Développement et applications de méthodes RMN rapides pour l'étude de la structure et la dynamique des protéines

Multidimensional (nD) NMR is the method ofchoice for atom-resolved studies ofprotein structure and dynamics in solution. Among its current limitations are the long acquisition times required, translating to experimental times of several days or weeks for the set of experiments required for structural studies of proteins. Furthermore, real-time studies of kinetic processes occurring on a seconds time sc ale are inaccessible to standard nD NMR. This thesis is concerned with the development of fast nD NMR techniques based on longitudinal relaxation optimization. It is shown that 2D 1H-15N (3D 1H-15N-13C) correlation spectra can be obtained in only a few seconds (few minutes) of acquisition time for samples at millimolar concentration. Ln addition, the longitudinal relaxation optimized methods, when combined with alternative data sampling such as spatial or Hadamard encoding, can yield site-resolved 2D1H-15N correlation spectra in acquisition times down to one second. Applications of fast 2D methods to the study ofprotein folding and unfolding are shown. This thesis also presents a longitudinal relaxation optimized method for the sensitivity-enhanced measurement ofresidual dipolar couplings between amide protons, as well as a fast and simple experiment for the characterization of protein samples, which can be very useful in the context of screening of sample conditions.