Harnessing the power of an X-ray laser for serial crystallography of membrane proteins crystallized in lipidic cubic phase. IUCrJ 2020 Nov 01;7(Pt 6):976-984
Date
11/20/2020Pubmed ID
33209312Pubmed Central ID
PMC7642783DOI
10.1107/S2052252520012701Scopus ID
2-s2.0-85095813668 (requires institutional sign-in at Scopus site) 12 CitationsAbstract
Serial femtosecond crystallography (SFX) with X-ray free-electron lasers (XFELs) has proven highly successful for structure determination of challenging membrane proteins crystallized in lipidic cubic phase; however, like most techniques, it has limitations. Here we attempt to address some of these limitations related to the use of a vacuum chamber and the need for attenuation of the XFEL beam, in order to further improve the efficiency of this method. Using an optimized SFX experimental setup in a helium atmosphere, the room-temperature structure of the adenosine A2A receptor (A2AAR) at 2.0 Å resolution is determined and compared with previous A2AAR structures determined in vacuum and/or at cryogenic temperatures. Specifically, the capability of utilizing high XFEL beam transmissions is demonstrated, in conjunction with a high dynamic range detector, to collect high-resolution SFX data while reducing crystalline material consumption and shortening the collection time required for a complete dataset. The experimental setup presented herein can be applied to future SFX applications for protein nanocrystal samples to aid in structure-based discovery efforts of therapeutic targets that are difficult to crystallize.
