80 



MICROSOMAL PARTICLES 



(«) 



(c) 



Fig. 4. Sedimentation photographs of isolated 80 S particles taken at 0, 2, and 4 minutes 

 after UTS at 200,0C% in the analytical ultracentrifuge. Particles moving from left to 

 right, (a) 80 S particles from 24-hour stationary-phase cells observed immediately after 

 isolation, (b) 80 S particles, isolated from 24-hour stationary cells, suspended in phosphate 

 buffer and kept at room temperature for 2 days, (c) 80 S particles isolated from cells 

 nitrogen-starved for 72 hours suspended in phosphate buffer and kept at room temperature 

 for 2 days. 



