NMR Studies of Partially Folded Molten-Globule States

  • Christina Redfield
Part of the Methods in Molecular Biology™ book series (MIMB, volume 278)

Abstract

Nuclear magnetic resonance (NMR) spectroscopy is a powerful technique for the study of the structure, dynamics, and folding of proteins in solution. It is particularly powerful when applied to dynamic or flexible systems, such as partially folded molten-globule states of proteins, which are not usually amenable to X-ray crystallography. This chapter describes NMR methods suitable for the characterization of molten-globule states. These include pulsed-field-gradient NMR techniques for the measurement of the hydrodynamic radius, bulk and site-specific hydrogen-deuterium exchange experiments for the identification of regions of secondary structure, and 15N-edited NMR experiments carried out in increasing concentrations of denaturants, which allow the stability of different regions of the molten globule to be probed. Examples of the application of these methods to the study of the low-pH molten globule of human α-lactalbumin are presented.

Key Words

Molten globule partially folded protein protein folding protein denaturation hydrogen-deuterium exchange circular dichroism ANS fluorescence hydrodynamic radius HSQC α-lactalbumin PG-SLED resonance assignment 

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Copyright information

© Humana Press Inc., Totowa, NJ 2004

Authors and Affiliations

  • Christina Redfield
    • 1
  1. 1.Oxford Centre for Molecular SciencesUniversity of OxfordOxfordUK

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