Protein backbone dynamics by solid-state and solution 15N NMR spectroscopy

fd coat protein structure in membrane environments: structural dynamics of the loop between the hydrophobic trans-membrane helix and the amphipathic in-plane helix

“…fd coat protein has all of the characteristic features of a membrane protein; a long hydrophobic trans-membrane helix, a shorter amphipathic helix in the plane of the membrane, a loop connecting the two helices, and unstructured N and C-terminal residues. The statistical measures of resolution of the calculated structures of the protein appear to be limited by the intrinsic motions of three regions of the protein backbone in micelle samples, which we have shown to be essentially the same as those observed in bilayer samples by solid state NMR spectroscopy (Bogusky et al, 1987;Leo et al, 1987;. The N and C-terminal residues are highly mobile on all timescales that can be probed by NMR including 15 N-1 H heteronuclear NOE experiments (Bogusky et al, 1987), although there is limited evidence from some 1 H homonuclear NOEs of helical structure through to the C terminus.…”

Anchoring mechanisms of membrane-associated M13 major coat protein

“…It is generally assumed that the insertion of the protein in a lipid bilayer is accompanied with a major structural rearrangement that splits the continuous ␣-helix in the phage particle into an amphipathic and a transmembrane helix perpendicular to each other (Almeida and Opella, 1997;Bogusky et al, 1988;Bogusky et al, 1987;Henry and Sykes, 1992;Henry et al, 1987;Leo et al, 1987;Marvin, 1998;McDonnell et al, 1993). However, several lines of evidence in recent studies propose that the change in the secondary structure on going from the phage to a matching membrane Fig.…”

NMR structures of membrane proteins in phospholipid bilayers

“…In cases where the protein structure is non-spherical, the reorientation is found to be anisotropic. The overall rotational motions of soluble, globular proteins are well characterized by NMR and other biophysical experiments (Bauer et al, 1975) and in most cases, it is readily possible to distinguish any local backbone motions from the overall reorientation of the protein based on their differences in frequencies, amplitudes, and directions, which generally result in a subset of narrower, more intense, resonances superimposed on the background of broad resonances associated with the folded, structured bulk of the protein (Bogusky et al, 1987). …”