BIOLOGICAL ORDER 



-^Antibodies agoinst 

 type m 



sm 



Rin 



sn 



TH 



Antibodies against 

 typell 



sm 



RE 



SE 



TE 



Transformed (T)II 



Figure 3. Transformation of Fneu?no coccus and the Transforming 

 Principle. 



The smooth (S) Pneumococcus type III gives oflF rough (R) mutants devoid 

 of capsule, that is, of the specific polysaccharide characteristic of the type. 

 The smooth Pneumococcus type II also gives off rough mutants. The DNA 

 extracted from type III transforms the rough, originally II, into a smooth 

 bacterium possessing the polysaccharide of type III. 



The antibodies against type III agglutinate the smooth III and the trans- 

 formed II but not the rough strains III and II. 



The antibodies against type II agglutinate the smooth II but not the smooth 

 III, the rough II, and the transformed II. 



[18] 



