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Acta Cryst. (2014). A70, C1377
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Since the 1980s, there has been great interest in how polypyridyl ruthenium complexes bind to DNA. This is due to their photoactive properties[1], which have great potential in photodynamic therapy, as they are able to damage DNA upon photoirradiation. However, there has been significant debate over the precise binding sites of these complexes due to the lack of definitive structural information. Presented here are several high resolution crystal structures showing how these complexes can bind to short DNA oligonucleotides. With each new structure we are able to answer questions about the binding geometry and step specificity which could explain the observations obtained from biophysical measurements in solution. We have shown that the complexes bind by intercalation as well as confirming a previously proposed binding mode, semi-intercalation. We have also shown that the complexes bind with a high level of sequence specificity[2], preferring TA steps over AT and CG and that each enantiomer can bind with a different orientation[3] (Figure 1). One obvious advantage to working with crystal samples is that they possess a well defined molecular structure, which can be determined and is therefore known. Spectroscopic experiments, with data collected in the picosecond and nanosecond timescale, will also be reported with these systems.

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Acta Cryst. (2014). A70, C1440
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DIALS is a collaborative initiative to produce an open source software toolbox encompassing all aspects of diffraction data analysis, with an initial focus on X-ray diffraction data from synchrotrons and free-electron lasers for macromolecular crystallography. DIALS [1] has been developed as a modular plug-in framework that permits flexibility not only in the development of new methods and algorithms but also in the application of these methods to data analysis. DIALS builds on the cctbx [2] in addition to its own dedicated tool-kits. We will present the ideas behind DIALS and give examples of its versatility in permitting the use of several spot-finding and indexing schemes, global refinement and both two and three dimensional integration methods.

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Acta Cryst. (2014). A70, C1447
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"In 2013 MX beamlines at the Diamond synchrotron deployed an automated software pipeline, called DIMPLE, for rapid processing of crystals that contain a known protein and possibly a ligand bound. DIMPLE takes the already known ""apo"" structure for the target protein, compares it with the electron density map from X-ray diffraction images, and visualizes areas of the electron density unaccounted for by the structure model. When processing batches of crystals, such feedback allows the user to better decide what to measure next which leads to a more efficient use of the beam time. This year we've enhanced the pipeline to cover more complex cases, including changes in the space group and some changes in conformation. With multiple molecular replacement computations run in parallel, the time from shooting to viewing the difference map is still only a few minutes. While the software is developed primarily for use at synchrotron beamlines, it is included in the CCP4 suite and can be used as well for in-house automation."
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