Photochemical selectivity in guanine–cytosine base-pair structures
- 23 December 2004
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 102 (1) , 20-23
- https://doi.org/10.1073/pnas.0408574102
Abstract
Prebiotic chemistry presumably took place before formation of an oxygen-rich atmosphere and thus under conditions of intense short wavelength UV irradiation. Therefore, the UV photochemical stability of the molecular building blocks of life may have been an important selective factor in determining the eventual chemical makeup of critical biomolecules. To investigate the role of UV irradiation in base-pairing we have studied guanine (G) and cytosine (C) base pairs in the absence of the RNA backbone. We distinguished base-pair structures by IR-UV hole-burning spectroscopy as well as by high-level correlated ab initio calculations. The Watson-Crick structure exhibits broad UV absorption, in stark contrast to other GC structures and other base-pair structures. This broad absorption may be explained by a rapid internal conversion that makes this specific base pair arrangement uniquely photochemically stable.Keywords
This publication has 25 references indexed in Scilit:
- Conformers of Guanosines and their Vibrations in the Electronic Ground and Excited States, as Revealed by Double‐Resonance Spectroscopy and Ab Initio CalculationsChemphyschem, 2004
- Photophysics of Methyl-Substituted Uracils and Thymines and Their Water Complexes in the Gas PhaseThe Journal of Physical Chemistry A, 2004
- Selective photostabilisation of guanine by methylationElectronic supplementary information (ESI) available: Figs. 2 and 3 in colour. See http://www.rsc.org/suppdata/cp/b3/b309031k/Physical Chemistry Chemical Physics, 2003
- Publisher’s Note: “Mechanism for ultrafast internal conversion of adenine” [J. Chem. Phys. 118, 6717 (2003)]The Journal of Chemical Physics, 2003
- Tautomer contributions to the near UV spectrum of guanine: towards a refined picture for the spectroscopy of purine moleculesThe European Physical Journal D, 2002
- Tautomerism of the DNA Base Guanine and Its Methylated Derivatives as Studied by Gas-Phase Infrared and Ultraviolet SpectroscopyThe Journal of Physical Chemistry A, 2002
- Pairing of the nucleobase guanine studied by IR–UV double-resonance spectroscopy and ab initio calculationsPhysical Chemistry Chemical Physics, 2002
- Potential Energy and Free Energy Surfaces of All Ten Canonical and Methylated Nucleic Acid Base Pairs: Molecular Dynamics and Quantum Chemical ab Initio StudiesThe Journal of Physical Chemistry B, 2001
- A Theoretical Investigation of the Physical Reason for the Very Different Luminescence Properties of the Two Isomers Adenine and 2-AminopurineThe Journal of Physical Chemistry A, 1998
- Fluorescence of the Purine and Pyrimidine Bases of the Nucleic Acids in Neutral Aqueous Solution at 300°KScience, 1971