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High-throughput data collection requires seamless interoperation of various hardware components. In addition, user-supplied descriptions of protein crystals must be directly linked with the diffraction data. Such linkages can be achieved efficiently with computer databases. A database that tracks production of the protein samples, crystallization, and diffraction from the resultant crystals serves as the glue that holds the entire gene-to-structure process together. This chapter first discusses data collection processes and hardware. It then illustrates how a well-constructed database ensures information flow through the steps of data acquisition. With such a database, synchrotron beamline measurements can be directly and efficiently integrated into the process of protein crystallographic structure determination. The approaches to data acquisition summarized in the chapter apply to both the de novo determination of protein structures and, as is routine in drug discovery, examination of protein-ligand cocrystals.

This chapter begins by describing the other information gleaned from the diffraction patterns aside from recognizing the physical attributes of unit cell vectors provided in Chapter 4. It then provides techniques such as the oscillation method for the collection and analysis of the information obtained from the diffraction data of macromolecular crystals. Sample problems are also provided at the end of the chapter.

This chapter shows that the goal of structural analysis is to obtain the distribution of atomic electron density in the unit cell starting from the diffraction data. It is not possible to reach this goal in a unique and automatic way, because from the experimental data, only the magnitudes, but not the phases, of the structure factors may be obtained. Therefore, in order to compute the electron density, we must somehow derive the missing information. This chapter analyzes the most important methods commonly used to solve the phase problem. The problem must, in principle, have a solution, since the measured intensities are proportional to the squares of the structure factors.

This chapter illustrates the computations and variations of the electron density distribution of unit cells. To enable computations, crystallographers use electron density maps which are figured as a mathematical equation of square average value and standard deviation within a single unit cell. Chemical interpretations are derived from these maps and interpretability is dependent on crystallographic resolution. the chapter also examines the analyses on the effectivity of molecular models with the measured diffraction data. Sample problems are provided at the end of the chapter.