DNA nucleobase properties and photoreactivity: Modeling environmental effects

Roca-Sanjuán, Daniel; Olaso-González, Gloria; Rubio, Mercedes; Coto, Pedro B.; Merchán, Manuela; Ferré, Nicolas; Ludwig, Valdemir; Serrano-Andrés, Luis

doi:10.1351/PAC-CON-08-08-30

Pure Appl. Chem., 2009, Vol. 81, No. 4, pp. 743-754

http://dx.doi.org/10.1351/PAC-CON-08-08-30

DNA nucleobase properties and photoreactivity: Modeling environmental effects

Daniel Roca-Sanjuán¹, Gloria Olaso-González¹, Mercedes Rubio¹, Pedro B. Coto¹, Manuela Merchán¹, Nicolas Ferré², Valdemir Ludwig³ and Luis Serrano-Andrés¹

¹ Institute of Molecular Science, University of València, Apartado de Correos 22085, ES-46071 València, Spain
² Universités d'Aix-Marseille I, II et III-CNRS, UMR 6264: Laboratoire Chimie Provence, Theoretical Chemistry, F-13397 Marseille Cedex 20, France
³ Department of Physics, Universidade Federal do Mato Grosso do Sul CP 549, CEP 79070-900, Campo Grande, MS, Brazil

Abstract: The accurate ab initio quantum chemical (QM) method multiconfigurational second-order perturbation (CASSPT2)/complete active space self-consistent field (CASSCF) has been used in conjunction with molecular mechanics (MM) procedures to compute molecular properties and photoinduced reactivity of DNA/RNA nucleobases (NABs) in isolation and within a realistic environment, in which the double helix strand, the aqueous media, and the external counterions are included. It is illustrated that the use of an MM model is helpful both to account for short- and long-range effects of the system surrounding the QM molecular core and to provide the proper structural constraints that allow more accurate QM geometry determinations.