Stable and rigid DTPA-like paramagnetic tags suitable for in vitro and in situ protein NMR analysis.
 

Stable and rigid DTPA-like paramagnetic tags suitable for in vitro and in situ protein NMR analysis.

Stable and rigid DTPA-like paramagnetic tags suitable for in vitro and in situ protein NMR analysis.

J Biomol NMR. 2017 Dec 09;:

Authors: Chen JL, Zhao Y, Gong YJ, Pan BB, Wang X, Su XC

Abstract
Organic synthesis of a ligand with high binding affinities for paramagnetic lanthanide ions is an effective way of generating paramagnetic effects on proteins. These paramagnetic effects manifested in high-resolution NMR spectroscopy are valuable dynamic and structural restraints of proteins and protein-ligand complexes. A paramagnetic tag generally contains a metal chelating moiety and a reactive group for protein modification. Herein we report two new DTPA-like tags, 4PS-PyDTTA and 4PS-6M-PyDTTA that can be site-specifically attached to a protein with a stable thioether bond. Both protein-tag adducts form stable lanthanide complexes, of which the binding affinities and paramagnetic tensors are tunable with respect to the 6-methyl group in pyridine. Paramagnetic relaxation enhancement (PRE) effects of Gd(III) complex on protein-tag adducts were evaluated in comparison with pseudocontact shift (PCS), and the results indicated that both 4PS-PyDTTA and 4PS-6M-PyDTTA tags are rigid and present high-quality PREs that are crucially important in elucidation of the dynamics and interactions of proteins and protein-ligand complexes. We also show that these two tags are suitable for in-situ protein NMR analysis.


PMID: 29224182 [PubMed - as supplied by publisher]



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