Crystal clear

The British synchrotron radiation source (SRS) at Daresbury, Cheshire was a pioneering achievement when it started work in 1981. It was the first accelerator ring to be built for the main purpose of harvesting the highly focused synchrotron radiation from electrons travelling round in circles at extremely high speeds. It became an invaluable facility for high-resolution X-ray crystallography and many other types of research. It was the first of the ‘second generation’ synchrotron facilities, soon to be followed by similar facilities in France, Japan, and the US. However, as technology progressed, ‘third generation’ synchrotrons were developed with features that optimized A new synchrotron radiation source near Oxford is exciting structural biologists. Michael Gross reports. Crystal clear the brightness of the radiation, e.g. the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. The most powerful synchrotron of the new (third) generation is the Japanese SPring-8, jointly managed by the Japan Synchrotron Radiation Research Institute and RIKEN Harima Institute. The UK is now rejoining the front line of synchrotrons with the Diamond Light Source, a third generation synchrotron and the UK’s largest investment in science for three decades. The UK government and the Wellcome Trust are jointly footing the bill. Diamond aims at becoming “the best medium-energy X-ray source in the world”. It will be 10,000 times brighter than the old synchrotron at Daresbury, due to be decommissioned in two years time. With its 562 meters circumference, and electrons picking up an energy of 3 GeV (Giga electron Volt), the scale of the facility remains one notch below the Japanese instrument, which reaches 8 GeV on a 1436 m circumference and already has 48 beamlines in operation. Diamond will operate only seven beamlines from January onwards, but is set to increase this number steadily, by four or five each year. The beamlines feed into socalled hutches where optical and other experimental equipment is set up for specific types of research, e.g. materials science, or X-ray crystallography of proteins. As is the practice with other synchrotrons, scientists both from academia and from industry will be able to book time slots on one of the beamlines, provided their proposals are approved by peer review. Projects that are likely to benefit from the facility range from the structural biology of proteins, protein complexes and viruses through to the investigation of chocolate. Louise Johnson, Director of Life Sciences at Diamond Light Source and Head of Molecular