Speed and power of X-ray laser helps unlock molecular mysteries

An international research team at the SLAC National Accelerator Laboratory has created 3D images of fragile but biologically important molecules inside protein nanocrystals. Using the Linac Coherence Light Source, a powerful X-ray laser, scientists fired femtosecond (one quadrillionth of a second) bursts of light at a stream of tumbling molecules, obliterating them as they pass. According to John C.H. Spence of Arizona State University, these laser pulses are so brief that one can outrun the radiation's damaging effects. Using the “diffract-then-destroy” approach, the research team recorded about a hundred scattering patterns per second from protein nanocrystals. An overview and early results of this new imaging technique will be presented at the 2012 meeting of the American Crystallographic Association.