In this project, I will investigate, at the molecular level, "interplay
between the interacting schemes of bio-molecules in solution and their specific
functions" and "a self-organization mechanism of proteins into
higher-order structures". These subjects are crucial because they are
closely related not only to solution chemical physics, soft-matter/colloid
physics, and biophysics, but to a wide range of interdisciplinary fields,
e.g., life science and medical applications.
For instance, to clarify the diversity of hydrophobic interaction,
which is known to be a major driving force of self-organization phenomena
of all amphiphilic molecules, stabilization of higher-order structures of
proteins, and so forth, we need to seek microscopic aspects of liquid water,
such as degree of freedom for its translational motions and microscopic
frictional forces acting on the cooperative rearrangement hydrogen-bond
network. On the one hand, if jumping to the hierarchy of colloid, protein-protein
interactions in vivo is considered not to be independent of the concentration
of other coexisting molecules; a remarkable influence of "depletion
interaction", i.e., an apparent attractive interaction between large
particles under coexistence of large and small colloidal particles, is expected
to emerge.
Using novel experimental and analytical approaches, mainly based on
small-angle scattering, dynamic and static light scattering, and dielectric
spectroscopy, I will try to establish the system that enables us to pursuit
a variety of phenomena occurring on extremely wide time- and length-scale.
This way, I cultivate the frontiers of solution chemical physics, soft-material/colloid
physics, and biological physics. I believe that there is possibility that
in the future, we are able to understand, with certain universality, such
diverse phenomena from a universal standpoint where each hierarchy is transcended.
At the same time, I am hoping to contribute, from the viewpoint of
physics, to the development of bio-inspired materials aiming at medical
applications, like artificial oxygen carriers.