218 



be maintained. The way for further investigations should be left 

 open, but at any rate it seems nearer to the truth to suppose that 

 only great differences in speed of activity take place 1 ). Indeed the 

 experiments of Neuberg 2 ) on the action of bacteria, and those of 

 Pringsheim 3 ) on that of moulds, on racemoids, seem strongly to 

 confirm the last view. 



That from a physiological point of view there are undeniable 

 differences in the behaviour of living organisms towards enantio- 

 morphously related substances with which they are brought in 

 contact, is proved quite conclusively, and the same is the case also 

 for the human organism. Thus Piutti 4 ) already drew attention 

 to the fact that of both the isomeric optically active asparagines 

 the one component is sweet, the other insipid; and Menozzi and 

 Appiani 5 ) found the same fact in the case of glutaminic acid. 

 Poulsson 6 ) observed that from the racemic polypeptides twice as 

 much was necessary for nutrition, as when the optically active 

 form was used, while laevogyratory nicotine (from tobacco) is twice 

 as toxious as the synthetic ^^rogyratory alcaloid. Artificial adre- 

 naline is much less active than is the natural product, which is endowed 

 with rotatory power. The mydriatic action of atropine upon the 

 pupil of the eye is apparently specific for the natural base, while 

 its mirror-image does not show this property. The dextrogyrate 

 cocaine seems to paralyse the nerves of the tongue much more rapidly 

 than the laevogyrate alcaloid does. From this and similar examples 

 it is evident that in the assimilation-process of higher animals also, 

 enantiomorphously related molecules are by no means equivalent. 



Pasteur himself gave an explanation which, if followed, enables 

 us to bring this phenomenon within the scope of the arguments 

 given in the foregoing paragraphs referring to the second method 

 of fission. According to Pasteur's view, this selective action must, 

 beyond any doubt, depend on the dissimilar interaction of asymmetric 



1) K. Fajans, Zeits. f. phys. Chemie 73. 25; 75. 232. (1910). 



2) C. Neuberg, Biochem. Zeits. 18. 431. (1909). 



3) H. Pringsheim, Zeits. f. physiol. Chemie. 65. 96. (1910). 



4) A. Piutti, Compt. rend, de 1'Acad. d. Sc. Paris, 103. 134. (1886); L. 

 Pasteur, ibid. p. 138. 



&) A. Menozzi and G. Appiani, Atti R. Acad. Lincei (5) 2. //. 421. (1893). 



6) E. Poulsson, Archiv. exp. Path. u. Pharm. 27. 309. (1890); Ion, 2. 188. 

 (1910). Cf. also: C. Neuberg and J. Wohlgemuth, Ber. d. d. Chem. Ges. 

 34. 1745. (1901); Zeits. f. physiol. Chemie 35. 41. (1902); P. Mayer, Bioch. 

 Zeits. 1. 39. (1906). 



