Question

Which of the following statements is/are correct regarding the effects of pH on enzyme catalysed reactions?

• A. Direction of the reaction is influenced by $\left[H^{+}\right]$.
• B. Ionization state of dissociating groups on the enzyme is modified.
• C. Ionization state of the substrate is modified.
• D. All of the above

Answer 1

The correct option is D All of the above

The enzyme catalyst reactions are affected by various factors such as pH, temperature, substrate concentration. There is a gradual increase in enzyme activity as pH increases up to a certain point. After this point, there is the rapid decrease in the rate of reaction. The direction of the enzyme catalyst reaction is influenced by the H${}^{+}$ concentration. The change in pH affects the state of ionization of acidic or basic amino acids. The change in pH may result in the modification of the ionization state of the substrate or modification of the dissociating groups on the enzyme. As a result, a substrate either cannot bind to the active site or it cannot undergo catalysis.

Thus, the correct answer is option D.