Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2
|
| pubmed:dateCreated |
1991-12-3
|
| pubmed:abstractText |
Connective tissue of the freshwater pulmonate Lymnaea stagnalis was shown to contain galactosyltransferase activity capable of transferring Gal from UDP-Gal in beta 1-3 linkage to terminal GalNAc of GalNAc beta 1-4GlcNAc-R [R = beta 1-2Man alpha 1-O(CH2)8COOMe, beta 1-OMe, or alpha,beta 1-OH]. Using GalNAc beta 1-4GlcNAc beta 1-2Man alpha-1-O(CH2)8COOMe as substrate, the enzyme showed an absolute requirement for Mn2+ with an optimum Mn2+ concentration between 12.5 mM and 25 mM. The divalent cations Mg2+, Ca2+, Ba2+ and Cd2+ at 12.5 mM could not substitute for Mn2+. The galactosyltransferase activity was independent of the concentration of Triton X-100, and no activation effect was found. The enzyme was active with GalNAc beta 1-4GlcNAc beta 1-2Man alpha 1-O(CH2)8COOMe (Vmax 140 nmol.h-1.mg protein-1; Km 1.02 mM), GalNAc beta 1-4GlcNAc (Vmax 105 nmol.h-1.mg protein-1; Km 0.99 mM), and GalNAc beta 1-4GlcNAc beta 1-OMe (Vmax 108 nmol.h-1.mg protein-1; Km 1.33 mM). The products formed from GalNAc beta 1-4GlcNAc beta 1-2Man alpha 1-O(CH2)8COOMe and GalNAc beta 1-4GlcNAc beta 1-OMe were purified by high performance liquid chromatography, and identified by 500-MHz 1H-NMR spectroscopy to be Gal beta 1-3GalNAc beta 1-4GlcNAc 1-OMe, respectively. The enzyme was inactive towards GlcNAc, GalNac beta 1-3 GalNAc alpha 1-OC6H5, GalNAc alpha 1--ovine-submaxillary-mucin, lactose and N-acetyllactosamine. This novel UDP-Gal:GalNAc beta 1-4GlcNAc-R beta 1-3-galactosyltransferase is believed to be involved in the biosynthesis of the hemocyanin glycans of L. stagnalis.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Oct
|
| pubmed:issn |
0014-2956
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
15
|
| pubmed:volume |
201
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
459-65
|
| pubmed:dateRevised |
2007-7-23
|
| pubmed:meshHeading |
pubmed-meshheading:1935942-Animals,
pubmed-meshheading:1935942-Carbohydrate Sequence,
pubmed-meshheading:1935942-Cations, Divalent,
pubmed-meshheading:1935942-Chromatography, High Pressure Liquid,
pubmed-meshheading:1935942-Connective Tissue,
pubmed-meshheading:1935942-Galactosyltransferases,
pubmed-meshheading:1935942-Hydrogen-Ion Concentration,
pubmed-meshheading:1935942-Lymnaea,
pubmed-meshheading:1935942-Magnetic Resonance Spectroscopy,
pubmed-meshheading:1935942-Manganese,
pubmed-meshheading:1935942-Microsomes,
pubmed-meshheading:1935942-Molecular Sequence Data,
pubmed-meshheading:1935942-Submandibular Gland,
pubmed-meshheading:1935942-Substrate Specificity,
pubmed-meshheading:1935942-Swine
|
| pubmed:year |
1991
|
| pubmed:articleTitle |
Identification of a novel UDP-Gal:GalNAc beta 1-4GlcNAc-R beta 1-3-galactosyltransferase in the connective tissue of the snail Lymnaea stagnalis.
|
| pubmed:affiliation |
Department of Bio-Organic Chemistry, Utrecht University, The Netherlands.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|