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)

When suddenly exposed to air the growth of the obligate anaerobic bacterium of the bacteroidaceae type, strain B6, continues for a few hours before coming to a complete stop. When air is shut off soon after growth has ceased, the organism is able to reestablish anaerobic conditions due to an ability to reduce O2, and resumes normal growth after another few hours. The O2 reducing ability of the organism is due to the presence in the cells of a particle-bound NADH oxidase, a soluble NADPH oxidase and a soluble pyruvate oxidase. The two pyridine nucleotide oxidases reduce O2 to H2O2, the pyruvate oxidase reduces O2 to H2O. Catalase and peroxidase were not detected in anaerobically grown cells. Kinetic studies with cell-free extracts showed that the pyruvate oxidase had a considerably greater affinity (smaller Km) for O2 and capacity (higher Vmax) for O2 reduction than the two other oxidases. It is postulated that the pyruvate oxidase acts as a scavenger for O2, leading to the non-toxic reduction product H2O, and thus functions as a defense mechanism against oxygen toxicity when the organism is exposed to aerobic condition.
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PMID:Oxygen activation and defence against oxygen toxicity in a psychrophilic Bacteroidaceae. 271 28

In order to better understand the enhancing effects of lowered oxygen (O2) tension on the growth in vitro of granulocyte-macrophage progenitor cells (CFU-GM), the effects of oxidizing species derived from molecular O2 were assessed on CFU-GM. Low density or nonadherent low density normal human bone marrow cells were plated at ambient (20%) or lowered (5%) O2 tension in the presence of a source of colony stimulating factors, and in the absence or presence of superoxide dismutase, catalase, glucose oxidase or horseradish peroxidase, alone or in various combinations. Enhanced colony and cluster formation of CFU-GM was noted when low density cells were grown at 5% O2, or when cells were grown at 20% O2 in the presence of superoxide dismutase or glucose oxidase. Both of these enzymes are capable of generating hydrogen peroxide (H2O2), although by different mechanisms. Low concentrations of glucose oxidase resulted in increased formation of colonies and clusters, but higher concentrations of glucose oxidase were inhibitory. Catalase, which converts H2O2 to H2O, had no effect by itself on cells growing at 20% O2, but it eliminated the superoxide dismutase and glucose oxidase enhancing effects. Catalase decreased colony formation of cells grown at 5% O2. Removal of adherent cells ablated the growth-enhancing effects noted at lowered (5%) O2 tension and also the superoxide dismutase and catalase effects at 20% or 5% O2. Horseradish peroxidase, which converts H2O2 to a more toxic oxidant, hypochlorite, had a suppressive effect on colony and cluster numbers and at 20% O2 converted the glucose oxidase effects from stimulatory to inhibitory. The results suggest that adherent cells and low concentrations of H2O2 may mediate growth-enhancing effects of CFU-GM seen at lowered (5%) O2 tension.
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PMID:The effects of oxidizing species derived from molecular oxygen on the proliferation in vitro of human granulocyte-macrophage progenitor cells. 273 50

We measured pulmonary epithelial permeability by quantifying the disappearance of two water-soluble compounds, [14C]mannitol and [3H]inulin, after their instillation, with and without phorbol myristate acetate (PMA), into gas-filled perfused (50 ml/min) rabbit lungs in situ. Both tracers disappeared in a monoexponential fashion over 30 min with calculated first-order rate constants (control; n = 11) of 0.0008 +/- 0.0002 and 0.0027 +/- 0.0008 min-1 for inulin and mannitol, respectively. The ratio of the rate constants (3.1 +/- 0.5) was not significantly different from the ratio of diffusivities of mannitol:inulin (3.7). Addition of PMA (250 micrograms) significantly (n = 9, P less than 0.05) increased the rate constants for both inulin and mannitol to 0.0024 +/- 0.0007 and 0.0087 +/- 0.0025 min-1, respectively, while not affecting their ratio (4.3 +/- 0.5). Addition of human leukocytes (4-8 X 10(8)/l) to the perfusate did not exacerbate the effect of 250 micrograms PMA (n = 3). The addition of catalase (n = 7) completely inhibited the effect of 250 micrograms PMA. PMA (250 micrograms) did not significantly affect perfusion pressure but increased wet-to-dry weight ratios. Light microscopic histology showed damage to epithelial and endothelial cells after 250 micrograms PMA which was not seen after coinstillation of catalase. Catalase sensitivity of functional and structural effects of PMA suggests that the effect was secondary to production of hydrogen peroxide. Since this effect was noted in lungs not perfused with neutrophils and addition of leukocytes did not exacerbate the increase in permeability, we hypothesize that an undetermined pulmonary cell type was the source of hydrogen peroxide. Finally, we found no evidence for restrictive pores with radii of 0.4-1.4 nm.
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PMID:Rapid increases in respiratory epithelial permeability occur after intratracheal instillation of PMA. 311 20

We determined the effect of H2O2 on both the physiological and biochemical lung changes seen in the adult sheep after endotoxin. Fourteen unanesthetized adult sheep with chronic lung lymph fistula were given Escherichia coli endotoxin (1 microgram/kg) over 30 min. Seven sheep were given catalase (32,500 U/kg body wt) as an intravenous bolus 30 min before endotoxin. Four sheep were given catalase alone. Oxidant lung changes were measured using arterial plasma conjugated dienes and lung tissue malondialdehyde (MDA) content, both reflecting the lipid peroxidation process. Animals were killed 5 h after endotoxin. We found that endotoxin alone caused an early increase in pulmonary arterial pressure lung lymph flow (QL), plasma thromboxane B2, 6-keto-prostaglandin F1 alpha, and plasma conjugated dienes. A decrease in cardiac output and arterial PO2 was also seen. A three- to four-fold increase in protein-rich QL was noted at 3-4 h as well as a continued increase in arterial conjugated dienes. Lung MDA and water content were also significantly increased from base line. Catalase pretreatment significantly attenuated both the physiological changes and the prostanoid and conjugated diene release. Lung MDA and water content also remained at base line. We conclude that H2O2 plays a major role in endotoxin-induced lung injury as well as the resulting lipid peroxidation process.
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PMID:Catalase prevents prostanoid release and lung lipid peroxidation after endotoxemia in sheep. 318 91

Catalase in extracts of the extreme halophile Halobacterium cutirubrum exhibits up to threefold stimulation by 0.5 to 1.5 m monovalent salts and by 0.1 m divalent salts. Above these concentrations, inhibition of enzyme activity is observed. The inhibitory effect, and to some extent the stimulation, is salt-specific; the effectiveness of a salt in inhibiting enzyme activity depends on both cation and anion. Thus, the order of effectiveness is MgCl(2) > LiCl > NaCl > KCl > NH(4)Cl, and LiCl > LiNO(3) > Li(2)SO(4). The magnitude of enzyme inhibition for the salts tested is positively correlated with their molar vapor pressure depression in aqueous solution. Stimulation of enzyme activity was observed when one salt was added at its optimal concentration in the presence of inhibiting concentrations of another salt, indicating that the effect on the enzyme is not due to changing water activity but probably to enzyme-salt interaction. Aqueous solutions of ethylene glycol, glycerol, and dimethyl sulfoxide containing no ions influence enzyme activity in the same manner as do salts.
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PMID:Effect of salts and organic solvents on the activity of Halobacterium cutirubrum catalase. 578 14

Polymorphonuclear leukocytes and other inflammatory cells release superoxide anion and additional oxidant species following stimulation. Corneal endothelial cells were exposed to a flux of chemically generated superoxide anion (oxygen-free radical) produced by the combination of 1 mM hypoxanthine and 0.06 U/ml xanthine oxidase. Exposure of endothelial cells to the combination of hypoxanthine and xanthine oxidase resulted in anatomic disruption of the cells with interference in the function of endothelial water movement and resultant swelling of the corneal stroma. Catalase reduced the corneal swelling caused by exposure of endothelium to the oxygen-free radical generating system, whereas superoxide dismutase, ascorbic acid, D-mannitol, and ethanol did not prevent damage. The data suggest that hydrogen peroxide produced during the dismutation reaction of the superoxide anion is one of the toxic species, whereas the superoxide anion itself and the hydroxyl-free radical probably do not participate. The data suggest that corneal endothelial cells are susceptible to physiologic and anatomic damage induced by the products of reactive oxygen species, which, from previous studies, are known to be generated by inflammatory cells. The development of therapeutic modalities directed at the prevention of damage produced by hydrogen peroxide and other oxidant species may be of benefit in reducing corneal endothelial cell damage secondary to ocular inflammatory disease processes.
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PMID:Hydrogen peroxide-mediated corneal endothelial damage. Induction by oxygen free radical. 643 89

The effects of scald injury and scald injury with pretreatment on plasma and water content were studied in the superfused hamster cheek pouch. Catalase (30,000 Units/kg), indomethacin (2.5 mg/kg) and FPL 55712 (2 mg/kg) were administered prior to 10 second scald with 100 degrees C normal saline. Plasma content was measured with 125 I serum albumin and water content was calculated by loss on drying. Significant (P less than 0.05) decreases in plasma content compared to scald alone were observed following pretreatment with catalase (29%) indomethacin (31%) or FPL 55712 (52%). Water content in scalded pouches was significantly reduced by catalase (29%) and FPL 55712 (42%). Pretreatment when combined also resulted in significant reduction of plasma content but not water content. Results suggest that free-radicals, prostaglandins and leukotrienes are involved in vascular response by scald injury.
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PMID:The effects of catalase, indomethacin and FPL 55712 on vascular permeability in the hamster cheek pouch following scald injury. 658 46

Incidences of duodenal tumor induced by oral administration of hydrogen peroxide (HPO) and catalase activities in the duodenal mucosa, blood and liver were correlated in C3H/HeN, C57BL/6N, (C57BL X C3H)F1 (B6C3F1) and hypocatalasemic C3H/Cbs mice. A solution of 0.4% HPO was given to the mice as drinking water for about 6 months. Incidences of duodenal tumor were 11.1% in C3H, 31.8% in B6C3F1, 100% in C57BL and 91.7% in C3H/Cbs mice. Catalase activities (10(-4) k/mg protein) in the duodenal mucosa, blood and liver were 5.3, 7.8 and 75.3 in C3H, 1.7, 7.7 and 62.8 in B6C3F1, 0.7, 5.1 and 40.7 in C57BL, and 0.4, 0.4 and 33.3 in C3H/Cbs mice, respectively. The coefficients of correlation (r) of catalase activities with the incidences of duodenal tumor in C3H, B6C3F1 and C57BL mice are -0.83 in duodenal mucosa, -0.98 in blood and -0.99 in liver. The results indicate that the incidence of duodenal tumor induction by HPO is dependent on the individual mouse strain and may be determined by the genes controlling the catalase activities.
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PMID:Correlation between induction of duodenal tumor by hydrogen peroxide and catalase activity in mice. 672 24

Streptococcus faecalis var. zymogenes was grown aerobically and anaerobically in the presence and absence of haematin, with glycerol as the carbon and energy source. Aerobic growth was stimulated by the inclusion of haematin in the medium but fumarate had no effect on growth. The bacterium was unable to grow anaerobically on glycerol unless fumarate was present; haematin had no effect on growth. NADH oxidase activity, which catalysed the oxidation of NADH + H+ to form H2O rather than H2O2, was found in the soluble fraction and was induced by aerobic growth but partially repressed when haematin was present in the medium. In contrast, a particulate NADH oxidase, which was sensitive to inhibition by antimycin A and 2-heptyl-4-hydroxyquinoline N-oxide, was induced by aerobic growth in the presence of haematin. NADH peroxidase was massively induced by aerobic growth, whereas more lactate dehydrogenase activity was found in anaerobically grown bacteria. Catalase was formed only during aerobic growth in the presence of haematin.
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PMID:Growth of Streptococcus faecalis var. zymogenes on glycerol: the effect of aerobic and anaerobic growth in the presence and absence of haematin on enzyme synthesis. 680 86

The peroxidase-supported N-demethylations catalyzed by chloroperoxidase, a heme protein isolated from Caldariomyces fumago, have been investigated as models for cytochrome P-450-catalyzed N-dealkylations. The turnover number for the ethyl hydrogen peroxide-supported dealkylation of N,N-dimethylaniline by chloroperoxidase (1476) was much greater than that for cytochrome P-450-catalyzed dealkylations. The dealkylations of N,N-dimethylaniline by chloroperoxidase yielded N-methylaniline and formaldehyde in equimolar amounts with no other products detectable by high pressure liquid chromatography analysis of the reaction mixture. Ethyl hydrogen peroxidase could be replaced by other hydroperoxides, peroxides, or peracids. Chloride ions stimulated the reaction at low pH. The dealkylation reaction exhibited normal Michaelis-Menten saturation kinetics with respect to N,N-dimethylaniline (Km = 0.08 mM) and ethyl hydrogen peroxide (Km = 0.8 mM) at low substrate concentrations. However, substrate inhibition occurred at higher concentrations of N,N-dimethylaniline. The chloroperoxidase-catalyzed demethylations were inhibited by inhibitors of cytochrome P-450 such as azide or n-propyl gallate, but not by metyrapone, SKF-525A, or piperonyl butoxide. Although tiron and DL-epinephrine, trapping agents for the superoxide anion, inhibited the demethylation reactions, superoxide dismutase had no effect. There was no significant inhibition by alpha-phenyl-t-butyl-nitrone or 5,5-dimethyl-pyrroline-N-oxide, which react with free radicals. Diphenylfuran and DL-histidine, which react with singlet oxygen, did not inhibit the reaction. Substitution of D2O for H2O resulted in a marked inhibition with a solvent isotope effect (VH/VD) of 3.6. Chloroperoxidase did not catalyze the demethylation of N,N-dimethylaniline-N-oxide, indicating that the reaction does not proceed via an N-oxide intermediate.
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PMID:N-Demethylation reactions catalyzed by chloroperoxidase. 719 53


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