TABLE 1.
α-Helical content, thermodynamic parameters, and ANS fluorescence for lipid-free WT apoA-I and the apoA-I mutant forms
| α-Helixa (%) | Tmb (°C) | ΔHvb (kcal/mol) | Ic (relative units) | WMFc (nm) | |
| WT apoA-I | 56 ± 2 | 62 ± 1 | 41 ± 2 | 1.0 | 474 |
| apoA-I[ R123A] | 58 ± 3 | 63 ± 1 | 45 ± 2 | 0.8 | 477 (+3) |
| apoA-I[R123E] | 59 ± 2 | 64 ± 1 | 43 ± 2 | 0.8 | 476 (+2) |
| apoA-I[R131A] | 57 ± 2 | 64 ± 1 | 44 ± 2 | 1.0 | 474 |
The values are mean ± SD from at least three experiments.
a
Estimated from the [Θ222] at 25°C.
b
The melting temperature, Tm, and van’t Hoff enthalpy, ΔHv, were determined from van’t Hoff analysis of thermal unfolding curves monitored by CD.
c
Parameters of ANS fluorescence were determined in the presence of WT apoA-I or one of the apoA-I mutants. I, ANS fluorescence intensity in relative units compared with the fluorescence in the presence of WT apoA-I.