Synchrotron Small-Angle X-Ray Scattering on Biological Macromolecules in Solution

The beamline BL19U2 is located in the Shanghai Synchrotron Radiation Facility (SSRF) and is its first beamline dedicated to biological material small-angle X-ray scattering (BioSAXS). The electrons come from an undulator which can provide high brilliance for the BL19U2 end stations. A double flat silicon crystal (111) monochromator is used in BL19U2, with a tunable monochromatic photon energy ranging from 7 to 15 keV. To meet the rapidly growing demands of crystallographers, biochemists and structural biologists, the BioSAXS beamline allows manual and automatic sample loading/unloading. A Pilatus 1M detector (Dectris) is employed for data collection, characterized by a high dynamic range and a short readout time. The highly automated data processing pipeline SASFLOW was integrated into BL19U2, with help from the BioSAXS group of the European Molecular Biology Laboratory (EMBL, Hamburg), which provides a user-friendly interface for data processing. The BL19U2 beamline was officially opened to users in March 2015. To date, feedback from users has been positive and the number of experimental proposals at BL19U2 is increasing. A description of the new BioSAXS beamline and the setup characteristics is given, together with examples of data obtained.

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Conservative interpretation of small-angle X-ray scattering data from biological macromolecules

10.14264/uql.2017.758 ◽

2017 ◽

Author(s):

Lachlan Casey

Keyword(s):

Small Angle ◽

Scattering Data ◽

Biological Macromolecules ◽

X Ray ◽

X Ray Scattering ◽

Ray Scattering

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Quality control of protein standards for molecular mass determinations by small-angle X-ray scattering

Journal of Applied Crystallography ◽

10.1107/s002188981000138x ◽

2010 ◽

Vol 43 (2) ◽

pp. 237-243 ◽

Cited By ~ 19

Author(s):

Shuji Akiyama

Keyword(s):

Quality Control ◽

Molecular Mass ◽

Small Angle ◽

Biological Macromolecules ◽

Average Deviation ◽

Saxs Data ◽

X Ray ◽

X Ray Scattering ◽

Standard Quality ◽

Ray Scattering

Small-angle X-ray scattering (SAXS) is a powerful technique with which to evaluate the size and shape of biological macromolecules in solution. Forward scattering intensity normalized relative to the particle concentration,I(0)/c, is useful as a good measure of molecular mass. A general method for deducing the molecular mass from SAXS data is to determine the ratio ofI(0)/cof a target protein to that of a standard protein with known molecular mass. The accuracy of this interprotein calibration is affected considerably by the monodispersity of the prepared standard, as well as by the precision in estimating its concentration. In the present study, chromatographic fractionation followed by hydrodynamic characterization is proposed as an effective procedure by which to prepare a series of monodispersed protein standards. The estimation of molecular mass within an average deviation of 8% is demonstrated using monodispersed bovine serum albumin as a standard. The present results demonstrate the importance of protein standard quality control in order to take full advantage of interprotein calibration.

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Recent developments in small-angle X-ray scattering and hybrid method approaches for biomacromolecular solutions

Emerging Topics in Life Sciences ◽

10.1042/etls20170138 ◽

2018 ◽

Vol 2 (1) ◽

pp. 69-79 ◽

Cited By ~ 10

Author(s):

Martin A. Schroer ◽

Dmitri I. Svergun

Keyword(s):

Small Angle ◽

Scattering Data ◽

Quality Data ◽

Biological Macromolecules ◽

Ambient Conditions ◽

X Ray ◽

X Ray Scattering ◽

Analysis Methods ◽

Recent Developments ◽

Ray Scattering

Small-angle X-ray scattering (SAXS) has become a streamline method to characterize biological macromolecules, from small peptides to supramolecular complexes, in near-native solutions. Modern SAXS requires limited amounts of purified material, without the need for labelling, crystallization, or freezing. Dedicated beamlines at modern synchrotron sources yield high-quality data within or below several milliseconds of exposure time and are highly automated, allowing for rapid structural screening under different solutions and ambient conditions but also for time-resolved studies of biological processes. The advanced data analysis methods allow one to meaningfully interpret the scattering data from monodisperse systems, from transient complexes as well as flexible and heterogeneous systems in terms of structural models. Especially powerful are hybrid approaches utilizing SAXS with high-resolution structural techniques, but also with biochemical, biophysical, and computational methods. Here, we review the recent developments in the experimental SAXS practice and in analysis methods with a specific focus on the joint use of SAXS with complementary methods.

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