Enzyme Activity

Enzymes                        June 8th, 2017

3D, Globular, Catalytic Proteins

H2O2 → (Catalase) →  H20 + 02

Objective: To investigate the substance’s spontaneous reaction

Part 1: Spontaneous Decomposition of Hydrogen Peroxide

• Prediction: A small amount of oxygen will release at a small rate.
• Results: The oxygen levels stayed about the same.

Part 2: Enzyme- Catalyzed Breakdown of Hydrogen Peroxide

What is the effect of catalase on the breakdown of hydrogen peroxide?

• Hypothesis: If a catalase is added to the reaction, then a greater amount of oxygen will be release.
• Prediction: If the hypothesis is true, then more yeast cells will yield a greater amount of oxygen released.
• Results: Bubbles were observed as oxygen gas was released.
• Conclusion: The hypothesis was supported because the amount of oxygen present in the container increased.

Part 3: Effects of pH on Enzyme Activity

What is the effect of pH on catalase activity?

• Hypothesis: If the pH is changed, then the enzyme will denature.
• Prediction: If the hypothesis is true, then production of oxygen will not occur.
• Prediction for yeast in a basic environment: A basic environment was unfavorable for the catalyst reaction to occur in. It prevented the catalyst from working properly.
• Prediction for yeast in an acidic environment: An acidic environment will cause gas to generate. The catalyst reaction may still occur, but it will take longer because it will take more time to achieve the energy of activation.
• Conclusion: The hypothesis was supported in conjunction with data provided from others classes. The hypothesis that if the pH is changed, then the enzyme will denature would not be measurable. The lack of change during the reaction suggests that the substrate was not reacting with the catalyst.

Part 4: Effects of Temperature on Enzyme Activity

What is the effect of temperature on catalase activity?

• Hypothesis: This experiment was performed by other groups
• Prediction: This experiment was performed by other groups
• Results: This experiment was performed by other groups
• Conclusion: This experiment was performed by other groups

Table 1: Results of Investigations of the Effect of pH and Temperature on Catalase Activity

Data Run #	Setup	Minimum % Oxygen	Maximum % Oxygen	Change in [Oxygen]	Rate of Reaction (%/s)
1	Spontaneous combustion	20.99	21.05	0.06	0.000200
2	Enzyme catalyzed	20.80	23.91	3.11	0.0103
3A	Increased pH	20.79	20.82	0.03	0.000100
3B	Decreased pH	20.19	22.53	2.34	0.000780
4A	Increased temperature
4B	Decreased temperature