Two‐dimensional 1H‐nmr studies on the lac repressor DNA binding domain: Further resonance assignments and identification of nuclear overhauser enhancements

The assignments of several 1H lines in the spectrum of the lac repressor DNA‐binding domain (or “headpiece”) are documented. These new assignments complement those obtained in a previous study [E.R.P. Zuiderweg, R. Kaptein, and K. Wüthrich (1983) Eur. J. Biochem. 137, 279] and were made from pure absorption phase two‐dimensional nuclear Overhauser enhancement (2D NOE) spectra and 1H 2D double‐quantum spectra of this protein. Based on the complete set of resonance assignments, a large number of interresidue NOEs are identified; these are documented and their relation with distance constraints is discussed. The identification of these NOEs is a prerequiste for the determination of the spatial structure of this protein, for which no crystallographic data are available.