Active site

As an active center ( engl. active site ) is called in chemistry those sites of a catalyst, of which there is the catalyzed reaction.

Properties

The definition can be applied to two classes of catalysis:

• Heterogeneous catalysis: This describes the active site of a particular arrangement of atoms on the surface of a solid.
• Biocatalysis: Here, the active center of the field describes an enzyme which is responsible for the catalytic activity.

The active site of all previously well-studied enzymes is a pocket- or column- shaped depression of the protein molecule. The resulting increased contact area allows for a stronger and more specific binding of the substrate, partly enantioselectivity. Conversely, the substrate specificity is reduced at a lower contact surface. Binding occurs due to ionic bonds, hydrogen bonds, van der Waals interactions, hydrophobic effects and temporary covalent bonds ( in the transition state ). The active site consists of the substrate binding region and the catalytic center, eg with a catalytic triad, sometimes with a coenzyme. The substrate binding either by the key-lock principle or the induced fit model. Competitive inhibitors to the active site can bind.

An occasionally occurring allosteric center and binding sites for other noncompetitive or uncompetitive enzyme inhibitors do not belong to the active site.

The molecular modeling tries to find about computer -assisted methods in the representation of the active site new agents for the development of drugs. Through a protein design, an active center are specifically changed.