Quantification of excluded volume effects on the folding landscape of Pseudomonas aeruginosa apoazurin in vitro.

ABSTRACT: Proteins fold and function inside cells that are crowded with macromolecules. Here, we address the role of the resulting excluded volume effects by in vitro spectroscopic studies of Pseudomonas aeruginosa apoazurin stability (thermal and chemical perturbations) and folding kinetics (chemical perturbation) as a function of increasing levels of crowding agents dextran (sizes 20, 40, and 70 kDa) and Ficoll 70. We find that excluded volume theory derived by Minton quantitatively captures the experimental effects when crowding agents are modeled as arrays of rods. This finding demonstrates that synthetic crowding agents are useful for studies of excluded volume effects. Moreover, thermal and chemical perturbations result in free energy effects by the presence of crowding agents that are identic

SUBMITTER: Christiansen A 

PROVIDER: S-EPMC3791299 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature