Structure, function and metabolism of sialic acids

Sialic acids represent a family of sugar molecules with an unusual and high ly variable chemical structure that are found mostly in the terminal positi on of oligosaccharide chains on the surface of cells and molecules. These s pecial features enable them to fulfil several important and even diametrica l biological functions. Because of the great importance of sialic acids. it is also worth having a look at their metabolism in order to get an idea of the intimate connection between structure and function of these fascinatin g molecules and the often serious consequences that result from disturbance s in the balance of metabolic reactions. The latter call be due to genetic disorders that result in the absence of certain enzyme activity, leading to severe illness or even to death.