Concerning Histidine and Carnosine

Our knowledge of carnosine is largely due to the admirable investigations of Gulewitsch. The discovery of the base in beef muscle extract was first reported by Gulewitsch and Amiradiib? in 1900. Later Kutsche? isolated a substance from beef muscle extract, which he named ignotine, but Gulewitscl? showed that ignotine and carnosine were identical. In the same volume, he4 showed that hydrolysis of the base with barium hydroxide liberated the amino-acid, histidine. 5 years later, he5 established the identity of the other component, namely @-alanine. This aminoacid had been found in beef extract by Engeland,‘j as a result of the hydrolysis of carnosine during the process of isolation. Thus 11 years after its discovery, Gulewitsch showed that carnosine consisted of but two amino-acids, probably joined to form a dipeptide. Either one of two linkages was possible. Thus far no conclusive evidence had been advanced in favor of either formula. On the whole little has been done to establish the relative distribution, biological significance, and fate of carnosine in the