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Acta Cryst. (2014). A70, C781
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The CCP4 software suite [1] provides a comprehensive set of tools for use in the macromolecule structure solution process by X-ray crystallography. Traditionally, these tools have been run through the graphical interface or the command line on each user's personal workstation. Recently, some of the tools, including the molecular replacement pipelines Balbes [2] and MrBUMP [3] have been provided as web services in the Research Complex at Harwell. These pipelines can be especially useful in cases where there is low sequence identity between the target-structure sequence and that of its set of possible homologues. These services can be accessed through a web client, allowing one to submit molecular replacement jobs to our Linux cluster and view the results from these jobs. The molecular replacement pipelines are ideal candidates for web services, as they require installation and maintenance of large databases and benefit from parallel computing resources, provided by the cluster. Further plans for web services will be discussed. With ever-increasing mobility of scientific setups and the ubiquity of ultra-portable devices, there is a demand for a consistent framework of remote crystallographic computations and data maintenance. This framework is planned to include an interface for synchronising data with the facilities of Diamond Light Source, as well as with local CCP4 GUI-2 setups.

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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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Acta Cryst. (2014). A70, C1723
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CCP4 has been serving the software needs of the protein crystallography community for more than 30 years. In this time the CCP4 Suite of software has been refined through contributions from some of the leading developers in the field of protein crystallographic software and the feedback of both expert and novice users. Today it is a highly comprehensive suite, providing tools and packages covering all aspects from data collection through to structure deposition. Here we will present details of the latest release series of the Suite, version 6.4. This release brings updates to many of the key elements in the Suite. The most obvious of these is the integration of the rolling updates mechanism. This is used to distribute timely fixes, update existing programs and introduce new functionality to users of the suite. Recent updates have seen updates to major programs such as phaser and imosflm/mosflm, and the introduction of a major overhaul of the Experimental Phasing pipeline Crank. An overview is given of the operation behind the updates and releases, including the jhbuild system, repositories and testing, the availability of nightly builds, and work towards the next major release of CCP4. This will see the integration of the CCP4MG package, along with preparations for the introduction of the long awaited CCP4i2.

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Acta Cryst. (2014). A70, C1745
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PISA (Protein Interfaces, Surfaces and Assemblies) software from CCP4 remains a popular computational tool for the prediction of biological assemblies (complexes) from macromolecular crystallography data [1]. The method is based on the estimation of the dissociation free energy of predicted complexes, and reaches 90-95% correct results for the current content of the PDB. It was found that the probability of getting wrong predictions grows exponentially with the decrease in the dissociation free energy, reaching over 50% for complexes bound as weakly as few kcal/mol [2]. Among few reasons for this behaviour [2] is the fact that oligomeric state of weakly bound complexes is expected to vary in dependence of chemical environment, in particular, protein concentration. It has been noticed in multiple use cases, that a considerable share of disagreements between predicted and measured oligomeric states belongs to situations where the relation between experimental conditions and protein's working environment in the cell is unclear. We report further advance in PISA software, which allows a researcher to model concentration dependence of predicted oligomeric states, and by this to improve interpretation of both experiments and computations in the biologically interesting case of weakly bound macromolecular associations. The new PISA is based on the concept of assembly stock, which represents an equilibrated set of of all complexes, compatible with crystal packing. Graphical representation of concentration (or newly introduced aggregation index) profiles of stock's components allows a user to quickly identify the most probable oligomeric state. This is vastly superior over the previous way of analysis, based on the interpretation of bare figures for dissociation free energies. Other developments include advanced graphical interface and multi-parametric interaction radar, which indicates the likelihood for interface to represent a biologically-relevant interaction.
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