FIG 1.

Modified nucleosides in the E. coli ribosome (PDB 5AFI). Pseudouridines (cyan) and methylations (magenta) are clustered around the decoding site (DC), peptidyltransferase center (PTC), and tRNA binding sites (P-site tRNA in green). The mRNA is depicted in yellow. The Ψ modifications, with the relevant PUS responsible for the isomerization(s) in parentheses, are as follows: 16S rRNA, Ψ516 (RsuA); 23S rRNA, Ψ746 (RluA), Ψ2605 (RluB), Ψ955, Ψ2504, Ψ2580 (RluC), Ψ1911, Ψ1915, Ψ1917 (RluD), Ψ2557 (RluE), and Ψ2604 (RluF).