Lack of Dependence of the Sizes of the Mesoscopic Protein Clusters on Electrostatics.

ABSTRACT: Protein-rich clusters of steady submicron size and narrow size distribution exist in protein solutions in apparent violation of the classical laws of phase equilibrium. Even though they contain a minor fraction of the total protein, evidence suggests that they may serve as essential precursors for the nucleation of ordered solids such as crystals, sickle-cell hemoglobin polymers, and amyloid fibrils. The cluster formation mechanism remains elusive. We use the highly basic protein lysozyme at nearly neutral and lower pH as a model and explore the response of the cluster population to the electrostatic forces, which govern numerous biophysical phenomena, including crystallization and fibrillization. We tune the strength of intermolecular electrostatic forces by varying the solution ionic str

SUBMITTER: Vorontsova MA 

PROVIDER: S-EPMC4643268 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature