title: Mapping hydration dynamics around a protein surface.
abstract: Protein surface hydration is fundamental to its structure and activity. We report here the direct mapping of global hydration dynamics around a protein in its native and molten globular states, using a tryptophan scan by site-specific mutations. With 16 tryptophan mutants and in 29 different positions and states, we observed two robust, distinct water dynamics in the hydration layer on a few ( approximately 1-8 ps) and tens to hundreds of picoseconds ( approximately 20-200 ps), representing the initial local relaxation and subsequent collective network restructuring, respectively. Both time scales are strongly correlated with protein's structural and chemical properties. These results reveal the intimate relationship between hydration dynamics and protein fluctuations and such biologically relevant water-protein interactions fluctuate on picosecond time scales.
authors.affiliation: Department of Physics, Ohio State University, Columbus, OH 43210, USA.
authors.forename: Luyuan
authors.initials: L
authors.lastname: Zhang
authors.forename: Lijuan
authors.initials: L
authors.lastname: Wang
authors.forename: Ya-Ting
authors.initials: YT
authors.lastname: Kao
authors.forename: Weihong
authors.initials: W
authors.lastname: Qiu
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.forename: Oghaghare
authors.initials: O
authors.lastname: Okobiah
authors.forename: Dongping
authors.initials: D
authors.lastname: Zhong
mesh_terms: D001059:Apoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D009154:Mutation / Q000235:genetics; D009211:Myoglobin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D013499:Surface Properties; D013997:Time Factors; D014867:Water / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D001059:Apoproteins; D009211:Myoglobin; C010857:apomyoglobin; D014867:Water