78 PHYSIOLOGY OF YEASTS 



carbonic acid and water in aerobic life, or into carbonic acid and 

 alcohol in anaerobic life. 



Kohl holds the same opinion based on the following: Glycogen 

 is especially abundant in yeast cells during active fermentation. It 

 is not found in cells about to sporulate or in ascospores. Our ob- 

 servations have shown on the contrary that glycogen is very abun- 

 dant, not only during fermentation but also during the formation of 

 ascospores in the course of their maturation. Part is used in the 

 formation of the ascospore while the rest is kept in reserve for their 

 germination. The investigations of Will have shown that the durable 

 cells contain large quantities of glycogen. These facts do not exclude 

 the theory of Griiss, for it is possible that glycogen is a reserve prod- 

 uct especially for respiration. 



Henneberg l states that glycogen may occur in both normal and 

 abnormal yeast. Since yeast cells containing more that 53 per cent of 

 protein usually contain little glycogen, it is probable that yeast cells 

 in potato mashes, etc., will contain little. Bruschi 2 found that 

 antiseptics, such as chloroform, ether, thymol and formalin, did not 

 completely stop the formation of glycogen even though fermentation 

 was impeded. The production of alcohol determined the amount of 

 glycogen formed. It is stated that glycogen is formed by the con- 

 densation of some intermediate product of fermentation. Kullberg 3 

 reported an inverse relation between the nitrogen content of the yeast 

 cell and the glycogen content. 



Will and Heuse 4 found that ethylacetate satisfied the carbon 

 requirements of yeast and that they could grow without the presence 

 of organic matter. Lindner and Cziser 6 found alcohol a source of 



carbon. Stockhausen 6 confirmed this opinion. Lindner 7 has re- 



i 



1 Henneberg, W. Amount of glycogen in differently fed yeast cultures. Bieder- 

 mann's Zentr. 1912. 277-8; Chem. Absts. 6, 1917-18. 1912. 



2 Bruschi, D. Formation of glycogen in the yeast cell. Att. accad. Lincei, 

 21, I, 54-60; Chem. Absts. 6, 1018-19, 1912; Cent. Bakt. Abt. II, 35, 316; Chem. 

 Absts. 7 (1913) 495. 



3 Kullberg, S. Simultaneous change in the content of glycogen, nitrogen 

 and enzyme in living yeast. Zeit. physiol. Chem. 92, 340-359. (1914); Chem. 

 Absts. 9 (1915), 471. 



4 Will, H., and Heuse, R. Ethyl acetate as a source of carbon for yeasts 

 and other budding fungi. Zeit. ges. Brauw. 35, 128-9, Chem. Absts. 6 (1912) 

 1626. 



5 Lindner, P. and Cziser. Alcohol, a more or less excellent nutrient medium 

 for different organisms. Wochenschr. Brau. 29, 1-6; Chem. Absts. 6 (1912) 1916. 



6 Stockhausen, F. Alcohol assimilation by yeasts. Chem. Ztg. 35, 1197. 

 Chem. Absts. 6 (1912) 3106. 



7 Lindner, P. Non-assimilation of methyl alcohol by microorganisms capable 

 of assimilating ethyl alcohol. 2. Spiritusind. 35, 185; Chem. Absts. 6 (1912) 1917. 



