The enzyme carbonic anhydrase is one of the speediest enzymes known. It catalyzes the rapid conversion of CO₂ gas into the much more soluble bicarbonate ion (HCO₃–). The reaction: CO₂ + H₂O ↔ HCO₃^-+ H⁺ is very important for the efficient transport of CO₂ from tissues, where CO₂ is produced by respiration, to the lungs, where it is exhaled. Carbonic anhydrase accelerates the reaction 10⁷-fold, hydrating 10⁵ CO₂ molecules per second at its maximal speed. What do you suppose limits the speed of the enzyme? Sketch a diagram analogous to the one shown in Figure 3−13 and indicate which portion of your diagram has been designed to display the 10⁷-fold acceleration.

Transcribed Image Text:

number of molecules - molecules with average energy energy required to undergo the enzyme-catalyzed chemical reaction 1 1 energy needed to undergo an uncatalyzed chemical reaction I I 1 1 1 I energy per molecule -