Glycosciences cover the subfields of chemistry, biology and medicine where sugars play an important role. Glycoresearchers study not only sugar or saccharide molecules but also other biological phenomena or molecules. The word glyco is derived from Greek and means sweet. Saccharides are significant factors in several biological interactions. Carbohydrates have long been known as essential components participating in cellular metabolism. The importance of saccharides (or carbohydrate structures) in animal and human cell biology is shown by the fact that more than half of cellular proteins are glycosylated. Such proteins are called glycoproteins. Part of the glycosylation taking place on the cell surface consists of glygolipids being linked with certain fat molecules or ceramide lipids. Saccharides also appear as free oligomers, for example in breast milk and urine.
Oligo- and polysaccharide chains can be constructed in several different spatial and chemical ways. Compared to proteins, their structural variation is significantly greater, which enables effective packing of information. This is particularly evident in the intra-molecular recognition processes of cells and biomolecules. In addition to animal cells, saccharides appear on surfaces of bacteria and in plant biology. Carbohydrate constructions convey information and, especially as polysaccharides, they also have a structural function.
Saccharides play an important role, for example, in inflammatory events, growth and differentiation, and spreading of cancer cells. Several pathogens use host cell surface saccharides as their recognition and docking target. As examples, the influenza virus and some bacteria in the alimentary tract work in this way. Saccharides are also important in the spreading process of cancer.