Catalase Lab Report

Catalase, by definition, is the enzyme that decomposes potent H2O2 into harmless H2O and O2 (Sherwood 2016). Many factors such as the ones analyzed in this lab contribute to the overall rate of the chemical reaction. The first variable, enzyme concentration (Figure 2.), was expected to steadily increase the reaction velocity as more catalase was added. This is because Enzyme activity is generally greatest when substrate concentration is unlimiting (Worthington Biomedical Corporation). Since the substrate given was much greater in amount compared to the enzyme, it was expected that the enzyme would be directly proportional to the reaction velocity. The results of the effect of substrate concentration on catalase activity (Figure 3.) also matched the expectations of the experiment. It was assumed that when the maximum velocity was reached, all of the available enzyme had been converted to the enzyme-substrate intermediate. We can tell from the figure that the maximum velocity reaches approximately 100 O2/min before all of the enzyme had been converted to the enzyme substrate complex (Worthington Biomedical Corporation).

This observation matched our figure, with the reaction velocity reaching 100 O2/min when the pH was at 7.0 (neutral level). While other enzymes are most effective at different pH levels, the tertiary structure of the catalase is what makes it the most effective at neutral level. The function of a protein depends on its tertiary structure. If this is disrupted, the protein is said to be denatured, and it loses its activity (Enzymes). After passing neutral level, catalase denatures and loses some of its catalytic