Time-domain THz spectroscopy reveals coupled protein-hydration dielectric response in solutions of native and fibrils of human lyso-zyme

Here we reveal details of the interaction between human lysozyme proteins, both native and fibrils, and their water environment by intense terahertz time domain spectroscopy. With the aid of a rigorous dielectric model, we determine the amplitude and phase of the oscillating dipole induced by the THz field in the volume containing the protein and its hydration water. At low concentrations, the amplitude of this induced dipolar response decreases with increasing concentration. Beyond a certain threshold, marking the onset of the interactions between the extended hydration shells, the amplitude remains fixed but the phase of the induced dipolar response, which is initially in phase with the applied THz field, begins to change. The changes observed in the THz response reveal protein-protein interactions me-diated by extended hydration layers, which may control fibril formation and may have an important role in chemical recognition phenomena

Spectral simplification techniques for high resolution fourier transform spectroscopic studies

Abstract not availabl

Spectral simplification techniques for high resolution fourier transform spectroscopic studies

Abstract not availabl

FOURIER TRANSFORM INFRARED EMISSION SPECTROSCOPY OF GAS-PHASE MnH, MnD AND YbH

Author Institution: Department of Physics, University of Waterloo; Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of WaterlooMolecules in the gas phase were generated in an emission source that combines a high temperature tube furnace with an electrical discharge. Infrared emission spectra of MnH/D in its ${^{7}}\Sigma^{+}$ ground state were recorded using a Fourier transform spectrometer at a resolution of $0.008 cm^{-1}$. The vibrational bands $v=1 \rightarrow 0$ to $v=3\rightarrow 2$ for MnH and $v=1\rightarrow 0$ to $v=4\rightarrow 3$ for MnD were observed. The vibration-rotation emission spectrum of YbH in its ${^{2}}\Sigma^{+}$ ground state was recorded at a resolution of $0.01 cm^{-1}$. Lines corresponding to five isotopomers of Yb were recorded for the $v=1\rightarrow 0$ band. In addition some weak electronic transitions of YbH/D in the near-infrared were observed and their analyses may be presented at the conference