62 THE CHEMISTRY OF BACTERIA 
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 Kreslingi 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 multiplying 
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 nitrogen-free substances, reckoned as the difference . . . 9725 
II. FATTY SUBSTANCE OBTAINED BY EXTRACTION WITH 
CHLOROFORM, POSSESSES THE FOLLOWING 
CHARACTERISTICS: 
Melting-point 46° C. 
Acid number 23 . 08 
Reichert-Meissel number 2 . 007 
Hehner number 74 . 236 
Saponification number ■. .60.70 
Ether number 36 . 63 
Iodine number (according to Hiibl) 9.92 
III. THE FATTY SUBSTANCE OBTAINED BY EXTRACTION WITH 
CHLOROFORM CONTAINS: 
Per cent. 
Free fatty acids 14.38 
Neutral fats and esters of fatty acids 77 . 25 
Alcohols separated from the fatty acid esters (with melting-point 
43.5-44° C.) 39.10 
Lecithin 0.16 
Cholesterin Not determined 
Substances directly soluble in water . 73 
Substances soluble in water which are formed by the complete sapon- 
ification of the fatty substances 25 . 764 
Inorganic Constituents.— The most conspicuous inorganic element 
found in the ash of bacteria is phosphorus, and the content of phos- 
phorus, recovered as phosphoric acid, frequently reaches as high as one- 
half the total ash weight. It is probable that a considerable part of 
this phosphorus is combined with nucleic acid to form nucleo-protein. 
4. Spores.— The chemical composition of spores is not well deter- 
mined, but the generally accepted theory is that they contain rela- 
1 Centralbl. f. Bakteriol., 1901, 30, 897. ■ 
