Measuring Enzyme Activity: Yeast Catalase *
| Difficulty | |
| Time Required | Average (6-10 days) |
| Safety | Adult supervision is recommended for this project. |
*Note: This is an abbreviated Project Idea, without notes to start your background research, a specific list of materials, or a procedure for how to do the experiment. You can identify abbreviated Project Ideas by the asterisk at the end of the title. If you want a Project Idea with full instructions, please pick one without an asterisk.
Abstract
Yeast contains an enzyme, called catalase, that acts as a catalyst for the reaction that breaks down hydrogen peroxide into oxygen and water (2H2O2 → 2H2O + O2). Safety note: oxygen is a highly reactive gas, adult supervision recommended for this project. For your background research, be sure that you understand substrate, catalyst, reaction rate, catalase, enzyme saturation and protein denaturation. Use a solution of 3% H2O2 for the substrate. Construct an apparatus that allows you to collect and measure the oxygen gas produced (for a description, see: An Aerobic Exercise: Yeast Metabolism with and without Aeration). Here are some questions you might try to answer with your project: What evidence do you have that the gas you are collecting is oxygen? How does the reaction rate depend on the amount of substrate? At what substrate concentration does the reaction show evidence of enzyme saturation? How does the reaction rate depend on temperature (try increments of 10°C)? At what temperature does the reaction show evidence of protein denaturation? How does the activity of yeast catalase compare to catalase from potato extract or liver extract? How does it compare to the activity of iron oxide? (Gardner, 1999, 97–99; Hamamah, 2005)Share your story with Science Buddies!
Last edit date: 2013-01-10
Bibliography
- Gardner, R., 1999. Science Projects About Kitchen Chemistry. Berkeley Heights, NJ: Enslow Publishers.
- Hamamah, A. A., 2005. "How Do Substrate Amount, Temperature, pH, Enzyme Amount, and Inhibitor Affect Catalase Activity?" California State Science Fair 2005 Project Summary [accessed January 18, 2006] http://www.usc.edu/CSSF/Current/Projects/J0406.pdf.
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