Solid-state NMR spin diffusion for measurement of membrane-bound peptide structure: gramicidin A.
A recently developed solid-state NMR method for measurement of depths in membrane systems is applied to gramicidin A, a membrane-bound peptide of known structure, to investigate the potential of this method. (15)N-detected, (1)H spin diffusion experiments demonstrate the resolution of the technique by measuring the 4-5 A depth differences between three (15)N-labeled backbone sites (Trp13, Val7, Gly2) in gramicidin A. We also show that (13)C-detected, (1)H spin diffusion experiments on unlabeled gramicidin A are sufficient to discriminate between the end-to-end dimer and double-helix structures of gramicidin A. Thus, spin diffusion solid-state NMR experiments can provide a simple approach, which does not require labeled samples, for testing structural models of membrane-bound peptides.
Gallagher
Greg J
GJ
Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003-9336, USA.
Hong
Mei
M
Thompson
Lynmarie K
LK
D006096:Gramicidin / Q000737:chemistry*; D008565:Membrane Proteins / Q000737:chemistry*; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation
D008565:Membrane Proteins; D006096:Gramicidin