A series of enzymes catalyze the reactions in the metabolic pathway X → Y → Z → A. Product A binds to the enzyme that converts X to Y at a position remote from its active site. This binding decreases the activity of the enzyme. Based on its interaction with the enzyme that converts X to Y substance A is best described as ________.
A) an allosteric inhibitor
B) a substrate
C) a metabolic intermediate
D) a competitive inhibitor

Question

Quizplus · Accepted Answer

Substance A is an allosteric inhibitor because it binds to a site on the enzyme that is remote from the active site, leading to a decrease in the enzyme's activity. This is characteristic of allosteric regulation, where the binding of a molecule at one site affects the activity of the enzyme at a different site.

A Series of Enzymes Catalyze the Reactions in the Metabolic