Fig. 3: YchF promotes the dissociation of ribosomal subunits and the helical domain is required for its cellular function.

a Alignment of helical domain (red) between YchF(H114A) obtained in this study and the crystal structure of H.influenzae YchF (PDB: 1JAL). Domains in the two proteins are color-coded and labeled as indicated. b Zones of E. coli growth inhibition by disc diffusion away from H₂O₂. 10 mM (cyan), 200 mM (blue) an 800 mM (red) of H₂O₂ were used for the plates expressing wild-type YchF (middle) and the one truncating helical domain (right). Empty vector was used as control (left). c Relative sizes of the red circles in (b) are quantified as the ratio of (diameter of red circle)/(diameter of plate). Data are presented as mean values ± SD. Experiments were performed in replicates (n = 4). P values were calculated by two-sided t-Test with unpaired two sample for means. EV, empty vector; WT, wild-type; ∆HTH, YchF with α4-α5 coiled coil truncated. Polysome profiling of ∆ychF cells with the treatment of chloramphenicol in the absence (d) or presence of 5 µM YchF (e, f). 2 mM of ATP (e) and AMPNP (f) were added to the lysis buffer. Ratios of 50S and 70S peaks were calculated based on the peak heights. Source data are provided as a Source Data file.