BioSAXS Sample Changer: a robotic sample changer for rapid and reliable high-throughput X-ray solution scattering experiments.

Small-angle X-ray scattering (SAXS) of macromolecules in solution is in increasing demand by an ever more diverse research community, both academic and industrial. To better serve user needs, and to allow automated and high-throughput operation, a sample changer (BioSAXS Sample Changer) that is able to perform unattended measurements of up to several hundred samples per day has been developed. The Sample Changer is able to handle and expose sample volumes of down to 5 µl with a measurement/cleaning cycle of under 1 min.

Upgraded ESRF BM29 beamline for SAXS on macromolecules in solution.

Small-angle X-ray scattering (SAXS) measurements of proteins in solution are becoming increasingly popular with biochemists and structural biologists owing to the presence of dedicated high-throughput beamlines at synchrotron sources. As part of the ESRF Upgrade program a dedicated instrument for performing SAXS from biological macromolecules in solution (BioSAXS) has been installed at the renovated BM29 location. The optics hutch has been equipped with new optical components of which the two principal elements are a fixed-exit double multilayer monochromator and a 1.

Inducing phase changes in crystals of macromolecules: status and perspectives for controlled crystal dehydration.

The increase in the number of large multi-component complexes and membrane protein crystal structures determined over the last few years can be ascribed to a number of factors such as better protein expression and purification systems, the emergence of high-throughput crystallization techniques and the advent of 3rd generation synchrotron sources. However, many systems tend to produce crystals that can be extremely heterogeneous in their diffraction properties. This prevents, in many cases, the collection of diffraction data of sufficient quality to yield useful biological or phase information.

Improving diffraction by humidity control: a novel device compatible with X-ray beamlines.

Dehydration of protein crystals is rarely used, despite being a post-crystallization method that is useful for the improvement of crystal diffraction properties, as it is difficult to reproduce and monitor. A novel device for hydration control of macromolecular crystals in a standard data-collection environment has been developed. The device delivers an air stream of precise relative humidity that can be used to alter the amount of water in macromolecular crystals.