An international collaboration has published the results of the first scientific experiments at Europe's new X-ray free electron laser XFEL carried out in September 2017 at Hamburg. The pioneering work has revealed a previously unknown structure of an enzyme responsible for antibiotics resistance, and has demonstrated that the new research facility can speed up experiments by more than an order of magnitude.The XFEL is designed to deliver X-ray flashes every 220 nanoseconds, to be compared to the 120 flashes per second of the fastest pulse rate so far.To unravel the three-dimensional structure of a biomolecule, such as an enzyme, the pulses are used to obtain flash X-ray exposures of tiny crystals grown from that biomolecule. Each exposure gives rise to a characteristic diffraction pattern on the detector. If enough such patterns are recorded from all sides of a crystal, the spatial structure of the biomolecule can be calculated.
The measurements show that it is possible to record high quality structural information, which is the first step towards recording snapshots of the biochemical reaction between enzymes and their substrates. Movies of chemical and biochemical reactions are just one example of a whole new spectrum of scientific experiments enabled by the European XFEL.
The European XFEL in the Hamburg area is a new international research facility created by the collaboration of institutions from 12 countries, including Italy and INFN. In particular, the LASA laboratory has given an important contribution for the superconducting accelerating cavities and for the stability of injected beam. It is the world’s largest X-ray laser, producing ultrashort and extremely bright flashes of X-ray radiation. The European XFEL is driven by an approximately 2 kilometers long superconducting linear particle accelerator. It accelerates electrons in tight bunches to almost the speed of light. The electron bunches are then forced through a magnetic slalom course in so-called undulators and radiate off X-rays that add up to a laser-like pulse. The European XFEL is designed to generate 27000 such pulses per second.