Abstract
Site directed spin labeling is used to investigate the protein annexin 12 absorbed on a single planar phospholipid bilayer of approximately . Electron paramagnetic resonance spectra of nitroxide side chain at several topological sites reveal a conserved tertiary fold of the protein in the absorbed state, in agreement with earlier diffraction results. The angular dependent spectra of the two-dimensional microcrystals are shown to provide information on the degree of ordering of spin labels in a -helix and in turn on the orientation of the -helix with respect to the surface.
- Received 10 March 2003
DOI:https://doi.org/10.1103/PhysRevLett.91.188101
©2003 American Physical Society