Table 3. Dissociation Constants (Kd) for Binding of 1–4 to 20-mer Duplex, G-Quadruplex (G4), and Three-Way Junction (3WJ) DNA Measured Using Cy5.5-Labeled Oligonucleotides and FRETa.
duplex |
G4 |
3WJ |
||||
---|---|---|---|---|---|---|
complex | Kd (μM) | r (Å) | Kd (μM) | r (Å) | Kd (μM) | r (Å) |
1 | 2.8 ± 0.9 | 33.5 | 3.9 ± 1.3 | 26.8 | 4.3 ± 0.9 | 37.4 |
2 | 2.3 ± 0.5 | 33.1 | 3.8 ± 1.7 | 30.0 | 4.4 ± 0.7 | 35.0 |
3 | 6.3 ± 0.3 | 23.8 | nd | nd | nd | nd |
4 | 2.6 ± 1.0 | 55.9 | nd | nd | 6.4 ± 0.3 | 49.6 |