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Fluorinated aromatic amino acids are sensitive 19F NMR probes for bromodomain-ligand interactions.

ABSTRACT: We describe a (19)F NMR method for detecting bromodomain-ligand interactions using fluorine-labeled aromatic amino acids due to the conservation of aromatic residues in the bromodomain binding site. We test the sensitivity, accuracy, and speed of this method with small molecule ligands (+)-JQ1, BI2536, Dinaciclib, TG101348, and acetaminophen using three bromodomains Brd4, BrdT, and BPTF. Simplified (19)F NMR spectra allowed for simultaneous testing of multiple bromodomains to assess selectivity and identification of a new BPTF ligand. Fluorine labeling only modestly affected the Brd4 structure and function assessed by isothermal titration calorimetry, circular dichroism, and X-ray crystallography. The speed, ease of interpretation, and low concentration of protein needed for binding experiments affords a new method to discover and characterize both native and new ligands.

SUBMITTER: Mishra NK

PROVIDER: S-EPMC4273984 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Fluorinated aromatic amino acids are sensitive 19F NMR probes for bromodomain-ligand interactions.

Mishra Neeraj K NK Urick Andrew K AK Ember Stuart W J SW Schönbrunn Ernst E Pomerantz William C WC

ACS chemical biology 20141027 12

We describe a (19)F NMR method for detecting bromodomain-ligand interactions using fluorine-labeled aromatic amino acids due to the conservation of aromatic residues in the bromodomain binding site. We test the sensitivity, accuracy, and speed of this method with small molecule ligands (+)-JQ1, BI2536, Dinaciclib, TG101348, and acetaminophen using three bromodomains Brd4, BrdT, and BPTF. Simplified (19)F NMR spectra allowed for simultaneous testing of multiple bromodomains to assess selectivity ...[more]

PMID: 25290579

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