Pneumococcus 



543 



271 (2231) 



The nitrogen content of the pneumococcus: A preliminary report. 



By FRANZ LEINEWEBER, RUTH KAUTSKY, and L. W. FAMULENER. 



[From the Pathological Laboratory, St. Luke's Hospital, 

 New York City.] 



A study of the nitrogen content of various bacterial groups 

 and subgroups was undertaken by the writers some months ago. 

 The object was to determine, if possible, the relationship of the 

 nitrogen content which might occur between members of a single 

 group, and also that between the subgroups of a species where 

 such are known to exist. While progress has been made in this 

 study, much remains to be done, and we are continuing the in- 

 vestigation. A preliminary report of the results of our analyses 

 made upon the pneumococcus, including the four serological sub- 

 groups, may prove to be of interest to others. We therefore 

 submit some of the data, although the study is not completed. 



Recognizing the many known factors which may enter and 

 alter the results in a study of the protein content of bacteria, we 

 have attempted to control these factors in so far as possible by 

 keeping them constant throughout. In this way, to a certain 

 degree, a comparison is possible between the derived chemical 

 data. 



The organisms used in this study were for the most part re- 

 covered from sputum, blood, etc., of patients in St. Luke's Hos- 

 pital, although we are indebted to Dr. Avery, of the Rockefeller 

 Institute, and to Dr. Wads worth, of the New York State Health 

 Department Laboratories, for a few strains of the Type II. In 

 each instance the identity of the organism was established by its 

 characteristic morphology, staining properties, bile solubility, 

 and reaction to specific immune serum. Ten strains of each ot 

 the four chief groups were cultured in flasks containing about 

 75 c.c. of a beef infusion broth containing one per cent, of dex- 

 trose, and having an average reaction of P H 7.4 to 7.6. Usually 

 sufficient growth for the purpose of the study was produced 

 within 24 hours, when incubated at 36° or 37° C. The sedi- 

 mented organisms were removed from the bottom of the flask 

 by means of a Pasteur pipette, placed in a Hopkins vaccine tube, 

 centrifuged, and the supernatant fluid removed from above the 



