Advances in mass spectrometry instrumentation and experimental design have led to significant inroads in the characterization of biological molecules like proteins and lipids, thus translating to new applications in the field of proteomics, lipidomics and structural biology. Ultraviolet photodissociation (UVPD) is a fast, higher energy ion activation mode that results in extensive and information fragmentation of molecules, and ion activation/dissociation can be accomplished using a single 5 ns laser pulse. UVPD offers a frontier MS/MS technology for characterization of intact proteins, including mapping post-translational modifications and ligand binding sites. There has been growing interest in employing MS/MS strategies to examine native protein structures by disassembling the complexes and sequencing the constituent proteins in the gas phase. In the context of protein-ligand complexes, the relative abundances of fragment ions generated by UVPD correlate with variations in the intramolecular and intermolecular interactions that stabilize particular regions of the proteins. Upon UVPD, products retaining non-covalently bound ligands are also formed and afford binding site information. For multimeric protein complexes, UVPD disassembles the complexes to reflect sub-unit architecture as well as generating sequence ions that identify the proteins. UVPD has also proven useful for elucidation of key structural details of lipids, like localization of double bond positions. This seminar will showcase the capabilities of UVPD for characterization of biological molecules and cover new strategies to improve the performance of UVPD.
Dr. Jennifer S. Brodbelt is the Rowland Pettit Centennial Professor of Chemistry at the University of Texas at Austin and is also serving as Chairperson. She earned her B.S. degree in chemistry at the University of Virginia and her doctorate in chemistry at Purdue University under the supervision of Prof. Graham Cooks. After a post-doctoral position at the University of California at Santa Barbara with Prof. Mike Bowers, she began her academic career at the University of Texas. Her research interests focus on the development and application of photodissociation mass spectrometry for characterization of the structures and modifications of biological molecules, including peptides, proteins, nucleic acids, oligosaccharides, and lipids. She served as the Director of Graduate Education in the Department of Chemistry for over 20 years and recently became Chairperson in 2019. She serves as an Associate Editor for the Journal of the American Society for Mass Spectrometry, and she served as President of the American Society for Mass Spectrometry from 2014-2016.