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A microfocus macromolecular crystallography beamline at the Australian Synchrotron is presented., MX2 is an in-vacuum undulator-based crystallography beamline at the 3 GeV Australian Synchrotron. The beamline delivers hard X-rays in the energy range 4.8–21 keV to a focal spot of 22 × 12 µm FWHM (H × V). At 13 keV the flux at the sample is 3.4 × 1012 photons s−1. The beamline endstation allows robotic handling of cryogenic samples via an updated SSRL SAM robot. This beamline is ideal for weakly diffracting hard-to-crystallize proteins, virus particles, protein assemblies and nucleic acids as well as smaller molecules such as inorganic catalysts and organic drug molecules. The beamline is now mature and has enjoyed a full user program for the last nine years. This paper describes the beamline status, plans for its future and some recent scientific highlights.

As-p18, an unusual fatty-acid-binding protein from a parasitic nematode, was expressed in bacteria, purified and crystallized. The use of a microfocus beamline was essential for data collection., As-p18 is a fatty-acid-binding protein from the parasitic nematode Ascaris suum. Although it exhibits sequence similarity to mammalian intracellular fatty-acid-binding proteins, it contains features that are unique to nematodes. Crystals were obtained, but initial diffraction data analysis revealed that they were composed of a number of ‘microdomains’. Interpretable data could only be collected using a microfocus beamline with a beam size of 12 × 8 µm.