PASE (PAramagnetic signals enhancement): a new method for NMR study of paramagnetic proteins.

A new method for NMR spectra acquisition of paramagnetic proteins is described, based on the simple use of homonuclear broadband decoupling of the diamagnetic region. Several advantages are associated with this method which was applied to one-dimensional spectra, to 1D NOE-difference spectroscopy, and to 2D NOESY. The main advantage is a very flat baseline obtained using the PASE (paramagnetic signals enhancement) method. Furthermore, the bulky region of the diamagnetic protons being suppressed, clean NOE-difference spectra can be acquired as well as improved 2D NOESY maps. Applications on 1D 1H spectrum of bovine liver catalase (MW 230,000), and 1D and 2D on the high-spin form of the myoglobin, used as a model protein, are presented.