We report here our study on ultrafast spectral dynamics in the interior of SNase using picosecond-resolved emission spectra of tryptophan through site-directed mutagenesis. By probing the solvation dynamics in the nucleotide binding pocket and the Ca²⁺ binding pocket as well as in the interior of hydrophobic core, two robust relaxation time scales on a few picoseconds and on tens of picoseconds have been observed. Both two time scales are strongly correlated with local structural and chemical properties of protein. These distinct differences in solvation dynamics reflect the intimate relationship between the dynamic structures and the functions of enzyme.

Date Published: 17 September 2014
PDF: 13 pages
Proc. SPIE 9230, Twelfth International Conference on Photonics and Imaging in Biology and Medicine (PIBM 2014), 92300M (17 September 2014); doi: 10.1117/12.2068901

Published in SPIE Proceedings Vol. 9230:
Twelfth International Conference on Photonics and Imaging in Biology and Medicine (PIBM 2014)
Qingming Luo; Lihong V. Wang; Valery V. Tuchin, Editor(s)