2D FT-IR spectroscopy analysis of the pressure-induced changes in proteins

In this paper, we al,ply for the first time two-dimensional (2D) correlatio n spectroscopy to analyze pressure-induced changes in proteins. We show tha t it is possible to distinguish between hydrogen-deuterium (H/D) exchange a nd conformational changes from the synchronous and the asynchronous spectra . From the sequence of the spectral changes it can be concluded that the in itial partial unfolding of the secondary structure enhances the exchange, w hich is followed by further conformational changes. The exchange process is complete below ca. 0.4 GPa. The elastic distortions of the protein at high er pressures seem not to be accompanied by H/D exchange. (C) 1999 Elsevier Science B.V. All rights reserved.