Figure 2.
(A) 2D [13C, 1H] HSQC spectra (54) acquired for A2-DNA (green), A2-DNAm1A16 (orange), A6-DNA (red) and A6-DNAm1A16 (blue) depicting the chemical shift perturbations in the C1΄-H1΄ region. Residues that remain unperturbed are labeled in black; colored labels are for the respective samples and exchange broadened resonances are indicated with an asterisk (*). (B) Chemical shift perturbations observed for sugar (circle) C1΄-H1΄ (blue), C2΄-H2΄/H2″ (red), C4΄-H4΄ (green), base (triangle) C6-H6/C8-H8 (black), N1-H1/C2-H2/N3-H3/C5-H5 (purple) and with backbone (P) 31P resonances in A2- and A6-DNA upon incorporation of m1A16 residue is shown. Residues that exhibit exchange broadening are indicated as open alphabets. (C) 2D [31P, 1H] HSQC (55) acquired for A2-, A6-DNA and their m1A16 counterparts are shown. Phosphorus atom shared between the residues ‘i’ and ‘j’ is given the label jP i.e. T9P indicates T8pT9. (D) Chemical shift perturbation quantitatively plotted as Δωresidue (see ‘Materials and Methods’ section) as a function of DNA sequence for A2- (orange) and A6-DNAm1A16 (blue). (E) Normalized resonance intensities (see ‘Materials and Methods’ section) measured in sugar C1΄-H1΄ (left) and base C6-H6/C8-H8 2D heteronuclear spectra for A2-DNA (green), A2-DNAm1A16 (orange), A6-DNA (red) and A6-DNAm1A16 (blue) as a function of residues, with regions highlighted in gray showing significant intensity perturbation.