In biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate(s). The substrate binds with the enzyme's active site, and an enzyme-substrate-complex is formed. The substrate is broken down into a product and is released from the active site. The active site is now free to accept another substrate molecule.
A general equation is as follows:
E = enzyme S = substrate(s) P = product(s)
E + S <--> ES --> EP <--> E + P
Note that only the middle step is irreversible.
The content of this page is retrieved from http://en.wikipedia.org/wiki/Substrate_%28biochemistry%29 under GFDL
