TABLE 3.
Individual local frequencies (ν) and local opening times (τ) of the AmB channels observed in E. coli IOM and egg lecithin bilayers in the presence or absence of sterols and different temperatures
| Local frequency (Hz)
|
Local average open time (sec)
|
||||||||
|---|---|---|---|---|---|---|---|---|---|
| 30 mol %
|
30 mol %
|
||||||||
| 0 mol%
|
Cholesterol
|
Ergosterol
|
0 mol%
|
Cholesterol
|
Ergosterol
|
||||
| Bilayer | Channel type | 15°C | 25°C | 25°C | 25°C | 15°C | 25°C | 25°C | 25°C |
| [AmB] (M): | 10−4
|
10−4*
|
10−5
|
|
10−4
|
10−4*
|
10−5
|
||
| E. coli IOM | I | 0.5 (0.1) | 0.4 (0.01) | 49 (—) | 0.43 | 0.26 | ∼10−3 | ||
| II | 0.5 (0.2) | 0.4 (0.04) | 16 (1) | 0.64 | 0.36 | ∼10−4 | |||
| III | 0.7 (0.2) | 0.5 (0.02) | 23 (4) | 0.42 | 0.09 | ∼10−4 | |||
| IV | nob | 0.3 (0.08) | 32 (9) | nob | 0.11 | 0.03 | |||
| V | nob | nob | 21 (4) | nob | nob | ∼10−4 | |||
| VI | nob | 0.2 (0.04) | 4 (1) | nob | 0.25 | ∼10−3 | |||
| [AmB] (M): | 10−4
|
10−4
|
10−5
|
10−5†
|
10−4
|
10−4
|
10−5
|
10−5† | |
| Egg lecithin | I | 6.1 (2.2) | nob | 19.1 (1.3) | 1.7 (0.9) | 0.04 | nob | 0.04 | 0.06 |
| II | 1.3 (0.7) | 1.1 (0.1) | 17.2 (3.9) | 3.6 (1.3) | 0.39 | 0.11 | ∼10−3 | 0.39 | |
| III | 2.5 (0.9) | 1.7 (0.6) | 21.5 (5.1) | 0.6 (0.2) | 0.24 | 0.24 | ∼10−3 | 0.35 | |
| IV | nob | 1.8 (0.5) | 30.4 (10.8) | 1.7 (0.6) | nob | 0.02 | 0.02 | 0.05 | |
| V | 15.2 (3.2) | nob | 25.1 (6.4) | 8.0 (2.2) | 0.01 | nob | 0.01 | 0.02 | |
| VI | nob | nob | 20.8 (4.9) | 0.6 (0.2) | nob | nob | 0.01 | 0.01 | |
200 mV were applied for DMPC with cholesterol, lecithin with cholesterol and E. coli. 100 mV were used for DMPC withoug cholesterol, lecithin without cholesterol, and lecithin with ergosterol. The buffer used was 2M KCl, 1mM CaCl2, and 10 mM Hepes at pH 8.0. nob, not observed; ( ), standard error.
*
Incorporation of AmB into the lipid chloroform mixture.
†
Incorporation of AmB into the membrane patch external solution.