Olivia Hatcher – Biochemistry – Week 5

This week I mostly focused on data analysis. I used the data I collected last week about Cytochrome C. Using the Index of refraction I found using the refractometer I found the concentration of Urea within the different sample I made. In addition, I used the data collected from the UV Vis machine to find the concentration of the protein in the different samples. I did this by using Beer-Lambert’s law, which states that Absorption = epsilon*concentration*path length, where absorption was the number given by the absorption spectrometer, epsilon was 11200,  and the path length was the length of the cuvette: 1 cm. In addition, I used the fluorescence to determine the fraction of unfolded protein within the samples. When Cyt C is folded, the distance from the donor group (the trp 59) to the acceptor (the heme group) is very small so the energy transfer is completed successfully resulting in quenched fluorescence. That is to say, very little fluorescence. However, as the protein denatures, the distance between the trp 59 and the heme group grows, therefore, there are less successful energy transfers and an increased fluorescence signal. From this data (using the subsequent blanks to correct the data) I created many graphs, and will eventually find the change in Gibbs energy as it relates to the concentration of the denaturant (urea). The next step in data analysis is to fit the curve of fraction unfolded protein v. concentration of urea to an equation to find the Gibbs free energy. This is the refractometer

In addition to data analysis, I created more cyt c samples of a larger urea concentration to finish the curve that I created in the data analysis. Next week I will combine the data and finish the data analysis on cyt c.

Outside of my internship, I went to the Belmont Boardwalk, near mission beach. At the boardwalk there are many rides and arcade games. Since the park was open late, I went at night to take advantage of the smaller lines. On Sunday, I went to Pacific beach.  I am so lucky to be in such a beautiful city where I have access to so many different activities!