Conformational kinetics reveals affinities of protein conformational states.
Repository Usage Stats
Most biological reactions rely on interplay between binding and changes in both macromolecular structure and dynamics. Practical understanding of this interplay requires detection of critical intermediates and determination of their binding and conformational characteristics. However, many of these species are only transiently present and they have often been overlooked in mechanistic studies of reactions that couple binding to conformational change. We monitored the kinetics of ligand-induced conformational changes in a small protein using six different ligands. We analyzed the kinetic data to simultaneously determine both binding affinities for the conformational states and the rate constants of conformational change. The approach we used is sufficiently robust to determine the affinities of three conformational states and detect even modest differences in the protein's affinities for relatively similar ligands. Ligand binding favors higher-affinity conformational states by increasing forward conformational rate constants and/or decreasing reverse conformational rate constants. The amounts by which forward rate constants increase and reverse rate constants decrease are proportional to the ratio of affinities of the conformational states. We also show that both the affinity ratio and another parameter, which quantifies the changes in conformational rate constants upon ligand binding, are strong determinants of the mechanism (conformational selection and/or induced fit) of molecular recognition. Our results highlight the utility of analyzing the kinetics of conformational changes to determine affinities that cannot be determined from equilibrium experiments. Most importantly, they demonstrate an inextricable link between conformational dynamics and the binding affinities of conformational states.
Magnetic Resonance Spectroscopy
Published Version (Please cite this version)10.1073/pnas.1502084112
Publication InfoDaniels, Kyle G; Suo, Yang; & Oas, Terrence G (2015). Conformational kinetics reveals affinities of protein conformational states. Proc Natl Acad Sci U S A, 112(30). pp. 9352-9357. 10.1073/pnas.1502084112. Retrieved from https://hdl.handle.net/10161/10594.
This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.
More InfoShow full item record
Terrence Gilbert Oas
Professor of Biochemistry
Our laboratory is primarily interested in the mechanisms of protein folding. We use nuclear magnetic resonance (NMR) and other types of spectroscopy to study the solution structure, stability and folding reactions of small protein models. These include monomeric λ repressor, the B domain of protein A (BdpA) and various regulator of G-protein signalling (RGS) domains. Our biophysical studies are used to inform our investigations of the role of folding mechanism in the function of pro
Articles written by Duke faculty are made available through the campus open access policy. For more information see: Duke Open Access Policy
Rights for Collection: Scholarly Articles
Works are deposited here by their authors, and represent their research and opinions, not that of Duke University. Some materials and descriptions may include offensive content. More info
Showing items related by title, author, creator, and subject.
LKB1 Loss induces characteristic patterns of gene expression in human tumors associated with NRF2 activation and attenuation of PI3K-AKT. Kaufman, Jacob M; Amann, Joseph M; Park, Kyungho; Arasada, Rajeswara Rao; Li, Haotian; Shyr, Yu; Carbone, David P (Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer, 2014-06)Inactivation of serine/threonine kinase 11 (STK11 or LKB1) is common in lung cancer, and understanding the pathways and phenotypes altered as a consequence will aid the development of targeted therapeutic strategies. Gene ...
Amino acid permeases require COPII components and the ER resident membrane protein Shr3p for packaging into transport vesicles in vitro. Kuehn, MJ; Schekman, R; Ljungdahl, PO (J Cell Biol, 1996-11)In S. cerevisiae lacking SHR3, amino acid permeases specifically accumulate in membranes of the endoplasmic reticulum (ER) and fail to be transported to the plasma membrane. We examined the requirements of transport of the ...
G protein beta gamma subunits stimulate phosphorylation of Shc adapter protein. Touhara, K; Hawes, BE; van Biesen, T; Lefkowitz, RJ (Proc Natl Acad Sci U S A, 1995-09-26)The mechanism of mitogen-activated protein (MAP) kinase activation by pertussis toxin-sensitive Gi-coupled receptors is known to involve the beta gamma subunits of heterotrimeric G proteins (G beta gamma), p21ras activation, ...