Sulfate incorporation by embryonic chick bone the essentiality of sodium, of potassium, and of protein synthesis

Sulfate incorporation by emryonic chick pelvic rudiments requires protein synthesis.

The incorporation is also dependent on the presence in the incubation medium of both Na⁺ and K⁺, and is inhibitable by ouabain.

In the presence of Na⁺ and K⁺, the addition of amino acids to the incubation medium stimulates sulfate incorporation. If other monovalent cations are substituted for either Na⁺ or K⁺, sulfate incorporation in the absence of amino acids is decreased and stimulation by addition of amino acids is greatly reduced or eliminated.

The possibilities that the Na⁺ and K⁺ requirements are due to the participation by these ions in protein synthesis and in transport into the cell of amino acids, sulfate and glucose are discussed.