Enzymatic Formation of Glutamohydroxamic Acid from Glutamine in Mammalian Tissue

Abstract

THE presence of enzymes which catalyse the exchange of the amide group of glutamine and asparagine with amines^1–3 has been shown in cell-free extracts of micro-organisms. The enzymatically catalysed exchange can be easily detected and assayed with hydroxylamine as the acceptor amine, since the γ-glutamo and β-asparto hydroxamic acids produced give the colour reaction with ferric chloride characteristic for hydroxamic acids. The terms ‘glutamo-’ and ‘asparto-transferase’ activities were proposed for these enzymatic potencies, since the mechanism of the exchange can be visualized as a transfer of the amino-acid radical from one amine to another.