This special Physics department colloquium is scheduled for Monday 11\/23\/15 at 3:30 PM in the Kenwood Interdisciplinary Research Complex (KIRC) Room KEN 1150. Coffee and cookies will be available in KEN 3118 (third floor kitchenette located next to the elevators) at 3:00 PM. Anyone is welcome.<\/p>\n
Time-Resolved, Near Atomic Resolution Structural Studies at the Free Electron Laser<\/strong> Time-resolved serial femtosecond crystallography (TR-SFX) employs X-Ray free electron lasers (XFELs) to provide X-ray pulses of femtosecond (fs) duration with 1012 photons per pulse. For structure determination, protein crystals on the micrometer length scale (microcrystals) are injected into the X-ray beam and the resulting diffraction patterns are recorded on fast-readout pixel detectors. Although these intense pulses deposit enough energy to ultimately destroy the protein, the processes that lead to diffraction occur before the crystal is destroyed. This diffraction-before-destruction principle overcomes radiation damage since each diffraction image is obtained from a fresh crystal. Therefore, reversible and non-reversible reactions may be studied in the same fashion. <\/p>\n With an initial experiment performed at the Linac Coherent Light Source (LCLS) we demonstrated for the first time that near atomic resolution TR-SFX is possible using an XFEL. Continuing on this work, we have now determined previously uncharacterized structures of the photoactive yellow protein photocycle. This fs time-resolved study demonstrates the full capability and vision of XFELs with respect to photoactive proteins. In addition to studying photo-initiated reactions, XFELs offer the unique opportunity to explore irreversible enzymatic reactions by the mix-and-inject technique. In this method, microcrystals are mixed with a substrate and the following reaction is probed by the fs X-ray pulses in a time-resolved fashion. One of the primary missions of an XFEL is to routinely record a complete time-series at atomic resolution and near physiological temperature of these non-reversible fast enzymatic reactions. This capability would catalyze the rapid advancement of structure-based drug designs. <\/p>\n","protected":false},"excerpt":{"rendered":" This special Physics department colloquium is scheduled for Monday 11\/23\/15 at 3:30 PM in the Kenwood Interdisciplinary Research Complex (KIRC) Room KEN 1150. Coffee and cookies will be available in KEN 3118 (third floor kitchenette located next to the elevators) …<\/p>\n","protected":false},"author":63,"featured_media":0,"template":"","meta":{"_acf_changed":false,"_tribe_events_status":"","_tribe_events_status_reason":"","_tribe_events_is_hybrid":"","_tribe_events_is_virtual":"","_tribe_events_virtual_video_source":"","_tribe_events_virtual_embed_video":"","_tribe_events_virtual_linked_button_text":"","_tribe_events_virtual_linked_button":"","_tribe_events_virtual_show_embed_at":"","_tribe_events_virtual_show_embed_to":[],"_tribe_events_virtual_show_on_event":"","_tribe_events_virtual_show_on_views":"","_tribe_events_virtual_url":"","footnotes":"","uwm_wg_additional_authors":[]},"tags":[],"tribe_events_cat":[58],"class_list":["post-3015","tribe_events","type-tribe_events","status-publish","hentry","tribe_events_cat-physics-colloquia","cat_physics-colloquia"],"yoast_head":"\n
\nJason Tenboer<\/strong>, PhD Candidate\/UWM Dept. of Physics<\/p>\n