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Chemoselective ratiometric imaging of protein S-sulfenylation.

ABSTRACT: Here we report a ratiometric fluorescent probe for chemoselective conjugation to sulfenic acids in living cells. Our approach couples an ?-fluoro-substituted dimedone to an aminonaphthalene fluorophore (F-DiNap), which upon sulfenic acid conjugation is locked as the 1,3-diketone, changing the fluorophore excitation. F-DiNap reacts with S-sulfenylated proteins at equivalent rates to current probes, but the ?-fluorine substitution blocks side-reactions with biological aldehydes.

SUBMITTER: Tom CTMB

PROVIDER: S-EPMC5765544 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Chemoselective ratiometric imaging of protein S-sulfenylation.

Tom Christopher T M B CTMB Crellin John E JE Motiwala Hashim F HF Stone Matthew B MB Davda Dahvid D Walker William W Kuo Yu-Hsuan YH Hernandez Jeannie L JL Labby Kristin J KJ Gomez-Rodriguez Lyanne L Jenkins Paul M PM Veatch Sarah L SL Martin Brent R BR

Chemical communications (Cambridge, England) 20170601 53

Here we report a ratiometric fluorescent probe for chemoselective conjugation to sulfenic acids in living cells. Our approach couples an α-fluoro-substituted dimedone to an aminonaphthalene fluorophore (F-DiNap), which upon sulfenic acid conjugation is locked as the 1,3-diketone, changing the fluorophore excitation. F-DiNap reacts with S-sulfenylated proteins at equivalent rates to current probes, but the α-fluorine substitution blocks side-reactions with biological aldehydes. ...[more]

PMID: 28613292

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