Production of Creatinine by Bacteria. 55 



feces found 28 per cent, of communior, 60 per cent, communis, 4 

 per cent, aerogenes, and 8 per cent, acidi lactici. 



The results of an analysis of thirty-two strains isolated in my 

 laboratory from human feces were as follows: 



Per Cent. 



B. colt communior 65 



B. coli communis 28 



B. aerogenes 3-5 



B. acidi lactici 3-5 



The saccharose fermenting species, then, may predominate in 

 water recently contaminated with human feces. 



40 (736) 



Production of creatinine by bacteria. 



By J. G. Fitzgerald and Carl L. A. Schmidt. 



[From the Hearst Laboratory of Pathology and Bacteriology, 

 University of California, Berkeley, California.] 



Very little work has been done to determine whether creatinine 

 is produced by bacteria growing on media free from creatin and 

 creatinine. German, 1 in a brief review of the literature on this 

 subject, makes mention of only three contributions. In his paper, 

 German gives the result of an investigation of thirty-five species 

 of bacteria to determine whether they were able to produce 

 creatinine. In summing up, he says that this characteristic might 

 be of value in the differentiation of closely allied species. 



Our work was undertaken to ascertain: (1) Whether creatinine 

 production is of any value in the differentiation of groups of 

 closely allied species; (2) to determine the method best suited 

 for studying creatinine production by bacteria; (3) to ascertain 

 what amounts of creatinine were produced so that certain quanti- 

 tative studies might be undertaken. 



A medium composed of 2 per cent. Witte's peptone and .5 per 

 cent, salt furnishes a creatin and creatinine free medium. Twenty- 

 eight strains of bacteria, belonging to the mucosus capsulatus 

 group of microorganisms, including B. rhinoscleromatis, B. ozcence 

 and B. lactis aerogenes, were grown on the above medium for eight 



1 German, Centralbl. f. Bakt., I. Abt. Orig., Bd. 63, Heft 7, 1 June, 1912. 



