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)

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.
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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

Catalase-peroxidase was purified to near homogeneity from Streptomyces sp. The enzyme was composed of two subunits with a molecular mass of 78 kDa and contained 1.05 mol of protoporphyrin IX/mol of dimeric protein. The absorption and resonance Raman spectra of the native and its cyano-enzyme were closely similar to those of other heme proteins with a histidine as the fifth ligand. However, the peak from tyrosine ring at approximately 1612 cm-1, which is unique in catalases, was not found in resonance Raman spectra of catalase-peroxidase. The electron paramagnetic resonance spectrum of the native enzyme revealed uniquely two sets of rhombic signals, which were converted to a single high spin, hexacoordinate species after the addition of sodium formate. Cyanide bound to the sixth coordination position of the heme iron, thereby converting the enzyme to a low spin, hexacoordinate species. The time-dependent inactivation of the enzyme with diethyl pyrocarbonate and its kinetic analysis strongly suggested the occurrence of histidine residue. From the above-mentioned spectroscopic results and chemical modification, it was deduced that the native enzyme is predominantly in the high spin, ferric form and has a histidine as the fifth ligand.
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PMID:Spectral characterization and chemical modification of catalase-peroxidase from Streptomyces sp. 777 29