Table 2. Dissociation constants for complexes of deoxynucleotides binding to the termini of DNA hairpins, as determined by NMR titrationa.
| Nucleotide | Templating base | Hairpin | pH | Kd [mM]b | |
|---|---|---|---|---|---|
| dTMP | (1t) | A | (7a) | 8.9 | 241c |
| OAt-dTMP | (2t) | A | (7a) | 8.9 | 71 |
| MeIm-dTMP | (3t) | A | (7a) | 7.0 | 236 |
| dGMP | (1g) | C | (7c) | 8.9 | 27 |
| OAt-dGMP | (2g) | C | (7c) | 8.9 | 26 |
| MeIm-dGMP | (3g) | C | (7c) | 7.0 | 25 |
| dCMP | (1c) | G | (7g) | 8.9 | 34d |
| OAt-dCMP | (2c) | G | (7g) | 8.9 | 25 |
| MeIm-dCMP | (3c) | G | (7g) | 7.0 | 26 |
| dAMP | (1a) | T | (7t) | 8.9 | 38d |
| OAt-dAMP | (2a) | T | (7t) | 8.9 | 20 |
| MeIm-dAMP | (3a) | T | (7t) | 7.0 | 37 |
aConditions: 0.5 to 1 mM hairpin in D2O (99.9%) and phosphate buffer (200 mM), NaCl (400 mM), MgCl2 (80 mM), pH 8.9 or 7.0 (uncorrected for deuterium effect), 20°C.
bDetermined by fit using law of mass action.
cAverage value from two titration experiments.
dFrom (30).