Fitted parameters for tail-deuterated DMPC/DMPG membranes prior to and after exposure to 1 μM 3W32 and 3W62 peptide. The amount of peptide incorporated in the different layers is estimated based on the change in SLD observed after exposure to the peptide.
| Layer | d [Å] | Coverage [%] | SLD [10−6 Å−2] | Peptide vol% | d [Å] | Coverage [%] | SLD [10−6 Å−2] | Peptide vol% |
|---|---|---|---|---|---|---|---|---|
| Pristine SLB | ||||||||
| Water | 3 | 0 | — | — | 4 ± 1 | 0 | — | — |
| Head (inner) | 6 ± 1 | 85 ± 3 | 1.83 | — | 6 ± 1 | 83 ± 3 | 1.83 | — |
| Tail | 26 ± 1 | 95 ± 1 | 6.7 | — | 27 ± 1 | 94 ± 1 | 6.7 | — |
| Head (upper) | 6 ± 1 | 85 ± 3 | 1.83 | — | 6 ± 1 | 83 ± 3 | 1.83 | — |
| Total membrane thickness (Å) | 38 ± 2 | A mol = 63 ± 3 Å 2 | 39 ± 2 | A mol = 61 ± 2 Å 2 | ||||
| SLB after addition of | 1 μM 3W32 | 1 μM 3W62 | ||||||
| Water | 3 | 0 | — | — | 4 ± 1 | 0 | — | — |
| Head (inner) | 6 ± 1 | 85 ± 3 | 1.83 | — | 6 ± 1 | 85 ± 3 | 1.83 | — |
| Tail/peptide | 26 ± 1 | 95 ± 1 | 6.25 | 5 ± 1 | 26 ± 1 | 90 ± 1 | 6.0 | 11 ± 1 |
| Head/peptide | 7 ± 1 | 75 ± 4 | 1.75 | 8 ± 2 | 6 ± 1 | 72 ± 4 | 1.78 | 13 ± 2 |
| Total membrane thickness (Å) | 39 ± 2 | A mol N/A | 38 ± 2 | A mol N/A | ||||
| Peptide layer | — | — | — | — | 46 ± 1 | 12 ± 1 | 1.5/2.2/3.2 ± 0.2a | 100 |
a
SLD of peptide taking into account D/H exchange, see ESI Table S1. Fixed parameters during fitting.