Carbonic Anhydrase Has Two Substrates, Carbon Dioxide and Bicarbonate, Which

Multiple Choice

Carbonic anhydrase has two substrates, carbon dioxide and bicarbonate, which are both converted to carbonic acid. Kinetic data for each is given below. Typical values for K_cat/K_m range from less than 1 mM^-1sec^-1 to as high as 2.8×10⁵ mM^-1sec^-1. What can be said about the K_cat/K_m for CO₂?
Substrate
K_m (mM)
K_cat (sec^-1)
K_cat/K_m (m M^-1sec^-1)
CO₂
HCO₃^-
12
26
1×10⁶
4×10⁵
8) 3×10⁴
1.5×10⁴

A) carbonic anhydrase binds CO₂ well but poorly converts it to carbonic acid
B) carbonic anhydrase binds CO₂ poorly but effectively converts it to carbonic acid
C) carbonic anhydrase binds CO₂ well and converts it to carbonic acid very well
D) carbonic anhydrase binds CO₂ poorly and poorly converts it to carbonic acid
E) the data above is useless for this question