Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We immobilized human milk galactosyltransferase covalently to CNBr- and tresylchloride-activated Sepharose. The enzyme was also immobilized non-covalently to Concanavalin A-Sepharose and to monoclonal anti-galactosyltransferase antibodies which were bound via their Fc-fragment to Protein G-Sepharose. With the covalent methods, up to 72% of the enzyme could be bound to the carrier, but more than 90% of the specific activity was lost. In contrast, non-covalent immobilization yielded only about 50% immobilization efficiency, but 21% and 25% of specific activity, respectively, could be recovered. The stability of immobilized galactosyltransferase as compared to native enzyme was considerably increased: at room temperature, 55% of initial immobilized activity was lost after 65 hours compared to 95% of loss of soluble enzyme activity. Immobilized galactosyltransferase was then used for continuous galactosylation of the glycoproteins ovalbumin, endo H-treated yeast invertase and bovine serum albumin-N-acetylglucosamine in a "slurry" reactor. 55%, 35% and 25%, respectively, of all acceptor sites on these glycoproteins could be galactosylated by this method.
 ...
PMID:Immobilization of galactosyltransferase and continuous galactosylation of glycoproteins in a reactor. 213 55

Purified beta-N-acetylglucosaminide beta(1-4)galactosyltransferase and partially purified beta-galactoside alpha(2-6)-sialyltransferase were used to elongate and terminate glycan chains of agalacto-ovalbumin and endo-beta-N-acetylglucosaminidase H-treated yeast invertase in vitro. In the presence of both transferases, 0.1 mol sialic acid was incorporated per mol agalacto-ovalbumin within 24 h. Evidence is presented to show that purification of the galactosylated intermediate increases the efficiency of sialylation. Incorporation of sialic acid into endo-beta-N-acetylglucosaminidase H-treated oligomannose glycoproteins may be useful for in vivo stabilization of these glycoproteins by preventing uptake in liver or reticuloendothelial cells.
 ...
PMID:Galactosyltransferase-dependent sialylation of complex and endo-N-acetylglucosaminidase H-treated core N-glycans in vitro. 308 81

Sequences coding for the cytoplasmic and transmembrane domains were removed from the cDNA of the human Golgi resident membrane protein beta 1,4 galactosyltransferase (gal-T). The remaining sequences coding for the stem and catalytical domains of this glycosyltransferase were fused to sequences coding for the yeast invertase signal sequence. The hybrid was inserted together with a constitutive yeast promoter and a terminator into a E. coli/yeast shuttle vector. Saccharomyces cerevisiae strain BT150 transformed with this new expression vector expressed enzymically active soluble enzyme, whereas no activity was detectable in mock-transformed yeasts. The enzyme product was identified by HPLC analysis and shown to correspond to the expected product N-acetyllactosamine.
 ...
PMID:Expression of soluble active human beta 1,4 galactosyltransferase in Saccharomyces cerevisiae. 819 70