High-speed fixed-target serial virus crystallography

Abstract

21We have developed a method for serial X-ray crystallography at X-ray free electron lasers (XFELs), 22 which allows for full use of the current 120 Hz repetition rate of the Linear Coherent Light Source 23 (LCLS). Using a micro-patterned silicon chip in combination with the high-speed Roadrunner 24 goniometer for sample delivery we were able to determine the crystal structures of a picornavirus, 25 bovine enterovirus 2 (BEV2), and the cytoplasmic polyhedrosis virus type 18 polyhedrin. Total data 26 collection times were less than 14 and 10 minutes, respectively. Our method requires only micrograms 27 of sample and will therefore broaden the applicability of serial femtosecond crystallography to 28 challenging projects for which only limited amounts of samples are available. By synchronizing the 29 sample exchange to the XFEL repetition rate it further allows for the most efficient use of the limited 30 beamtime available at XFELs and a significant increase in sample throughput at these facilities. 31 32 Introduction 33

The hit-and-return system enables efficient time-resolved serial synchrotron crystallography

“…Serial femtosecond crystallography (SFX) re-established this technique as a large series of single-shot experiments, greatly facilitating data collection and providing access to non-reversible reactions in time-resolved experiments (TR-SFX). The problem has been that to date these studies have been restricted to the use of large crystals and conventional data collection methods limiting the scope of potential experiments due to both limited supply of sufficient quality crystals and X-ray damage considerations 16,[20][21][22] . Only very few of the TRX studies do not rely on reversible, light induced systems and radiation damage of the sample often proves to be a serious problem.…”

The slip-and-slide algorithm: a refinement protocol for detector geometry

“…However, it will be more robust for weak data where the knowledge of the predicted peak location can be used to select high value pixels that are more likely to be from a Bragg peak-diffracted X-ray. The geometry refinement described here allowed the structure solution of bovine enterovirus type 2 by using only 352 indexed diffraction patterns (Roedig et al, 2017). In that case geometry refinement revealed a 0.5 mm tilt across the detector, correction for which enabled significantly more accurate prediction of Bragg spot locations and hence more reliable intensity estimates.…”

Towards an Optimal Sample Delivery Method for Serial Crystallography at XFEL

“…Many fixed-target chip designs employ crystalline silicon [130][131][132][133][134] or silicon nitride [126,[135][136][137][138]. These materials are chosen for their low scattering background, high transmission to X-ray and great precision in microfabrication using photolithography technique.…”