11. Conclusion

The crystallography of biological macromolecules occupies a central place in modern biology, as the three-dimensional structure of a macromolecule or macromolecular complex sheds new and original light that is essential for understanding biological function. In most cases, this is a revolution, and several Nobel Prizes have crowned the most outstanding successes. Purification of the macromolecule(s) and obtaining quality crystals (diffraction limit better than 3 Å) are still two limiting stages in any structural project. What's more, solving the phase problem is still in some cases a long and tedious process, particularly for large macromolecular edifices. In simple cases, 3D structures are routinely determined from a very limited number of crystals, sometimes of very small sizes (a few micrometers), with a minimum of human intervention. By simple cases we mean macromolecules which, given...