ENZYME-ASSISTED SYNTHESIS OF ASN-LINKED DIANTENNARY OLIGOSACCHARIDES OCCURRING ON GLYCODELIN-A

The preparation of a series of sialylated and fucosylated N,N'-diacety llactosediamine-type diantennary glycopeptides is reported. By sequent ial enzymatic action of jack bean beta-galactosidase, snail beta 4-N-a cetyl-galactosaminyltransferase, bovine colostrum alpha 6-sialyltransf erase and human milk alpha 3-fucosyltransferase, a diantennary glycope ptide obtained from asialo fibrinogen was converted at a 5-mu mol scal e to a series of structures occurring on the glycoprotein glycodelin A , which potentially inhibit human sperm-egg binding. (C) 1998 Elsevier Science Ltd. All rights reserved.