THE MECHANISM OF GRANULAR GROWTH OF RABBIT 

 SEPTICEMIA BACILLUS TYPE G. 



By PAUL H. De KRUIF. 



(From the Laboratories of The Rockefeller Institute for Medical Research, New York.) 



(Received for publication, December 28, 1921.) 



INTRODUCTION. 



It has been stated by Beniasch (1) that the acid flocculation op- 

 timum of bacteria is referable only to the Ch+ and is not influenced 

 by the unionized acid or the anion of the acid. This concept may hold 

 for buffer mixtures made up of certain acids and their sodium salts. 

 But certain buffer mixtures exist which are composed of an acid plus 

 some totally different substance, bearing no close chemical relation- 

 ship to the acid. Examples of such buffer mixtures are glycocoll- 

 HCl and glycocoll-Na acetate-NaH2P04-HCl. These have been 

 found by the writer (2) to be very useful in acid agglutination studies. 

 It is important to learn whether such buffer substances exert an effect 

 on the acid agglutination point of bacteria, which might differ from 

 the values found for the JVIichaelis (3) series, 



EXPERIMENTAL. 



The Na lactate-lactic acid buffer series of Michaelis (3) covers a 

 range from pH 4.7 to 2.4. It was desired to test the behavior of 

 distilled water suspensions of Microbe G and D in higher Ch+. 

 Since this range was not covered by the Na lactate-lactic acid series, 

 recourse was had to the glycocoU-HCl series of Sorensen (4), which 

 covers a range from pH 3.0 to pH 1.2. This buffer series was prepared 

 from the Sorensen chart. 



The pH of these mixtures was tested colorimctrically and checked 

 by the potentiometer. 



The flocculating activity of this buffer series was then compared 

 to that of the Na lactate-lactic acid scries. The technique of the 



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