PROTEOLYTIC TISSUE FERMENTS 91 



besides radium, 51 consideration of which in the treatment 

 of tumors has been given in an earlier lecture (v. Vol. I of 

 this series, pp. 557-558, The Chemistry of the Tissues), two 

 other great blessings to man, mercury and iodine, are to be 

 numbered among the agents capable of increasing autolysis. 

 While the addition of iodide of potassium to an autolysing 

 mass is without effect, a very decided increase of hepatic 

 autolysis has been attained in animals by long preadminis- 

 tration of the salts of iodine. 52 May it not be that the favor- 

 able influence, confirmed in hundreds of thousands of cases, 

 which this agent exerts upon luetic processes, is in some 

 way connected with stimulation of autolysis? The few* 

 observations here referred to give us, of course, no justifica- 

 tion for such a conclusion. But as a pointer for continued 

 investigation they deserve constant reflection. 



Abderhalden's Investigations Upon Proteolytic Tissue 

 Ferments. We are indebted for very real progress in the 

 study of proteolytic tissue ferments to the extensive investi- 

 gations of Emil Abderhalden and his army of collaborators. 53 

 By his method of work, testing the tissue enzymes, not as was 

 always done before upon indefinable proteins, but upon 

 numerous well-defined polypeptids, Abderhalden, it may be 

 said, dragged the whole problem from the depth of a dismal 

 cloud-mass into an enlightened level; and it is not a diffi- 

 cult thing to prophesy that when this series of studies has 



61 J. Wohlgemuth, Berliner klin. Wochenschr., 1904, No. 26, 704; S. 

 Lowenthal and E. Edelstein, Biochem. Zeitschr., 14, 484, 1908. 



62 L. Kepinow (Instit. for Cancer Investigation, Heidelberg), Biochem. 

 Zeitschr., 37, 238, 1911; L. B. Stookey, Proc. Soc. Exp. Biol., 5, 89; abst. in 

 Jahresb. f. Tierchem., 58, 842, 1908. 



* s E. Abderhalden, in association with C. Brahm, H. Deetjen, A. Gigon, M. 

 Guggenheim, A. Hunter, K. B. Immisch, A. Israel, E. Kampf, A. H. Koelker, W. 

 Manwaring, J. S. McLester, F. Lussana, L. Pinkussohn, A. Pringsheim, B. Opp- 

 ler, A. Rilliet, P. Rona, B. Schilling, A. Schittenhelm, J. G. Sleiswyk, E. Stein- 

 beck, J. Teruuchi, L. Wacker, W. Weichhardt. Literature: E. Abderhalden, 

 Lehrb. d. physiol. Chem., 2d ed., pp. 266-268, 1909; and Synthese der Zellbau- 

 steine in Pflanze und Tier, p. 119, Berlin, J. Springer, 1912; C. Oppenheimer, Die 

 Fermente, 3d ed., pp. 172-176, 1910. 



