Table 1.
Summary of biophysical properties measured for myoc-OLF samples in this study.
| Secondary Structure Tm ( °C) |
Tertiary Structure Tm ( °C) |
ANS Fl. | ΔFThT/Foa | Fibril Growth t1/2 (hrs) |
Fibril Morphology |
|
|---|---|---|---|---|---|---|
|
Wild-type myoc-OLF |
||||||
| pH 7.2 | 51.5 ± 0.1 | 48.9 ± 0.6 | 0.9 ± 0.5 | 2.4 | ---- | |
| 70.6b | 2.0 | Straight | ||||
| pH 5.8 | 52.7 ± 0.1 | 52.0 ± 0.4 | 1.1 ± 0.7 | −0.4 | ---- | |
| pH 4.6 | 48.7 ± 0.1 | 46.0 ± 0.3 | 10.6 ± 0.4 | 2.3 | ---- | |
| pH 3.4 | 34.0 ± 0.6 | 29.0 ± 1.3 | 181.5 ± 2.3 | 79.8 | 0.4 ± 0.2 |
Long, straight |
| pH 2 | N/A | N/A | 298.3 ± 6.9 | −1.7 | ---- | |
| pH 7.2/NaCl | 52.2 ± 0.6 | 50.9 ± 0.2 | 1.1 ± 1.1 | −0.7 | ||
| 89.4b | 27.7 ± 2.6 | Circular | ||||
| pH 5.8/NaCl | 54.0 ± 0.1 | 52.8 ± 0.3 | 1.4 ± 1.4 | −0.5 | ---- | |
| pH 4.6/NaCl | 46.4 ± 0.1 | 43.1 ± 0.2 | 4.5 ± 2.3 | −0.5 | 9.5 ± 3.9 |
Long, straight |
| pH 3.4/NaCl | N/A | N/A | 234.7 ± 3.9 | 21.5 | ---- | |
| pH 2/NaCl | N/A | N/A | 346.8 ± 24.0 | 16.0 | ---- | |
|
Myoc-OLF variants |
||||||
| I499F | 45.0 ± 1.1 | 43.2 ± 0.5 | 3.4 ± 1.1 | 88.0 | 3.5 ± 0.2 |
Straight fibrils and oligomers |
| D380A | 46.8 ± 0.1 | 44.4 ± 0.6 | 2.1 ± 0.4 | 102.2 | 11.9 ± 4.7 | Circular |
| A427T | 48.9 ± 0.1 | 45.9 ± 0.2 | 1.3 ± 0.1 | 28.5 | >25c |
Straight fibrils and oligomers |
| K398R | 51.1 ± 0.4 | 49.5 ± 2.4 | 0.6 ± 0.2 | −0.7 | ---- |
Bold: Fibrillar structures confirmed by AFM.
N/A: Not available because secondary structure is already disordered at 4 °C.
a
ThT fluorescence recorded after incubation for 18 h (no salt) or 50 h (200mM NaCl) at 36 °C.
b
ThT fluorescence recorded after incubation for 18 h (no salt) or 90 h (200mM NaCl) at 42 °C.
c
Steady-state maximum not reached by termination of experiment at 50 h.