Dipolar couplings in multiple alignments suggest alpha helical motion in ubiquitin.

Meiler J, Peti W, Griesinger C
J Am Chem Soc. 2003 125 (27): 8072-3

PMID: 12837055 · DOI:10.1021/ja029816l

Recently, residual dipolar couplings (RDCs) of backbone N-HN vectors measured in 11 different alignment media were analyzed with respect to structure and dynamics in a model-free way in terms of generalized order parameters and motional anisotropies. The anisotropies in the central alpha-helix were found to be strikingly uniformly distributed. In this communication, these parameters are further interpreted in terms of physically feasible cooperative reorientational motion of the helix with respect to the core of the protein. The RDCs are compatible with a model in which all N-HN vectors of the alpha-helix of ubiquitin exhibit correlated anisotropic excursions with amplitudes of 21 degrees and 12 degrees along two orthogonal directions x' ' and y' ' of a coordinate system C' ', if z' ' represents the helix axis. Such motion contradicts neither NOE data nor molecular force-field calculations.

MeSH Terms (4)

Models, Chemical Protein Structure, Secondary Thermodynamics Ubiquitin

Connections (2)

This publication is referenced by other Labnodes entities: