622 THE PYOGENIC STAPHYLOCOCCI 



7. Similar conditions, but with maltose. 



8. With glycerin. 



9. With mannite. 



[Though the experiments were not sufficiently extensive to allow of a 

 classification of staphylococci they show quite clearly that the generally 

 accepted grouping into three types depending upon the colour of the growth, 

 on an agar medium is insufficient.] 



3. Toxin. 



In cultures the staphylococcus produces fatty acids from sugars : it con- 

 verts lactose into lactic acid and under certain conditions produces acetic, 

 valerianic, butyric and propionic acids. Cultures also soon give off a musty 

 smell if kept. 



Staphylococci produce a little indol. The property of liquefying gelatin 

 is due to the elaboration of diastases which also peptonize the white of egg. 

 The cultures also contain soluble toxins. 



I. De Christmas filtered a broth culture of the Staphylococcus aureus through 

 a Chamberland bougie and precipitated the filtrate with 4 or 5 volumes of 

 strong alcohol. The precipitate was poured on to a filter paper, washed 

 with alcohol and dissolved with water. The solution thus obtained has 

 some power of producing inflammation, and injected into the anterior chamber 

 of the eye of a rabbit sets up a slight degree of suppuration. 



II. Leber extracted from cultures a crystallizable substance soluble in 

 alcohol, which has marked properties of producing inflammation, suppura- 

 tion and even necrosis of the tissues into which it is injected. Leber calls 

 this substance Pklogosine. 



III. Rodet and Courmont investigated the toxic products of the Staphylo- 

 coccus pyogenes more thoroughly. 



(a) Broth cultures incubated for 20 days at 35 C. were heated for 24 hours 

 at 55 C. to kill the micro-organisms and then filtered through paper. The 

 filtrate was feebly toxic for dogs and rabbits. 



In dogs symptoms of poisoning were seen after the inoculation of 1 -3 c.c. per kg. 

 of body weight, but death only occurred rapidly (at the earliest in 17 hours) on the 

 inoculation of a formidable dose (35 c.c. per kg.) into the jugular vein. Under these 

 conditions it produced a fall of temperature, sickness, convulsions and tremors and 

 tended to stop the heart and respiration. 



Rabbits are still less susceptible. A rabbit weighing 1900 grams inoculated with 

 10 c.c. of heated culture only died at the end of 6 days after having lost flesh and 

 weight. 



The toxin is very unstable and rapidly loses its properties on keeping. 



(6) A culture 20 days old filtered through a Chamberland bougie is even 

 less toxic. After the inoculation of doses as large as 10 and 15 c.c. into the 

 veins of rabbits weighing 2 kg. the animals only showed a transitory rise 

 of temperature without any loss of weight. 



(c) Cultures 20 days old were decanted and the clear liquid filtered. through 

 several folds of paper. The filtrate was precipitated with four times its 

 weight of strong alcohol, and the precipitate washed with alcohol, dried and 

 dissolved in water. 



1. The extract so obtained was only slightly toxic. 



To kill a dog weighing 6 kg. in 2 hours it was necessary to inject into the veins a 

 quantity corresponding to 260 c.c. of culture. The symptoms were dyspnoea, 

 Cheyne-Stokes' breathing, sub-normal temperature, tremors, convulsions and 

 spasms. 



The rabbit is more resistant: it does not succumb to doses corresponding to 



