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)

Normal erythrocyte catalase, the enzyme present in the blood of Swiss acatalasemic heterozygotes, and their hybrid produced in vitro, were studied after crosslinking with bifunctional reagents. On theoretical grounds [cf. Hajdu, J., Bartha, F. & Friedrich, P. (1976) Eur. J. Biochem. 68, 373--383] it is inferred from the dodecylsulphate gel electrophoretic patterns obtained after treating catalase with diimidates of various chain lengths that the enzyme is an isologous tetramer (D2 symmetry). The minimal distances between crosslinkable primary amino groups across the three domains of bonding are different. Reaction with diimidates causes a moderate loss of enzyme activity in all three enzyme types due to amidination rather than crosslink formation. On the other hand, crosslinking stabilizes the enzyme against urea and heat inactivation. This is most prominent with heterozygote acatalasemic catalase. Crosslinking markedly prevents the development of peroxidase activity that can be elicited in catalases by urea treatment. The role of the quaternary structure of the protein in the relationship between catalase and peroxidase activities is discussed.
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PMID:Properties of human erythrocyte catalases after crosslinking with bifunctional reagents. Symmetry of the quaternary structure. 92 73

Endogenous peroxidase activity, as demonstrated by the technique of Graham and Karnovsky (Graham RC Jr, Karnovsky MJ: J Histochem Cytochem 14:291, 1966), was identified in medullary collecting tubule cells and in the cells of renal papillary mucosa of the rat. Peroxidase reactive sites were observed in the perinuclear cisterna, endoplasmic reticulum, and cytoplasmic vesicles of such cells. The specificity of the peroxidase reaction was verified by means of chemical inhibitors (NaN3, KCN, aminotriazole), denaturation of the enzyme by heat, exclusion or prior oxidation of substrate (diamino-benzidine), and high concentration of H2O2. Prolonged fixation (glutaraldehyde) improved cellular detail but diminished or abolished the peroxidase staining. When exogenous H2O2 was excluded from the incubating medium, a positive reaction was obtained suggesting that H2O2 can be endogenously generated. This observation was confirmed by degradation of tissue-formed H2O2 with beef liver catalase and by blocking endogenous generation of H2O2 with sodium pyruvate. These studies indicate that the reaction product is the result of an enzymatic reaction and that the enzyme is most likely a peroxidase. A similar staining reaction was not observed in other tubule segments, including cortical collecting tubules. The significance of this peroxidase activity is discussed in relation to the cellular localization and biosynthesis of renal medullary prostaglandins.
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PMID:Cytochemical localization of endogenous peroxidase activity in renal medullary collecting tubules and papillary mucosa of the rat. 94 31

Resonance Raman spectra of oxidized hydroperoxidases are examined for shifts in the structure-sensitive, anomalously polarized bands; these are found, respectively, at 1576, 1567 and 1570 cm-1 in the high-spin resting enzymes: horse radish peroxidase, horse blood catalase, and cytochrome c peroxidase. In compound II of horse radish peroxidase and horse blood catalase, and in the enzyme-substrate complex of cytochrome c peroxidase, this band appears at 1587-1590 cm-1 and indicates the iron atom is now in-plane with the porphyrin ring. Weak Raman scattering found with horse radish peroxidase I is consistant with a porphyrin eta-cation radical formulation.
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PMID:Laser Raman spectra of oxidized hydroperoxidases. 94 50

Because of the many potent biological capabilities of the blood granulocytes, and their contact with platelets in various physiologic and pathologic states, a possible interaction between granulocytes and platelets was investigated. Platelets were purified by gel filtration and via a dialysis membrane were separated from suspensions of autologous granulocytes prepared by dextran sedimentation and resuspended in modified Tyrode's buffer. After 20 min at 37 degrees C platelet aggregation was shown to be diminished by such exposure, as compared to the aggregation of platelets incubated with dialysates of buffer only. When granulocytes were stimulated by the addition of 1.1-muM latex spheres as target particles for phagocytes, the dialysate of these cells exhibited greatly enhanced platelet-inhibitory properties. The addition of catalase to the platelets abolished the effect of exposing these cells to the dialysate of resting granulocytes and markedly inhibited the effect of exposing the platelets to the dialysate of phagocytosing granulocytes. Catalase treated with 3-amino-1,2,4-triazole had no platelet-protective capacity. Purified suspensions of lymphocytes released no platelet-inhibitory principle under these experimental conditions. Hydrogen peroxide in the dialysate of granulocytes was measured directly with an assay involving an H2O2-induced decrease in the fluorescence of scopoletin catalyzed by horseradish peroxidase. The dialysate of phagocytosing granulocytes contained 0.86 +/- 0.55 nmol H2O2/2.5 X 10(7) granulocytes when sampled at 20 min. By an alternate measurement technique in which scopoletin and horseradish peroxidase were present in the dialysate from time zero, the mean amount of H2O2 in the dialysate reached 4.0 +/- 1.3 nmol/2.5 x 10(7) granulocytes at 20 min. This discrepancy suggested the consumption of H2O2, possibly mediated by the granulocytes themselves. This possibility was investigated by the addition of exogenous H2O2 to the test system. Both granulocytes and platelets enhanced the disappearance of H2O2 from the dialysate, and the amount consumed was proportional to the amount of H2O2 added to the system. Glucose oxidase at 12 M U/ml plus glucose in excess resulted in the production of H2O2 at a rate and final amount comparable to that produced by phagocytosing granulocytes. This mixture, when substituted for phagocytosing granulocytes in the standard dialysis membrane experiment, induced an inhibition of platelet aggregation similar to that caused by the granulocytes. The observation that the release of H2O2 by the blood granulocyte influences platelet function suggests a potential role for the granulocyte in the regulation of hemostasis or thrombosis.
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PMID:Leukocyte-platelet interaction. Release of hydrogen peroxide by granulocytes as a modulator of platelet reactions. 94 61

In sheep hepatocytes catalase activity was demonstrated both within peroxisomes and within the cytosol. In the cytosol the catalase reaction product is contiguous to the plasma membrane and surrounds the nuclei, rough endoplasmic reticulum, cisternae, mitochondria and Golgi apparatus. This is the first cytochemical demonstration of guine extraperoxisomal catalase. No catalase reaction product was seen in the cytosol of nonparenchymal cells. To demonstrate catalase, both glutaraldehyde and formaldehyde fixation were used, followed by a diaminobenzidine technique modified from Novikoff and Goldfischer. Control reactions were performed to distinguish catalase reaction product from adsorption of oxidized diaminobenzidine and from precipitate due to oxidase-, peroxidase- or heat-stable peroxidatic activities. The results were evaluated in the light and electron microscopes.
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PMID:Cytochemical demonstration of extraperoxisomal catalase. I. Sheep liver. 95 Apr 58

A long-term administration of retinol in a dose exceeding 15-fold the diurnal requirement to rats weighing 170-200 g provoked a diminution of the erythrocytes resistance to an acid hemolytic, an intensified uptake of glucose, and increased activity of glycolytic enzymes (hexokinase, aldolase, phosphohexoisomerase), accumulation of lactate, along with changes in the redox enzymes activity, suppression of the catalase and intensification of peroxidase activity. The content of microergic nucleotides and electrolites (Na+ and K+) remained unchanged.
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PMID:[Effect of long-term vitamin A administration on the acid fastness and biochemical properties of erythrocytes]. 96 79

The synthesis of several types of antibiotics was investigated in four strains of violet-pigmented bacteria belonging to the species Alteromonas luteo-violaceus. Two of the strains simultaneously produce an antibiotic polyanionic polysaccharide, weakly bound to the cells and diffusing throughout the medium, and two intracellular brominated bactericidal substances. The third strain only synthesizes the polyanionic antibiotic. The fourth one is totally inactive. The macromolecular antibiotic, probably responsible for the autointoxication of the bacteria in their cultures, acts at the respiratory level; it induces an increase of oxygen uptake and the production of peroxides by test bacteria. Thus, its activity is inhibited by catalase and peroxidase.
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PMID:Antibacterial activity of marine violet-pigmented Alteromonas with special reference to the production of brominated compounds. 97 9

The distribution of oestrogen-induced peroxidase in the resuspended 8000g pellet of rat uterine homogenates was examined by centrifugation in a sucrose density gradient. Within 10h of treatment with oestradiol, peroxidase activity was found in a region devoid of catalase or urate oxidase (peroxisomal markers) which did not overlap the fractions containing succinate dehydrogenase (mitochondrial marker) or acid phosphatase (lysosomal marker). The induced uterine enzyme was localized in reticular membrane-bound vesicles with isopycnic density of 1.28g/ml from which it could be released by treatment with detergent.
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PMID:Subcellular localization of oestrogen-induced uterine peroxidase. 100 53

The behaviour of some enzymatic activities, such as monoamino oxidase (MAO), diamino oxidase (DAO), catalase, peroxidase and creatin chinase (CPK) have been studied both in blood serum and myocardial tissue of acute infarcted dogs (obtained by coronary occlusion). The most significant results are the changes of the DAO activity (--50% from the control) and peroxidase activity (+60%), 6 hours after acute ischemia. The effect of reperfusion was studied 2 hours later. A recovery of DAO activities was shown, while the peroxidase activities stayed elevated. All the enzymatic activities studied were evaluated in the serum, under the same experimental conditions. An increase of all these activities was observed until 6th hour of coronary occlusion. The reperfusion of acute ischemia, after six hours, causes a further increase of CPK and MAO activities and a decrease of catalase peroxidase and particulary evident DAO activities. The results of this experiment show that reoxygenation, under our experimental conditions, increases a further enzymatic release and in part causes a metabolic recovery of heart muscle.
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PMID:[Experimental revascularization of acute myocardial infarction. II: Activity of various oxidoreductive tissutal and serum enzymes (author's transl)]. 101 Jan 98

The study on the embryotrophic action of phosalon insecticide preparation is conducted against the background of its comprehensive and thorough hygiene-toxicologic assay. Pregnant white rats undergo treatment per os with 1/10 and 1/100 LD50 throughout the entire gravidity period. Recordings are made of the quantity of corpora lutea, pre- and postimplantation lethality; the pedigree development is traced up to the end of the second postnatal month with readings being made of weight and length in the first postnatal day, presence or not of external malformations, weight increase and survival up to the end of the lactation period, day of eye cleft opening and hairing, and sex ratio. The presence of phosalon and phosalon-oxone in whole embryo homogenates is estimated. Enzyme activity of GOT, GPT, catalase, LDH, G-6-PD, RNA and DNA quantity are studied in the liver of newborns on the second postnatal day. Within 21 days of birth, the peripheral blood picture and visceral weight coefficient are also studied. Investigation of the peripheral blood picture, activity of catalase, GOT and GPT in the liver and serum, alkaline and acid phosphatase, and peroxidase in the serum is performed at the end of the second month. The results point to the presence of an embryotoxic effect at the level of the investigated hepatic indicators, detected on the 2nd day of the postnatal period, only at 1/10 LD50 dose.
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PMID:[Embryotropic action of phosalone]. 103 14


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