SIR2004 is the evolution of the SIR2002 program [Burla, Camalli, Carrozzini, Cascarano, Giacovazzo, Polidori & Spagna (2003). J. Appl. Cryst.36, 1103]. It is devoted to the solution of crystal structures by direct and Patterson methods. Several new features implemented in SIR2004 make this program efficient: it is able to solve ab initio both small/medium‐size structures as well as macromolecules (up to 2000 atoms in the asymmetric unit). In favourable circumstances, the program is also able to solve protein structures with data resolution up to 1.4–1.5 Å, and to provide interpretable electron density maps. A powerful user‐friendly graphical interface is provided.
SIR2014 is the latest program of the SIR suite for crystal structure solution of small, medium and large structures. A variety of phasing algorithms have been implemented, both ab initio (standard or modern direct methods, Patterson techniques, Vive la Différence) and non-ab initio (simulated annealing, molecular replacement). The program contains tools for crystal structure refinement and for the study of three-dimensional electron-density maps via suitable viewers.
IL MILIONE is a suite of computer programs devoted to protein crystal structure determination by X‐ray crystallography. It may be used in the following key activities. (a) Ab initio phasing, via Patterson or direct methods. The program may succeed even with structures with up to 6000 non‐H atoms in the asymmetric unit, provided that atomic resolution is available, and with data at quasi‐atomic resolution (1.4–1.5 Å). (b) Single or multiple isomorphous replacement, single‐ or multiple‐wavelength anomalous diffraction, and single or multiple isomorphous replacement with anomalous scattering techniques. In the first step the program finds the heavy‐atom/anomalous scatterer substructure, then automatically uses the above information to phase protein reflections. Phase extension and refinement are performed by electron density modification techniques. (c) Molecular replacement. The orientation and the location of the protein molecules are found via reciprocal space methods. Phase extension and refinement are performed by electron density modification techniques. All the programs integrated into IL MILIONE are controlled by means of a user‐friendly graphical user interface, which is used to input data and to monitor intermediate and final results by means of real‐time updated messages, diagrams and histograms.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.