Journal of Synchrotron Radiation (Nov 2024)

VMXm – A sub-micron focus macromolecular crystallography beamline at Diamond Light Source

  • Anna J. Warren,
  • Jose Trincao,
  • Adam D. Crawshaw,
  • Emma V. Beale,
  • Graham Duller,
  • Andrew Stallwood,
  • Mark Lunnon,
  • Richard Littlewood,
  • Adam Prescott,
  • Andrew Foster,
  • Neil Smith,
  • Guenther Rehm,
  • Sandira Gayadeen,
  • Christopher Bloomer,
  • Lucia Alianelli,
  • David Laundy,
  • John Sutter,
  • Leo Cahill,
  • Gwyndaf Evans

DOI
https://doi.org/10.1107/S1600577524009160
Journal volume & issue
Vol. 31, no. 6
pp. 1593 – 1608

Abstract

Read online

VMXm joins the suite of operational macromolecular crystallography beamlines at Diamond Light Source. It has been designed to optimize rotation data collections from protein crystals less than 10 µm and down to below 1 µm in size. The beamline has a fully focused beam of 0.3 × 2.3 µm (vertical × horizontal) with a tuneable energy range (6–28 keV) and high flux (1.6 × 1012 photons s−1 at 12.5 keV). The crystals are housed within a vacuum chamber to minimize background scatter from air. Crystals are plunge-cooled on cryo-electron microscopy grids, allowing much of the liquid surrounding the crystals to be removed. These factors improve the signal-to-noise during data collection and the lifetime of the microcrystals can be prolonged by exploiting photoelectron escape. A novel in vacuo sample environment has been designed which also houses a scanning electron microscope to aid with sample visualization. This combination of features at VMXm allows measurements at the physical limits of X-ray crystallography on biomacromolecules to be explored and exploited.

Keywords