Effect of pH on the activity of potato catalase IntroductionCatalase is like most enzymes affected like pH changes. Catalase occurs in many plant and animal tissues, it breaks down hydrogen peroxide into water and oxygen. Hydrogen peroxide is a toxic so the expected pH level which the catalase can work under would be under pH 7, acidic solutions as hydrogen peroxide is acidic.Hypothesis The rate of enzyme activity (catalase breaks down hydrogen peroxide) would increase closer to the optimum pH level and then decrease once the optimum pH level is exceeded. The rate of enzyme activity would be higher at lower pH levels, more gas would be evolved due to the decomposition of hydrogen peroxide by the enzyme catalase.At pH levels which are higher or lower than the optimum pH, the enzyme would denature. This is because the H+ or OH- ions of the solution will interact with the amino acids in the enzyme, breaking bonds such as the hydrogen bonds between the R groups, the ionic bonds between the charged R groups and the hydrophilic interactions within the globular protein (enzyme) disrupting the enzymes tertiary structure causing it to lose the shape of the active site, which is specific to a specific substrate. Without the specific shape of the active site, the enzyme is non functional (cannot be as a catalyst).The substrate which the enzyme is catalyzing cannot bind onto the active site and the enzyme-substrate complex cannot be achieved, which makes the enzyme non functional.

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