Key stabilizing elements of protein structure identified through pressure and temperature perturbation of its hydrogen bond network

Nat Chem. 2012 Sep;4(9):711-7. doi: 10.1038/nchem.1396. Epub 2012 Jul 8.

Abstract

Hydrogen bonds are key constituents of biomolecular structures, and their response to external perturbations may reveal important insights about the most stable components of a structure. NMR spectroscopy can probe hydrogen bond deformations at very high resolution through hydrogen bond scalar couplings (HBCs). However, the small size of HBCs has so far prevented a comprehensive quantitative characterization of protein hydrogen bonds as a function of the basic thermodynamic parameters of pressure and temperature. Using a newly developed pressure cell, we have now mapped pressure- and temperature-dependent changes of 31 hydrogen bonds in ubiquitin by measuring HBCs with very high precision. Short-range hydrogen bonds are only moderately perturbed, but many hydrogen bonds with large sequence separations (high contact order) show greater changes. In contrast, other high-contact-order hydrogen bonds remain virtually unaffected. The specific stabilization of such topologically important connections may present a general principle with which to achieve protein stability and to preserve structural integrity during protein function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Humans
  • Hydrogen Bonding
  • Nuclear Magnetic Resonance, Biomolecular / methods
  • Pressure
  • Protein Conformation
  • Protein Stability
  • Proteins / chemistry*
  • Temperature
  • Ubiquitin / chemistry

Substances

  • Proteins
  • Ubiquitin