Structural changes of nucleic acid base in aqueous solution as observed in X-ray absorption near edge structure (XANES)

- XANES for adenine nucleotides in aqueous solutions at N K-edge are measured.
- XANES spectra showed pH value dependence.
- The pH value dependence is explained as due to protonation of N1 atom in adenine.
- This explanation is consistent with the published results for gas phase adenine.