Table 2.
Melting and thermodynamic data for duplexes with single and double substitutions.
| DNA Duplex |
Tm @ 3 μM (°C) |
ΔG°37,melt (kcal/mol) |
ΔG°25,melt (kcal/mol) |
ΔG°25,itc (kcal/mol) |
|---|---|---|---|---|
| T•A | 51.3 | −12.80 (± 0.20) | −16.02 (± 0.36) | −12.22 (± 0.06)a |
| T•G | 43.4 | −10.38 (± 0.04) | −13.21 (± 0.13) | −11.04 (± 0.05) |
| T•T | 38.1 | − 8.95 (± 0.02) | −11.57 (± 0.09) | −10.50 (± 0.04) |
| T•C | 37.4 | − 8.80 (± 0.02) | −11.52 (± 0.07) | −10.18 (± 0.03) |
| L•A | 40.7 | − 9.54 (± 0.03) | −12.01 (± 0.07) | −10.58 (± 0.05) |
| L•G | 36.8 | − 8.62 (± 0.03) | −10.78 (± 0.14) | − 9.86 (± 0.04) |
| L•T | 35.0 | − 8.26 (± 0.05) | −10.39 (± 0.10) | − 9.49 (± 0.03) |
| L•C | 33.5 | − 8.00 (± 0.02) | −10.10 (± 0.04) | − 9.11 (± 0.03) |
| F•A | 38.7 | − 9.00 (± 0.07) | −11.57 (± 0.16) | −10.36 (± 0.03) |
| F•G | 36.0 | − 8.46 (± 0.03) | −10.93 (± 0.06) | − 9.79 (± 0.03) |
| F•T | 34.6 | − 8.22 (± 0.07) | −10.44 (± 0.12) | − 9.59 (± 0.03) |
| F•C | 33.9 | − 7.98 (± 0.06) | −10.31 (± 0.08) | − 9.55 (± 0.02) |
| 23L•A | 36.8 | − 8.64 (± 0.13) | −10.90 (± 0.17) | nd |
| 23L•G | 37.3 | − 8.80 (± 0.09) | −11.22 (± 0.18) | nd |
| 23L•T | 35.8 | − 8.46 (± 0.10) | −10.55 (± 0.19) | nd |
| 23L•C | 34.8 | − 8.20 (± 0.04) | −10.42 (± 0.09) | nd |
| AT•AT | 55.0 | −14.18 (± 0.16) | −17.49 (± 0.26) | −13.04 (± 0.11)a |
| GT•GT | 42.4 | −10.32 (± 0.15) | −13.55 (± 0.34) | −10.97 (± 0.05) |
| TT•TT | 34.2 | − 7.87 (± 0.03) | −11.09 (± 0.06) | −10.14 (± 0.01) |
| CT•CT | 31.9 | − 7.28 (± 0.04) | −10.28 (± 0.04) | − 9.39 (± 0.02) |
| AL•AL | 35.6 | − 8.34 (± 0.02) | −10.96 (± 0.08) | − 9.70 (± 0.04) |
| GL•GL | 29.2 | − 6.82 (± 0.07) | − 9.24 (± 0.03) | − 8.49 (± 0.02) |
| TL•TL | 29.7 | − 6.82 (± 0.04) | − 9.55 (± 0.03) | − 8.70 (± 0.02) |
| CL•CL | 23.4 | − 5.70 (± 0.14) | − 7.99 (± 0.02) | − 7.76 (± 0.02) |
| AF•AF | 30.9 | − 7.22 (± 0.04) | − 9.83 (± 0.05) | − 9.38 (± 0.02) |
| GF•GF | 26.8 | − 6.35 (± 0.11) | − 8.70 (± 0.02) | − 8.48 (± 0.01) |
| TF•TF | 27.3 | − 6.36 (± 0.10) | − 8.91 (± 0.02) | − 8.46 (± 0.01) |
| CF•CF | 24.0 | − 5.70 (± 0.13) | − 8.13 (± 0.01) | − 8.04 (± 0.01) |
| A23L•A23L | 29.1 | − 7.04 (± 0.19) | − 9.24 (± 0.07) | nd |
| G23L•G23L | 30.6 | − 7.26 (± 0.17) | − 9.51 (± 0.09) | nd |
| T23L•T23L | 29.3 | − 7.01 (± 0.10) | − 9.30 (± 0.05) | nd |
| C23L•C23L | 26.3 | − 6.16 (± 0.13) | − 8.65 (± 0.02) | nd |
a
Indirectly estimated by addition of ΔG° values related to the replacement of an F-A base pair with a T-A base pair; see SI.