ABSTRACT

Recent research in molecular biology has implicated cell surface glycoproteins, with their highly variable arrangements of sugar moieties, as the identifying markers that allow cells to uniquely distinguish individual chemical structures. The macromolecules which exhibit the property of recognition and binding of specific carbohydrate sequences are referred to as lectins. 1 Carbohydrate-mediated recognition reactions allow more combinations of chemically unique receptor sites than are possible with polypeptides. While there are 20 common structural units in the latter case and only nine sugars, glycosidic bonds allow extensive structural branching that is unimportant in peptide bonding. The number of conceivable combinations and permutations of polypeptide structures is thus small compared to that for the highly branched oligosaccharides for which this number approaches 1024. 2