Ethan Jeong Rose Hills
Single Molecule Force Spectroscopy of Protein Folding Intermediates
Despite machine learning advances in predicting protein structure from sequence, how proteins fold from sequence to native structure remains unclear. My research focuses on a novel single molecule force spectroscopy method using optical tweezers to study the folding and unfolding intermediates of a synthetic beta barrel, which is an ancient and conserved protein fold. Variants each containing a segment of eighteen glycines between secondary structures were generated. When a segment of the protein containing the polyglycine loop unfolds, the change in contour length increases accordingly. This method complements hydrogen-deuterium exchange mass spectrometry, which was used to propose that proteins fold along a well-defined pathway of intermediates, deemed the foldon model. With optical tweezers, intermediates and folding trajectories can be observed in real time. Through these experiments, the folding pathway of the synthetic beta barrel and its foldons were determined. To confirm these results, additional protein variants where the pulling handles are placed between secondary structures rather than at both termini were tested, coined “off-axis” pulling.
Message To Sponsor
I am Ethan, a rising junior studying Chemical Biology. I would like to thank you for this opportunity allowing me to pursue biophysics research in the Bustamante group this summer. I am eager to contribute to the field of transcription factors, which has broad implications in molecular biology and medicine.