Fig. S3.
ATP and GDP do not promote the ribosome dissociation activity of HflX. (A) Malachite green ATPase assay showing ∼80% reduction of ATP hydrolysis in the HflXS219N and HflXT239A mutants. Hydrolysis was measured by quantitating the liberated inorganic phosphate (Pi) using a Pi standard curve. Each reaction contains 4 μM HflX proteins and 0.4 mM ATP. Error bars are SEs of three independent replicates. (B) Ribosome profiles of 100S disassembly reactions in the presence of 2 mM GTP or ATP. Ribosome species were analyzed by 5–25% sucrose gradient sedimentation (x axis). Y axes show absorbance at 254 nm. The blue arrow marks the location of diminishing 100S ribosome with the addition of GTP. (C) Same as in B, except that 2 mM GDP was used in place of ATP or GTP.