Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.52 (PNGase F)
 1,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Asn-linked oligosaccharides of the pituitary hormone lutropin (LH) contain both sulfate and GalNAc. Bovine pituitary explants incorporate [3H]glucosamine, [3H]mannose, [3H]fucose, and [35S]sulfate into the Asn-linked oligosaccharides of LH. Endoglycosidase F or N-glycanase releases the [3H]glucosamine- and [3H]mannose-labeled oligosaccharides from the protein, which resolve on anion-exchange high pressure liquid chromatography as neutral (S-0), mono- (S-1), and disulfated (S-2) species. Based on sequential enzyme digestion, methylation, periodate oxidation, and nuclear magnetic resonance studies, the proposed structure for S-2 is as follows: formula see text. Sulfate is confined to position 3 or 4 of GalNAc based on periodate and methylation data and can be removed by methanolysis. The presence of beta-linked GalNAc at a position typically occupied by Gal has not previously been observed.
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PMID:Structural elucidation of the disulfated oligosaccharide from bovine lutropin. 299 25

The major sulfated protein of the mouse pancreatic acinar cell, gp300, has been identified and characterized with monoclonal and polyclonal antibodies. gp300 is a glycoprotein of M(r) = 300,000 which contains approximately 40% of metabolically incorporated [35S]sulfate in the acinar cell. Sulfate on gp300 is resistant to hot 1N HCl, but sensitive to alkaline hydrolysis, demonstrating that the sulfate is carbohydrate-linked rather than tyrosine-linked. gp300 metabolically labeled with [3H]glucosamine and [35S]sulfate was chemically and enzymatically treated followed by Bio-Gel P-10 gel filtration. Both labels were resistant to treatments which degrade glycosaminoglycans. Treatment of dual-labeled gp300 with PNGase F to cleave N-linked oligosaccharides released approximately 17% of [3H] and little [35S]. Mild alkaline borohydride treatment after removal of N-linked sugar released the remainder of both labels, indicating the presence of sulfated O-linked oligosaccharides. Biosynthesis studies and PNGase F digestion indicate that the core protein is approximately 210 kDa, with apparent contributions of approximately 35 kDa N-linked sugar, and approximately 55 kDa O-linked sugar. Lectin blotting and glycosidase digestion demonstrated the presence of Gal beta(1-3)GalNAc and sialic acid alpha(2-3)Gal in O-linked oligosaccharide, and Gal beta(1-4)GlcNAc in N-linked oligosaccharide. Immunolocalization and subcellular fractionation showed that gp300 is a peripheral membrane protein localized to the lumenal face of the zymogen granule membrane. gp300 was not secreted in response to hormone stimulation of acini, so it is not a secretory product. Immunoblot analysis showed that gp300 is present in other gastrointestinal tissues and parotid glands. Localization of this nonsecreted sulfated glycoprotein to exocrine secretory granule membranes suggests that gp300 may have a role in granule biogenesis.
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PMID:Characterization of the major sulfated protein of mouse pancreatic acinar cells: a high molecular weight peripheral membrane glycoprotein of zymogen granules. 787 32

The N-glycans have been removed by peptide-N-glycosidase F (PNGase F) from purified human non-secretory RNases derived from kidney, liver and spleen. The spleen RNase was purified by two procedures, one of which did not include the usual acid treatment step (0.25 M H2SO4, 45 min, 4 degrees C), to determine if acid treatment alters the carbohydrate moieties. The N-glycans of the RNases were fractionated by Bio-Gel P-4 chromatography and analysed by 600 MHz 1H-NMR spectroscopy and electrospray mass spectrometry. All four non-secretory RNase preparations contained the following structures: [formula: see text] The relative amounts of the trisaccharide, pentasaccharide and hexasaccharide appeared to vary slightly in the different tissue RNases. The overall results indicate: (i) that acid treatment during purification does not alter the N-glycans of non-secretory RNases; (ii) that the N-glycans from kidney, liver and spleen non-secretory RNases are very similar, if not identical, to one another, but different from the N-glycan structures reported for secretory RNase.
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PMID:Human non-secretory ribonucleases. II. Structural characterization of the N-glycans of the kidney, liver and spleen enzymes by NMR spectroscopy and electrospray mass spectrometry. 835 50