Table 1.
Thermodynamic parameters associated to the DMPG phase transition
The phase transition temperature (Tm), the calorimetric enthalpy change (ΔH), and the linewidth at half height (ΔT½) were obtained from analysis of the thermograms with MicroCal Origin software. Lipid-to-protein molar ratios (L/P) are indicated. Data shown are representative of two independent experiments.
| Sample | L/P | Tm °C | ΔH kcal/mol | ΔT½ °C |
|---|---|---|---|---|
| DMPG | ||||
| Blank | 23.3 (2)a | 5.0 (2) | 0.7 (2) | |
| + PlsX wt | 500 | 22.9 (1) | 5.0 (1) | 0.5 (1) |
| + PlsX wt | 400 | 22.8 (1) | 4.5 (1) | 0.6 (1) |
| + PlsX wt | 320 | 23.7 (2) | 4.6 (2) | 2.9 (1) |
| + PlsX wt | 250 | 23.6 (3) | 4.2 (2) | 4.4 (2) |
| + PlsX wt | 136 | 23.6 (3) | 2.9 (3) | 5.1 (2) |
| + PlsX L254E | 136 | 22.8 (1) | 4.5 (1) | 0.6 (1) |
| + PlsX L258E-A259E | 136 | 23.7 (2) | 4.6 (2) | 2.9 (1) |
| + PlsX K264A | 136 | 23.6 (3) | 4.2 (2) | 4.4 (2) |
| + PlsX K271A | 136 | 23.6 (3) | 2.9 (3) | 5.1 (2) |
a The numbers in parentheses correspond to the uncertainties in the last significant digit.