Spatial arrangement of functional domains in OxyS stress response sRNA

NMR characterization of 110 nt OxyS RNA. The color codes follow the colors used in the studies of individual stem–loops. (A) Imino–imino region of JR-NOESY spectrum (τ_m = 200 msec) with traced imino–imino contacts, acquired at 5°C. (B) ¹H–¹⁵N HNN-COSY spectrum acquired at 5°C. Resonances of donor and acceptor nitrogens involved in hydrogen bonds, specifically G(N1)-C(N3) and U(N3)-A(N1), are connected with dashed gray lines. (C) NMR-derived secondary structure of OxyS. Spectra were acquired at 1 mM RNA concentrations, 15 mM Na-phosphate buffer, 30 mM NaCl, and pH 6 in 90% H₂O and 10% ²H₂O on a 600 MHz NMR spectrometer.