Alex Rocha
Texas State University
Abstract
If you’ve ever left a cut up apple out for long, you’ll notice that after a while, it will turn brown. The reason for this is an enzyme named catechol oxidase, a ubiquitous plant enzymes containing a dinuclear copper center (Klabunde, Eicken, Sacchettini, & Krebs, 1998). In this experiment, we used two different chelators, ethylene diamine tetraacetic acid and phenylthiourea to test which would stop the effects of catechol oxidase on potato cells by testing the change in absorbency over time. Our data supported our hypothesis that EDTA would have a greater change in absorbency over time than PTU. Environmental Parameters of Enzyme Activity
Introduction
In this experiment, we used potato cells (CO) to act as …show more content…
The first solution was tube 1 which was made with 1 mL of EDTA, 1 mL of CO, and 5 drops of CAT. Tube 2 was made with 1 mL of PTU, 1 mL of CO, and 5 drops of CAT. Tube 3 was made with 1mL of distilled water, 1 mL of CO, and 5 drops of CAT. After mixing each solution and putting a piece of Parafilm on Tube 1, we set tube 3 as our blank and then measured the change in absorption at 400nm of both tube 1 and tube 2 every two minutes for a total of twenty minutes.
Results
The results of our experiment showed the solutions in both tube 1 and tube 2 increasing in absorbency in the first eight minutes but then tube 1 continued to increase while tube 2 began to balance out. Tube 3, our blank, managed to stay at 0nm the entire twenty minutes. From this data, we can conclude that our hypothesis was supported that EDTA had a greater change in absorption over PTU.
Figure 1. Change in absorbency over time in tubes 1, 2, and 3.
Discussion
Our hypothesis was supported by our data that EDTA would have a greater change in absorbency over time than