Thermal stability studies of the non canonical base pair between 5- methyl-isocytosine and isohypoxanthine

Article abstract of DOI:10.1016/S0040-4020(98)00820-5

The hybridization properties of 5-methyl-isocytosine ((5Me)isoC) and isohypoxanthine (isoI) have been investigated by using ultraviolet melting techniques. These two bases were incorporated into heptadecanucleotides using the phosphoramidite chemistry. The base pair (5Me)isoC/isoI was found to be isoenergetic with the A/T base pair. A small destabilization was observed when isoI was located opposite T or G and can be interpreted by a pairing mode between these bases and isol in its lactam form.