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)

Irradiation of DNA in a nitrogen atmosphere with 60Co gamma-radiation produces at least two types of damage. The first type leads to single strand breaks in the DNA observed after exposure to alkali. This type of alkali-labile bond will be designated a spontaneous break. The second type of damage to DNA is an alteration which makes the DNA susceptible to phosphodiester bond hydrolysis by a 1600-fold purified preparation of endonuclease II of Escherichia coli and is designated an enzyme-sensitive site. This site is not alkali-labile. After irradiation, preincubation of the DNA either for days at 0 degrees or for 4 hr at 37 degrees increases both the spontaneous breaks and the enzyme sensitive sites. There is a greater increase of spontaneous breaks when the preincubation is in O2 compared to N2. The increase of enzyme sensitive sites due to the preincubation is not altered significantly by O2. The increase of spontaneous breaks during the preincubation is almost completely prevented by addition of either NaBH4 or NH2OH after the irradiation. The treatment can be before or after the preincubation. This effect indicates that these breaks are due to alkali-labile bonds possibly produced by depurination or depyrimidination reactions. That the spontaneous breaks are due primarily to alkali-labile bonds is supported by an experiment in which formamide gradients were used. Neither NaBH4 nor NH2OH has any effect on the enzyme sensitive sites. Addition of beta-mercaptoethanol (0.5 M) at the start of the preincubation prevents in part the appearance of both spontaneous breaks and enzyme-sensitive sites. It has no effect when added at the end of the preincubation. Catalase added before the preincubation has no effect on either type of damage. It is postulated that the spontaneous breaks occur because purine or pyrimidine radicals are formed (possibly hydroxyl radicals) which can then interact with oxygen to produce unstable intermediates. The intermediates then undergo either depurination or depyrimidination. The subsequent alkali catalyzed beta-elimination reaction of depurinated or depyriminidinated DNA is prevented by NaBH4 or NH2OH. An alternative hypothesis would involve damage to the sugar rather than to bases. The enzyme-sensitive sites represent another form of base damage which is not oxygen dependent. The chemical nature of either form of primary damage is not known.
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PMID:Endonuclease II of Escherichia coli: degradation of gammairradiated DNA. 109 Dec 87

Release of iron from ferritin by the polyhydroxypyrimidines, dialuric acid, isouramil, divicine, and acid-hydrolyzed vicine, was measured. Iron was released at fast initial rates which gradually declined to zero in 10 min. All the compounds were better reductants for ferritin-iron under nitrogen than in air. The effects of superoxide dismutase, catalase, and glutathione on both initial rates and total iron released over 30 min in air were determined. Major effects were inhibition by superoxide dismutase for divicine and isouramil and enhancement for dialuric acid and acid-hydrolyzed vicine. Glutathione promoted increased iron release that was further enhanced by superoxide dismutase. These increases were particularly striking over the longer time period. Catalase, in all cases, gave modest enhancement. Enhanced iron release correlated with inhibition of pyrimidine oxidation. The results indicate that the reduced form of each pyrimidine releases ferritin iron directly, and the effects of the antioxidants are mainly to maintain or regenerate the reduced pyrimidines. A combination of each pyrimidine and ferritin caused peroxidation of phopholipid liposomes, above that seen with the pyrimidines and adventitious iron. Glutathione, superoxide dismutase, and catalase modulated lipid peroxidation in a way consistent with their effects being mainly on ferritin-iron release. On the basis of our findings, we propose that the release and subsequent reactions of ferritin-iron may contribute to the toxicity of these compounds. Although glutathione and superoxide dismutase together efficiently inhibit redox cycling and H2O2 production from the pyrimidines, this combination maximized iron release from ferritin and ferritin-dependent lipid peroxidation.
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PMID:Release of iron from ferritin by divicine, isouramil, acid-hydrolyzed vicine, and dialuric acid and initiation of lipid peroxidation. 273 3

Pyrimidine base-derived radical spin adducts were detected in reaction mixtures containing pyrimidine bases, glutathione, and alloxan by the ESR spin trapping technique with a spin trap, alpha-phenyl-N-tert-butyl nitrone (PBN). Pyrimidine nucleoside- and nucleotide-, and ribose- and deoxyribose-derived radical spin adducts of PBN were also observed. However, purine base- and nucleoside-derived radical spin adducts of PBN were not detected. A cytosine-derived radical spin adduct of PBN was not generated under anaerobic conditions. Catalase and mannitol inhibited the formation of the cytosine-derived radical spin adduct of PBN but superoxide dismutase (SOD) did not. EDTA stimulated it and desferrioxamine suppressed it nearly completely. From these results it is presumed that the hydroxyl radical is involved in the formation of the cytosine-derived radical spin adduct of PBN generated by alloxan.
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PMID:Detection of nucleic acid-derived radicals formed by alloxan. 285 9

Polymorphonuclear neutrophils (PMN) are thought to play a role in reperfusion injury and ischemia. These effects are partly mediated by toxic oxygen species (superoxide anion, hydrogen peroxide and hydroxyl radical) acting at the level of the endothelium. It was demonstrated recently that the superoxide anion reacts with nitric oxide (NO) and that interaction leads to the generation of highly toxic peroxynitrite. Several drugs were tested so far in order to affect PMN function. It was demonstrated that dipyridamole (2,6-bis-diethanolamino-4,8-dipiperidinopyrimido-(5,4-d)-pyrimidine) can influence neutrophil function by inhibiting adenosine uptake. However, this action can not fully explain all of the observed effects of dipyridamole action on PMN metabolism. The aim of our study was to evaluate the influence of dipyridamole on nitric oxide production by activated polymorphonuclear neutrophils. Incubation of PMNs with hydroxylamine (HA) and phorbol myristate acetate (PMA) generated nitrite (36.4+/-4.2 nmol/h 2x10(6) PMN), dipyridamole at 100 micromol/l, 50 micromol/l and 10 micromol/l caused a considerable drop in nitrite production (11.8+/-1.8, 19.7+/-2.7 and 27.4+/-3.2 nmol/h, respectively). Neither adenosine nor the adenosine analogue could mimic the dipyridamole effect. Moreover theophylline, an adenosine inhibitor could not reverse the dipirydamole action on PMN metabolism. We also found that dipyridamole inhibited hydrogen peroxide release from neutrophils. Catalase that scavenges hydrogen peroxide also largely abolished nitric oxide release from PMN. It is evident that dipyridamole inhibits hydroxylamine-augmented nitric oxide production by activated polymorphonuclear neutrophils through an adenosine-independent mechanism.
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PMID:Dipyridamole inhibits hydroxylamine augmented nitric oxide (NO) production by activated polymorphonuclear neutrophils through an adenosine-independent mechanism. 1558 33

Fluoranthene is a polycyclic aromatic hydrocarbon (PAH) commonly present in PAH-contaminated soils. We studied fluoranthene catabolism and associated proteins in Mycobacterium sp. JS14, a bacterium isolated from a PAH-contaminated soil in Hilo (HI, USA). Fluoranthene degrades in at least three separated pathways via 1-indanone, 2',3'-dihydroxybiphenyl-2,3,-dicarboxylic acid, and naphthalene-1,8-dicarboxylic acid. Part of the diverse catabolism is converged into phthalate catabolism. An increased expression of 25 proteins related to fluoranthene catabolism is found with 1-D PAGE or 2-DE and nano-LC-MS/MS. Detection of fluoranthene catabolism associated proteins coincides well with its multiple degradation pathways that are mapped via metabolites identified. Among the up-regulated proteins, PAH ring-hydroxylating dioxygenase alpha-subunit and beta-subunit and 2,3-dihydroxybiphenyl 1,2-dioxygenase are notably induced. The up-regulation of trans-2-carboxybenzalpyruvate hydratase suggests that some of fluoranthene metabolites may be further degraded through aromatic dicarboxylic acid pathways. Catalase and superoxide dismutase were up-regulated to control unexpected oxidative stress during the fluoranthene catabolism. The up-regulation of chorismate synthase and nicotine-nucleotide phosphorylase may be necessary for sustaining shikimate pathway and pyrimidine biosynthesis, respectively. A fluoranthene degradation pathway for Mycobacterium sp. JS14 was proposed and confirmed by proteomic study by identifying almost all the enzymes required during the initial steps of fluoranthene degradation.
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PMID:Fluoranthene metabolism and associated proteins in Mycobacterium sp. JS14. 1751 77