Solution NMR investigation of the response of the lactose repressor core domain dimer to hydrostatic pressure. Academic Article uri icon

abstract

  • Previous investigations of the sensitivity of the lac repressor to high-hydrostatic pressure have led to varying conclusions. Here high-pressure solution NMR spectroscopy is used to provide an atomic level view of the pressure induced structural transition of the lactose repressor regulatory domain (LacI* RD) bound to the ligand IPTG. As the pressure is raised from ambient to 3kbar the native state of the protein is converted to a partially unfolded form. Estimates of rotational correlation times using transverse optimized relaxation indicates that a monomeric state is never reached and that the predominate form of the LacI* RD is dimeric throughout this pressure change. Spectral analysis suggests that the pressure-induced transition is localized and is associated with a volume change of approximately -115mlmol-1 and an average pressure dependent change in compressibility of approximately 30mlmol-1kbar-1. In addition, a subset of resonances emerge at high-pressures indicating the presence of a non-native but folded alternate state.

published proceedings

  • Biophys Chem

altmetric score

  • 0.25

author list (cited authors)

  • Fuglestad, B., Stetz, M. A., Belnavis, Z., & Wand, A. J.

citation count

  • 8

complete list of authors

  • Fuglestad, Brian||Stetz, Matthew A||Belnavis, Zachary||Wand, A Joshua

publication date

  • December 2017