Table 1. Thermodynamic stability of DNA·RNA hybrids: effect of pyrimidine (C5) modifications.
| Sequence | ΔG(298) (kJ mol–1) | ΔH (kJ mol–1) | ΔS (kJ mol–1 K–1) | Tm (1 µM) (K) | ΔTm (K) | Modification | |
|---|---|---|---|---|---|---|---|
| R strand | Y strand | ||||||
| dR10·dY10a | –42.9 | –290 | –0.829 | 307 | +2 | – | +Me |
| dR10·dY(U)10 | –41.3 | –283 | –0.811 | 305 | 0 | – | – |
| dR10·rY10a | –31.5 | –238 | –0.693 | 294 | –11 | – | +OH |
| dR10·rY(T)10 | –39.9 | –275 | –0.789 | 304 | –1 | – | +OH, +Me |
| rR10·dY(U)10 | –65.3 | –397 | –1.113 | 323 | +18 | +OH | – |
| rR10·dY10a | –56.1 | –343 | –0.963 | 318 | +13 | +OH | +Me |
| rR10·dPY10 | –107.5 | –441 | –1.119 | 357 | +52 | +OH | +Propynyl |
| rR10·rY10a | –66.8 | –394 | –1.098 | 325 | +20 | +OH | +OH |
| rR10·rY(T)10 | –87.7 | –420 | –1.115 | 341 | +36 | +OH | +OH, +Me |
aData from Gyi et al. (8).