The X-ray structures of myoglobin and hemoglobin initiated structural biology around 1960. By exploiting synchrotron radiation and gene engineering, protein crystallography has become a powerful tool in structural biology. To date, the atomic coordinates of more than 35, 000 proteins and nucleic acids are known, which has expanded the fundamental knowledge of protein and nucleic acid structures. Current protein crystallography would not be possible without synchrotron radiation. However, structural studies of biological macromolecular assemblies, including tentative protein complexes, must be accelerated to establish a collaborative relationship with system biology, a novel biological field. Another important structural study in the coming decade is the highly accurate structural determination in combination with other methods to elucidate reaction mechanism in anisotropic reaction fields of proteins.
