S30 THE BACTERIOPHAGE 



trate is constant for each phage and is independent of the bacterial substratum whicli 

 was used to obtain the active filtrate.' 



As for the phage-inhibiting activity of antibacterial sera, it has been demonstrated 

 that this action is not directed against the phage, but against the bacteria, rendering 

 them less susceptible to lysis. It has been suggested that this effect is probably due 

 to the saturation by agglutinins of receptors susceptible to union with phage.^ 



It appears then that when filtrates of lysed cultures are used in immunization 

 of animals, the agent of transmissible lysis acts as a specific antigen, independently 

 of other antigens, notably those of bacterial origin, present in the filtrates at the 

 same time. The question naturally arises: Is the active agent therefore to be con- 

 sidered an autonomous, organized being, totally foreign to bacteria and multiplying 

 at their expense, or can it still be a product of bacteria, accumulating in the culture 

 during the growth or during the lysis of bacteria, but antigenically distinct from 

 them? 



ASSIMILATION OF BACTERIAL SUBSTRATUM BY BACTERIOPHAGE 



According to D'Herelle, in order that the bacterial substratum, at the expense 

 of which the bacteriophage apparently multiplies, may be thus gradually transformed 

 into antigenically distinct substratum of bacteriophage, the latter must be alive and 

 "must" possess an autonomous metabolism, independent of bacterial metabolism.'^ 

 In the absence of direct evidence of the existence of such metabolism, D'Herelle relies 

 on the supporting evidence supplied by Wollman, and confirmed by Asheshov, and 

 concludes that "multiplication of bacteriophage corpuscles can take place, at least 

 to a certain degree, even in the absence of the bacterial cell. For this develop- 

 ment the corpuscles utilize certain diffusible products present in the culture of sus- 

 ceptible bacteria. "4 However, the findings of Wollman^ (since questioned by the au- 

 thor himself)'' seem to be susceptible to a different and more adequate interpreta- 

 tion, and in the light of the findings of the writer^ do not indicate any assimilation 

 of the bacterial products by the bacteriophage. 



•Jotten^ also concluded that bacteriophage may multiply in the absence of ac- 

 tively growing bacteria. His findings suggesting that Bacteria phagum intestinale may 

 utilize dead susceptible bacteria have not been confirmed, however.^ 



The recent evidence of Twort that dead bacteria may undergo lysis, if, in addition 



' Seiffert, W.: Ztsckr. f. rmmnnitdlsforsch. u. exper. Thcrap., 38, 301. 1923; Wagemans, J.: Arch. 

 iutcrnat. pharmac. et therap., 28, 181. 1923; Bruynoghe, R.: Arch, internal, med. exper., i, 17. 1924; 

 BrujTioghe, R., and Dubois, A.: Compt. rend. See. de bioL, 96, 211. 1927. 



^ Marcuse, K.: loc. cil.; da Costa Cruz, J.: op. cit., 93, 875. 1925. 



sReichert, F.: loc. cil.; d'Herelle, F.: Com pi. rend. Soc. de biol., 90, 25. 1924. 



•'d'Hcrelle, F.: The Baclerio phage and lis Behavior, pp. 102-3. 1926. 



sWoUman, Iv: Compl. rend. Soc. de biol., 84, 3. 1921. 



* Wollman, E.: Ann. dc I'lnsl. Pasleiir, 39, 7S9. 1925. 



' Bronfenbrenncr, J., and Muckenfuss, R.: J Exper. Med., 45, 887. 1927. 



^ Jiilten, K. W.: Klin. Wchnschr., 1, 2181. 1922. 



' Bronfenljicnntr, J., and Muckenfuss, R.: loc. cil.; Otto, R., Munter, M., and Winkler, W. F.: 

 Zlschr.f. Ilyg. n. Iiifcl-liotishranlch., 96, 1 18. 1922; t)()err, R., and (iruninger, W.: //»/(/., 97, 209. 1923; 

 SeilTcrt, W.: Zlschr.f. I iinnuniliihjorsch. 11. exper. Tlr-riip., 38, 292. 1923-24. 



