Fig. 4. Effect of RatA on the polysome profile in vitro.

70 pmol of 70S ribosomes were incubated in the buffer S at 30°C for 10 min, then different amount of RatA or IF3 was added, the mixture was incubated for another 10 min, then the concentration of Mg²⁺ was raised to 6 mM and the reaction mixture were further incubated for 10 min before loading to a 5%–40% sucrose density gradient in buffer T following ultracentrifugation and the sedimentation behavior was monitored with the spectrophotometer. (A) Ribosome profile in the presence of 1 mM Mg²⁺ using a 5%–40% sucrose density gradient in buffer S. (B) Ribosome profile in the presence of 6 mM Mg²⁺. (C) Ribosome profile in the presence of 6 mM Mg²⁺ and 10 μg BSA. (D) Ribosome profile in the presence of 6 mM Mg²⁺ and 0.1 μg RatA. (E) Ribosome profile in the presence of 6 mM Mg²⁺ and 0.4 μg RatA. (F) Ribosome profile in the presence of 6 mM Mg²⁺ and 1.25 μg RatA. (G) Ribosome profile in the presence of 6 mM Mg²⁺ and 0.06 μg IF3. (H) Ribosome profile in the presence of 6 mM Mg²⁺ and 0.25 μg IF3. (I) Ribosome profile in the presence of 6 mM Mg²⁺ and 1 μg IF3.