Enzymes are generally named for the reaction they catalyze by adding the suffix ase .
Enzymes mediate every one of the thousands of reactions of cellular metabolism.
The enzyme binds the substrate and while the two are joined, the catalytic action of the enzyme converts the substrate to product. Specificity is based on molecular recognition through structural complementarity . This site is called the active site . It is where S binds and catalysis takes place. The active site is typically a pocket or groove in the enzyme surface, typically formed of relatively few amino acid R residues.