Density functional theory study of interaction, bonding and affinity of group IIb transition metal cations with nucleic acid bases

作者：Bagchi Sabyasachi; Mandal Debasish; Ghosh Deepanwita; Das Abhijit K^*

来源：Chemical Physics, 2012, 400: 108-117.

DOI：10.1016/j.chemphys.2012.03.003

• Nucleobase
• Tautomerization
• Stability
• Metal ion affinity
• Monocoordination
• Bicoordination

The structure, bonding, and energetics of the complexes obtained from the interaction between the most stable tautomeric forms of free DNA and RNA bases and Zn2+, Cd2+ and Hg2+ cations have been studied using density functional B3LYP method. The 6-311+G (2df, 2p) basis set along with LANL2DZ pseudopotentials for the cations are used in the calculations. The tautomerization paths of the nucleobases are investigated and transition states between the tautomeric forms of the free bases are located. The relative stability of the complexes and the tautomers of the free nucleobases are discussed referring to MIA and relative energy values. For uracil, thymine and adenine, interaction of the metal cations with the most stable tautomers form the least stable molecular complexes. For cytosine and guanine, the stability of the metalated complexes differs significantly. The enthalpy (Delta H), entropy (T Delta S) and free energy (Delta G) of the complexes at 298 K have also been calculated.

• 出版日期2012-5-25