THE INFLUENCE OF CARBOHYDRATE ON THE 

 NITROGEN METABOLISM OF BACTERIA 



NATHAN BERMAN and LEO F. RETTGER 



From the Sheffield Laboratory of Bacteriology and Hygiene, Yale University 

 Received for publication July 3, 1917 



The use of fermentable sugars, alcohols and glucosides in 

 bacteriological culture media has marked a distinct advance in 

 the present methods of studying and classifying bacteria. Chief 

 emphasis has been placed, however, on the question as to whether 

 certain given organisms attack these substances with resultant 

 acid and gas production. Among those who have given their 

 attention to the utilization of carbohydrates and their influence 

 on nitrogen metabolism considerable difference of opinion exists; 

 ,and a review of the literature shows that further and more defi- 

 nite information on this subject is indeed desirable. 



Liborius (188G) observed that the presence of sugar did not 

 prevent liquefaction of gelatin by Bacillus subtilis, Pseudomonas 

 fluorescens and Bacillus pyocyanmis. Winternitz (1892), as the 

 result of animal feeding experiments, came to the conclusion 

 that glucose and lactose inhibit the bacterial decomposition of 

 protein. Glenn (1911) claimed 'that in a medium containing 

 sugar and protein material the carbohydrate is first attacked, 

 and that the protein is subsequently decomposed, providing the 

 acidity produced in the complete fermentation of the sugar is 

 not too great. According to Glenn, therefore, no protein utiliza- 

 tion takes place in the presence of fermentable carbohydrate. 



Kendall, Day and Walker (1913) emphasized the preference 

 of bacteria for sugars. According to them nitrogen metabolism 

 in carbohydrate media is at its minimum. Aubel and Colin 

 (1913) observed that fermentable sugars inhibit color produc- 

 tion of bacteria. A year later these same authors found that 

 the addition of glucose to a medium lessens or inhibits the pro- 



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THE JOURNAL OF B ACTERIOLOGT. VOL. Ill, NO. 4 



