Separation of Protein and Water Dynamical Transitions Using Terahertz Spectroscopy

ORAL

Abstract

Terahertz Time Domain spectroscopy (THz TDS) has been used to characterize the protein dynamical transition [1, 2]. The dynamical transition has been considered a manifestation of the slaving of protein motions to thermally activated motions of the solvent, however recently is has been reported that sharp temperature increases in protein dynamics occur independent of the solvent [3]. Potentially terahertz spectroscopy can resolve both the protein and water dynamical transitions using the ~ 5 THz intermolecular water vibrational line and the broad ~ 1.0 THz absorption arising from the protein intramolecular motions. Here we use a combination of THz TDS and FTIR to examine this possibility and resolve the protein and water contributions using a combination of spectral decomposition and concentration dependent measurements. Concentration dependent measurements using hen egg white lysozyme (HEWL) confirm that the transition measured at 1 THz is dominated by the protein dynamics.
1. He, Y.F., et al., Phys. Rev. Lett., 2008. DOI: 10.1103/PhysRevLett.101.178103.
2. Markelz, A.G., et al., Chem. Phys. Lett., 2007. DOI: 10.1016/j.cplett.2007.05,080.
3. Liu, Z., et al., Phys. Rev. Lett., 2017. DOI: 10.1103/PhysRevLett.119.048101.

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Presenters

  • AKANSHA SHARMA

    University at Buffalo, The State University of New York

Authors

  • AKANSHA SHARMA

    University at Buffalo, The State University of New York

  • Deepu George

    Physics, University at Buffalo, Department of Physics, University at Buffalo, Buffalo, New York, United States, University at Buffalo, The State University of New York

  • Andrea Markelz

    Physics, University at Buffalo, Physics, University at Buffalo, The State University of New York, Department of Physics, University at Buffalo, Buffalo, New York, United States, University at Buffalo, The State University of New York