The 3-D structure of an enzyme composed of a single polypeptide chain includes a large substrate-binding domain. It also has a separate binding site for a regulatory molecule. Based on these structural observations the enzyme is most likely regulated by which of the following mechanism?
A) noncompetitive inhibition
B) competitive activation
C) competitive inhibition
D) cooperativity

Question

Quizplus · Accepted Answer

Noncompetitive inhibition involves a regulatory molecule binding to a site other than the active site (an allosteric site), which changes the enzyme's activity. The presence of a separate binding site for a regulatory molecule in the enzyme structure suggests noncompetitive inhibition.

The 3-D Structure of an Enzyme Composed of a Single