Cosolute and Crowding Effects on a Side-By-Side Protein Dimer.

ABSTRACT: The effects of small (∼10² Da) and larger (>10³ Da) cosolutes on the equilibrium stability of monomeric globular proteins are broadly understood, excluding volume stabilizes proteins and chemical interactions are stabilizing when repulsive, but destabilizing when attractive. Proteins, however, rarely work alone. Here, we investigate the effects of small and large cosolutes on the equilibrium stability of the simplest defined protein-protein interactions, the side-by-side homodimer formed by the A34F variant of the 56-residue B1 domain of protein G. We used ¹⁹F nuclear magnetic resonance spectroscopy to quantify the effects of urea, trimethylamine oxide, Ficoll, and more physiologically relevant cosolutes on the dimer dissociation constant. The data reveal t

SUBMITTER: Guseman AJ 

PROVIDER: S-EPMC5985514 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature