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Keywords:

  • Surface mapping;
  • NMR;
  • photo-CIDNP;
  • TEMPOL;
  • protein folding

Abstract

  1. Top of page
  2. Abstract
  3. References

We have characterized the high-temperature molten globule state of bovine α-lactalbumin by a combined use of photochemically induced dynamic nuclear polarization and nitroxide surface perturbation. Both techniques are extremely well suited to follow the progressive increase of exposed surfaces in the native state and the appearance of partially or completely unfolded species. Our results suggest that the molten globule state obtained at high temperature and pH 7, and the state obtained at pH 2 are not only thermodynamically but also structurally very similar.

Abbreviations
Photo-CIDNP

photochemically induced dynamic nuclear polarization

CPMG

CarrPurcell-Meiboom-Gill

TOCSY

total correlation spectroscopy

NOESY

two-dimensional nuclear Overhauser effect

DQF-COSY

double quantum filtered correlated spectroscopy

ROESY

two-dimensional rotating-frame Overhauser effect spectroscopy

R

protein/TEMPOL ratio

TEMPOL

4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl

References

  1. Top of page
  2. Abstract
  3. References
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