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)

Initiation with methionine of the synthesis of rat liver catalase [EC 1.11.1.6] has been investigated. Analysis of the N-terminal residue of nascent catalase peptides labeled in vivo with injected radioactive amino acids, including [3H]methionine, indicated a remarkably high content of methionine. By fractionating [3H]methionine-labeled nascent catalase according to chain length, it was found that peptides of shorter chain length contained more N-terminal methionine relative to total methionine incorporated. In addition, only a small amount of [3H]methionine was detected as the N-terminal amino acid when newly completed catalase was examined by Edman degradation. These results indicate that the synthesis of liver catalase is initiated with methionine, and suggest the presence of a mechanism for its subsequent removal from the N-terminal position. Catalase was also synthesized in a cell-free system directed by the catalase mRNA, using [3H]Met-tRNAf or [3H]Met-tRNAm. The results obtained in such in vitro experiments were in good agreement with those from in vivo studies, and further showed that the N-terminal methionine was provided by a specific initiator tRNA, i.e. tRNA Met f.
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PMID:Studies on rat liver catalase. IX. Role of methionine in polypeptide chain inhibition. 89 58

Homogenates of Crithidia fasciculata were fractionated by differential centrifugation. Mitochondria were sedimented quantitatively at 10(4) g-min and accounted for approximately 10% of the total recovered protein. Catalase was found exclusively in the supernatant fraction whilst NADH:cytochrome c oxidoreductase and p-nitrophenylphosphatase were found in all the fractions. Zonal centrifugation confirmed that catalase was non-sedimentable. Clean separation of mitochondria was obtained in both high-speed and rate zonal experiments, but no NADH:cytochrome c oxidoreductase activity could be detected in these organelles. Separation of large lysosomal vacuoles which contained p-nitrophenylphosphatase activity was obtained and these were clearly resolved from mitochondria by both high-speed and rate zonal centrifugation.
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PMID:Subcellular fractionation by differential and zonal centrifugation of the trypanosomatid Crithidia fasciculata. 89 63

Catalase activity in leucocytes was found to be half the normal value in hypocatalasemia and extremely low in acatalasemia. Glucose-6-phosphate dehydrogenase activity in erythrocytes was not significantly different between normal, hypocatalasemia and acatalasemia in three families of acatalasemia, but in one family lower activities than normal were found in hypocatalasemia and actalasemia erythrocytes. Other enzyme activities in blood, such as alkaline phosphatase, lactate dehydrogenase, glutamic oxaloacetic and glutamic pyruvic transaminases were not significantly different between normal subjects, hypocatalasemia and acatalasemia.
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PMID:Activities of catalase in leucocytes and glucose-6-phosphate dehydrogenase in erythrocytes of hypocatalasemia and acatalasemia. 91 59

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

Catalase-positive rods of different dimensions, which frequently appeared crystalline by light microscopy, were found to be concentrated along with microbodies and cytoplasmic enzyme in the cells of the striated and extralobular excretory ducts of mouse salivary glands. When an entire mouse submandibular gland and its ducts were excised, fixed, sectioned and incubated for catalase demonstration, the excretory ducts were intensely stained relative to the remainder of the gland. Light microscopic examination of the stained ductal cells revealed particulate catalase in the form of rods and microbodies as well as reactivity due to non-particulate cytoplasmic enzyme. The cytoplasmic enzyme activity was less intense in some ductal epithelial cells (light cells) which were interspersed in mosaic arrangement among those more intensely stained (dark cells). The rods were somewhat more common in the light cells. Although the rods lack a symmetrical definitive crystal habit, their gross conformation and periodic substructure are reminiscent of crystalline catalase. No rods and relatively few peroxisomes were observed in excretory duct cells of germ-free mice although cytoplasmic catalase was abundant. These observations suggest that the catalase in salivary gland duct cells could be related in some way to the protection of the gland or the oral cavity or both against micro-organisms. Alternatively, the enzyme could be involved in the non-thyroidal biosynthesis of iodinated tyrosine derivatives.
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PMID:Catalase in salivary gland striated and excretory duct cells. I. The distribution of cytoplasmic and particulate catalase and the presence of catalase-positive rods. 92 8

Human hemoglobin was characterized as an enzyme in a reconstituted aniline hydroxylase system containing hemoglobin, NADPH, rat liver cytochrome P-450 reductase, aniline and atmospheric O2. This system catalyzed p-aminophenol formation (turnover number 0.2 mol/min/mol of hemoglobin) with an efficiency similar to that which has been reported for either microsomal cytochrome P-450 or cytochrome P-450 solubilized from rat liver. The rate of the reaction was linearly dependent on hemoglobin concentration up to approximately 1 nmol of hemoglobin/ml. This linear range of hemoenzyme concentration is also similar to cytochrome P-450-catalyzed reactions. Unlike the cytochrome P-450 system, the hemoglobin system did not require a lipid cofactor for maximal activity, and much less reductase was needed for maximal activity. Aniline displayed typical Michaelis-Menten saturation kinetics as substrate, and its Km (8 mM) was the same in the absence of presence of the reductase. Catalase essentially completely inhibited p-aminophenol formation in the absence or presence of reductase. In contrast, superoxide dismutase inhibited the reductase-mediated reaction only to a small extent (if at all). No detectable hydrogen peroxide accumulated during the course of the reaction in the absence of catalase. These findings suggested a hypothetical mechanism for hemoglobin-catalyzed hydroxylation of aniline involving a hemoglobin-bound form of hydrogen peroxide (aniline-Hb3+-OOH-) as an intermediate preceding the rate-determining formation of products.
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PMID:Characterization of Enzyme-like activity of human hemoglobin. Properties of the hemoglobin-P-450 reductase-coupled aniline hydroxylase system. 93 94

Catalase-negative vibrios can be isolated in large numbers from the affected intestinal mucosa of pigs suffering from a range of porcine enteropathies in which the mucosa has an adenomatous component. These vibrios cannot be distinguished from strains of Campylobacter sputorum subsp. mucosalis. The resemblance between these bacteria strengthens the case already made on morphological evidence that these enteropathies have a common origin. Catalase-negative vibrios have also been isolated from the mouth and faeces of pigs. Some of these conform to the criteria established for the mucosalis subspecies but others can be differentiated from it. An antigenic analysis shows that strains of the mucosalis subspecies are closely related antigenically, but that differences may allow separation of strains.
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PMID:Studies on Campylobacter sputorum subspecies Mucosalis. 93 48

Osteoarthritis was induced in the rabbit by a single intra-articular injection of 0.1 ml of a 1% solution of papain. Degeneration of the cartilage was studied 3 hours, 1, 3 and 8 days after the injection by transmission electron microscopy (TEM) and quantified by measuring the fixed charge density (FCD) and 35S incorporation into glycosaminoglycans. TEM observations of chondrocytes revealed a close correlation between the development of this experimental degenerative joint disease and human osteoarthritis. The administration of CH3-prednisolone (0.1 mg/kg on the 2nd and 5th days, i.a.), of indomethacin (1 mg/kg per day X 7, i.v.), and of catalase (50,000 IU/kg per day X 7, i.m.) modified the biochemical parameters measured 8 days after the papain injection. The corticoid potentiated the action of papain (fall in GAG content and synthesis). None of the non-steroid anti-inflammatory drugs modified the FCD. On the other hand, the increase of 35S incorporation was low after indomethacin and very high after acetylsalicylic acid. Catalase brought about an almost complete recovery of GAG content, together with an important increase in 35S incorporation. This arthropathy could be widely used in experimental pharmacology as a selective test and as a means of studying the mechanism of action of osteoarthritic drugs.
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PMID:Activity of anti-inflammatory drugs on an experimental model of osteoarthritis. 94 94

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

Colony count cultures and catalase determinations were done on 294 urine samples in two series of patients at Royal Victoria Hospital. Thirty-six specimens were reported to be positive by colony count and by catalase determination. A total of 135 specimens found to be negative by colony count were also negative by the disk flotation test. Catalase activity in 4 urines reported as false negative were found to contain 6,000 or less colonies per ml. More than 50 per cent of the false positive results could be attributed to the presence of red blood cells. Data were insufficient to explain the remaining false positive catalase determinations. However, catalase determinations by the disk flotation method proved to be a successful screening test for significant bacteriuria.
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PMID:Simple screening test for significant bacteriuria in urine. Catalase determination by disk flotation method. 96 74


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