Mechanisms of Peptide-Induced Pore Formation in Lipid Bilayers Investigated by Oriented 31P Solid-State NMR Spectroscopy
Figure 3
Oriented-sample solid-state 15N and 31P NMR spectra of (a) 15N-Aib8 labeled alamethicin incorporated into oriented DMPC lipids at a peptide:lipid molar ratio of 1∶15 and (b) 15N-Ile14 labeled novicidin in oriented DMPC:DMPG (molar ratio 4∶1) bilayers at 1∶15 peptide:lipid molar ratio.
The resonance in the spectrum of alamethicin is substantially broadened due to mosaic spread [37] and the heterogeneous nature of the peptide-lipid interactions of the peptide [39], [56]. (c,d) 31P spectra of (c) a sample of alamethicin in oriented DMPC lipids with a peptide:lipid ratio of 1∶25 and (d) the novidin sample in (b). (e,f) Models showing the most likely conformations of the peptides and lipids at high peptide:lipid ratio for (e) alamethicin and (f) novicidin in lipid bilayers.