The energetics of a three-state protein folding system probed by high-pressure relaxation dispersion NMR spectroscopy.

ABSTRACT: The energetic and volumetric properties of a three-state protein folding system, comprising a metastable triple mutant of the Fyn SH3 domain, have been investigated using pressure-dependent (15) N-relaxation dispersion NMR from 1 to 2500 bar. Changes in partial molar volumes (ΔV) and isothermal compressibilities (ΔκT ) between all the states along the folding pathway have been determined to reasonable accuracy. The partial volume and isothermal compressibility of the folded state are 100 mL mol(-1) and 40 μL mol(-1)  bar(-1) , respectively, higher than those of the unfolded ensemble. Of particular interest are the findings related to the energetic and volumetric properties of the on-pathway folding intermediate. While the latter is energetically close to the unfolded state, its volumetric

SUBMITTER: Tugarinov V 

PROVIDER: S-EPMC4692720 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature