FIGURE 6.

Effect of temperature on the formation of D5–D123 complex. (A) NMR HSQC spectral evidence for the formation of a D5–D123 complex in the ribose region. At 25°C, addition of ∼0.22 mM unlabeled D123 to ∼0.2 mM ¹⁵N–¹³C-labeled D5-PL leads to disappearance of most of the D5 resonances. (B) NMR HSQC spectral evidence for the formation of a D5–D123 complex in the base region. At 25°C, addition of ∼0.22 mM unlabeled D123 to ∼0.2 mM ¹⁵N–¹³C-labeled D5-PL leads to disappearance of most of the D5 resonances. (C) NMR HSQC spectrum in the ribose region collected at 45°C leads to recovery of peaks. All the experiments were done on equimolar amounts of sample of ∼0.2 mM each and under identical conditions as in A. (D) NMR HSQC spectrum in the base region collected at 45°C leads to recovery of peaks. All the experiments were done on equimolar amounts of sample of ∼0.2 mM each and under identical conditions as in B.