Interactions of a Polypeptide with a Protein Nanopore Under Crowding Conditions.

ABSTRACT: Molecular crowding, a ubiquitous feature of the cellular environment, has significant implications in the kinetics and equilibrium of biopolymer interactions. In this study, a single charged polypeptide is exposed to competing forces that drive it into a transmembrane protein pore versus forces that pull it outside. Using single-molecule electrophysiology, we provide compelling experimental evidence that the kinetic details of the polypeptide-pore interactions are substantially affected by high concentrations of less-penetrating polyethylene glycols (PEGs). At a polymer concentration above a critical value, the presence of these neutral macromolecular crowders increases the rate constant of association but decreases the rate constant of dissociation, resulting in a stronger polypeptide-por

SUBMITTER: Larimi MG 

PROVIDER: S-EPMC6482057 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature