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Dimensions, energetics, and denaturant effects of the protein unstructured state
Author(s) -
Li Maodong,
Liu Zhirong
Publication year - 2016
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1002/pro.2865
Subject(s) - protein folding , folding (dsp implementation) , förster resonance energy transfer , chemistry , energetics , native state , downhill folding , chemical physics , molten globule , random coil , phi value analysis , crystallography , thermodynamics , circular dichroism , physics , fluorescence , biochemistry , quantum mechanics , electrical engineering , engineering
Determining the energetics of the unfolded state of a protein is essential for understanding the folding mechanics of ordered proteins and the structure–function relation of intrinsically disordered proteins. Here, we adopt a coil‐globule transition theory to develop a general scheme to extract interaction and free energy information from single‐molecule fluorescence resonance energy transfer spectroscopy. By combining protein stability data, we have determined the free energy difference between the native state and the maximally collapsed denatured state in a number of systems, providing insight on the specific/nonspecific interactions in protein folding. Both the transfer and binding models of the denaturant effects are demonstrated to account for the revealed linear dependence of inter‐residue interactions on the denaturant concentration, and are thus compatible under the coil‐globule transition theory to further determine the dimension and free energy of the conformational ensemble of the unfolded state. The scaling behaviors and the effective θ‐state are also discussed.