title: A novel conception for spontaneous transversions caused by homo-pyrimidine DNA mismatches: a QM/QTAIM highlight.
abstract: We have firstly shown that the T·T(w) and C·C(w) DNA mismatches with wobble (w) geometry stay in slow tautomeric equilibrium with short T·T*(WC) and C·C*(WC) Watson-Crick (WC) mispairs. These non-dissociative tautomeric rearrangements are controlled by the plane-symmetric, highly stable, highly polar and zwitterionic transition states. The obtained results allow us to understand in what way the T·T(w) and C·C(w) mismatches acquire enzymatically competent T·T*(WC) and C·C*(WC) conformations directly in the hydrophobic recognition pocket of a high-fidelity DNA-polymerase, thereby producing thermodynamically non-equilibrium spontaneous transversions. The simplest numerical estimation of the frequency ratio of the TT to CC spontaneous transversions satisfactorily agrees with experimental data.
authors.affiliation: Department of Molecular and Quantum Biophysics, Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Akademika Zabolotnoho Str., 03680 Kyiv, Ukraine. dhovorun@imbg.org.ua.
authors.forename: Ol'ha O
authors.initials: OO
authors.lastname: Brovarets'
authors.forename: Dmytro M
authors.initials: DM
authors.lastname: Hovorun
mesh_terms: D020137:Base Pair Mismatch; D003596:Cytosine / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D006860:Hydrogen Bonding; D011743:Pyrimidines / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics; D013941:Thymine / Q000737:chemistry
chemical_list: D011743:Pyrimidines; D003596:Cytosine; D004247:DNA; C030986:pyrimidine; D013941:Thymine