X-ray crystallography is an important part in elucidating molecular mechanisms of biological reactions since begining of biophysics. Advance in x-ray crystallography techniques has made possible the structure determination of macromolecular assemblies and time-resolved structure analysis. X-ray crystallography will preserve a central role in understanding biological processes at atomic level.
NMR has become to be regarded as one of the powerful methods in structural biology. The outline of the method of the structure determination by NMR is shown, and an example of application to the C-terminal domain of the E. coli RNA polymerase α subunit is given. The contribution and future of NMR to the structural biology of our country will be discussed.
We have developed a high-resolution electron cryo-microscope by which images can be recorded with higher resolution than 3Å at a specimen-stage temperature of 4.2K. By using this instrument and electron crystallography the structures of Light-harvesting complex and bacteriorhodopsin were analysed at resolutions of 3.4Å and 3.0Å, respectively. The structure analysis of LHC gave the coordinates of twelve Chlorophyll molecules and two Lutein ones together with those including loops of the polypeptide chain. The result of bR resolved analyse atomic structurre from two dimensional crystals.
Neutron is effective and useful for the solution structural analysis of macromolecular complex. Recently, the movements of RNApolymerase on DNA double helix during transcription process have been investigated by neutron solution scattering. Protein dynamics are examined experimentally by neutron inelastic and quasielastic scattering. The dedicated neutron beam lines are required to promote the neutron structural biology in Japan.
As a larger number of three dimensional structures of biopolymers are determined experimentally, we are now beginning to ask "how and why" as to their biological functions. An essentially new aspect of structural biology exists in this point. In asking such questions theoretical studies play an indispensable role. Various aspects of structural biology in which theoretical studies are playing active roles are reviewed. The case of analysis of functions of electron transport proteins is discussed in detail.
The history of molecular biology is briefly described. The movement from molecular biology to structural biology seems to be an inevitable destination. Structural biology should be a biology, but this is not necessarily accepted by Japanese researchers analyzing Protein structures. Problems specific to Japanese structural biology are discussed.