GI-MS46-03 - EMBL Beamlines for Macromolecular Crystallography at PETRA III

Gleb Bourenkov (EMBL Hamburg, Germany)

EMBL-Hamburg operates two MX beamlines, P13 and P14, at PETRA III (DESY, Hamburg).On P13, combining X-rays in the 4-6 keV energy range with beam sizes down to 15 µm diameter while maintaining high photon flux allows to perform full anomalous data collections in less than 5 minutes. S-SAD phasing is achieved routinely. Diffraction measurements at low energies on P13 do not require any special preparation of the sample, i.e. a crystal attached to a standard SPINE-pin can be automatically mounted onto the goniostat.P14 can be run in two modes, one providing a collimated homogeneous beam that can be shaped to any size between 10 and 200 µm, the second mode producing micro-focus conditions with a beam size on the 5 µm scale. The collimated beam can be used to illuminate large (50-200 µm) and small crystals homogeneously and/or to resolve diffraction from large (>1000 Å) unit cells. The micro-focus beam can be used conveniently for serial data collections both on cryogenically cooled crystalline suspensions and in situ on crystals as grown in CrystalDirectTM crystallization plates. In situ structure determinations have been successfully performed from crystals in crystallization drops, in lipidic cubic phase, or as grown in living cells.In 2018, a second endstation ‘T-REXX’ has been added to P14 providing an environment optimized for pump-probe time-resolved experiments.The beamlines are part of the Integrated Facility for Structural Biology that offers access to services such as characterization of samples prior to crystallization, HT-crystallization, and crystal harvesting with a CrystalDirectTM Harvester.