Theory of molecular recognition and structural fluctuation of biomolecules

In this chapter, we present a theoretical treatment on the molecular recognition, one of elementary processes of life phenomena, based on the 3D-RISM/RISM theory. The theory has been applied successfully to a variety of molecular recognition processes. It has proved its ability to discriminate molecules having different charges and structures, which is an essential requirement for the in silico drug design. The structural fluctuation plays a crucial role in the process where a protein expresses its function. A new theory to characterize the structural fluctuation of protein around its native state, which combines the 3D-RISM/RISM theory with the generalized Langevin theory, is also presented here.