Pierce, S.; Wang, J.; Jayawickramarajah, J.; Hamilton, A.; Brodbelt, J. Examination of the Effect of the Annealing Cation on Higher Order Structures Containing Guanine or Isoguanine Repeats. Chemistry - A European Journal 2009, 15, 11244-11255.
Abstract
Pentaplex oligonucleotides: Oligonucleotide strands containing repeats of isoguanine bases are studied by mass spectrometry and circular dichroism in the presence of various cations. Isoguanine strands tend to form five-stranded structures surrounding central cations (as can be seen with isoguanine bases shown in the figure), which are similar to guanine quadruplexes observed in vivo. With some cations, however, isoguanine quadruplexes were also formed.
