Premium
Native and Unfolded States of Phosphoglycerate Kinase Studied by Single‐Molecule FRET
Author(s) -
Rosenkranz Tobias,
Schlesinger Ramona,
Gabba Matteo,
Fitter Jörg
Publication year - 2011
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.201000701
Subject(s) - förster resonance energy transfer , phosphoglycerate kinase , guanidine , chemistry , native state , crystallography , population , chemical physics , single molecule fret , molecule , biophysics , biochemistry , biology , enzyme , organic chemistry , physics , demography , quantum mechanics , sociology , fluorescence
Single‐molecule Förster resonance energy transfer (FRET) measurements with phosphoglycerate kinase from yeast were performed at different concentrations of guanidine hydrochloride. From these steady‐state measurements we obtained FRET efficiency histograms characterizing structural properties of individual proteins at different stages between the native and the fully unfolded state. Native proteins exhibit a slightly more expanded structure under buffer conditions without denaturant as compared to conditions with denaturant. At 0.5 M GndHCl an unfolded state population that exhibits a significantly expanded structure as compared to the native state, emerges. The unfolded state is characterized by a pronounced broadening of the efficiency distribution, which indicates a large structural and/or dynamical heterogeneity within the population. At high denaturant concentrations, well above the unfolding transition at C 1/2 ∼0.7 M , we observe a progressive expansion of the protein structure, namely globule–coil transition.