Solution scattering at the Life Science X-ray Scattering (LiX) beamline

This work reports the instrumentation and software implementation at the Life Science X-ray Scattering (LiX) beamline at NSLS-II in support of biomolecular solution scattering. For automated static measurements, samples are stored in PCR tubes and grouped in 18-position sample holders. Unattended operations are enabled using a six-axis robot that exchanges sample holders between a storage box and a sample handler, transporting samples from the PCR tubes to the X-ray beam for scattering measurements. The storage box has a capacity of 20 sample holders. At full capacity, the measurements on all samples last for ∼9 h. For in-line size-exclusion chromatography, the beamline-control software coordinates with a commercial high-performance liquid chromatography (HPLC) system to measure multiple samples in batch mode. The beamline can switch between static and HPLC measurements instantaneously. In all measurements, the scattering data span a wide q-range of typically 0.006–3.2 Å−1. Functionalities in the Python package py4xs have been developed to support automated data processing, including azimuthal averaging, merging data from multiple detectors, buffer scattering subtraction, data storage in HDF5 format and exporting the final data in a three-column text format that is acceptable by most data analysis tools. These functionalities have been integrated into graphical user interfaces that run in Jupyter notebooks, with hooks for external data analysis software.

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Global Small-Angle X-ray Scattering Data Analysis of Triacylglycerols in the Molten State (Part I)

The Journal of Physical Chemistry B ◽

10.1021/acs.jpcb.8b06704 ◽

2018 ◽

Vol 122 (45) ◽

pp. 10320-10329 ◽

Cited By ~ 7

Author(s):

Amin Sadeghpour ◽

Marjorie Ladd Parada ◽

Josélio Vieira ◽

Megan Povey ◽

Michael Rappolt

Keyword(s):

Data Analysis ◽

Small Angle ◽

Scattering Data ◽

Molten State ◽

X Ray ◽

X Ray Scattering ◽

Ray Scattering

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Size-exclusion chromatography small-angle X-ray scattering of water soluble proteins on a laboratory instrument

Journal of Applied Crystallography ◽

10.1107/s1600576718014462 ◽

2018 ◽

Vol 51 (6) ◽

pp. 1623-1632 ◽

Cited By ~ 8

Author(s):

Saskia Bucciarelli ◽

Søren Roi Midtgaard ◽

Martin Nors Pedersen ◽

Søren Skou ◽

Lise Arleth ◽

...

Keyword(s):

Size Exclusion Chromatography ◽

Small Angle ◽

Size Exclusion ◽

Scattering Data ◽

X Ray ◽

Laboratory Instrument ◽

X Ray Scattering ◽

Home Institution ◽

Exclusion Chromatography ◽

Ray Scattering

Coupling of size-exclusion chromatography with biological solution small-angle X-ray scattering (SEC-SAXS) on dedicated synchrotron beamlines enables structural analysis of challenging samples such as labile proteins and low-affinity complexes. For this reason, the approach has gained increased popularity during the past decade. Transportation of perishable samples to synchrotrons might, however, compromise the experiments, and the limited availability of synchrotron beamtime renders iterative sample optimization tedious and lengthy. Here, the successful setup of laboratory-based SEC-SAXS is described in a proof-of-concept study. It is demonstrated that sufficient quality data can be obtained on a laboratory instrument with small sample consumption, comparable to typical synchrotron SEC-SAXS demands. UV/vis measurements directly on the SAXS exposure cell ensure accurate concentration determination, crucial for direct molecular weight determination from the scattering data. The absence of radiation damage implies that the sample can be fractionated and subjected to complementary analysis available at the home institution after SEC-SAXS. Laboratory-based SEC-SAXS opens the field for analysis of biological samples at the home institution, thus increasing productivity of biostructural research. It may further ensure that synchrotron beamtime is used primarily for the most suitable and optimized samples.

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