title: Viscoelasticity in homogeneous protein solutions.
abstract: We probe the transport properties in protein solutions stable with respect to any, solid or liquid, phase separation as a step in the understanding of transport in the cytosol of live cells. We determine the mean-squared displacement of probe particles in the time range 10;{-3}-10 s in solutions of a model protein. The tested solutions exhibit significant elasticity at high frequencies, while at low frequencies, they are purely viscous. We attribute this viscoelasticity to a dense network of weakly-bound chains of protein molecules with characteristic lifetime of 10-100 ms. The found intrinsic viscoelasticity of protein solutions should be considered in biochemical kinetics models.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204-4004, USA.
authors.forename: Weichun
authors.initials: W
authors.lastname: Pan
authors.forename: Luis
authors.initials: L
authors.lastname: Filobelo
authors.forename: Ngoc D Q
authors.initials: ND
authors.lastname: Pham
authors.forename: Oleg
authors.initials: O
authors.lastname: Galkin
authors.forename: Veselina V
authors.initials: VV
authors.lastname: Uzunova
authors.forename: Peter G
authors.initials: PG
authors.lastname: Vekilov
mesh_terms: D003600:Cytosol / Q000737:chemistry / Q000378:metabolism; D004548:Elasticity; D007700:Kinetics; D008956:Models, Chemical; D009113:Muramidase / Q000737:chemistry / Q000378:metabolism; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012996:Solutions; D055682:Viscoelastic Substances / Q000737:chemistry* / Q000378:metabolism; D014783:Viscosity
chemical_list: D011506:Proteins; D012996:Solutions; D055682:Viscoelastic Substances; D012710:Serum Albumin, Bovine; D009113:Muramidase