The availability of the acetyl derivatives of lysine for growth

Abstract

The biological behaviour of the amino-acid lysine is abnormal in several respects. In a number of experiments with isotopic nitrogen and hydrogen Schoenheimer and his collaborators [Foster, Schoen- heimer & Rittenberg, 1939; Schoenheimer, Ratner & Rittenberg, 1939 a, b; Weissman & Schoenheimer, 1941] have shown that, unlike most amino-acids, lysine does not accept N from other-.nitrogenous compounds, nor could deuterium bt introduced metabolically into this molecule. Itcappears that even the first stages of lysine metab;lism are irreversible. Until now no substances other than l-lysine have been found that w. 1 support the growth of young rats on a lysin -deficient diet.