UV synchrotron radiation chiral spectroscopy to characterize the structure of biomolecules

Chirality is an important structural factor in understanding the functions and properties of substances, and a circular dichroism (CD), which observes the interaction with UV circularly-polarized light, is a powerful chiral spectroscopic method for studying the structure and function of biomolecules containing chirality. A vacuum-ultraviolet circular-dichroism (VUVCD) spectroscopy using an UV synchrotron radiation greatly expanded the utility of CD spectroscopy for the structural analysis of biomolecules by combining with computational techniques and bioinformatics. This spectroscopy provided the absolute configurations of natural products including saccharides with higher energy chromophores (allene, acetal bond, and hydroxy group) and the combination with molecular-dynamics simulation in water molecules disclosed their hydrations including the intramolecular and intermolecular hydrogen bonds. This spectroscopic technique combined with bioinformatics also successfully estimated the secondary-structure contents, numbers of segments, and sequences of native proteins and non-native proteins such as membrane-bound proteins. Further, the time-resolved technique with microfluidic device made it possible to exhibit structural dynamics or kinetic studies of protein interacting with membrane at the molecular level. The CD technique with SR light source would enhance the performance of chiral spectroscopy, opening a pathway of next-generation of molecular chirality research.