I found the models that we were able to construct in class on Thursday to be very interesting! It was fascinating to see how the hydrogen bonds and different geometric bonds of the elements could affect the shapes of the amino acids so drastically!
I returned back to my research on prions from last week and was fascinated to see that a traditional PrP (prion protein found in mammals) is constructed of three α-helices and a two-strand antiparallel β-sheet, an NH2-terminal tail, and a short COOH-terminal tail. Before having constructed those models in class, I would have had no idea what an alpha-helix or beta-sheet was! Additionally, it is interesting to note that a traditional PrP is 208 amino acids long and has two distinct isoforms: PrPC which is a healthy major prion protein, and PrPSc (the Sc stands for scrapie) which is the infectious structure of a major prion protein.
I have included a picture of the structure in the link of a PrP so that you can see the alpha helices (in green) and beta sheets (in blue) and how they are altered when a PrPC is infected and becomes PrPSc!
http://www.bio.davidson.edu/Courses/Molbio/MolStudents/spring2005/Winter/Prion1new1.htm
I also thought it was great to go back and read about prion proteins again, and see how I understood so much more! I did some research into the infectious version of the protein, whose structure is still undetermined. It’s so interesting that they’ve managed to figure out what the structure of the normal version is, but are still unable to determine the structure of PrPSc and how it forms.