500 CURRENT PROBLEMS ON YEASTS 



this substance was 223° C. Experimental data showed that this crystalline bios lacked anti- 

 neuritic power and was probably different from vitamin B, but they were not decided whether 

 it was entirely without effect on mammalian growth. 



Two years later Kerr, Eddy, and Williams' published confirmation of their earlier report. 

 They were more concerned in this report, however, in showing that the accessory properties 

 of their "Bios 223" were inherent m the crystals and not due to impurities which adhered to 

 the crystals. They experienced complete inactivation of Bios 223 by forming the crystalline 

 benzene sulphonamide and a recovery of the activity by hydrolyzing this inactive crystalline 

 product. This seemed to convince these authors that the activity of Bios 223 was inherent 

 in the crystals. From the nature of the addition compound it was suggested that the — NH2 

 group was concerned with the exercise of the accelerating function since the activity was lost 

 when this group was replaced by benzene-sulphon chloride. 



The work of Lucas, Miller, and others at the University of Toronto has also been 

 continued by Eastcott, Whiteman, and Sims. Eastcott' hypothecated the existence 

 of inactive "biogens" from which the active bios was formed. The biogens were not 

 isolated. She further postulated the existence of biogenases to explain the irregular 

 behavior of the bioses observed in the production of yeast under controlled experi- 

 mental conditions. Sims^ studied the effect of certain chemical treatments of the 

 bios on its activity. Whiteman"" made the interesting statement that a limited de- 

 velopment of yeast took place without bios and even without salts or sugar. She as- 

 sumed that a certain quantity of bios existed in the yeast cell itself. 



Zajdel and Funk,^ using six species of yeasts propagated from single cells, reit- 

 erated the need for vitamin D (bios). They found that reproduction decreased ac- 

 cordingly as the cane sugar was purified, and ceased when the cane sugar was finally 

 purified. Absence of bios resulted in a diminution of granules in the cells. One species, 

 a bakers' yeast, however, grew in the absence of bios, giving always just a little less 

 growth than the culture propagated in the presence of bios. In order to explain this 

 anomaly, Zajdel and Funk suggested that the culture was contaminated or that a wild 

 yeast had been isolated in place of the bakers' yeast. Realizing these possibilities, 

 why did they not find out the true nature of the culture? Why did they not determine 

 whether their cultures were contaminated? It has been noticed by others that differ- 

 ent species of yeasts react differently toward bios. However, they concluded that wild 

 yeasts can synthesize bios while cultivated species cannot. What are the criteria with 

 which to decide whether a strain is a wild or cultivated yeast? Might there not be 

 intermediate strains which would react irregularly to bios if it has any relation to 

 multiplication? Zajdel and Funk's statement is either an explanation of the present 

 chaotic condition of the bios question or a convenient refuge for anomalous data. 



Tanner, Devereux, and Higgins'' called attention to a number of points which 

 seem to have been overlooked by certain other workers. They stated that many 

 different definitions of the term "growth" have been used by those working in this 



' Kerr, R. W., Eddy, W. H., and Williams, R. R.: Proc. Soc. Exper. Biol. 6- Med., 23, 416-19- 

 1926. 



^Eastcott, Edna V.: Tr. Roy. Soc. Canada, Sec. Ill, 19, 21-24. 1925. 



i Sims, H. des B.: ibid., 18, 116. 1924. ■•Whiteman, D.: ibid., 19, 24-25. 1925. 



5 Zajdel, R., and Funk, C: Coinpl. rend. Soc. de bioL, 92, 1527-28. 1925. 



* Tanner, F. W., Devereux, E. D., and Higgins, F. M.: J. Bad., 11, 45-64. 1926. 



