BEGIN:VCALENDAR VERSION:2.0 PRODID:-//ZContent.net//ZapCalLib 1.0//EN CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VEVENT SUMMARY:Molecular recognition by proteins: The dark energy of proteins come s to light LOCATION:Chemistry A101 TZID:America/Denver DTSTART:20211007T160000 UID:2026-05-05-15-45-10@natsci.colostate.edu DTSTAMP:20260505T154510 Description:CGSO invited speaker\n\nAbout the Seminar:\n\nThe thermodynamic s of molecular recognition by proteins is a central determinant of complex biochemistry. For over a half-century\, detailed cryogenic structures hav e provided deep insight into the energetic contributions to ligand binding by proteins. We have been pursuing the elusive contributions of conformat ional entropy. The development of a dynamical proxy based on solution NMR- relaxation methods has revealed an unexpected richness in the contribution s of conformational entropy to the thermodynamics of ligand binding. The e volution of the so-called “entropy meter” from its model-dependent roo ts to its current empirically calibrated form will be presented. From this work\, it is now abundantly clear that conformational entropy is often a critical element of molecular recognition by soluble proteins. The role of solvent entropy has also been examined using a novel NMR approach based o n the favorable attributes of confinement provided by reverse micelle enca psulation. Recently\, we have approached integral membrane proteins\, whic h have eluded a similar characterization. The first examples\, pSRII and O mp W\, are found to be more dynamic in the ps-ns time regime than any prev iously characterized protein. The corresponding conformational entropy app arently stabilizes the folded state in the absence of the classic hydropho bic effect. Finally\, despite these insights\, there remains a discomforti ng disconnect between protein structure and conformational entropy. Prompt ed by the dynamical response of barnase to high pressure\, we performed an analysis of the small packing imperfections or voids surrounding over 2\, 500 methyl-bearing side chains having determined order parameters. Changes in unoccupied volume as small as a water molecule surrounding buried side chains greatly affects fast motion. The discovered relationship begins to permit construction of a united view of the relationship between changes in the internal energy\, provided by structural analysis\, and the conform ational entropy\, as represented by fast internal motion\, in the thermody namics of protein function.\n\nAbout the Speaker:\n\nProfessor Josh Wand i s Professor and Head of Biochemistry and Biophysics at Texas A&\;M Univ ersity. He also holds joint appointments in the Departments of Chemistry a nd Molecular and Cellular Medicine. Dr. Wand received his Ph.D. in biophys ics from the University of Pennsylvania in 1984. Following postdoctoral tr aining at the National Research Council of Canada in solid-state NMR\, he joined the faculty of the Institute for Cancer Research. He subsequently s pent time on the faculties of the University of Illinois at Urbana-Champai gn and the State University of New York at Buffalo. He was the Benjamin Ru sh Professor of Biochemistry &\; Biophysics at the University of Pennsy lvania for two decades before joining Texas A &\; M University in 2019. Dr. Wand teaches undergraduate biochemistry and graduate topics in biophy sics and chemistry. He has received over 25 M in research grant support ov er his career and published over 200 research and review articles and give n over 200 invited seminars and presentations at Universities and conferen ces throughout the world. He is a Fellow of the Biophysical Society and a Fellow of the American Physical Society. He continues to apply advanced so lution NMR and other techniques to questions in protein biophysics with em phasis on dynamics\, entropy and hydration in protein functions such as al lostery and a novel route to drug discovery. 4:00 pm END:VEVENT END:VCALENDAR