1. University of Puerto Rico<br />Cayey Campus<br />Jessica Díaz Rivera<br />RISE Program<br />Prof. Elena Gonzalez<br />Paragraph 10: Biofuel Enzyme<br /> Enzymes are typically proteins that act as catalysts, speeding up the vast majority of the chemical reactions that occur in cells. Each type of enzyme has a specific shape that compliments the structure of its substrate. The enzyme Cellobiase is involved in the last step of the process of breaking down cellulose to glucose. Cellulose is a molecule made up of bundled long chains of glucose that are found in plants cell walls. The objective of this experiment is to work with an enzyme (Cellobiase) and alter the environmental conditions to see how affective it is as a catalyst. The experiment that I did was to determine the effect of pH on the reaction rate. We had three cuvettes, each of them labeled with different pH; ‘pH 5’, ‘pH 6.3’ and ‘pH 8.6’. We put 500 microliters of stop solution (a homogeneous mixture of two or more substances that they already provided us) into each cuvette. Later we had to put 250 microliters of 3.0mM substrate and 250 microliters of enzyme in each of the labeled microcentrifuge tubes. After two minutes we transferred 500 microliters of the reaction to the appropriately labeled cuvette containing the stop solution. We used the spectrophotometer to determine the absorbance of each cuvette labeled with different pH. We could analyze that the pH in which the enzyme catalyze with an absorbance of 0.119 is pH 5 because the absorbance of the other pH gave us a negative reading. If the enzyme increases the reaction, the activation energy decreases. To conclude, if the alkalinity increases, the enzyme, Cellobiase, does not catalyze. <br />