A caged lanthanide complex as a paramagnetic shift agent for protein NMR.

Miguel Prudêncio; Jan Rohovec; Joop A Peters; Elitza Tocheva; Martin J Boulanger; Michael E P Murphy; Hermen-Jan Hupkes; Walter Kosters; Antonietta Impagliazzo; Marcellus Ubbink

doi:10.1002/chem.200306019

PubMed · 15224334

A caged lanthanide complex as a paramagnetic shift agent for protein NMR.

Miguel Prudêncio·Jan Rohovec·Joop A Peters·Elitza Tocheva·Martin J Boulanger·Michael E P Murphy·Hermen-Jan Hupkes·Walter Kosters·Antonietta Impagliazzo·Marcellus Ubbink

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Abstract

A lanthanide complex, named CLaNP (caged lanthanide NMR probe) has been developed for the characterisation of proteins by paramagnetic NMR spectroscopy. The probe consists of a lanthanide chelated by a derivative of DTPA (diethylenetriaminepentaacetic acid) with two thiol reactive functional groups. The CLaNP molecule is attached to a protein by two engineered, surface-exposed, Cys residues in a bidentate manner. This drastically limits the dynamics of the metal relative to the protein and enables measurements of pseudocontact shifts. NMR spectroscopy experiments on a diamagnetic control and the crystal structure of the probe-protein complex demonstrate that the protein structure is not affected by probe attachment. The probe is able to induce pseudocontact shifts to at least 40 A from the metal and causes residual dipolar couplings due to alignment at a high magnetic field. The molecule exists in several isomeric forms with different paramagnetic tensors; this provides a fast way to obtain long-range distance restraints.

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Azurin Crystallography, X-Ray Lanthanoid Series Elements Mass Spectrometry Models, Molecular Nuclear Magnetic Resonance, Biomolecular Pentetic Acid Journal Article Research Support, Non-U.S. Gov't

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Miguel Prudêncio, Jan Rohovec, Joop A Peters, Elitza Tocheva, Martin J Boulanger, Michael E P Murphy, Hermen-Jan Hupkes, Walter Kosters, Antonietta Impagliazzo, Marcellus Ubbink. 2004-07-05. A caged lanthanide complex as a paramagnetic shift agent for protein NMR.. https://doi.org/10.1002/chem.200306019

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