On the combined analysis of ²H and ¹?N/¹H solid-state NMR data for determination of transmembrane peptide orientation and dynamics.

ABSTRACT: The dynamics of membrane-spanning peptides have a strong affect on the solid-state NMR observables. We present a combined analysis of ²H-alanine quadrupolar splittings together with ¹?N/(1)H dipolar couplings and ¹?N chemical shifts, using two models to treat the dynamics, for the systematic evaluation of transmembrane peptides based on the GWALP23 sequence (acetyl-GGALW(LA)?LWLAGA-amide). The results indicate that derivatives of GWALP23 incorporating diverse guest residues adopt a range of apparent tilt angles that span 5°-35° in lipid bilayer membranes. By comparing individual and combined analyses of specifically ²H- or ¹?N-labeled peptides incorporated in magnetically or mechanically aligned lipid bilayers, we examine the influence of data-set size/identity, and of explicitly modeled dynamics, on the deduced average orientations of the peptides. We conclude that peptides with small apparent tilt values (

SUBMITTER: Vostrikov VV 

PROVIDER: S-EPMC3244059 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature