Weak alignment of paramagnetic proteins warrants correction for residual CSA effects in measurements of pseudocontact shifts
Date
2005
Authors
John, Michael
Park, Ah Young
Pintacuda, Guido
Dixon, Nicholas
Otting, Gottfried
Journal Title
Journal ISSN
Volume Title
Publisher
American Chemical Society
Abstract
Paramagnetic metal ions can induce molecular alignment with respect to the magnetic field. This alignment generates residual anisotropic chemical shifts (RACS) due to nonisotropic averaging over the molecular orientations. Using a 30 kDa protein-protein complex, the RACS effects are shown to be significant for heteronuclear spins with large chemical shift anisotropies, lanthanide ions with large anisotropic magnetic susceptibility tensors, and measurements at high magnetic field. Therefore, RACS must be taken into account when pseudocontact shifts are measured by comparison of chemical shifts observed between complexes with paramagnetic and diamagnetic lanthanide ions. The results are of particular importance when different pseudocontact shifts measured for the1HN,15N, and13C′ spins of a peptide group are used to restrain its orientation with respect to the electronic magnetic susceptibility tensor in structure calculations.
Description
Keywords
Keywords: metal ion; metalloprotein; protein; anisotropy; article; calculation; carbon nuclear magnetic resonance; chemical shift anisotropy; density functional theory; magnetic field; magnetism; measurement; metal binding; nitrogen nuclear magnetic resonance; nucl
Citation
Collections
Source
Journal of the American Chemical Society
Type
Journal article
Book Title
Entity type
Access Statement
License Rights
Restricted until
2037-12-31
Downloads
File
Description