Long-wavelength fluorescence from 2-aminopurine-nucleobase dimers in DNA

Eleanor Y. M. Bonnist, Anita C. Jones

Research output: Contribution to journalArticlepeer-review

Abstract

When 2-aminopurine (2AP) is substituted for adenine in DNA, it is widely accepted that its fluorescence spectrum is essentially unchanged from that of the free fluorophore. We show that 2AP in DNA exhibits long-wavelength emission and excitation bonds, in addition to the familiar short-wavelength spectra, as a result of formation of a ground-state heterodimer with an adjacent, pi-stacked, natural base. The observation of dual emission from 2AP in a variety of oligodeoxynucleotide duplexes and single strands demonstrates the generality of this phenomenon. The photophysical and conformational properties of the long-wavelength-emitting 2AP-nucleobase dimer ore examined. Analogous long-wavelength fluorescence is seen when 2AP π-stacks with aromatic amino acid sidechains in the active sites of methyltransferase enzymes during DNA nucleotide flipping.

Original languageEnglish
Pages (from-to)1121-1129
Number of pages9
JournalChemPhysChem
Volume9
Issue number8
Early online date30 Apr 2008
DOIs
Publication statusPublished - 2 Jun 2008

Keywords

  • dimer
  • DNA
  • excimer
  • fluorescence
  • photophysics
  • TIME-RESOLVED FLUORESCENCE
  • MEDIATED ELECTRON-TRANSFER
  • EXCITED-STATE DYNAMICS
  • BASE STACKING
  • NUCLEOTIDE INCORPORATION
  • CHARGE-TRANSPORT
  • NUCLEIC-ACIDS
  • ABASIC SITES
  • STRANDED-DNA
  • ACTIVE-SITE

Cite this