90 BIOLOGY OF PNEUMOCOCCUS 



magglutinative action of some vegetable proteins, especially the 

 globulins and the proteoses of beans. 



Mair, 856 differing from Julianelle and Reimann, believed that the 

 purpura-producing principle was an intracellular substance and 

 that the cell must be disintegrated by autolysis or other means be- 

 fore the active substance could be absorbed in sufficient amount to 

 produce purpura. Another difference reported by Mair was the ac- 

 celerating action of the pure bile-salts, sodium desoxycholate or 

 sodium choleate, in releasing the purpurigenic principle. By run- 

 ning parallel experiments with untreated pneumococcal suspen- 

 sions, some bile-treated and others containing sodium desoxycho- 

 late, Mair obtained equally good reactions. He inferred from his 

 experiments that: 



It may be that solution of the bacterial bodies is all that is required, 

 a preformed constituent of the cell thus being set free and rendered 

 capable of absorption from the peritoneal cavity of the mouse. On the 

 other hand, the delayed reactions obtained with pneumococci which had 

 been subject only to slight autolysis, and with pneumococci dissolved 

 in bile and immediately heated, suggest the possibility that proteolytic 

 changes which may occur in the body of the mouse are required for the 

 development of the substance. 



Moreover, Mair found that mice varied in susceptibility to the 

 purpura-producing substance or, perhaps, in their ability to effect 

 proteolytic changes in the substance. By selecting for breeding 

 mice that were sensitive to the purpura reaction, Mair discovered 

 that this trait was hereditary, and developed a strain of mice with 

 increased susceptibility. 



That the purpura-producing principle might be associated with 

 the carbohydrate constituents of Pneumococcus was claimed by 

 Wadsworth and Brown 1468 and by Sickles and Shaw. 1283 The injec- 

 tion of the cellular carbohydrate intravenously, intraperitoneally, 

 or subcutaneously into mice induced a purpuric condition. Not- 

 withstanding these observations, there is a reason to believe that 

 the effects are ascribable to small amounts of degraded protein in 



