Segmented flow generator for serial crystallography at the European X-ray free electron laser

• Serial femtosecond crystallography (SFX) with X-ray free electron lasers (XFELs) allows structure determination of membrane proteins and time-resolved crystallography. Common liquid sample delivery continuously jets the protein crystal suspension into the path of the XFEL, wasting a vast amount of sample due to the pulsed nature of all current XFEL sources. The European XFEL (EuXFEL) delivers femtosecond (fs) X-ray pulses in trains spaced 100 ms apart whereas pulses within trains are currently separated by 889 ns. Therefore, continuous sample delivery via fast jets wastes >99% of sample. Here, we introduce a microfluidic device delivering crystal laden droplets segmented with an immiscible oil reducing sample waste and demonstrate droplet injection at the EuXFEL compatible with high pressure liquid delivery of an SFX experiment. While achieving ~60% reduction in sample waste, we determine the structure of the enzyme 3-deoxy-D-manno-octulosonate-8-phosphate synthase from microcrystals delivered in droplets revealing distinct structural features not previously reported. 

Subject headings

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

Keyword

crystallography

droplet

enzyme activity

high pressure

laser method

segmentation

water treatment

aqueous solution

Article

conformational transition

controlled study

crystal structure

high performance liquid chromatography

physical parameters

pulse rate

synchrotron radiation

three dimensional printing

X ray crystallography

devices

electron

hydrodynamics

lab on a chip

laser

ultrastructure

2-dehydro-3-deoxyphosphooctonate aldolase

Escherichia coli protein

lyase

Aldehyde-Lyases

Electrons

Escherichia coli Proteins

Lab-On-A-Chip Devices

Lasers

Publication and Content Type

ref (subject category)

art (subject category)