Question

How are the kinetics of a thymidylate synthase-catalyzed reaction affected by 5-Fluorouracil?

a) Increased Vmax
b) Decreased Km
c) Competitive inhibition
d) Noncompetitive inhibition

Answer 1

The kinetics of a thymidylate synthase-catalyzed reaction are affected by 5-Fluorouracil through decreased Km.

Step-by-step explanation:

The kinetics of a thymidylate synthase-catalyzed reaction are affected by 5-Fluorouracil through b) decreased Km.

5-Fluorouracil is a competitive inhibitor of thymidylate synthase, which means it competes with the substrate for binding to the active site of the enzyme. This leads to a higher concentration of the inhibitor being required to achieve the same reaction rate, resulting in a decrease in the apparent Km value.

5-Fluorouracil does not affect the Vmax value nor does it cause noncompetitive inhibition.