| Oligosaccharides play a key role in the cell recognition process. They may be covalently linked to proteins and lipids and are ubiquitous in their distribution. In multicellular organisms, most cell surfaces are virtually covered with polysaccharides, which are attached either to proteins or lipids in the cell membrane. In nature, oligosaccharides are synthesized by glycosyltransferases. These enzymes transfer monosaccharides from nucleotide sugars (donor substrates) to hydroxyl groups on appropriate carbohydrates (acceptor substrates). |
