BOLTON, HOYER, AND RITTER 



21 



TS 



EDTA 



JJLJ 



6 mm 60,000 RPM 



Fig. 3. Effect of EDTA on the sedi- 

 mentation diagrams of E. coli juice. The 

 two lower diagrams are from preparations 

 containing one-half as much material as 

 those for the upper pattern. 



6 min 60,000 RPM 



Fig. 4. Effect of nucleases on sedimenta- 

 tion diagrams. The lower pattern is from a, 

 preparation one-half as concentrated as that 

 of the upper diagram. 



eluded that the bulk of the high-molecular-weight components of E. coli is 

 composed of ribonucleoproteins held together in a fashion in which divalent 

 cation (s) (probably Mg ++ ) and the integrity of ribonucleic acid play important 

 roles. Thus, in certain physical and chemical attributes the "ribosomes" (ribo- 

 nucleoprotein particles) of E. coli resemble constitutive elements of the cyto- 

 plasm of other bacteria, and also of yeast, plants, and mammals. 



