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Abstract: The Diamond Light Source, a third generation synchrotron in the UK, is now operational and has had its first users collecting data. We report here a progress update. Diamond is well set up to cater for the macromolecular crystallography (MX) community. There are three beamlines specifically for MX out of seven phase-one beamlines with several other MX beamlines planned for later phases of construction. The three beamlines are essentially designed to be the same although one beamline is set up such that pathogenic samples can be analysed safely. Automation played a strong role in the design criteria so all beamlines are equipped with Rigaku Actor sample-handling robots. Each beamline uses an ADSC Quantum 315R CCD detector, mounted on an A-frame assembly. An on-line viewing system allows users to see their samples as the X-rays will hit them. Each of the three beamlines will be tunable in the range 0.5 to 2.5Å, radiation being provided by in-vacuum undulators allowing MAD and SAD experiments to be carried out with ease. Each experimental beamline has its own 20 TB data storage to cope with the huge amount of data we expect to be produced. Control software has been developed to facilitate data collection and gives users a simple interface with which to carry out their experiments. Work is about to begin on the construction of the first side-station which will be a fixed-wavelength experimental station aimed at the high-throughput users who do not require tunable X-rays. The micro-focus beamline hutches have now been built and installation of services will begin shortly. 2007 will be an exciting time for MX work at Diamond with commissioning coming to an end and users beginning to use the facility routinely.

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Abstract: Diamond Light Source [1] is the new UK third generation synchrotron located south of Oxford. In January 2007 Diamond welcomed first users. In Phase 1 seven beamlines are funded which includes three beamlines for macromolecular crystallography (MX) [2]. These are currently in a commissioning phase aimed for optimisation of operation. The beamlines are similar in design and take radiation from an in-vacuum undulator. A double crystal monochromator and a Kirkpatrick-Baez mirror arrangement are the main optical components. First experience from operation and results of the commissioning of the MX beamlines will be presented. This will include discussion of the beam properties, status and performance of the optical components and diagnostics in the optics hutch as well as results from commissioning of the equipment in the 1 experimental end station. The software environment and results from data collections will also be discussed. [1] http://www.diamond.ac.uk [2] http://www.diamond.ac.uk/MX

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Abstract: Three beamlines dedicated to macromolecular crystallography, I02, I03 and I04 at Diamond Light Source are presented. These beamlines formed the life science component of Phase 1 of Diamond Light Source. The article provides details of the design and the current status of the beamlines

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Abstract: Diamond Light Source [1] is the UK third generation synchrotron facility located south of Oxford. In the first Phase the structural biology community was served by the macromolecular crystallography (MX) beamlines I02, I03 and I04 starting with the user programme in early 2007. These widely tuneable (5-25 keV) SAD/MAD beamlines were complemented in Phase 2 with a MAD capable microfocus beamline I24 (7-25 keV) and a fixed-wavelength high-throughput station I04-1 (13.53 keV). In Phase 3 the long wavelength beamline I23 (3-12 keV), which is in the planning and construction stage, will complement the MX beamline portfolio [2]. In order to adapt to the future scientific requirements of the structural biology community and to increase efficiency, various areas of the beamlines are being improved and new techniques explored. The automation system is constantly being improved, including a quicker sample exchange with the sample transfer robot and automatic loop finding and centering procedures. All beamlines can now also be fully operated remotely. Three beamlines (I03, I04-1, I24) are now equipped with fast Pilatus detectors and it is planned to provide the other beamlines with fast detector systems as well. This leads to an increase in efficiency and throughput and allows for new methods like faster grid scans for locating hardly visible samples or to find the best area of a larger sample. Data collection strategies and crystal and diffraction image characterization are provided automatically. Very shortly after the data collection has finished the results from our automatic data processing pipeline are available and this extends now to the generation of difference electron density maps if a suitable PDB file is provided. More recently, an upgrade programme for the experimental end-stations of the Phase 1 MX beamlines (I02, I03, I04) has been initiated and is nearing completion. The completely new design allows for an easier change between experiments at cryo or room temperature or a humidity controlled setup. In-situ screening of crystallization plates is also actively being developed on all beamlines. Beam delivery to the Phase 1 beamlines will be with a refurbished bimorph KB mirror system providing typical beam sizes of 80 μm x 20 μm over the complete energy range. Furthermore, the new end-station is also equipped with two sets of compound refractive lenses (CRL) providing a beam size of 8 x 2 microns, thus enabling microfocus and standard beam size work easily on the same beamline. The implementation of a mini kappa goniometer head is being developed which will allow for more sophisticated data collection strategies. Some new developments and preliminary results will be discussed. Use of the Diamond MX beamlines has resulted in the deposition of 731 structures to the PDB so far and productivity has increased since the start of operation.

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Abstract: The hydration state of macromolecular crystals often affects their overall order and, ultimately, the quality of the X-ray diffraction pattern that they produce. Post-crystallization techniques that alter the solvent content of a crystal may induce rearrangement within the three-dimensional array making up the crystal, possibly resulting in more ordered packing. The hydration state of a crystal can be manipulated by exposing it to a stream of air at controlled relative humidity in which the crystal can equilibrate. This approach provides a way of exploring crystal hydration space to assess the diffraction capabilities of existing crystals. A key requirement of these experiments is to expose the crystal directly to the dehydrating environment by having the minimum amount of residual mother liquor around it. This is usually achieved by placing the crystal on a flat porous support (Kapton mesh) and removing excess liquid by wicking. Here, an alternative approach is considered whereby crystals are harvested using adhesives that capture naked crystals directly from their crystallization drop, reducing the process to a one-step procedure. The impact of using adhesives to ease the harvesting of different types of crystals is presented together with their contribution to background scattering and their usefulness in dehydration experiments. It is concluded that adhesive supports represent a valuable tool for mounting macromolecular crystals to be used in humidity-controlled experiments and to improve signal-to-noise ratios in diffraction experiments, and how they can protect crystals from modifications in the sample environment is discussed.