Spatial arrangement of functional domains in OxyS stress response sRNA

Interaction of OxyS with CDS and RBS regions of fhlA. (A) Imino region of 1D ¹H spectra of SL1_Δ17, fhlA1, and their equimolar mixture. Six new imino signals originating from the interaction are colored in magenta and orange. (B) Imino region of 1D ¹H spectra of SL3, fhlA41 and their equimolar mixture. Four new imino signals originating from the interaction are colored in green and blue. Spectra were acquired at 25°C, 15 mM Na-phosphate buffer, 30 mM NaCl, 5 mM MgCl₂, and pH 6 in with 90% H₂O and 10% ²H₂O on a 600 MHz NMR spectrometer. RNA concentrations varied from 0.5 to 1.25 mM for SL1_Δ17, fhlA1, SL3, and fhlA41, whereas it was set to 0.2 mM per strand for the mixtures. (C) Secondary structure representation of fhlA1–SL1_Δ17 complex. Nucleotides involved in intermolecular base-pairing are colored in magenta and orange. (D) Secondary structure representation of fhlA41–SL3 complex. Nucleotides involved in intermolecular base-pairing are colored in green and blue. (E) Schematic of the bipartite OxyS–fhlA interaction.