Table 2.
Comparison of experimental Hofmeister salt m-values for protein (lac DBD) unfolding and 12-bp DNA melting (Eq. 7) with predictions from an ASA analysis of model compound data
| lac DBD unfolding m-value/RT, (m-1) | 12-bp DNA duplex melting m-value/RT, (m-1) | |||
| Salt | Experimental | Predicted* | Experimental | Predicted† |
| Na2SO4 | — | — | −0.1 ± 0.2 | −0.2 ± 0.5 |
| (NH4)2SO4 | 4.6 ± 0.2 | 5.4 ± 0.2 | — | — |
| KF | 2.3 ± 0.1 | 3.9 ± 0.5 | −0.4 ± 0.1 | −1.3 ± 0.3 |
| (GuH)2SO4 | 1.5 ± 0.1 | 1.0 ± 0.5 | −2.6 ± 0.3 | −3.1 ± 0.3 |
| KCl | 1.3 ± 0.1 | 1.6 ± 0.2 | −1.0 ± 0.1 | −1.8 ± 0.2 |
| NaCl | — | — | −1.1 ± 0.1 | −1.7 ± 0.2 |
| NH4Cl | 0.8 ± 0.1 | 0.9 ± 0.6 | — | — |
| KBr | — | — | −1.5 ± 0.1 | −2.1 ± 0.3 |
| GuHCl | −1.2 ± 0.1 | −1.3 ± 0.3 | −3.6 ± 0.2 | −3.5 ± 0.4 |
| NaClO4 | — | — | −3.6 ± 0.2 | −4.3 ± 0.3 |
*Based on 92% of ΔASA; remaining 8% assigned zero contribution.
†Based on 64% of ΔASA; remaining 36% assigned zero contribution.