Measuring the reactions of the enzymes catecholase in different levels Lab Report

Measuring the reactions of the enzymes catecholase in different levels of pH in different tempereture - Lab Report Example Temperature rise of about 10oC normally doubles or triples the rate of enzymatic reactions. However beyond the optimum temperature the enzyme activity decreases. If catecholase activity is minimally affected at different temperatures and pH then it can be hypothesized that it has a large range of optimal activity. The aim of this experiment was to test the effect of temperature and pH on the enzymatic activity of catecholase. The effect of catecholase enyme at different temperatures, 0 and 37oC were tested at different levels of pH 2, 4, 7 and 12. Three tubes for each pH were set up and labelled A, B and C. To three tubes in each pH 3ml of the pH solution was added and 2ml of banana extract (substrate). To two tubes 1ml of the enzyme (potato extract) was added while the third tube the enzyme was not added and acted as the control. The test tubes were then shaken and put in the appropriate temperature and the optical density measured after three minutes. The reaction rate was the highest at all temperatures at pH 7. At room temperature the reaction rate was the highest in the tube without the enzyme. pH 4 and 12 had the lowest reaction rates at all temperatures. The reaction rates were highest between 0oC and room temperature in the presence of catecholase and lowest at 0oC without the enzyme. Catechol oxidase (catecholase) is a polyphenol oxidase enzyme present in many plants (Aniszewski et al. 2008). It is responsible for catalysing the reaction between oxygen and hydroxylated benzenes leading to the production of quinines and water. The enzyme mediated reaction rate was the highest at physiological pH and at temperatures between zero and room temperature. This shows that the enzyme has a large range of optimal temperatures. However, it has a narrow range of optimal pH. The narrow pH range during which catecholase activity was the highest is due to the effect of pH on the redox