Time-Resolved Structural Enzymology at X-ray Free Electron Lasers

Abstract

Within the last decade, X-ray Free Electron Lasers (XFELs) have emerged across the world. These XFELs produce X-ray pulses with a duration on the order of femtoseconds, each of which contains 1012 photons. Before the XFEL, the brightest X-ray sources were 3rd generation synchrotrons. While these facilities are still very important for many experiments, XFELs allow for time-resolved experiments with femtosecond time resolution and mixing experiments that are not possible at the synchrotron. Enzymatic processes have promising prospects for medicine which use proteins as drug targets and enhance our understanding of these important biomolecules. A number of procedures are involved alongside an XFEL experiment. Before an experiment, characterization tests should be performed to confirm that the experiment will work on the beamline. Confirmation that crystals diffract can be obtained using an X-ray source either in one's own lab or at a synchrotron. Spectroscopic tests can confirm the initiation of a reaction in a sample and identify the timings of such reactions. In addition to assisting at XFEL experiments, I performed tests such as these to ensure that our group was prepared. After an experiment, the data must be processed before structures can be obtained. Due to the serial nature of XFEL experiments, a program is necessary to detect which images contain Bragg diffraction. I developed a similar program to perform the same function on serial data collected at a synchrotron.