Objectives:
The objective of this lab was to develop a protocol to investigate the effect of an environmental variable on the catalytic function of an enzyme. More specifically, the objective was to perform an experiment in order to test the effect of pH on the function of the enzyme catalase.
Introduction: Enzymes are proteins that act as catalysts for reactions. This simply means that enzymes lower the activation energy required for a reaction to take place, allowing a particular reaction to take place much quicker and easier. Specific enzymes only lower the activation energy for specific reactions, and enzymes are shape-specific. The unique folds of the amino acid chains that make up an enzyme result in the formation of a specifically shaped active site. When the reactants of a reactions, called substrates, fit perfectly into the active site of an enzyme, the enzyme is able to catalyze the reaction. The activity of enzymes is affected by both the concentrations of enzymes present and the concentration of substrate present. As the amount of enzyme present increases, the rate of reaction increases. Furthermore, as the amount of substrate increases, the rate of reaction will initially increases. Most enzymes require specific environmental conditions to be met in order for them to function properly and efficiently. These conditions include temperature, then concentration of salt, and the pH level. If the optimum conditions for an enzyme are altered, the enzyme may denature, or change its shape, and deactivate. As a result, the enzyme would no longer to be able to catalyze the reaction, and the reaction rate would significantly decrease ("Worthington Biochemical Corporation"). Catalase is found in all organisms that use oxygen for their metabolism. The enzyme is found in high concentrations in a organelle in cells called the peroxisome. One of the functions of catalase is to
Cited: 1 Crook, James. "Catalase - An Extraordinary Enzyme."Catalase Website. N.p., 05 Jul 2003. Web. 3 Mar 2012. 2 "Introduction to Enzymes." Worthington Biochemical Corporation. N.p., 27 Feb 2012. Web. 3 Mar 2012.