VII. SYNTHESIS OF RNA AND RIBOSOMES 



339 



20 - 



10 - 



(C) 



IO"'*M Mg SN 



i>W-^^^ 



20 



Froction number 



30 



Fig. 29. Purification of the eosome fraction. 70S ribosomes were prepared liy 

 centrifugation from E. coli given 2 minutes' exposure to P^'Oi . A portion was 

 analyzed on DEAE (a). Another portion was suspended in buffer with a magnesium 

 concentration of 10"' M and centrifuged 40K 240 minutes. The pellet (6) and 

 supernatant fluid (c) were then analyzed on DEAE. Note that the bulk of the 

 material is sedimented but the bulk of the ?'" remains in the supernatant fluid. 



