Baseline Peroxidase Reaction Lab Report

For experiment A, we expected that the absorbance values for the baseline peroxidase reaction between guaiacol and hydrogen peroxide would increase over time. This would be due to the increase of color intensity from colorless to brown as the product becomes oxidized towards the end of the reaction. When compared to experiment B, we expected that as the enzyme concentration gets doubled, the absorbance values will increase faster than the baseline over time. The reason why is due to the double concentration of the enzyme that will allow for a better chance of binding to a substrate, which means that the reaction can occur faster. As for half the enzyme concentration, we expected that the absorbance values will increase but at a slower rate

We hypothesized that whenever the inhibitor was introduced into the reaction, the absorbance value would be lower than the baseline enzyme reaction. We believed that this was due to the inhibitor competing with the substrate for active site on the enzyme or altering the configuration of the enzyme depending on the inhibition type. If hydroxylamine was a competitive inhibitor, it would bind to the active site which prevents the substrate from binding. However, if it was noncompetitive inhibition, then the hydroxylamine would bind to the allosteric site of the peroxidase. and the substrate may or may not still be able to bind to the active site. We hypothesized that hydroxylamine was a competitive inhibitor that competes with the substrate for the active site. This was due to the fact that it has a similar structure to hydrogen peroxide, which means that it could fit into the enzyme active site, preventing the substrate from binding. The lab results were as expected since as soon as the inhibitor was introduced to the baseline enzyme catalyzed reaction, the absorbance value decreased from 0.254 to 0.017 as shown in Figure 6. In addition, our results show that the absorbance value of the inhibitor baseline reaction increased from 0.017 to 0.038 as the substrate concentration was doubled. This led us to the conclusion that hydroxylamine is a competitive inhibitor and not a noncompetitive inhibitor. The reason why is due to the fact that if the concentration of the substrate increases, then the effects of the inhibitor reverse if it is competitive. If the inhibitor was noncompetitive, then the increase of substrate would not change the effects due to the inhibitor binding to the allosteric site rather than the active