active site of enzyme

Define active site

The active site (or active center) of an enzyme represents the small region at which the substrate(s) binds and participates in the catalysis.

features of actiev site

1 . The existence of active site is due to the tertiary structure of protein resulting in three dimensional native conformation. 2. The active site is made up of amino acids (known as catalytic residues) which are far front each other in the linear sequence of amino acids (primary structure of protein). 3. Active sites are regarded as clefts or crevices or pockets occupying a small region in a big enzyme molecules. 4. not rigid in structure and shape. 5. active site possesses a substrate binding site and a catalytic site -- latter for the catalysis of the specific reaction.

features of active site

6. The coenzymes or cofactors on which some enzymes depend are present as a part of the catalytic site. 7. The substrate(s) binds at the active site by weak non covalent bonds. 8. Enzymes are specific in their function due to the existence of active sites. 9. The commonly found amino acids at the active sites are serine, aspartate, histidine, cysteine, lysine, arginine, glutamate, tyrosine etc -- serine is the most frequently found. 10. The substrate binds the enzyme (E) at the active site to form enzyme-substrate complex (ES). The product (P) is released after the catalysis and the enzyme is available for reuse