Biology with free-electron X-ray lasers

Special edition of Philosophical Transactions B describes an emerging field


Cover © Royal Society.

The invention of X-ray free-electron lasers (XFEL) has unveiled new vistas into the world of molecules and atoms. This is of particular interest to biologists, striving to understand the workings of the molecular machinery within the organism. A special issue of the scientific journal Philosophical Transactions B, dedicated to "biology with free-electron X-ray lasers", now collects a remarkable set of articles that showcase, on a scientific level, the very recent innovations and results that are driving this new field, including several high profile results from the Center for Free-Electron Laser Science CFEL at DESY. CFEL is a cooperation of DESY, the University of Hamburg and the Max Planck Society.

"It is often said that 'to see something new, you must do something new', and the invention of the X-ray free-electron laser is a fine example of how a technological breakthrough can give scientists new eyes", write Prof. John Spence from the Arizona State University and DESY scientist Prof. Henry Chapman from CFEL in their introduction to the special issue, published on 9 June by the British Royal Society. Chapman, who is also a professor at the University of Hamburg, and Spence have compiled and edited the special issue of the journal, following a four-day high profile meeting on the topic they organised last autumn.

X-ray free-electron lasers like the European XFEL that is currently being built from the DESY campus to the neighbouring town of Schnefeld employ powerful particle accelerators to produce ultra-short and super-bright flashes of X-ray light, complementing well-established X-ray research light sources like synchrotrons. For instance, thanks to the intense XFEL pulses, scientists can use very tiny crystals of proteins to elucidate the structure of these biomolecules. As many biomolecules are notoriously hard to crystallise, this opens up new possibilities to investigate proteins that were difficult to study before. With XFELs it may even become possible one day to study individual molecules without crystallising them at all. Also, XFELs can investigate biomolecules at room temperature, avoiding the deep-freezing often used in conventional investigations. And the ultra-short XFEL flashes promise to freeze-frame molecular dynamics, making molecular movies a possibility.

There currently are three free-electron lasers for hard and soft X-ray light in operation: the Linac Coherent Light Source LCLS at the US National Accelerator Laboratory SLAC, SACLA at the Japanese research centre Riken and the Free-Electron Laser in Hamburg FLASH at DESY, the pioneer of high-energy free-electron lasers. "The scientific papers in the special issue, some of which are available as open access, provide a very complete survey of the state of the art of biological research using XFELs and will serve as a valuable guide for this growing field," emphasises Chapman. "As we write in our introduction, the birth of a new field is the most exciting time to be involved in research."

(from DESY news)


Original publication

"Biology with free-electron X-ray lasers"; Philosophical Transactions B, Vol. 369, No. 1647, 2014; compiled and edited by John Spence and Henry Chapman;

Further Information
2013 meeting on X-ray lasers in biology: