The Effects of Temperature, pH, Enzyme Concentration , and Substrate Concentration on Catecholase
Enzymes are biological proteins that speed up the reaction rate of a chemical reaction. They work in the human body by lowering activation energy making certain that reactions will initiate. For every action, there is an equal and opposite reaction. In this case, factors that influence the activity of an enzyme are called modulators. If modulators activate enzymes the reaction rate catalyzed will significantly increase, but if the modulator inactivates enzymes the reaction rate catalyzed will significantly decreased (Silverthorn, 2004). The potentially disastrous influence of ...view middle of the document...
Enzyme concentration affects the rate of enzymatic reactions. Without enzymes reactions can go very slowly, but with enzymes the rate is directly proportional to the amount of enzyme that is present. In addition, these reactions will only increase if the substrates present are in excess amounts. Cells can alter the amount of enzymes by influencing their synthesis and breakdown. If enzyme synthesis exceeds breakdown, enzymes accumulate and the speed of catalyzation increases; if enzyme breakdown exceeds synthesis, the concentration of enzyme decreases along with reaction rate. In the event that the amounts are equal there is still a turnover of enzymatic molecules. (Silverthorn, 2004) Substrate concentration affects the rate of enzymatic reactions. At lower substrate concentrations, the reaction rate is strictly proportional to the substrate concentration; but, once the substrate molecule concentrations increase beyond a certain level, there are no more binding sites available for them. This is called saturation, when enzymes catalyze as fast as they can, and reaction rate reaches its maximum potential. Without substrate, enzymes cannot function, and without the appropriate amount of substrate, the velocity of the reactions would take place very slowly (Silverthorn, 2004). The purpose of the study was to observe the activity of enzymes and catecholase when temperature, pH, enzyme and substrate concentrations are increased and or decreased. Catecholase is an enzyme contained in some fruits and vegetables that bind to the substrate Catechol. Catecholase facilitates a reaction between Catechol and Oxygen. In the presence of Oxygen, Catechol is oxidized ( 2 hydrogen molecules are removed) thus creating Benzoquinone. Benzoquinone molecules link to form chain that structure the backbone of the red and brown melanoid pigments that causes the darkening in bruised fruit (Helms, Kosinski, and Cummings, 1998). The Hypothesis: If the temperature is 24°C the enzymes will be most productive. At a pH of 7 the reactions will perform at an optimum level.
Hypothesis 1. At 24°C the catecholase will display the most productivity. 2. pH 7 will showcase an optimal range for catecholase activity. 3. The higher the concentration of enzyme, the more optimal it is for enzyme activity to take place. 4. The higher the concentration of substrate, the more enzymatic activity will result until there is no more enzyme.
Materials and Methods
The Effects of Temperature on Enzyme Activity Three test tubes had 3ml of pH 7 phosphate buffer added. Next, one test tube was placed in an ice bath at 10°C; another tube was placed in a test tube holder at 24°°C; and a final tube was placed in a beaker of 50°C water. The buffers in the test tube were allowed 10 minutes to reach 10°C in the ice bath, 24°C in the test tube holder, and 50°C in the beaker of warming water. One test tube containing potato juice was put in the warm water beaker. Also, one test tube containing Catechol was...