Binding of metal ions and water molecules to nucleic bases

Abstract

Hydrogen bond interactions between nucleic bases and water have been analyzed by surveying Protein Data Bank (PDB) and quantum chemical calculations, for the noncoordinated and coordinated water molecule. Python homemade script was used for the PDB search and Gaussian09 program was used for the calculations of interaction energy at MP2/def2-QZVP level on model systems. The results from PDB survey and from the calculations are in agreement: hydrogen bonds are shorter and stronger when water is bonded to a metal ion.