45] Diazonium salts as specific reagents and probes of protein conformation

Abstract

Publisher Summary This chapter discusses procedures for the chemical modification of proteins with the common aromatic diazo reagents, for the determination of histidyl and tyrosyl residues in proteins with diazo-1 H-tetrazole, and for employing azochromophores as probes of local protein conformation. Quantitation of the modification can be carried out by spectral analysis if data are available on the absorption characteristics of the proper model compounds. Modification of a single protein with a series of different diazonium salts, however, gives a closely related family of similar dichroic spectra. This suggests that protein structure must play a major role in determining the details of these spectra. Substitutions with diazonium salts can be highly selective; modifying one or a very limited number of groups and assignments ultimately adding to the understanding of the relationship between protein structure and function can be anticipated.