Protein synthesis in guinea-pig liver; incorporation of radioactive amino acids into proteins of the microsome fraction in vivo.

Hobson & Rees, 1955) and served to identify them by synthetic as opposed to degradative means. Throughout the species investigated the phosphokinases predicted by the previous results were all proved to be present and capable ofphosphorylating the expected base. As was reported for some of the echinoderms (Needham & Baldwin, 1937), several annelids, e.g. Glycera gigantea, Nerei8 diversicolor and Myxicola infundibulum, contain a mixture of phosphagens and show that the enzyme systems for the synthesis and utilization of phosphagens in living muscle are completely duplicated. The experimental results again emphasize that creatine phosphate, acting as a phosphagen, is not confined to the echinoderms, protochordates and vertebrates, but is also present, often in considerable quantities, in the annelids. At the present time the distribution of creatine phosphate appears quite arbitrary. This fact lessens the value of the identification of the phosphagens in evolutionary studies in the animal kingdom.