Monitoring ¹⁵N Chemical Shifts During Protein Folding by Pressure-Jump NMR.

ABSTRACT: Pressure-jump hardware permits direct observation of protein NMR spectra during a cyclically repeated protein folding process. For a two-state folding protein, the change in resonance frequency will occur nearly instantaneously when the protein clears the transition state barrier, resulting in a monoexponential change of the ensemble-averaged chemical shift. However, protein folding pathways can be more complex and contain metastable intermediates. With a pseudo-3D NMR experiment that utilizes stroboscopic observation, we measure the ensemble-averaged chemical shifts, including those of exchange-broadened intermediates, during the folding process. Such measurements for a pressure-sensitized mutant of ubiquitin show an on-pathway kinetic intermediate whose ¹⁵N chemical shifts dif

SUBMITTER: Charlier C 

PROVIDER: S-EPMC6119464 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature