Fluorometric Demonstration of Tryptophan in Dentin and Bone Protein

¹ Naval Medical Research Institute and the American Dental Association, Bethesda, Maryland

Fluorometric data obtained from basic hydrolysates (Ba[OH]₂) of bone and dentin protein were identical to standard solutions of tryptophan and tyrosine submitted to the same treatment. The presence of tryptophan in minute quantities (0.2%) in bone and dentin protein was indicated by the relative fluorescent efficiencies of the two calcified proteins following complete basic hydrolysis. Based on these data only, and even in the absence of corroborative chemical findings, it was reasonable and tempting to ascribe an authentic tryptophan residue to these calcified protein molecules.