exposed up to 90 h to 85% oxygen. PMN and AM were sonicated and separated into a 16,000-g pellet, a 100,000-g pellet, and a 100,00-g supernate. Superoxide dismutase activity increased in both cells within 18 h, persisted for 66 h and decreased by 90 h. The highest rate of increase was in the 100,000-g pellet containing 3.4% of total enzyme activity in PMN but 28% in AM. The enzyme induction in PMN and AM was partially inhibited by daily intracardiac injections of 50 mg/kg actinomycin D. During oxygen exposure, catalase activity in PMN and AM decreased to 60% of its original activity, and gluthathione peroxidase was reduced in PMN to 60% and in AM to 20% of control values. Although NAD(P)H cytochrome c reductase decreased to 50% in PMN, no change was noted in AM. Upon exposure to superoxide anion, purified catalase, the glutathione peroxidase of the 100,000-g supernate, NADH, and NADPH cytochrome c reductases of the 16,000-g pellet decreased to 66+/-5%, 72+/-4%, 52+/-8%, and 40+/-9%, respectively, of their original activity. This inactivation was prevented by 0.1 mg superoxide dismutase. These in vitro observations could explain the decreased catalase and glutathione peroxidase activity demonstrated in vivo that may lead to an intracellular accumulation of hydrogen peroxide. Increased hydrogen peroxide concentrations have been found to inactivate superoxide dismutase thus impairing the first defense mechanism against superoxide anion.
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PMID:The alteration of superoxide dismutase, catalase, glutathione peroxidase, and NAD(P)H cytochrome c reductase in guinea pig polymorphonuclear leukocytes and alveolar macrophages during hyperoxia. 82 33

Late ovarian chambers of Drosophila melanogaster have been examined by ultrastructural cytochemistry in an attempt to characterize some of the transformations which precede the completion of oogenesis. From stage 11 onward peroxidase activity is present in the endoplasmic reticulum of both nurse cells and oocyte, as well as in the egg-covering precursors of the columnar follicle cells. Catalase activity is restricted to the very last stages of oogenesis (stage 13-14) and appears to be located in membrane-bound organelles of the ooplasm which are continuous with the endoplasmic reticulum. Because of the presence of catalase as well as by their structural appearance, these organelles are to be identified as microperoxisomes. Catalase activity becomes cytochemically detectable in the ooplasm somehow in coincidence with the formation of glycogen. Furthermore, glycogen is first formed in intimate association with alpha-1 yolk platelets. On the basis of these findings it is suggested that glycogen synthesis occurs by a process of gluconeogenesis.
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PMID:Cytochemistry of late ovarian chambers of Drosophila melanogaster. 82 30

Uric acid in serum was determined calorimetrically with a batch type microcalorimeter, by measuring the heat evolved during a coupled uricase/catalase enzymic reaction in tris(hydroxymethyl)aminomethane HCl buffer (pH 9.0 at 30 degrees C). Heat evolution and concentration are linearly related through the physiological range of serum uric acid concentrations and the method is free of interferences of the sort encountered with spectrophotometric methods. Precision and accuracy are good (CV, 2%) and the results correlate well with those obtained by a mechanized colorimetric uricase/peroxidase system.
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PMID:Calorimetric enzymic measurement of uric acid in serum. 83 82

Estradiol binds covalently to normal leukocytes during phagocytosis. The binding involves three cell types, neutrophils, eosinophils, and monocytes and at least two reaction mechanisms, one involving the peroxidase of neutrophils and monocytes (myeloperoxidase [MPO]) and possibly the eosinophil peroxidase, and the second involving catalase. Binding is markedly reduced when leukocytes from patients with chronic granulomatous disease (CGD), severe leukocytic glucose 6-phosphate dehydrogenase deficiency, and familial lipochrome histiocytosis are employed and two populations of neutrophils, one which binds estradiol and one which does not, can be demonstrated in the blood of a CGD carrier. Leukocytes from patients with hereditary MPO deficiency also bind estradiol poorly although the defect is not as severe as in CGD. These findings are discussed in relation to the inactivation of estrogens during infection and the possible role of estrogens in neutrophil function.
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PMID:Estrogen binding by leukocytes during phagocytosis,. 85 96

The effect of chilling temperatures on the catalase and peroxidase activities, soluble proteins and chlorophyll contents of excised organs of Pisum sativum plants has been studied. In leaf and stem tissues, storage at 0 degrees C did not bring about any statistically significant variation in the levels of heme enzymes, proteins and chlorophyll during four days. On the contrary, in root tissues catalase activity experimented a statistically significant depression after the onset of cold storage and during the whole treatment, whereas the other parameters remained nearly constant. Results obtained showed the suitability of storing plant material at 0 degrees C for the stabilization of catalase, peroxidase and chlorophyll in leaves and stems, as well as of peroxidase activity in roots.
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PMID:Catalase and peroxidase activities, chlorophyll and proteins during storage of pea plants of chilling temperatures. 87 81

Ultrastructural changes in tobacco mesophyll protoplasts during the first three days of cultvation were studied. Localization of catalase and peroxidase activities in the freshly isolated protoplasts and 2 days after their cultivation was detected by the cytochemical 3,3'-diaminobenzidine method. A conclusion is drawn that the observed changes in the fine structure and localization of the enzymic activity are due to the following processes: reparation of disturbances caused by the isolation procedure, regeneration of the cell wall and rapid dedifferentiation of the initial parenchymatic leaf cells.
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PMID:[Electron microscopic study of protoplasts of mesophyll tobacco. I. Ultrastructural and cytochemical study of tobacco protoplasts at early stages of cultivation]. 91 Feb 96

By reaction of deuteroferriheme (DFH) with peroxo acids, spectroscopically distinct and peroxidatically active deuteroferriheme-peroxide compounds (DPC) are formed. These species closely resemble, and are probably identical with, the species formed by reaction of DFH with H2O2, which has previously been considered to be an analogue of peroxidase compound I. Stopped-flow spectrophotometric titration studies imply: (a) that DPC is formed by reaction of 1.9 +/- 0.2 mol of DFH with 1 mol of peroxo acid; (b) that the spectral change accompanying formation of DPC is independent of the peroxo acid oxidant used. Titration of the oxidizing power of DPC formed with H2O2 implies that submaximal yields of DPC are obtained, a result that could implicate DPC species as analogues of catalase compound I in the catalase action of ferrihemes. Preliminary results suggest that DPC may involve both monomeric and dimeric heme components.
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PMID:Hydroperoxidase activities of ferrihemes: heme analogues of peroxidase enzyme intermediates. 91 51

The effects of dietary vitamin E on the important cellular antioxidant defense systems were studied in rat blood. One-month-old male Sprague-Dawley rats were fed a basal vitamin E-deficient diet and supplemented with either none or 45 ppm vitamin E for 4 months. The activity of glutathione (GSH) peroxidase was decreased significantly (p less than 0.05) in the red blood cells and plasma of vitamin E-deficient rats. The level of GSH in the red cells of vitamin E-deficient rats was also significantly decreased. No detectable GSH was found in the plasma of both groups of animals. The activities of catalase and superoxide dismutase were not significantly altered by the status of dietary vitamin E. Similar results were obtained when 2-month-old male rats were fed the respective diets for 3 months. The results suggest that the decreased levels of GSH and GSH peroxidase in the red cells of animals fed a vitamine E-deficient diet may in part contribute to their increased susceptibility to hemolytic agents.
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PMID:Dietary vitamin E and levels of reduced glutathione, glutathione peroxidase, catalase and superoxide dismutase in rat blood. 91 61

Mycobacterium phlei contains two catalase activities and a single peroxidase activity. The latter is associated with one of the catalases. The single catalase-peroxidase enzyme accounted for 75% of the total catalase activity and was lost upon acquisition of resistance to the antitubercular drug isoniazid (INH). Heat-treated (68 degrees C) wild-type cells showed similar decreases in catalase activity as well as complete loss of peroxidase activity. Catalase activity in the INH-resistant strain of M. phlei (Inh(r)) was unaffected by heating. The heat-sensitive catalase of the wild-type M. phlei was completely inhibited by 0.1 M INH, and Cu(2+) enhanced this inhibitory effect by 100-fold. No inhibition of activity was found with the heat-stable enzyme. Equivalent inhibition of catalase was also observed with nicotinic acid hydrazide and benzoic acid hydrazide. Peroxidase activity was also completely inhibited by any one of the three hydrazides, either INH, benzoic acid hydrazide, or nicotinic acid hydrazide at 10(-3) M. The presence of two catalase activities and the loss of one (catalase-peroxidase) on acquiring INH resistance or heating wild-type cells was confirmed by acrylamide gel electrophoresis of the cell-free extracts.
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PMID:Differentiation of catalases in Mycobacterium phlei on the basis of susceptibility to isoniazid: association with peroxidase and acquired resistance to isoniazid. 92 Dec 49


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