The Level of Protein Structure Primarily Involved in Determining Enzyme

Question

The level of protein structure primarily involved in determining enzyme activity is the
A)primary structure.
B)secondary structure.
C)tertiary structure.
D)quaternary structure.

Accepted Answer

Enzyme activity is primarily determined by the tertiary structure of a protein. This is because the active site of an enzyme, where substrate binding and catalysis occur, is formed by the specific arrangement of amino acids within the tertiary structure. Changes to this structure, such as denaturation or mutations, can greatly affect enzyme activity. While the primary and secondary structure also contribute to the overall shape of a protein, they are less directly involved in enzyme activity. The quaternary structure, which refers to the arrangement of multiple polypeptide chains, can play a role in enzyme activity if subunits are required for proper function, but it is not always relevant to every enzyme.