A bifunctional spin label reports the structural topology of phospholamban in magnetically-aligned bicelles.

ABSTRACT: We have applied a bifunctional spin label and EPR spectroscopy to determine membrane protein structural topology in magnetically-aligned bicelles, using monomeric phospholamban (PLB) as a model system. Bicelles are a powerful tool for studying membrane proteins by NMR and EPR spectroscopies, where magnetic alignment yields topological constraints by resolving the anisotropic spectral properties of nuclear and electron spins. However, EPR bicelle studies are often hindered by the rotational mobility of monofunctional Cys-linked spin labels, which obscures their orientation relative to the protein backbone. The rigid and stereospecific TOAC label provides high orientational sensitivity but must be introduced via solid-phase peptide synthesis, precluding its use in large proteins. Here we sho

SUBMITTER: McCaffrey JE 

PROVIDER: S-EPMC4716873 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature