Question

An enzyme-catalyzed reaction is conducted in a test tube with a fixed amount of enzyme. Increasing the substrate concentration in the test tube may overcome the effect of which of the following conditions?

a. a saturated enzyme population.
b. denaturation of the enzyme.
c. presence of a fixed amount of an allosteric inhibitor.
d. presence of a fixed amount of a competitive inhibitor

Answer 1

Answer:

d) Presence of a fixed amount of a competitive inhibitor

Explanation:

By increasing the substrate concentration with a fixed amount of enzyme  in an enzyme-catalyzed reaction may over the effect of presence of a fixed amount of competitive inhibitor. As a competitive inhibitor closely resembles with the structure of an enzyme's substrate and due to this close structural similarity, a competitive inhibitor reversibly binds to the enzyme's active site forming an enzyme-inhibitor complex (EI) that is equivalent to enzyme-substrate complex (ES). Increased substrate concentration reverse the effect of competitive inhibitor as at high substrate concentration, all the active sites of the enzyme are filled with substrate making it unavailable for the competitive inhibitor.