Table 1.
Properties of dimeric pairs
| tm, °C | Ku, M | ΔGu, kcal/mol | Heterodimer specificity | |
|---|---|---|---|---|
| B−/B− | 22.9 | 5.9 × 10−6 | 7.1 | |
| B+/B+ | 24.8 | 5.0 × 10−6 | 7.2 | |
| A+/A+ | 35.1 | 1.1 × 10−6 | 8.1 | |
| A−/A− | 40.4 | 4.7 × 10−7 | 8.6 | |
| A+/A− | 37.9 | 3.9 × 10−7 | 8.7 | 0.9 |
| B+/A− | 40.5 | 1.5 × 10−7 | 9.3 | 4.4 |
| B+/B− | 45.5 | 5.0 × 10−8 | 9.9 | 55 |
| A+/B− | 46.0 | 2.8 × 10−8 | 10.3 | 39 |
| Wild type | 54.0 | 8.0 × 10−9 | 11.0 |
tm values were determined at a total protein concentration of 5 μM for homodimers and 2.5 μM each for heterodimers. Ku values for dimer dissociation and denaturation were calculated at 25°C, 250 mM KCl, pH 7.5. ΔGu values were calculated under the same conditions using a standard-state concentration of 1 M. Heterodimer specificity was calculated as the ratio of heterodimer/homodimers at 25°C with 2.5 μM total concentrations of each variant in monomer equivalents. In comparing the stabilities of homodimers and heterodimers at the same total subunit concentration, homodimers have a statistical advantage. Data for wild-type Arc-st11 taken from ref. 17.