Glycoside hydrolase

Glycosidases ( EC 3.2.1. ) Glycosidases also belong to the enzyme class Hydrolases. Glycosidases are ubiquitous enzymes in all kingdoms (plants, animals, fungi and protists ) are found.

A glycosidase catalyzes reversibly the hydrolysis of a glycosidic bond in a glycoside, with a sugar ( " Glycon " ) and the so-called " aglycone " to be released under consumption of a water molecule. They are usually more or less specific to the abzuspaltenen sugar, the nature of the aglycone, however, plays a minor role. Since the equilibrium of the reaction is on the side of the cleavage products, no power supply is necessary. Under special laboratory conditions but can this equilibrium reaction for the synthesis of synthetically difficult to access glycosides exploit.

Glycosidases are common as digestive enzymes. These glycosidases are rather non-specific, so a fairly wide range of glycosides can hydrolyze. Carbohydrates play addition to its function as an energy source but also in biochemical signaling processes such as cell communication play an important role. In the construction of complex carbohydrate structures on the cell surface individual monosaccharides are cleaved by highly specific glycosidases in intermediate steps again.

The structure of glycosides is carried out by usually very specific glycosyltransferases, by supplying energy.

The pH optimum of glycosidases is for insects of various orders between pH 4.0 and pH 7.0. In many plants, however, the pH optimum of around pH 5.0 is located entirely in the acidic range.