Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.21 (beta-glucosidase)
 3,280 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A membrane-bound alpha-L-fucosyltransferase, which is involved in the synthesis of a developmentally regulated carbohydrate antigen, SSEA-1, was purified about 2000-fold from F9 embryonal carcinoma cells. The procedures used were solubilization with Triton X-100, column chromatography on SP-Sephadex, DEAE-Sephadex, RCA-agarose and on GDP-agarose. Upon sodium dodecyl sulfate gel electrophoresis, the purified preparation gave a protein band with a relative molecular mass of 65 000. The optimum pH of the enzyme was between 6.0 and 7.0 and the Km toward N-acetyllactosamine was 0.55 mM. The enzyme was active with asialofetuin, but not with intact fetuin. Susceptibility of the product to alpha-L-fucosidase I from almond emulsin verified that the enzyme transferred fucose to C-3 hydroxyl of N-acetylglucosamine in the N-acetyllactosamine structure. Activities of beta-galactoside alpha 1----2-fucosyltransferase and N-acetylglucosaminide alpha 1----4-fucosyltransferase acting on synthetic substrates were not detected in the purified enzyme nor in the crude extract of F9 cells. PYS-2 parietal endoderm cells lacked all the fucosyltransferases mentioned above.
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PMID:Purification and properties of N-acetylglucosaminide alpha 1----3-fucosyltransferase from embryonal carcinoma cells. 242 30

A beta-galactoside alpha 1 leads to 2 fucosyltransferase has been solubilized from porcine submaxillary glands and purified 124,000-fold to homogeneity by repeated affinity chromatography on GDP-hexanolamine agarose. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of the purified enzyme revealed two electrophoretic species with apparent Mr = 60,000 and 55,000. The two enzyme species have not been completely resolved, but both appear to be active forms of the fucosyltransferase with approximately equal specific activities. Glycosidase digestion of the fucosylated products with the alpha 1 leads to 2-specific fucosidase from Clostridium perfringens and the alpha 1 leads to 3/alpha 1 leads to 4-specific fucosidase from almond emulsin indicates that the enzyme forms exclusively the Fuc alpha 1 leads to 2Gal linkage with a variety of acceptor substrates. A GDP-fucose hydrolase activity co-purifies with the fucosyltransferase. Identical rates of thermal inactivation and co-migration on gel electrophoresis under nondenaturing conditions suggest that the two activities are due to a single enzyme species.
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PMID:Purification to homogeneity of H blood group beta-galactoside alpha 1 leads to 2 fucosyltransferase from porcine submaxillary gland. 624 5

The radical C-glycosidation of (-)-(1S,4R,5R, 6R)-6-endo-chloro-3-methylidene-5-exo-(phenylseleno)-7-ox abi cyclo[2. 2.1]heptan-2-one ((-)-4) with 2,3,4, 6-tetra-O-acetyl-alpha-D-mannopyranosyl bromide gave (+)-(1S,3R,4R, 5R,6R)-6-endo-chloro-5-exo-(phenylseleno)-3-endo-(1',3',4', 5'-tetra-O-acetyl-2', 6'-anhydro-7'-deoxy-D-glycero-D-manno-heptitol-7'-C-yl)-7-oxabi cyc lo[ 2.2.1]hept-2-one ((+)-5) that was converted into (+)-(1R,2S,5R, 6R)-5-acetamido-3-chloro-2-hydroxy-6-(1',3',4',5'-tetra-O-acetyl)-2', 6'-anhydro-7'-deoxy-D-glycero-D-manno-heptitol-7'-C-yl)cyclohex -3-en- 1-yl acetate ((+)-10) and into (+)-(1R,2S,5R, 6S)-5-bromo-3-chloro-2-hydroxy-6-(1',3',4',5'-tetra-O-acetyl-2', 6'-anhydro-7'-deoxy-D-glycero-D-manno-heptitol-7'-C-yl)cyclohex -3-en- 1-yl acetate ((+)-19). Ozonolysis of (+)-10 and further transformations provided 2-acetamido-2,3-dideoxy-3-C-(2', 6'-anhydro-7'-deoxy-D-glycero-D-manno-heptitol-7'-C-yl)-D-galac tos e (alpha-C(1-->3)-D-mannopyranoside of N-acetylgalactosamine (alpha-D-Manp-(1-->3)CH(2)-D-GalNAc): 1). Displacement of the bromide (+)-19 with NaN(3) in DMF provided the corresponding azide ((-)-20) following a S(N)2 mechanism. Ozonolysis of (-)-20 and further transformations led to 2-acetamido-2,3-dideoxy-3-C-(2', 6'-anhydro-7'-deoxy-D-glycero-D-manno-heptitol-7'-C-yl)-D-talose (alpha-C(1-->3)-D-mannopyranoside of N-acetyl D-talosamine (alpha-D-Manp-(1-->3)CH(2)-D-TalNAc): 2). The neutral C-disaccharide 1 inhibits several glycosidases (e.g., beta-galactosidase from jack bean with K(i) = 7.5 microM, alpha-L-fucosidase from human placenta with K(i) = 28 microM, beta-glucosidase from Caldocellum saccharolyticum with K(i) = 18 microM) and human alpha-1, 3-fucosyltransferase VI (Fuc-TVI) with K(i) = 120 microM whereas it 2-epimer 2 does not. Double reciprocal analysis showed that the inhibition of Fuc-TVI by 1 displays a mixed pattern with respect to both the donor sugar GDP-fucose and the acceptor LacNAc with K(i) of 123 and 128 microM, respectively.
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PMID:The C-disaccharide alpha-C(1-->3)-mannopyranoside of N-acetylgalactosamine is an inhibitor of glycohydrolases and of human alpha-1,3-fucosyltransferase VI. Its epimer alpha-(1-->3)-mannopyranoside of N-acetyltalosamine is not. 1089 Nov 23