Advertisement

Thymine-metal ion interactions: relevance for thymine quartet structures

  • Eva Freisinger
  • Arnd Schimanski
  • Bernhard Lippert
Original Article

Abstract

Apart from their function as counter ions for the charge neutralization of nucleic acids, alkali metal ions play important roles in stabilizing particular multistranded nucleic acids, e.g. guanine quartets in telomeres and uracil (U) or thymine (T) quartets. Here X-ray crystal structure determinations of a series of alkali metal ions (Na+, K+, Rb+, Cs+) as well as of Mg2+ and H5O2 + adducts with the model bases 1-methylthymine and 1-ethylthymine are reported, which bear relevance to the question of thymine quartet (T4) geometries. The compounds isolated differ in their stoichiometries (T:M=4:1, 2:1, 1:1), and the ways the metal ions interact with the bases. The two extremes are exclusive metal coordination to exocyclic oxygen atoms of the T bases and exclusive H bonding between M aqua cations and the bases.

Keywords

Alkali metal ions Thymine nucleobases Quartet formation Hydrogen bonding X-ray crystallography 

Abbreviations

1-EtTH

1-ethylthymine

1-MeTH

1-methylthymine

1-MeUH

1-methyluracil

1-PrTH

1-propylthymine

G

guanine

T

thymine

U

uracil

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© SBIC 2001

Authors and Affiliations

  • Eva Freisinger
    • 1
  • Arnd Schimanski
    • 1
  • Bernhard Lippert
    • 1
  1. 1.Fachbereich ChemieUniversität DortmundDortmundGermany

Personalised recommendations