Facility News: Workshop on Time-Resolved Crystallography Concludes Successfully
Home › News › Facility News › Workshop ...
- December 2008 -
Workshop Participants
BioCARS hosted a three-day workshop on time-resolved crystallography (November 20-22, 2008). The goal of the workshop was to introduce participants to the principles of time-resolved macromolecular crystallography and Laue diffraction, and to provide hands-on training in both data collection and analysis. Thirty-one participants represented 21 research groups. The international user community was represented by participants from the Czech Republic, Denmark, Canada, and Australia.
Beamline 14-ID has recently undergone a complete upgrade of both its X-ray and laser facilities, and the workshop introduced new and returning BioCARS users to these exciting new capabilities at 14-ID. The beamline now includes two new undulators that operate collinearly, a new Kirkpatrick-Baez mirror system that focuses pink beam to 90 x 30 µm2 beam size at the sample, a new picosecond laser system, and an upgraded ultra-fast X-ray chopper. As a result, 100ps time-resolved experiments can now be conducted in both hybrid and 24-bunch APS mode, with crystals 10 times smaller and X-ray exposures 10 times shorter than previously possible at BioCARS.
At the workshop, the first day was devoted to lectures and began with an overview of the principles of time-resolved crystallography by Keith Moffat (BioCARS) and an introduction to Laue diffraction method by Zhong Ren (BioCARS). New capabilities of the 14-ID beamline were introduced by Robert Henning and Tim Graber (BioCARS). These introductory lectures were followed by several lectures on methods for reaction initiation in crystals (Philip Anfinrud, NIH/NIDDK; Andy Pacheco, University of Wisconsin-Milwaukee; Andreas Möglich, The University of Chicago), mapping enzyme reactions by X-ray crystallography (Andrew Mesecar, University of Illinois at Chicago), and linking single-crystal spectroscopy to structural studies (Carrie Wilmot, University of Minnesota). The introduction to the analysis of time-resolved macromolecular x-ray data started with the last lecture of the day by Marius Schmidt, University of Wisconsin-Milwaukee, and continued on the second and third day of the workshop. The complete program and presentations in PDF format are available online at the workshop web site.
On the second and third days, participants worked in groups to collect and process Laue and time-resolved data sets, guided by Robert Henning and Vukica Srajer. Each group was allocated two hours of beam time during which they were introduced to the experimental set-up and collected Laue data using their own samples as well as photoactive yellow protein (PYP) crystals provided by BioCARS and Keith Moffat’s group (The University of Chicago). Using PYP crystals, each group collected two data sets: a dark data set and a data set at 2ms following the reaction initiation in the crystal by short laser pulses. Participants therefore had an opportunity to experience a complete time-resolved experiment in action. Given the interest of many participants in using a flow cell for time-resolved measurements, Andrew Mesecar (University of Illinois at Chicago) generously offered a demo on making and using flow cells.
Data analysis sessions ran continuously during the second and third day of the workshop. The second day started with a detailed introduction by Zhong Ren on processing of Laue data with the software package Precognition™ (Renz Research, Inc.). Throughout two days Ren worked with participants individually and as a group on particular data processing issues as they arose. On the third day, Marius Schmidt introduced participants to his program SVD4TX for singular value decomposition analysis of time-resolved crystallographic data and determination of the structural intermediates.
Based on the feedback from the workshop participants, the workshop was highly successful. Many participants left the workshop with plans for designing time-resolved experiments on their own biological systems and are looking forward to returning to BioCARS to conduct such experiments.
BioCARS and this workshop are supported by National Center for Research Resources of the National Institutes of Health (grant 5 P41 RR007707 to The University of Chicago, Keith Moffat, PI). Additional support for the workshop was provided by the Center for Advanced Radiation Sources of The University of Chicago, which operates BioCARS. The time-resolved set-up at BioCARS was funded in part through a collaboration with Philip Anfinrud (NIH/NIDDK).