A chemical approach for site-specific identification of NMR signals from protein side-chain NH3 (+) groups forming intermolecular ion pairs in protein-nucleic acid complexes.
Related Articles A chemical approach for site-specific identification of NMR signals from protein side-chain NH3 (+) groups forming intermolecular ion pairs in protein-nucleic acid complexes.
J Biomol NMR. 2015 Feb 19;
Authors: Anderson KM, Nguyen D, Esadze A, Zandrashvili L, Gorenstein DG, Iwahara J
Abstract
Protein-nucleic acid interactions involve intermolecular ion pairs of protein side-chain and DNA or RNA phosphate groups. Using three protein-DNA complexes, we demonstrate that site-specific oxygen-to-sulfur substitution in phosphate groups allows for identification of NMR signals from the protein side-chain NH3 (+) groups forming the intermolecular ion pairs. A characteristic change in their (1)H and (15)N resonances upon this modification (i.e., substitution of phosphate to phosphorodithioate) can represent a signature of an intermolecular ion pair. Hydrogen-bond scalar coupling between protein side-chain (15)N and DNA phosphorodithiaote (31)P nuclei provides direct confirmation of the intermolecular ion pair. The same approach is likely applicable to protein-RNA complexes as well.
PMID: 25690740 [PubMed - as supplied by publisher]
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