Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hydralazine caused site-specific DNA damage in the presence of Cu(II), Co(II), Fe(III), or peroxidase/H2O2. The order of inducing effect of metal ions on hydralazine-dependent DNA damage [Cu(II) greater than Co(II) greater than Fe(III)] was related to that of accelerating effect on the O2 consumption rate of hydralazine autoxidation. Catalase completely inhibited DNA damage by hydralazine plus Cu(II), but hydroxyl radical (.OH) scavengers and superoxide dismutase did not. On the other hand, DNA damage by hydralazine plus Fe(III) was inhibited by catalase and .OH scavengers. Hydralazine plus Cu(II) induced piperidine-labile sites predominantly at guanine and some adenine residues, whereas hydralazine plus Fe(III) caused cleavages at every nucleotide. Activation of hydralazine by peroxidase/H2O2 caused guanine-specific modification in DNA. ESR-spin trapping experiment showed that .OH and superoxide are generated during the Fe(III)- or Cu(II)-catalysed autoxidation of hydralazine, respectively, and that nitrogen-centered radical is generated during the Cu(II)- or peroxidase-catalysed oxidation. The generation of nitrogen-centered radical was also supported by HPLC-mass spectrometry. The results suggest that the guanine-specific modification by the enzymatic activation of hydralazine is due to the nitrogen-centered hydralazyl radical or derived active species, whereas .OH participates in DNA damage by hydralazine plus Fe(III). The mechanism of hydralazine plus Cu(II)-induced DNA damage is complex. The possible role of the DNA damage induced by hydralazine in the presence of Cu(II) or peroxidase/H2O2 is discussed in relation to hydralazine-induced lupus, mutation, and cancer.
 ...
PMID:Free radical production and site-specific DNA damage induced by hydralazine in the presence of metal ions or peroxidase/hydrogen peroxide. 184 78

Cell-free supernatant from formylmethionyl-leucyl-phenylalanine (fMLP)-activated granulocytes causes a time- and concentration-dependent stimulation of prostaglandin E2 (PGE2) production in amnion cells. PGE2 concentration in the culture medium after 36 h treatment with granulocyte supernatant (from 40 x 10(6) granulocytes/ml of amnion cell medium), 1.49 +/- 0.71 pg/ng DNA (n = 13), was significantly higher (p = 0.0015) than in control cells (0.33 +/- 0.23 pg/ng DNA, n = 13). Indomethacin abolished this stimulation. Granulocyte supernatant and human epidermal growth factor (hEGF) had an additive effect on amnion cell PGE2 production. Catalase, superoxide dismutase (SOD), protease inhibitors or the platelet-activating factor (PAF) antagonist L-659,989 had no effect. Actinomycin D, cycloheximide and mepacrine reduced the PGE2 production. The phospholipase A2 activity present in granulocyte supernatants was resistant to heating, whereas heating decreased their PGE2-stimulating activity by 92%. Exogenous phospholipase A2 had no effect on PGE2 synthesis. The granulocyte product could be precipitated with ammonium sulphate. On gel filtration of supernatant, two peaks of PGE2-synthesis stimulating activity were obtained (molecular weights 12,000 and 60,000). This data serve to explain the association of chorioamnionitis with preterm labor: activated granulocytes release a protein(s) that induces prostaglandin production in amnion cells, and thus promote labor.
 ...
PMID:A product of activated human granulocytes stimulates prostaglandin E2 synthesis in human amnion cells. 188 40

Campylobacter species were isolated from 93 (15%) of 631 Thai children with diarrhea using the membrane filter technique on nonselective blood agar incubated at 37 degrees C. Campylobacter jejuni was isolated from 62 (10%), Campylobacter coli from 14 (2%), and atypical campylobacters from 17 (3%). The 17 atypical strains were first characterized biochemically and by dot blot DNA hybridization. Catalase-negative strains also were characterized by DNA hybridization and ribotype pattern. One strain was a catalase-negative "Campylobacter upsaliensis" and another was a nitrate-negative Campylobacter jejuni doylei. Fifteen isolates were aerotolerant strains most closely resembling Campylobacter cryaerophila or "C. upsaliensis" by dot hybridization. These aerotolerant strains, designated group 2 ("Campylobacter butzleri"), had ribotypes distinct from C. cryaerophila and have previously been shown to be related by DNA hybridization at the species level to the group 2 aerotolerant Campylobacter type strain (D2686). Group 2 aerotolerant Campylobacter were the atypical Campylobacter species most frequently isolated from Thai children with diarrhea.
 ...
PMID:Isolation of group 2 aerotolerant Campylobacter species from Thai children with diarrhea. 201 54

Previously, we identified p-benzoquinone (BQ) and 1,2,4-benzenetriol (BT) as toxic metabolites of benzene on the basis of their inhibitory effect on DNA synthesis. In the present study, the capability of benzene and the two metabolites to induce DNA strand breaks was investigated in either the in vivo or the in vitro system by comparing the DNA elution rate on a fine membrane filter at alkaline pH. In the in vitro system were bone marrow cells were reacted with test chemicals for 60 min, both BQ and BT induced a dose-related increase in alkali-labile DNA single-strand breaks (SSBs) of bone marrow cells. However, when glutathione (350 micrograms/ml) was added to the same reaction system, the DNA damaging effect of BQ (24 microM) and BT (24 microM) was blocked by 100 and 53%, respectively. Catalase (130 units/ml) completely blocked the DNA damaging effect of BT, while no protection was afforded with BQ. Consistent with these observations, no induction of alkali-labile DNA SSBs was observed in the in vivo system by an anesthetic dose of benzene (1760 mg/kg, ip or po) at 1, 24, and 36 hr postadministration in both male and female ICR mice. These results suggest that benzene exposure would not induce direct DNA strand breaks in vivo under realistic work-related or accidental exposure conditions and also indicate that caution should be exercised in the interpretation of in vitro data for whole-body toxicity evaluation.
 ...
PMID:Effects of benzene on DNA strand breaks in vivo versus benzene metabolite-induced DNA strand breaks in vitro in mouse bone marrow cells. 202 Sep 71

Transcription of the Saccharomyces cerevisiae CTT1 gene encoding the cytosolic catalase T has been previously shown to be derepressed by nutrient stress. To investigate whether expression of this gene is also affected by other types of stress, the influence of heat shock on CTT1 expression was studied. The results obtained show that expression of the gene is low at 23 degrees C and is induced rapidly at 37 degrees C. By deletion analysis, a promoter element necessary for high level induction by heat shock was located between base pairs -340 and -364 upstream of the translation start codon. This region was demonstrated to be sufficient for heat shock control by placing it upstream of a S. cerevisiae LEU2-lacZ fusion gene. Mutagenesis of the region showed that the response to heat shock is not mediated by a sequence similar to canonical heat shock elements, but by DNA elements also involved in nutrient control of transcription. Catalase T appears to have a function in protecting yeast cells against oxidative damage under stress conditions. Catalase T-containing strains are less sensitive to exposure to 50 degrees C ("lethal heat shock") than isogenic catalase T-deficient mutants, and catalase T-containing strains pretreated by incubation at 37 degrees C are less sensitive to H2O2 than pretreated catalase-deficient mutants.
 ...
PMID:Heat shock factor-independent heat control of transcription of the CTT1 gene encoding the cytosolic catalase T of Saccharomyces cerevisiae. 206 15

Treatment of quiescent Balb/3T3 clone A31-1-1 cells with 0.1-0.2 mM H2O2 in the presence of 1 microM insulin induced DNA synthesis 20-24 h later at almost the same level as that in cells treated with 10% serum. Treatment with 0.1-0.2 mM H2O2 alone did not induce DNA synthesis and was not toxic to the cells. Cell cycle analysis indicated that treatment with H2O2 plus insulin induced progression of the cell cycle from the quiescent state. The amounts of mRNA for competence family genes such as c-fos, KC and JE were increased by the addition of H2O2. Under these conditions H2O2 caused rapid phosphorylation of a protein of 78 kDa with a pI of 6.3 (p78). Phosphorylation of p78 increased on treatment with TPA and serum as well. Catalase reduced the increase in phosphorylation of p78 induced by TPA and serum. Endogenous production of H2O2 was observed within 10 min after treatment of quiescent cells with platelet derived growth factor (PDGF) or 12-O-tetradecanoylphorbol-13-acetate (TPA). These results indicate that H2O2 at certain concentrations mimics the action of competence factors on resting Balb/3T3 cells.
 ...
PMID:Stimulation by hydrogen peroxide of DNA synthesis, competence family gene expression and phosphorylation of a specific protein in quiescent Balb/3T3 cells. 211 40

Damage to the bases in DNA by the cupric ion-1,10-phenanthroline complex was investigated. Ten base products in DNA were identified and quantitated by the use of gas chromatography/mass spectrometry with selected-ion monitoring. DNA damage by the cupric ion-1,10-phenanthroline complex required the presence of a reducing agent such as ascorbic acid or mercaptoethanol. Products identified were typical hydroxyl radical induced products from the pyrimidines and purines in DNA, well-known from previous studies using various hydroxyl radical producing systems such as ionizing radiation, hypoxanthine/xanthine oxidase, or hydrogen peroxide in the presence of transition metal ions. Product formation was not significantly inhibited by typical scavengers of hydroxyl radical such as mannitol and sodium formate, but there was partial inhibition by dimethyl sulfoxide. Catalase substantially decreased formation of base products, and added hydrogen peroxide stimulated it, indicating the hydrogen peroxide dependency of DNA base damage. Superoxide dismutase afforded only a partial reduction in product yields in systems containing ascorbic acid. On the basis of the types of base products formed, the hydrogen peroxide dependency of product formation, and a previous report suggesting that DNA damage is due to a diffusible species [Williams, L. D., Thivierge, J., & Goldberg, I. H. (1988) Nucleic Acids Res. 16, 11607-11615], we propose that DNA base damage is caused by hydroxyl radical.
 ...
PMID:Modification of bases in DNA by copper ion-1,10-phenanthroline complexes. 212 17

Reactivities of o-phenylphenol and its metabolites (2,5-dihydroxybiphenyl, 2-phenyl-1,4-benzoquinone) with DNA were investigated by a DNA sequencing technique, and the reaction mechanism was studied by UV-visible and ESR spectroscopies. In the presence of Cu(II), 2,5-dihydroxybiphenyl caused strong DNA damage even without piperidine treatment. Catalase, methionine, and methional inhibited the DNA damage completely, whereas mannitol, sodium formate, ethanol, tert-butyl alcohol, and superoxide dismutase did not. 2,5-Dihydroxybiphenyl plus Cu(II) frequently induced a piperidine-labile site at thymine and guanine residues. The addition of Fe(III), Mn(II), Co(II), Ni(II), Zn(II), Cd(II), or Pb(II) did not induce DNA damage with 2,5-dihydroxybiphenyl. When H2O2 was added, 2-phenyl-1,4-benzoquinone also induced DNA damage in the presence of Cu(II). Cu(II) accelerated the autoxidation of 2,5-dihydroxybiphenyl to quinone. An ESR study revealed that the semiquinone radical is an intermediate of the autoxidation. Catalase had no inhibitory effect on the acceleration by Cu(II). Superoxide dismutase promoted both the autoxidation of 2,5-dihydroxybiphenyl and the initial rate of semiquinone radical production. ESR spin trapping experiments showed that the addition of Fe(III) produced hydroxyl radical during the autoxidation of 2,5-dihydroxybiphenyl, whereas the addition of Cu(II) hardly did so. The results suggest that DNA damage by 2,5-dihydroxybiphenyl plus Cu(II) is due to active species other than hydroxyl free radical.
 ...
PMID:DNA damage induced by metabolites of o-phenylphenol in the presence of copper(II) ion. 213 Sep 42

Induction of recA in Escherichia coli, monitored as beta-D-galactosidase (beta-Gal) activity in recA-lacZ fusion strains, was shown to be elevated and prolonged by dithiothreitol (DTT) treatment after far-UV radiation. Pretreatment of UV-irradiated cultures using DTT led to a shortened recA response and little increase of beta-Gal yield. Similar studies were performed using a catalase-deficient recA-lacZ strain in which the major feature was elevated levels of recA-lacZ induction. Catalase activity in UV-irradiated wild-type cells was reduced by DTT treatment to levels as low as in a katE mutant strain, leading to similar recA-lacZ induction patterns between the strains. Neither DTT nor H2O2 treatment of cells could induce significant recA transcription in the absence of UV-radiation, implying that both agents modify recA activity primarily by interfering with repair of recA-inducing DNA lesions. The results confirm previous studies suggesting that modification of DNA repair is probably a significant portion of thiol radiation protection.
 ...
PMID:Thiol and hydrogen peroxide modification of recA induction in UV-irradiated wild-type and catalase-deficient Escherichia coli K12. 215 83

We have isolated, following one-step mutagenesis, a Chinese hamster ovary cell mutant hypersensitive to the intercalating agent, adriamycin (4-fold compared to parental CHO-K1 cells). This agent exerts at least part of its cytotoxic action via inhibition of the nuclear enzyme, topoisomerase II. The mutant, designated ADR-3, showed hypersensitivity to all classes of topoisomerase II inhibitors, including actinomycin D, amsacrine (m-AMSA), etoposide (VP16) and mitoxantrone. ADR-3 cells also showed cross-sensitivity to ionizing radiation, but not to UV light. Cellular accumulation of radiolabeled actinomycin D was similar in parental and mutant cells. At equimolar doses, adriamycin induced more protein-associated DNA single- and double-strand breaks in ADR-3 cells than in CHO-K1 cells. Topoisomerase II activity was elevated to a small but significant degree in ADR-3 cells, and this was reflected in a 1.5-fold higher level of topoisomerase II protein in ADR-3 than in CHO-K1 cells, as judged by Western blotting. ADR-3 cells were hypersensitive to cumene hydroperoxide but cross-resistant to hydrogen peroxide, suggesting possible abnormality in the detoxification of peroxides by glutathione peroxidase or catalase. Glutathione peroxidase activity against hydrogen peroxide was similar in CHO-K1 and ADR-3 cell extracts, but activity against cumene hydroperoxide was evaluated to a small but significant extent in mutant cells. Catalase levels were not significantly different in ADR-3 and CHO-K1 cells. ADR-3 cells were recessive in hybrids with parental CHO-K1 cells with respect to sensitivity to topoisomerase II inhibitors and X-rays, and represent a different genetic complementation group from the previously reported adriamycin-sensitive mutant, ADR-1 [Davies et al., J. Biol. Chem., 263 (1988) 17724-17729].
 ...
PMID:Isolation and partial characterisation of a mammalian cell mutant hypersensitive to topoisomerase II inhibitors and X-rays. 215 84


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>