Enzyme Kinetics - pH

Effect of pH



The Experiments

The effect of pH on the rate of enzyme action will be determined by performing five experiments:

1. Two ml of catalase solution mixed with two ml of H2O2 adjusted to a pH = 2.

2. Two ml of catalase solution mixed with two ml of H2O2 adjusted to a pH = 4.5.

3. Two ml of catalase solution mixed with two ml of H2O2 (pH = 7).

4. Two ml of catalase solution mixed with two ml of H2O2 adjusted to a pH = 9.

5. Two ml of catalase solution mixed with two ml of H2O2 adjusted to a pH = 12.

Notice that the only experimental variable being changed is the pH at which the reaction is performed.


Results

Using the data below prepare a graph with pH as the independent variable (x-axis) and rate of O2 formation in mls/sec as the dependent variable (y-axis). From this graph estimate the optimum pH for catalase.

experiment
# 		pH of
solution 		see results
1 2
2 4.5
3 7
4 9
5 12