The Effect of Phosphorylation of the Histidyl Residue in the Tetrapeptide Gly-Gly-His-Ala. Changes of Chemical Shift and pK-Values in ¹H- and ³¹P-NMR Spectra

Abstract

Phosphorylation of the tetrapeptide Gly-Gly-His-Ala by phosphoamidate provides a model peptide for proteins which, in the course of their reaction, bind a phosphoryl group to an imidazole ring. 31P- and 1H-NMR data, including chemical shift and pK values, for this peptide and its three phospho-derivatives are presented. These data show that it is possible, by NMR studies, to decide whether or not a peptide or a protein is phosphorylated at the N-1 or at the N-3 position of an imidazole ring, and how this information can be achieved.