Differential solvation and tautomer stability of a model base pair within the minor and major grooves of DNA

F.-Y. Dupradeau, D.A. Case, C. Yu, R. Jimenez, F.E. Romesberg, J. Am. Chem. Soc. (2005) 127:15612-15617.
pubpic2005dupradeauWe show that when HBO is positioned in the minor groove of DNA, the enol tautomer of HBO is preferentially stabilized, whereas our previous study showed that when HBO is positioned in the major groove, the keto tautomer is preferentially stabilized. Based on MD simulations, we suggest that this results from the formation of a stable hydrogen-bond between the HBO enol and an H-bond acceptor that is only available in the minor groove.