THE MECHANISM OF PEPSIN ACTION

18 White, IF. G., and L. L. Ingraham, J. Am. Chem. Soc., 82, 4114 (1960). 19 Stadtman, E. R., and H. A. Barker, J. Biol. Chem., 184, 769 (1950). 20 Lipmann, F., and L. C. Tuttle, J. Biol. Chem., 159, 21 (1945). 21 Stadtman, E. R., J. Biol. Chem., 196, 527 (1952). 22 Rose, I. A., M. Grunberg-Manago, S. R. Korey, and S. Ochoa, J. Biol. Chem., 211, 737 (1954). 23 IDP was used instead of ADP to circumvent interference by adenylate kinase,24 which was present in the acetokinase preparation. 24 Kaplan, N. O., in Methods in Enzymotogy, eds. S. P. Colowick and N. 0. Kaplan (New York: Academic Press, 1957), vol. 3, p. 873. 25 Kornberg, A., J. Biol. Chem., 182, 779 (1950). 26 Friedemann, T. E., and G. E. Haugen, J. Biol. Chem., 147, 415 (1943).