title: Preferential solvation of lysozyme in dimethyl sulfoxide/water binary mixture probed by terahertz spectroscopy.
abstract: We report the changes in the hydration dynamics around a model protein hen egg white lysozyme (HEWL) in water-dimethyl sulfoxide (DMSO) binary mixture using THz time domain spectroscopy (TTDS) technique. DMSO molecules get preferentially solvated at the protein surface, as indicated by circular dichroism (CD) and Fourier transform infrared (FTIR) study in the mid-infrared region, resulting in a conformational change in the protein, which consequently modifies the associated hydration dynamics. As a control we also study the collective hydration dynamics of water-DMSO binary mixture and it is found that it follows a non-ideal behavior owing to the formation of DMSO-water clusters. It is observed that the cooperative dynamics of water at the protein surface does follow the DMSO-mediated conformational modulation of the protein.
authors.affiliation: Department of Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700098, India. Electronic address: chem2007dip@gmail.com.
authors.forename: Dipak Kumar
authors.initials: DK
authors.lastname: Das
authors.affiliation: Department of Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700098, India.
authors.forename: Animesh
authors.initials: A
authors.lastname: Patra
authors.affiliation: Department of Chemical, Biological and Macromolecular Sciences, S.N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700098, India. Electronic address: rajib@bose.res.
authors.forename: Rajib Kumar
authors.initials: RK
authors.lastname: Mitra
mesh_terms: D000818:Animals; D002645:Chickens; D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D005260:Female; D009113:Muramidase / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation / Q000187:drug effects; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D055068:Terahertz Spectroscopy; D014867:Water / Q000737:chemistry*
chemical_list: D012997:Solvents; D014867:Water; C421864:hen egg lysozyme; D009113:Muramidase; D004121:Dimethyl Sulfoxide
keywords: Collective hydration; Dimethyl sulfoxide; Lysozyme; Preferential solvation; Terahertz spectroscopy