Protein misfolding is a process in which a chain of amino acids comes together in a form that causes the quaternary structure of a protein to be nonfunctioning. These misfolded proteins can aggregate with other misfolded proteins to create globules that can be the cause of many diseases, such as amyloidosis. In studying how a protein unfolds, one can observe the mechanisms by which a protein folds and ultimately determine where sources of misfolding can occur.<br/>This experiment was a comparative investigation of unfolding transitions in lysozyme and cytochrome C employing continuous wave absorption and fluorescence spectroscopy. Naturally occurring tryptophan residues in both proteins were used as an intrinsic spectral probe. Lysozyme and cytochrome C samples were unfolded via the addition of varying concentrations of denaturant to observe the effect of denaturation on tryptophan fluorescence. The proteins were also placed in different pH environments to observe tryptophan fluorescence. The energy barriers for protein transitions during unfolding were measured by observing the line widths and Stokes shift of the fluorescence spectra for each discrete protein state along the unfolding pathway. The spectral profiles were directly correlated to the changes in the tryptophan environment during the unfolding process.

Comparative study of unfolding states of lysozyme and cytochrome C employing continuous-wave spectroscopy

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.