Enzüümsubstraat

Enzüümsubstraat refers to the molecule upon which an enzyme acts. Enzymes are biological catalysts, typically proteins, that accelerate the rate of chemical reactions. Without an enzyme, these reactions would occur too slowly to sustain life. The specific molecule that an enzyme binds to and chemically modifies is called its substrate. The region on the enzyme where the substrate binds is known as the active site.

The interaction between an enzyme and its substrate is often described by models such as the lock-and-key model or the induced-fit model. In the lock-and-key model, the active site has a rigid shape perfectly complementary to the substrate. The induced-fit model, a more widely accepted view, suggests that the active site is flexible and changes its shape slightly upon substrate binding to achieve a tighter fit. This binding is usually non-covalent, involving attractions like hydrogen bonds and van der Waals forces.

Once bound, the enzyme facilitates the conversion of the substrate into one or more products. After the reaction is complete, the products are released from the active site, and the enzyme is free to bind to another substrate molecule and repeat the catalytic cycle. The specificity of enzymes for their substrates is crucial for regulating metabolic pathways and maintaining cellular functions. Many factors, including temperature, pH, and the presence of inhibitors or activators, can affect the rate at which an enzyme binds to and acts upon its substrate.