Quantifying the thermodynamics of protein unfolding using 2D NMR spectroscopy

August 21, 2020

Title

Quantifying the thermodynamics of protein unfolding using 2D NMR spectroscopy

Author

Rita Puglisi, Oliver Brylski, Caterina Alfano, Stephen R. Martin, Annalisa Pastore & Piero A. Temussi

Year

2020

Journal

Communications Chemistry volume 3, Article number: 100 (2020)

Abstract

A topic that has attracted considerable interest in recent years is the possibility to perform thermodynamic studies of proteins directly in-cell or in complex environments which mimic the cellular interior. Nuclear magnetic resonance (NMR) could be an attractive technique for these studies but its applicability has so far been limited by technical issues. Here, we demonstrate that 2D NMR methods can be successfully applied to measure thermodynamic parameters provided that a suitable choice of the residues used for the calculation is made. We propose a new parameter, named RAD, which reflects the level of protection of a specific amide proton in the protein core and can guide through the selection of the resonances. We also suggest a way to calibrate the volumes to become independent of technical limitations. The methodology we propose leads to stability curves comparable to that calculated from CD data and provides a new tool for thermodynamic measurements in complex environments.

Instrument

J-815

Keywords

Circular dichroism, proteins, thermodynamics, Nuclear magnetic resonance, NMR