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19F NMR spectroscopy monitors ligand binding to recombinantly fluorine-labelled b'x from human protein disulphide isomerase (hPDI).

ABSTRACT: We report a protein-observe (19)F NMR-based ligand titration binding study of human PDI b'x with ?-somatostatin that also emphasises the need to optimise recombinant protein fluorination when using 5- or 6-fluoroindole. This study highlights a recombinant preference for 5-fluoroindole over 6-fluoroindole; most likely due to the influence of fluorine atomic packing within the folded protein structure. Fluorination affords a single (19)F resonance probe to follow displacement of the protein x-linker as ligand is titrated and provides a dissociation constant of 23 ± 4 ?M.

SUBMITTER: Curtis-Marof R

PROVIDER: S-EPMC4157668 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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19F NMR spectroscopy monitors ligand binding to recombinantly fluorine-labelled b'x from human protein disulphide isomerase (hPDI).

Curtis-Marof Rose R Doko Denisa D Rowe Michelle L ML Richards Kirsty L KL Williamson Richard A RA Howard Mark J MJ

Organic & biomolecular chemistry 20140601 23

We report a protein-observe (19)F NMR-based ligand titration binding study of human PDI b'x with Δ-somatostatin that also emphasises the need to optimise recombinant protein fluorination when using 5- or 6-fluoroindole. This study highlights a recombinant preference for 5-fluoroindole over 6-fluoroindole; most likely due to the influence of fluorine atomic packing within the folded protein structure. Fluorination affords a single (19)F resonance probe to follow displacement of the protein x-link ...[more]

PMID: 24796794

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