Jörg Standfuss (homepage) is going to visit CLiC on a two day trip on Thursday, October, 17th and Friday, October 18th.
He will give a talk on Thursday, October, 17th in Seminar room N100, 1.14 starting 17.00 o´clock on
"How we use the Swiss Free Electron Laser to resolve the structural dynamics of light-sensitive proteins"
Abstract:
X-ray free electron lasers offer exciting new opportunities to study the structural dynamics of light-sensitive proteins by time-resolved serial crystallography. It is now possible to determine whole series of structural snapshots at high spatial resolution and at precise time delays after activation to assemble them into flipbook-like movies of proteins in action.
Based on our studies of the light-driven proton pump bacteriorhodopsin (bR), I will outline the possibilities but also the challenges that have to be overcome before we can routinely study atomic rearrangements in proteins at ambient temperature and in real time. One of the current bottlenecks is that access to X-ray lasers will remain scarce for the foreseeable future. To allow experiments at synchrotron sources, we have adapted high viscosity injector systems to carry out routine room-temperature serial millisecond crystallography at the Swiss Light Source (SLS) (1, 2). First pilot experiments at the Swiss Free Electron Laser (SwissFEL) highlight the importance of careful sample preparation to make the most of the new femtosecond X-ray laser sources.
Molecular movies of structural changes prepared from 42 structural snapshots ranging from the femtosecond to the millisecond regime allowed us to study energy capture and proton transfer steps in bR with astounding detail (2-4). The sequential rearrangements throughout the bR photocycle follow the basic predictions of an alternate access model and provide a template to understand the principal transport steps in other membrane pumps. In the remaining time, I will describe our progress in using SwissFEL to resolve the structural dynamics of a light-driven cation pump, a visual G protein-coupled receptor and how synthetic photoswitches influence their protein targets.