Cofactor And Enzyme Reaction

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Introduction What are enzymes and how do they affect reactions? Enzymes force reactions, in cells, to maintain a speed necessary for life. Enzymes can also be considered catalysts because they require the reactions to arise faster without themselves changing. For this experiment, the substrate in the enzymatic reaction was sucrase, and it will be causing sucrose to change resulting in the following equation:
Sucrose → Glucose + Fructose
Where the arrow is in the equation indicates the enzyme, sucrase, used to speed up the reaction. In the experiment conducted we were looking for the effect of a cofactor that could have impacted enzyme activity. A cofactor is required for enzymes to function properly. In order to catch sight of the reaction
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Before anything can be done in this experiment the spectrophotometer must be turned on and warmed for approximately fifteen minutes in order to get an accurate measurement. The spectrophotometer needs to be set on 540 nm because it corresponds with green and green is absorbed by benzoquinone. While the spectrophotometer is warming up, the instructor is preparing a catacholase enzyme solution using white potatoes. She must first cut off all of the skin on the potato, using a knife, because the potato is brown meaning that it could confuse the spectrophotometer into thinking that it is benzoquinone. That would result in an error with the experiment. For this experiment only half of the potato is used because if the entire potato were to be used, then it would be an extremely fast reaction, making it difficult for the reaction to be observed. Next the instructor will chop the potato into little pieces preparing it to be blended. Chopping the potato will help to minimize the heat the blender will use. If massive chunks were used, then the blender would use more heat to help the blending process and denature the proteins in the potato. Another way to help minimize the heat used is to use a chilled blender. When the potatoes have been put into the blender, the instructor will then add 500 milliliters of chilled, distilled water. The water is distilled because is a …show more content…
There seemed to be an error in the experiment conducted, which will be later discussed. In order to show what should have happened, the absolute value was taken of the answers using the numbers that were read from the spectrophotometer. For example, in the PTU test tube the amount after ten minutes subtracted from the amount after twenty minutes gave the answer of -0.023, but instead, and instructed by our teacher, we took the absolute value and said it was 0.023. The formula used to display this is:
Total = Absorbency at 20 minutes - Absorbency at 10 minutes
An easier way to view this is in Figure 1.1 where it shows what should have been closer to the correct answers. EDTA did seem to have inhibited the reaction some, but the chelating agent, PTU, had the smallest reaction rate making copper the correct cofactor. The trend in the data is that the two chelating agents used to bind copper both had smaller reaction rates than the EDTA, used to bind Magnesium and Calcium. The color change was seen the most in the test tube containing EDTA. It went from colorless to a dark orange color. The other test tubes had only a slight color change. The higher the concentration of benzoquinone the more the color will change from colorless to

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