Episode 62: When One Atom Changes Everything | JC Poutsma on Mass Spectrometry, Proteomics & Gas-Phase Chemistry

What happens when you replace just one atom in an amino acid?In this episode of  @ChromatographyTalk  David sits down with JC Poutsma, Professor of Chemistry at William & Mary, to explore the fascinating world of gas-phase ion chemistry, peptide fragmentation, and the hidden molecular behavior revealed by mass spectrometry.Professor Poutsma explains how subtle structural changes in biomolecules can dramatically alter protein folding, fragmentation pathways, and biological activity. The conversation dives into unusual amino acids like canavanine, the “proline effect” in peptide fragmentation, ion mobility spectrometry, IR spectroscopy, and why understanding the fundamentals of chemistry still matters in modern analytical science.Whether you work in LC-MS, proteomics, physical chemistry, or analytical instrumentation—or you simply enjoy learning how molecules behave at the most fundamental level—this episode offers a fascinating look at the chemistry happening behind the spectra.Topics Discussed* What is gas-phase ion chemistry?* How mass spectrometers can function as reaction vessels* Why unusual amino acids matter* The chemistry of canavanine vs arginine* How one atom substitution changes protein behavior* Peptide fragmentation mechanisms in proteomics* The “proline effect” in tandem MS* Ion mobility spectrometry explained* IR spectroscopy for structural characterization* Why understanding analytical fundamentals still matters* Teaching chemistry in the age of AI and automation About the GuestJC Poutsma is a Professor of Chemistry at William & Mary whose research focuses on gas-phase ion chemistry, biomolecular structure, peptide fragmentation, spectroscopy, and the physical chemistry underlying mass spectrometry.#MassSpectrometry #Proteomics #AnalyticalChemistry #LCMS #MassSpec #Chemistry #IonMobility #Spectroscopy #PeptideFragmentation #PhysicalChemistry #ASMS #Chromatography