SYNTHESIS OF ARTIFICIAL GLYCOCONJUGATE POLYMERS STARTING FROM ENZYMATICALLY SYNTHESIZED OLIGOSACCHARIDES AND THEIR INTERACTIONS WITH LECTINS

Styrene derivatives substituted with N-linked beta-anomeric oligosacch arides were synthesized via a simple two-step procedure starting from three enzymatically prepared oligosaccharides: N-acetyllactosamine (Ga l beta 1-4GlcNAc), N-acetylisolactosamine (Gal beta 1-6GlcNAc), and 4' -galactosyllactose (Gal beta 1-4Gal beta 1-4Glc) Their home-and copoly merization with acrylamide using 2,2'-azobisisobutyronitrile as an ini tiator in dimethyl sulfoxide at 60 degrees C gave the corresponding gl ycopolymers. Binding between glycopolymers and lectins was investigate d by means of hemagglutination inhibition experiments, The inhibition of RCA(120) lectin-induced hemagglutination by N-acetyllactosamine-car rying homopolymer was about 10(3) times stronger than that of the olig osaccharide itself, The enhanced binding capacity with lectins can be explained in terms of a multivalent or cluster effect along the polyme ric chain, In some combinations between lectins and polymers, the copo lymers inhibited hemagglutination more strongly than the homopolymers did, N-Acetyllactosamine-carrying glycopolymer showed about 3 X 10(3) times weaker inhibition of DSA lectin-induced hemagglutination than th e different type of N-acetyllactosamine-carrying glycopolymer which ha s an O-linked beta-anomeric phenyl aglycon of each repeating unit alon g a polyacrylamide backbone.