High level quantum chemical calculations have been applied to investigate the geometry and electronic properties of the arsenate analogue of the DNA backbone (1). The optimized geometries as well as hyperconjugation effects along the C3‘-O3‘-X-O5‘-C5‘ linkage (X=P,As) exhibit a remarkable similarity for both arsenates and phosphates. This suggests that arsenates – if present – might serve as a potential substitute for phosphates in the DNA-backbone.

On the other hand, our calculations predict that neither steric hindrance nor less polar solvent medium is able to reduce the otherwise high hydrolysis rate of arsenate-esters (2). These results question the stability of As-DNA not only in aqueous but also in non-aqueous environments.

References

1. A. Mladek, J. Sponer, B. G. Sumpter, M. Fuentes-Cabrera, J. E. Sponer. J Phys Chem Lett., In press., http://pubs.acs.org/doi/full/10.1021/jz200015n
2. A. Mladek, J. Sponer, B. G. Sumpter, M. Fuentes-Cabrera, J. E. Sponer. Submitted.