Regulation of Absorption and Emission in a Protein/Fluorophore Complex.
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ABSTRACT:
SUBMITTER: Santos EM
PROVIDER: S-EPMC11334107 | biostudies-literature | 2024 Aug
REPOSITORIES: biostudies-literature
Publications
Regulation of Absorption and Emission in a Protein/Fluorophore Complex.
Santos Elizabeth M EM Chandra Ishita I Assar Zahra Z Sheng Wei W Ghanbarpour Alireza A Bingham Courtney C Vasileiou Chrysoula C Geiger James H JH Borhan Babak B
ACS chemical biology 20240724 8
Human cellular retinol binding protein II (hCRBPII) was used as a protein engineering platform to rationally regulate absorptive and emissive properties of a covalently bound fluorogenic dye. We demonstrate the binding of a thio-dapoxyl analog via formation of a protonated imine between an active site lysine residue and the chromophore's aldehyde. Rational manipulation of the electrostatics of the binding pocket results in a 204 nm shift in absorption and a 131 nm shift in emission. The protein ...[more]
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