Invited Paper SA+AS+BI+MI-TuA7
Sample Delivery Methods for X-ray Free Electron Lasers

Tuesday, November 8, 2016, 4:20 pm, Room 103C

Serial crystallography at XFEL’s has shown great promise in recent years for solving crystal structures of proteins, which produce only micron sized crystals. Liquid jets have been very successful for delivery of microcrystals to the X-ray beam. The commonly used liquid injection system will be discussed. High sample consumption has motivated the development of an injector, which uses high viscosity media like Lipidic Cubic Phase (LCP). G-protein coupled receptors are an important group of membrane proteins which are often crystallized in LCP. The injector generations a microscopic stream of LCP with adjustable speed for sample delivery to the X-ray beam¹. Some important GPCR structures could be solved with this device at the LCLS². In addition, new media with similar viscosity to LCP have been developed which enable delivery of soluble or membrane proteins into the X-ray beam with low sample consumption³. The high viscosity injection method has also been shown to facilitate serial diffraction experiments with microcrystals at synchrotron microfocus beamlines. This talk will highlight these developments and discuss the possibilities.

¹ Weierstall, U., James, D., Wang, C., White, T. A., Wang, D., Liu, W., et al. (2014). Lipidic cubic phase injector facilitates membrane protein serial femtosecond crystallography. Nature Communications, 5. http://doi.org/10.1038/ncomms4309

² Kang, Y., Zhou, X. E., Gao, X., He, Y., Liu, W., Ishchenko, A., et al. (2015). Crystal structure of rhodopsin bound to arrestin by femtosecond X-ray laser. Nature, 523(7562), 561–567. http://doi.org/10.1038/nature14656

³ Conrad, C. E., Basu, S., James, D., Wang, D., Schaffer, A., Zatsepin, N. A., et al. (2015). A novel inert crystal delivery medium for serial femtosecond crystallography. IUCrJ, 2(4), 421–430.