The High Performance Macromolecular Crystallography beamline (MX3) will be capable of providing high-flux, microfocus X-rays for small and weakly diffracting protein crystals. The beamline will provide three modes of operation: goniometer, serial crystallography and in-tray screening. The beamline will be powered by a 3m in-vacuum undulator. The proposed optical system will maximise flux at the sample position and the use of a secondary source aperture will allow rapid change in beam size. The goniometer will be able to be translated out of focus to allow increase of beam size without changing the optical components. In order to produce the required high flux the beamline will also utilise a double multilayer monochromator. This will increase the bandpass (energy width) and brightness of the X-ray beam; however, this will mean that Multi-wavelength Anomalous Dispersion (MAD) experiments will not be feasible. The beamline will specialise in high flux, high speed data collection on micro crystals with a high degree of automation for crystal location and data collection.
The MX3 beamline will accept macromolecular crystal samples in several formats.
Sample shipping for robot-compatible pins will be identical to other MX beamlines at the synchrotron and remote access will be available. In-tray screening may also be provided via a mail-in system.
The core measurement capabilities of MX3 include:
- Single-pin goniometer experiments:
- “Standard” MX collection on robot mounted single crystals. Due to the high flux of MX3, an attenuated beam will be required to collect a full dataset from a single crystal, or multiple partial datasets merged from several crystals.
- In-tray screening:
- Automated in-tray screening using a tray holder on the goniometer.
- High throughput fixed target collection using silicon chip-based sample holder. Chips will be loaded offline, aligned on the beamline (separate fixed-target stages) and collected.
- Injector collection:
- Crystals introduced to the beam via a sample injector. Several designs are being considered but the production system will deliver crystals to the beam with high speed and low background scattering to allow data collection and structure solution from multiple micro-crystals.