Fig. 8. Factors that dictate the fitness cost of bacteria hosting resistance rRNA methyltransferase genes. (A) Locations of E. coli housekeeping methylations in h44 impacted by adjacent resistance modifications at G1405 and A1408. (B) The exiting nascent peptide does not interact with either A2062 or A2503 when the tunnel is clear. The A2503 base changes conformation to relay nascent peptide information from the NPET to the PTC when the channel is blocked by erythromycin (Ery). (C) Ribosome-erythromycin-ErmCL complex stalling at ermCL triggers the mRNA to release a second ribosome binding sequence (SD2). Created with https://BioRender.com.