Presenter: Kimberly Davidson, Chemistry
Poster: A-5
Mentor: Marina Guenza, Chemistry
In eukaryotic cells, polyubiquitin chains attach themselves to proteins that are ready for proteolysis. When the proteolysis pathway is disturbed, diseases such as cancer can result. This study focuses on the molecular dynamics of diubiquitin on a small time scale. Diubiquitin contains two ubiquitin chains connected by an isopeptide bond between Gly76 and Lys48. We used GROMACS to simulate the protein chain for ~10 ns with an average RMSD of ~0.2 nm. A change in RMSD was observed at ~4 ns indicating a conformational change in diubiquitin. Calculation of T1 and T2 values revealed the theoretical spin-relaxation time for each residue. Further study of diubiquitin will be useful in understanding the proteolysis pathway and how disruption can occur.