Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rats bearing Reuber H-35 or Novikoff hepatomas and mice bearing L1210 or L5178Y murine leukemias exhibited elevated serum levels of fetuin : N-acetylneuraminic acid transferase (EC 2.4.99.1) activity. The serum transferase activity could be correlated with the growth rate of the tumor; in animals bearing the more rapidly growing Novikoff hepatoma, activity was higher than in animals bearing the Reuber H-35 hepatoma. Higher transferase levels were also found in L1210 leukemic mice than in mice with the slightly slower growing L5178Y leukemia. Serum from rats bearing Reuber H-35 hepatoma and mice bearing L1210 murine leukemia had elevated levels of alpha- and beta-glucosidase (EC 3.2.1.20 and EC 3.2.1.21), alpha- and beta-galactosidase (EC 3.2.1.22 and (3.2.1.23), beta mannosidase (EC 3.2.1.25), alpha- and beta-fucosidase (EC 3.2.1.- and EC 3.2.1.38), beta-N-acetylglucosaminidase (EC 3.2.1.30) and acid phosphatase (EC 3.1.3.2); alpha-mannosidase (EC 3.2.1.24), beta-N-acetylgalactosaminidase (EC 3.2.2.-) and beta-xylosidase (EC 3.2.1.37) were not elevated. In animals bearing Reuber H-35 hepatoma, host liver levels of glycosidases, beta-glucuronidase (EC 3.2.1.31) and acid phosphatase were elevated over both the control and the hepatoma values. The data are interpreted to mean that the tumors or various host tissues release large quantities of enzymes into the serum and that enzyme levels in host organs may also be affected by the tumor.
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PMID:Serum and host liver activities of glycosidases and sialyltransferases in animals bearing transplantable tumors. 17 98

Beta 1,4 galactosyl- and alpha 2,6 sialyltransferase (gal-T EC 2.4.1.22 and sialyl-T EC 2.4.99.1) sequentially elongate and terminate complex N-glycan chains of glycoproteins. Both enzymes reside in trans Golgi cisternae; their ultrastructural relationship, however, is unknown. To delineate their respective Golgi compartment(s) we conducted a double label immunofluorescent study by conventional and confocal laser scanning microscopy in HepG2, HeLa, and other cells in presence of Golgi-disturbing agents. Polyclonal, peptide-specific antibodies to human sialyl-T expressed as a beta-galactosidase-sialyl-T fusion protein in E. coli were developed and applied together with mABs to human milk gal-T. In untreated HepG2 and HeLa cells Golgi morphology identified by immunofluorescent labeling of sialyl-T and gal-T, respectively, was nearly identical. Treatment of cells with brefeldin A (BFA) led to rapid and coordinated disappearance of immunostaining of both enzymes; after BFA washout, vesicular structures reappeared which first stained for gal-T followed by sialyl-T; in the reassembled Golgi apparatus sialyl-T and gal-T were co-localized again. In contrast, monensin treatment produced a reversible swelling and scattering of gal-T positive Golgi elements while sialyl-T positive structures showed little change. Treatment with nocodazole led to dispersal of Golgi elements in which gal-T and sialyl-T remained co-localized. Treatment with chloroquine affected Golgi structures less than monensin and led to condensation of gal-T positive and to slight enlargement of sialyl-T positive structures. Sequential recovery from BFA of gal-T and sialyl-T and their segregation by monensin suggest that these enzymes are targeted to different Golgi subcompartments.
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PMID:Double immunofluorescent staining of alpha 2,6 sialyltransferase and beta 1,4 galactosyltransferase in monensin-treated cells: evidence for different Golgi compartments? 769 43

We have investigated the activity of CMP-Neu5Ac:Gal beta 1-3GalNAc alpha-2,3-sialyltransferase (EC 2.4.99.4) in FR3T3 cells transformed by the Ha-ras oncogene in which we have previously demonstrated the higher expression of the beta-galactosidase alpha-2,6-sialyltransferase (EC 2.4.99.1) [21]. We demonstrate that the presence of the activated ras gene decreases the activity of this specific alpha-2,3-sialyltransferase fourfold. According to the kinetic parameters and to mixing experiments, we can assume that this decreased enzymatic activity reflects a decrease in the number of active O-glycan alpha-2,3-sialyltransferase polypeptides in ras-transformed cells. However, no change in the binding of Peanut agglutinin was observed on the cell surface of ras-transformed FR3T3 suggesting that no change in the sialylation of O-glycan core 1 appeared in these cells, although the activity of the alpha-2,3-sialyltransferase was decreased.
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PMID:Sialyltransferase activity in FR3T3 cells transformed with ras oncogene: decreased CMP-Neu5Ac:Gal beta 1-3GalNAc alpha-2,3-sialyltransferase. 835 31