Glycoproteins

Glycoproteins (obsolete. Glycoproteins ) are two-component proteins in which the protein ( peptide ) part of the molecule is covalently linked to one or more groups of hetero-oligosaccharides . In addition to glycoproteins, proteoglycans and glycosaminoglycans also exist.

Monosaccharides associated with a particular protein can be different: it can be glucose , fucose , mannose , glucosamine , galactosamine , xylose , sialic acids , galactose , etc.

These or other monosaccharides associated with the protein change the biochemical and immunological properties of the protein, its spatial configuration, etc. An important particular case is the binding of proteins to sialic acid, leading to the formation of sialoglycoproteins. In typical cases, it is binding to sialic acid that determines the increase in T1 / 2 protein in blood plasma .

Glycoproteins are an important structural component of the cell membranes of animals and plant organisms. Most protein hormones belong to glycoproteins. The glycoproteins of erythrocyte membranes, specifically glycosylated by certain carbohydrate residues, but having a homologous protein part, determine the blood group in humans . Also, glycoproteins are all antibodies , interferons , complement components, plasma proteins , milk, receptor proteins, etc.