Figure 9.

(a) Structure of the modified nucleotide-containing DNA oligomer, d[5′-T₁A₂^phG₃G₄T₅A₆-3′]·d[3′-A₁₂T₁₁C₁₀C₉A₈T₇-5′], where a phenyl group is attached to G₃. The DNA sequence is the sequence of the six base pairs around the phenylated guanine in the experiment.(18) (b) The effect of the phenyl group attachment on the IP of the DNA oligomer in the gas phase, in the neutral state in water, and in the ionic state in water, for the 55th fiber model structure and the 4th fiber model structure, as indicated. The IPs before and after a phenyl group is attached are indicated by G and ^phG, respectively.