These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Recognition of beta-D-Gal p-(1-->3)-beta-D-Glc pNAc-OR acceptor analogues by the Lewis alpha-(1-->3/4)-fucosyltransferase from human milk.
    Author: Du M, Hindsgaul O.
    Journal: Carbohydr Res; 1996 Jun 05; 286():87-105. PubMed ID: 8925514.
    Abstract:
    The Lewis alpha-(1-->3/4)-fucosyltransferase (E.C. 2.4.1.65) transfers L-fucose from GDP-fucose to OH-4 of the Glc pNAc residue in the disaccharide beta-D-Galp-(1-->3)-beta-D-Glc pNAc-OR [R = (CH2)8COOMe] (1) to give the Lewis-A blood group determinant beta-D-Gal p-(1-->3)-[alpha-L-Fuc p-(1-->4)]-beta-D-Glc pNAc-OR. Five deoxy analogous of 1, as well as its N-propionyl derivative, were chemically synthesized and kinetically evaluated as both substrates and inhibitors for the enzyme from human milk. The unmodified acceptor 1 had Km = 640 microM with Vmax set arbitrarily to 100. The 6-deoxy (Km = 400 microM, V(max) = 90) and N-propionyl compounds (Km = 330 microM, V(max) = 170) remained excellent substrates while the 4-deoxy compound was a very weak competitive inhibitor with Ki = 9 mM. Deoxygenation of OH-2' and OH-4'(of the Gal residue) in 1 had little effect on the activity. The OH-6 group of the Gal residue proved to be critical for recognition by the enzyme since substitution of this group with hydrogen led to an inactive compound.
    [Abstract] [Full Text] [Related] [New Search]