Question

To study the nature of an enzyme, Vmax is not as good a measurement as the catalytic rate constant kcat because ____

A. Vmax is dependent on the enzyme concentration.
B. Vmax is influenced by substrate concentration.
C. kcat is independent of enzyme concentration.
D. kcat provides information about the enzyme-substrate complex stability.

Answer 1

Vmax is not as preferred as kcat for studying enzyme nature because Vmax varies with enzyme concentration, whereas kcat provides a measure of enzymatic efficiency independent of concentration.

Step-by-step explanation:

To study the nature of an enzyme, Vmax is not as good a measurement as the catalytic rate constant kcat because Vmax is dependent on the enzyme concentration. Vmax reaches a plateau when all the enzyme's active sites are saturated with substrate, representing the maximum rate of product formation at a given enzyme concentration. In contrast, kcat indicates the number of substrate molecules converted to product per unit time by a single enzyme molecule when saturated with substrate, providing a true measure of enzyme efficiency independent of enzyme concentration. Moreover, kcat is a fundamental property of the enzyme that reflects its catalytic power without being influenced by enzyme or substrate concentration.