1. Structural Biophysics Laboratory, Harima Institute, The Institute of Physical and Chemical Research (RIKEN), SPring-8, Mihara, Mikazuki, Sayo, Hyogo 679-5143, Japan, Department of Chemistry, Faculty of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan, and Division of Biophysical Engineering, Graduate School of Engineering Science, Osaka University, Machikane-yama, Toyonaka 560-8531, Japan