Table 1.
Melting temperatures (Tm) of duplex DNA containing C–T, G-T or T–T mismatches or A–T base pairs in the presence and absence of 2 equiv of HgII and AgIa
| Sequence | T m (°C) no metal ions | T m (°C), (ΔTm) with HgII | T m (°C), (ΔTm) with AgI |
|---|---|---|---|
| ODN15 ‘C–T’ | 35.1 ± 0.3 | 39.3 ± 0.2 (+4.2) | 44.0 ± 0.2 (+8.9) |
| ODN16 ‘T–T’ | 37.9 ± 0.1 | 57.3 ± 0.1 (+19.4) | 36.2 ± 0.5 (−1.7) |
| ODN17 ‘G–T’ | 47.3 ± 0.4 | 41.6 ± 0.8 (−5.7) | 45.5 ± 0.4 (−1.8) |
| ODN18 ‘A–T’ | 57.1 ± 0.1 | 53.2 ± 0.8 (−3.9) | 57.2 ± 0.7 (+0.1) |
a Reported values = mean ± standard deviation from three independent measurements. ΔTm reflects the difference in Tm upon addition of 2 equiv metal ions per mismatch present. All samples contained 10 μM of duplex DNA in aqueous buffer (200 mM NaClO4, 50 mM cacodylic acid at pH 7.0). For duplex sequences see Figure 3A and Supplementary Table S2, SI. For raw melting data see Figure 4 and Supplementary Figures S4 and S5, SI.