64 THE CHEMISTRY OF BACTERIA 



the same conclusion. The analysis of one hundred grams of dried 

 tubercle bacilli by Ruppel 1 indicates the importance of the nucleins in 

 bacterial proteins. 



Grams. 



Nucleic acid (tuberculinic acid) 8.5 



Nucleoprotamin 25.5 



Nucleoproteid 23.0 



Albuminoids (keratin, etc.) 8.3 



Fat and wax 26 . 5 



Ash 9.2 



Carbohydrates. Glycogen or some similar carbohydrate, which is 

 readily detected by the mahogany color it gives with iodine, is found 

 in many bacteria, as has been stated previously, but it is extremely 

 difficult to decide definitely whether it is limited exclusively to the cell 

 membrane or scattered somewhat diffusely through the cytoplasm 

 as well. 



Fats and Fatty Derivatives. Fats, fatty acids, lipoids and waxes, 

 which may be demonstrated by staining bacteria with Sudan III, 

 Scharlach R, and osmic acid, occur in variable amounts in the tubercle 

 bacillus and other acid-fast bacilli. The amount of these extractives 

 may be very great in the acid-fast group, varying from 26 to 40 per cent, 

 of the total dry residue. Considerable discussion has centred around 

 the distribution of these substances, many authorities claiming that 

 the fats and waxes are contained in the cell wall of the organism, while 

 others maintain that these substances are scattered throughout the 

 cell substance as well. In the acid-fast bacilli it is probable that these 

 fats are both intra- and extracellular, for analyses show that a certain 

 amount of them can be extracted from intact bacilli, while still more 

 can be extracted when the organisms are broken up. The following 

 table from Kresling 2 illustrates the distribution of the fatty substance 

 of the tubercle bacillus: 



I. CONTENTS OF THE DRIED TUBERCLE BACILLI IN THE 

 PREPARATION OF TUBERCULIN. 



Per cent. 



Moisture (dried at 100 -l 10 C.) 3.9375 



Moisture (dried in desiccator) 3 . 08 



Ash 2.55 



Nitrogen - 8.575 



Nitrogen-containing substances (albumin) reckoned by multiply- 

 ing the amount of N by the factor 6.25 (the N of lecithin and 

 other substances soluble in chloroform, benzol, ether, and 



alcohol were not reckoned) 53 . 59 



Fatty substances in medium after the first four determinations 38.95 

 Other N-free substances, reckoned as the difference . . . . . 9725 



1 Loc. cit. 



2 Centralbl. f. Bakteriol., 1901, xxx, 909, 



