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Multiple structures for the 2-aminopurine (2AP)-cytosine mispair have been studied using NMR, UV, and fluorescence. It has been shown that an equilibrium between the neutral wobble and the protonated Watson-Crick structures exists. The relative contributions of these configurations to 2AP-induced transition mutations is considered. The base pair of 2AP and cytosine is intermediate in transition mutations 2AP generates.

Research has been conducted on the ring fragmentation thymine product N-(2-deoxy-beta-D-erythro-pentofuranosyl)formamide residue. The use of the one- and two-dimensional NMR spectroscopy is described.

Nuclear magnetic resonance studies and molecular dynamics calculations were used to determine the structure and dynamics of nicked and gapped oligonucleotides consisting of 14 base pairs. Results show that the nicked DNA can exhibit a B-form conformation with better local flexibility or a kinked conformation that minimizes the gap. The results of this study have important bearing on DNA repair efficiency and other interactions dependent on effective DNA repair.

Two mismatches, G*G and I*I, are inserted at the central position of 5'd-(GCCACXAGCTC)*d(GAGCTXGTGGC) to conduct NMR and molecular dynamics investigations. These duplexes form the sequence 29-39 of the K-ras gene coding for the glycine 12. NMR spectra indicate that the duplexes are not greatly distorted by the insertion of the mismatches and their global conformation is that of a canonical B-form double helix.