Table 3.
Assigned quadrupolar splittings from WALP19 peptides in DMPC at 40°C, based on results for selectively labeled tryptophans. The last column lists the averaged θ angles between the C-D bond and the membrane normal (assuming isotropic order parameters of 0.75 (Trp-2&3) and 0.55 (Trp-17&18), along with the error associated with an estimated experimental error of 2 kHz in Δνq.
| Labeled Trp | Bond C-2 | Bond C-5 | ||
|---|---|---|---|---|
| Δνq (kHz) | θ (°) | Δνq (kHz) | θ (°) | |
| Trp-2 | 76 | 40.2 ± 0.4; 73.2 ± 0.7 | 155 | 23.3 ± 0.5 |
| Trp-3 | 53 | 44.6 ± 0.4; 66.5 ± 0.5 | 155 | 23.3 ± 0.5 |
| Trp-17 | 62 | 38.5 ± 0.5; 76.4 ± 1.1 | a | a |
| Trp-18 | 11 | 51.8 ± 0.5, 57.8 ± 0.6 | 63 | 38.3 ± 0.5; 77.0 ± 1.2 |
a
No weaker C-5 peak could be identified for Trp-17.