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)

Enzyme cytochemistry has been used, at the light and electron microscope levels, to "mark" cytoplasmic organelles of mammalian cells. Catalase cytochemistry permitted identification of microperoxisomes, apparently ubiquitous organelles that are attached by numerous slender connections to the endoplasmic reticulum. Thiamine pyrophosphatase and acid phosphatase cytochemistry can be used to distinguish between the Golgi apparatus and a specialized acid-phosphatase-rich region of smooth endoplasmic reticulum (ER) that appears to be involved in: (a) the formation of lysosomes and melanin granules: (b) the processing and packaging of secretory materials in endocrine and exocrine cells; and (c) the metabolism of lipid. The acronym GERL has been given to this region of smooth ER because it is located at the inner or "trans" aspect of the Golgi apparatus and because it appears to produce various types of Lysosomes.
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PMID:The endoplasmic reticulum: a cytochemist's view (a review). 18 10

The aims of this study were to differentially identify peroxisomes and lysosomes in Leydig cells of the sexually mature rat using cytochemical techniques, to describe the size and shape of peroxisomal profiles, and to localize catalase and sterol carrier protein-2 (SCP2) in Leydig cell peroxisomes. Peroxisome profiles, identified by cytochemical staining for catalase activity using 3,3'-diaminobenzidine tetrahydrochloride (DAB) were categorized according to their longest diameter as small (less than 0.18 microns), intermediate (0.18-0.45 microns), and large (more than 0.45 microns); and according to their shape, which were designated as circular, oval, and dumbbell. Together these peroxisomal profiles occupied 11.2 microns 3/Leydig cell. Lysosomes, identified in the same tissue sections as acid phosphatase positive organelles, occupied 12.9 microns 3/Leydig cell. Negative bodies with morphology identical to cytochemically unstained peroxisomes also were detected. These organelles occupied 14.5 microns 3/Leydig cell. Catalase was immunolocalized exclusively in Leydig cell peroxisomes using AuroProbe EM protein A G10 (ie, 10 nm gold particles). Sterol carrier protein-2 was immunolocalized in Leydig cell peroxisomes by AuroProbe EM protein A G15 (ie, 15 nm gold particles). Immunolocalization of catalase and SCP2 using 10 nm and 15 nm gold particles in the same peroxisomes confirmed that Leydig cell peroxisomes contain SCP2. Taken together, these results show conclusively that adult rat Leydig cell peroxisomal profiles occur in different shapes and sizes, which suggests the existence of a network of peroxisomes, rather than peroxisomes occurring as separate isolated organelles. More importantly, the present study demonstrates for the first time that Leydig cell peroxisomes contain SCP2.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Studies on peroxisomes of the adult rat Leydig cell. 238 46

The cytoplasmic organelles of different protozoa of the family Trypanosomatidae were characterized by ultrastructural cytochemistry and stereology. Data were obtained for mitochondria, lipid inclusions, glycosomes (peroxisome-like organelle), empty membrane-bounded vacuoles, reservosomes of Trypanosoma spp., multivesicular body of Crithidia fasciculata and dense granules of Crithidia oncopelti. The stereological analysis (D = mean diameter, Vv = volume density and Nv = numerical density) was performed in glutaraldehyde-formaldehyde and osmium tetroxide-potassium ferricyanide fixed parasites, which showed an excellent preservation of the membranes and cytoplasmic organelles. Lipid inclusions, not limited by a unit membrane, appeared electron-dense after post-fixation in an osmium-imidazole buffered solution. Catalase, a peroxisomal enzyme, was detected only in the glycosomes of the lower trypanosomatids. Empty membrane-bounded vacuoles showed positive reaction when the cells were incubated in a medium specific for the detection of the lysosomal enzyme acid phosphatase. The reservosomes of Trypanosoma spp., sub-genus Schizotrypanum, could be differentiated from the multivesicular bodies of other trypanosomatids, since they lack true vesicles. They contain lipid inclusions dispersed in an electron-dense matrix which stained positively when the cells were incubated in ethanolic phosphotungstic acid to detect basic proteins.
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PMID:Cytoplasmic organelles of trypanosomatids: a cytochemical and stereological study. 313 13

Homogenates of cultured rat embryo fibroblasts have been assayed for acid phosphatase, N-acetyl-beta-glucosaminidase, cathepsin D, acid deoxyribonuclease, cytochrome oxidase, NADH cytochrome c reductase, 5'-nucleotidase, inosine diphosphatase, acid pyrophosphatase, neutral pyrophosphatase, esterase, catalase, cholesterol, and RNA. The validity of the assay conditions was checked. Neutral pyrophosphatase is a readily soluble enzyme. Acid hydrolases, except acid pyrophosphatase, are particle-bound enzymes, which exhibit a high degree of structural latency. They are activated and solubilized in a parallel fashion by mechanical treatments and tensio-active agents. Catalase is also particle-bound and latent; activating conditions stronger than those for hydrolases are required to activate the enzyme. Acid pyrophosphatase, 5'-nucleotidase and inosine diphosphatase are firmly particle-bound, but not latent; they are not easily solubilized. In differential and isopycnic centrifugation, the latent hydrolases, cytochrome oxidase and catalase dissociate largely from each other; this suggests the occurrence of lysosomes and peroxisome-like structures besides mitochondria. The distribution patterns of 5'-nucleotidase and cholesterol are largely similar; digitonin influences their equilibrium density to the same extent; these two constituents are thought to be related to the plasma membrane. Inosine diphosphatase and acid pyrophosphatase are also partially associated with the plasma membrane, although some part of these enzymic activities probably belongs to other structures. NADH cytochrome c reductase is associated partly with the endoplasmic reticulum, partly with mitochondria.
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PMID:Analytical fractionation of homogenates from cultured rat embryo fibroblasts. 437 90

1. Homogenates of guinea-pig polymorphonuclear leucocytes were separated by differential centrifugation into six particulate fractions and a soluble fraction. 2. The distributions in these fractions of protein, DNA, succinate dehydrogenase, beta-glucuronidase, peroxidase, alkaline phosphatase, acid phosphatase (against p-nitrophenyl phosphate and beta-glycerophosphate), cathepsin, and catalase were compared. 3. Almost all of the DNA sedimented in the first two pellets, indicating that the nuclei were relatively intact. 4. The four hydrolases and peroxidase showed different distribution patterns, although these activities were previously reported to be localized mainly in the single ;granule' fraction isolated from leucocytes. 5. The particles containing peroxidase, acid phosphatase and alkaline phosphatase all exhibited latency. Maximum activity for each enzyme was obtained at roughly similar concentrations of Triton X-100. 6. The acid phosphatase of these cells was distributed between two populations of particles that differed in both sedimentation characteristics and density. The acid phosphatase(s) of the two populations showed slightly different substrate specificities. This bimodal distribution was not an artifact of the procedure used to elicit the cells. 7. Catalase was recovered almost entirely in the soluble fraction and showed no latency in freshly prepared homogenates. No urate oxidase was detected. 8. We conclude that the ;granule' fraction of the polymorphonuclear leucocyte, as isolated by previous workers, contains at least three, probably more, populations of particles with different enzyme contents, and that these cells probably do not contain peroxisomes.
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PMID:The distributions of some granule-associated enzymes in guinea-pig polymorphonuclear leucocytes. 541 96

Neutrophils, isolated in large quantities from porcine blood were disrupted by nitrogen cavitation and separated by differential centrifugation into a nuclear fraction and a post-nuclear supernatant. The latter was subfractionated by sucrose density gradient centrifugation into cytosol, a fraction consisting of membrane vesicles and two granule-rich fractions. The membrane fraction accounted for 1.9% of the protein in the post-nuclear supernatant, the light granule fraction for 2.2% and the dense granule fraction for 4.2%. Catalase, lactate dehydrogenase and malate dehydrogenase were largely confined to the cytosol. The dense granule fraction contained the highest quantities of the hydrolytic enzymes, although the membrane fraction was also rich in alkaline and acid phosphatase and gamma-glutamyl transpeptidase activities. Electron microscopy of the membrane fraction showed intact membrane vesicles, whereas the granular fractions consisted of electron-dense, membrane-bound granules. Two granular fractions were isolated which contained granules of differing size and density. 3H-labeled wheat germ agglutinin bound to the surface of intact neutrophils and when these were disrupted and fractionated the membrane fraction showed a specific binding activity 16-times greater than that of the cavitated sample. The membrane fraction interacted with the detergent digitonin and as a result underwent density perturbation increasing from 1.13 g X cm-3 to 1.18 g X cm-3. Dodecylsulphate-polyacrylamide gel electrophoresis showed the membrane fraction to consist of at least 40 protein bands, with relative molecular masses ranging from 200 000-16 000. The granule fractions contained less protein bands, with a protein composition quite distinct from that of the membrane fraction.
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PMID:Subcellular fractionation of porcine neutrophils by nitrogen cavitation and sucrose-density-gradient centrifugation. 662 89

We compared the antimicrobial function of alveolar macrophages (AM) from adult and 3- to 5-wk-old infant primates (Macaca nemestrina) and the effects of the immunomodulator, aminobutyryl muramyl dipeptide (abu-MDP) on this function. Phagocytosis of Staphylococcus aureus (SA) and group B streptococcus (GBS) by adult and infant AM was comparable. Adult and infant AM killed SA equally within 15 min of incubation; however, after 45 min, with phagocytosis of additional bacteria, adult AM had greater bactericidal activity (p less than 0.01). The bactericidal activity of infant and adult AM against GBS was comparable after 45 min of incubation; infant AM had slightly but significantly greater bactericidal activity with short incubation (15 min; p less than 0.025). The bactericidal activity of abu-MDP-treated infant AM against SA (p less than 0.01) and GBS (p less than 0.05) was greater than that of untreated infant AM and untreated or abu-MDP-treated adult AM. The abu-MDP did not significantly (p greater than 0.2) enhance the antimicrobial activity of adult AM. Catalase, but not superoxide dismutase or mannitol, significantly (p less than 0.005) increased survival of GBS in infant AM; this effect was comparable in abu-MDP-treated and in untreated AM. The abu-MDP-treated infant, but not the adult AM, released more acid phosphatase when triggered by opsonized zymosan than did untreated AM, but superoxide anion release by infant or adult AM was not affected by incubation with abu-MDP.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Age-dependent effects of aminobutyryl muramyl dipeptide on alveolar macrophage function in infant and adult Macaca monkeys. 663 75

Homogenates of the posterior latissimus dorsi muscle, a phasic muscle, were fractionated by a one-step zonal centrifugation technique into four major organelle populations and cytoplasmic constituents. These were: (1) Plasma membrane fragments with a modal equilibrium density of 1.10 and containing 5'-nucleotidase, alkaline phosphodiesterase, p-nitrophenylphosphatase and acid phosphatase (beta-glycerophosphate was used as the substrate). (2) Sarcoplasmic reticular fragments which could be further subdivided into calcium transport vesicles, with a model equilibrium density of 1.16, that exhibited calcium uptake; K+-ATPase; leucyl-bet-naphthylamidase; acid phosphodiesterase; acid phosphatase (using cytidine monophosphate as the substrate); and sarcoplasmic reticular lysosomes, with a model equilibrium density of 1.18, possessing dipeptidyl-aminopeptidase II, cathepsin D, alpha-glucosidase, N-acetyl-beta-glucosaminidase, and NADH oxidase activity. (3) Mitochondria with a modal equilibrium density of 1.21. (4) Catalase-containing vesicles with a modal equilibrium density of 1.22; and cytoplasmic constituents (modal density of 1.25) with phosphorylase, pyruvate kinase, myosin-ATPase, aldolase, and protein and RNA content. The purity of these organelles was equal to or better than previous efforts, with a 30-fold purification achieved for 5'-nucleotidase and alkaline phosphodiesterase. These results lend support to the hypothesis that the sarcoplasmic reticulum of phasic muscle, in addition to its specialized role in excitation-contraction coupling, represents a multifunctional membrane system, and that, similar to the smooth endoplasmic reticulum of other cells, it includes some membrane-bound lysosomal enzymes and NADH oxidase.
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PMID:Isopycnic-zonal centrifugation of plasma membrane, sarcoplasmic reticular fragments, lysosomes, and cytoplasmic proteins from phasic skeletal muscle. 721 87

In the present paper, the involvement of active oxygen species in bone resorption has been studied. In order to compare the production of active oxygen by mouse marrow culture cells, fluorescence due to peroxides reacted with 2,7-dichlorofluorescin was measured. After marrow cells were cultured with 1,25-(OH)2D3 for 8 days, there were tartrate resistant acid phosphatase positive multinucleated cells (TRACP(+)MNCs), TRACP positive mononucleated cells, macrophage-like cells and marrow derived stromal cells. Among these cells, TRACP(+) cells could produce almost the equivalent amount of peroxides as could the macrophage-like cells. In order to examine the role of active oxygen in bone metabolism, the amount of oxidative stress was altered during the culture period in the same marrow culture system. Catalase, a catabolic enzyme of hydrogen peroxide (H2O2), significantly suppressed the formation of TRACP(+)MNCs in a dose dependent manner. This suppression was limited in the early stage of the culture period and was reduced by the addition of exogenous H2O2 to culture. Moreover, when superoxide dismutase, a converting enzyme from superoxide anion to H2O2, was added in this system, the formation of TRACP(+)MNCs was significantly increased. These results strongly suggest that active oxygen species, especially H2O2, may be involved in the regulation of osteoclast formation.
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PMID:Participation of oxidative stress in the process of osteoclast differentiation. 832 62

Mitochondrial fractions isolated from pears (Pyrus communis L.) at the climacteric minimum and peak were subjected to sucrose density gradient centrifugation. The distribution of protein and specific activities of 3 enzymes from this mitochondrial fraction were investigated.Cytochrome oxidase specific activity remained associated with the particulate fraction and increased slightly during the period in which respiration of the whole fruit reached its climacteric peak. Catalase and acid phosphatase specific activity was associated with both the particulate and the least dense region of the gradient and decreased with postharvest ripening.Evidence for several differences between the subcellular behavior of catalase and acid phosphatase from pear tissue compared to their counterparts isolated from mammalian cells is discussed. A general shift of maximum specific enzymic activities and protein distribution to lighter regions of the density gradient occurs with ripening, suggestive of diminution in size or density of intracellular particles.
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PMID:Sucrose density gradient distribution of mitochondrial protein and enzymes from preclimacteric and climacteric pears. 1665 69


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