87 



niajdes, Toriila monosa, Saccharomjces cerevisiae and Lactose-yeast 

 can be cultivated, without volutin being generated in the cells. On 

 transplantation into a phosphate-containing medium a fresh formation 

 of volutin ensues. 



With dilute alkali a nucleinic-acid compound is extracted along 

 with volutin from Torula monosa and Saccharomyces cerevisiae, 

 which cannot be obtained from an approximately equal quantity of 

 volutin-free culture. The hypothesis, never proved before, though 

 indirectly supported, that volutin consists of a nucleinic-acid compound, 

 has thus been placed beyond dispute. Nucleinic-acid pi-epared from 

 yeast in the usual way originates no doubt chiefly from volutin. 



The nucleinic-acid compound dissolved from the volutin-containing 

 cells, is decomposed by a nuclease formed in the Torula-cells 

 themselves, in which process the development of phosphoric acid 

 could be demonstrated. Also the volutin-free cultures of Torula 

 monosa still contain a nuclease. Other enzymic actions also continue, 

 e. g. the katalase- and the zymase-action. Contrary to Henneberg's 

 recent pronouncement that the zymase-action of the yeast depends 

 on the presence of volutin, that the latter is probably to be con- 

 sidered, as the enzyme itself, it may be proved that volulin-free 

 cultures still evolve a very distinct fermentation. Considering the 

 slower growth in a phosphate-free medium, this fermentation is not 

 appreciably infei-ior to the fermenting power of the volutin-cultures 

 of Torula and Saccharomyces. Even after a sojourn of "9 months 

 in a phosphate-free environment a volutin-free culture of Torula 

 monosa is still liable to fermentation. 



Volutin is a nucleinic-acid compound which is presumably nothing 

 but a reserve-material. The presence of this reserve-material 

 though it is not indispensable to the life and the multiplication of 

 cells, is no doubt of great moment for their individual develop- 

 ment. There is reason to believe that, though not being required 

 for the fermentation, it facilitates the fermenting pi-ocess by contin- 

 ually supplying small amounts of phosphate, which can be liberated 

 from the nucleinic-acid by the nuclease. The relationship of the 

 volutin to the multiplication of the cells is a subject that must be 

 left for fuither investigation. 



Upon a phosphate-free medium with Torula monosa a pigmented 

 variation was once developed with fine brown pigment-granules. 

 This pigment disappeared after transplantation upon a phosphate- 

 containing medium but recurred repeatedly in a phosphate-free medium. 

 Also these pigment-containing cultures had retained the glycose- 

 splitting enzyme. 



