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)

Homogenates of HTC cells have been fractionated by differential centrifugation (in four particulate fractions: N, M, L, P, and a supernatant S) or isopycnic banding in linear sucrose gradients. On this basis, the following subcellular organelles may be characterized: (i) Mitochondria, detected by cytochrome oxidase and succinodehydrogenase, are collected in the M and L fractions, and equilibrate, as a narrow band, at a median buoyant density of 1.18 g/cm3. (ii) Lysosomes, detected by the latent hydrolases beta-glycerophosphatase and N-acetyl-beta-glucosaminidase, are largely sedimented in the M and L fractions, and display a broad density distribution pattern with a median value of 1.17 g/cm3. This density is decreased or increased after cultivation of the cells in presence of Triton WR-1339 or Dextran 500, respectively. The behavior of cathepsin D is somewhat at variance with that of the two other hydrolases. (iii) Plasma membrane is tentatively detected by alkaline phosphodiesterase I. Largely recovered in the P fraction, this enzyme equilibrates at a median density close to that of the lysosomal hydrolases; the bulk of cholesterol and about half of the leucyl-2-naphthylamidase are closely associated with alkaline phosphodiesterase I; HTC cells do not contain typical 5'-nucleotidase. (iv) Catalase-bearing particles, of high buoyant density (1.22 g/cm3) are present, but 30-40% of the catalase is also found readily soluble. NADPH- and NADH: cytochrome c reductase, and RNA show more complex distributions. It is suggested that the former enzyme is associated with the endoplasmic reticulum; as in liver, NADH reductase activity is shared between the endoplasmic reticulum and the mitochondria; half of the RNA is associated with free ribosomes of polysomes. True glucose-6-phosphatase could not be detected.
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PMID:Analytical fractionation of cultured hepatoma cells (HTC cells). 56 43

Histochemical and cytochemical studies were done to further characterize the preneoplastic hepatocytes with extraperoxisomal catalase (EPC-cells) that were found in the livers of rats fed 3'-methyl-4-dimethylaminoazobenzene. Catalase activity was demonstrated cytochemically to be localized in nuclear matrices, hyaloplasm, and peroxisomal matrices of EPC-cells. It is suggested that an impairment of peroxisome formation is involved in the altered intracellular distribution of catalase. Administration of clofibrate increased the catalase activity in EPC-cells. To examine the preneoplastic nature of EPC-cells, activities of glucose-6-phosphatase (G6Pase) and gamma-glutamyl transpeptidase (GGT) were examined, since changes in the activities of these enzymes have been used as markers of putative preneoplastic cells. In the present study, neither weak G6Pase activity nor positive GGT activity was considered to be a consistent feature of EPC-cells. However, available evidence suggests that EPC-cells are one of the carcinogen-induced cell populations with altered phenotypes.
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PMID:Hepatocytes with extraperoxisomal catalase in rats fed 3'-methyl-4-dimethylaminoazobenzene. 711 45