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Published on: July 6, 2016
2-Phenanthrenyl-DNA: synthesis, pairing, and fluorescence properties
Nikolay A Grigorenko1, Christian J Leumann
1Department of Chemistry & Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 5, 2008
Summary
Synthesized phenanthrenyl-deoxyribonucleosides were incorporated into DNA duplexes, enhancing stability and enabling fluorescence quenching. These modified nucleosides offer new possibilities for DNA nanotechnology and diagnostics.
Area of Science:
- Synthetic organic chemistry
- Nucleic acid chemistry
- Biophysical chemistry
Background:
- Phenanthrenyl nucleosides offer unique structural and electronic properties for DNA modification.
- Interstrand stacking interactions are crucial for DNA duplex stability and recognition.
Purpose of the Study:
- To synthesize and incorporate novel 2'-phenanthrenyl-C-deoxyribonucleosides into DNA.
- To investigate the impact of phenanthrenyl modifications on DNA duplex stability, thermodynamics, and fluorescence properties.
Main Methods:
- Chemical synthesis of phenanthrenyl-deoxyribonucleosides with varying substituents (phenNH(2), phenNO(2), phenH).
- Oligodeoxyribonucleotide synthesis and incorporation of modified nucleosides.
- UV melting analysis for thermal stability and thermodynamic studies (Van't Hoff analysis).
- Fluorescence spectroscopy to study energy and electron transfer processes.
Main Results:
- Incorporation of phenanthrenyl residues significantly altered duplex thermal stability (up to +11.3 °C).
- Increased thermodynamic stability was primarily enthalpic for phenH and phenNO(2) modifications.
- Phenanthrenyl residues in bulge positions affected duplex stability, with phenNO(2) causing destabilization near mismatches.
- PhenNO(2) acted as an efficient fluorescence quencher for phenH and phenNH(2), indicating efficient energy/electron transfer.
Conclusions:
- Phenanthrenyl-modified deoxyribonucleosides can modulate DNA duplex stability and thermodynamic properties.
- The electronic nature of phenanthrenyl substituents influences stability and fluorescence behavior.
- These findings highlight the potential of phenanthrenyl nucleosides for applications in DNA-based sensing and nanotechnology.
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