An enzyme is near maximum efficiency when A)its turnover number is near V_max. B)k_cat/K_M is near 10⁸ M^-1s^-1. C)k₁

Question

An enzyme is near maximum efficiency when A)its turnover number is near V_max. B)k_cat/K_M is near 10⁸ M^-1s^-1. C)k₁ << k_-1. D)k_cat/K_M is equal to k_cat. E)K_M is large when k₂ exceeds k₁.

Quizplus · Accepted Answer

Option B states the Michaelis-Menten equation in terms of its constants. When k_cat/K_M is about 10^8 M^-1 sec^-1 or higher, it indicates that the enzyme is functioning at near maximum efficiency. This is because, at this point, the enzyme is very effective at converting substrate to product, and the rate of the reaction is limited only by the concentration of the substrate. Therefore, option B is the best choice. The other options do not accurately describe the state of maximum efficiency for an enzyme.

An Enzyme Is near Maximum Efficiency When