Event interval: Single day event
Campus location: Bagley Hall (BAG)
Online Meeting Link: https://youtube.com/live/YdeM_SCtjYY?feature=share
Accessibility Contact: chem59x@uw.edu
Event Types: Lectures/Seminars
Event sponsors:
This lecture is supported by the Paul C. Cross Endowed Fund, dedicated to the memory of Professor Paul C. Cross by his family and many friends and colleagues in 2002. Prof. Cross was a distinguished physical chemist who led the effort to elevate the UW Department of Chemistry to national prominence when he served as professor and chair from 1949 to 1961. Prof. Cross promoted departmental growth through the expansion of the graduate program, his emphasis on the acquisition and construction of revolutionary new instrumentation, and his encouragement of faculty to secure external federal funding to expand their research programs.
Link: https://hanlab.northwestern.edu/
The Shape of Water on Active Surfaces
Professor Songi Han – Department of Chemistry, Northwestern University
Host: Stefan Stoll
The ability to “turn the lights on” to directly see the molecular machinery of life fundamentally changes how we understand and manipulate biology. One such material that is so fundamental to how the molecular machinery of life operates, in what way molecules interact, associate, assemble and perform chemical and biological processes, but is exceptionally difficult to characterize is water. Water has properties of a molecule and a material, it is a liquid with fluid properties, but it also has structure, and in fact adopts multiple structures in solutions containing your favorite protein. After all, is there such thing as structured water in liquid water? Of course there is! I will briefly go over 3-4 key nuclear magnetic resonance and electron-nuclear double resonance spectroscopy tools of 1H and 17O to identify the dynamical, structural, and thermodynamical property of water that varies with the surface chemistry and topology of the dissolved small molecules or biological macromolecules. Some of them are old tricks but re-invented, some are new tricks, and some are well known tools. I will start by discussing why it matters if shaping of water occurs and under what conditions. Think about what criteria do molecules have to fulfill to be a “prion”, the protein assembly state that adopts a misfolded protein shape and can recruit naïve proteins to be infected and assimilated to take on the same misfolded shape and perpetuate this pattern in ways that wreaks havoc in the infected person. Figuring this out might be at the crux of finding at least a diagnostic tool or, even better, a therapeutic strategy for Alzheimer’s disease and other tauopathies. Next, imagine the perfect antifreeze molecule or material. What do you think such an agent has to accomplish to prevent ice from growing and propagating? When asked without being an expert in protein aggregation or antifreeze molecules, I would not be surprised if you landed at the same answer and hypotheses as we did. Yet, the two hypotheses that I will present that guide our ongoing studies for these two questions are opposite to many existing design criteria or considered “unusual” ideas that not many people think are relevant to solving the problem. The solution to this dilemma is that we simply must go all the way to demonstrating the viability of our hypotheses and potentially making first steps towards finding solutions to generating disease-specific aggregate strain (currently rarely accomplished, at least not rationally) or antifreeze agents (which is so complex that experts explain that this is “black art”). After clarifying why the shape of water is a practically necessary concept, I will briefly discuss the principles behind the measurements, and why it was not done routinely before. I will also share that some of the control experiments we did with DMSO, glycerol or phosphate anions are equally fascinating as the complex systems and show that these “simple” mixtures that are not so simple. Finally, I could not be giving a talk on structured water at the University of Washington without mentioning “Exclusion Zone (EZ) Water”. Despite having spent many years studying water, I have only recently come to learn about this concept. I will connect the dots to my research and share how I intend to use the conditions of generating EZ Water to enhance the molecular effect of water in modulating biomolecular function.