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A Genetically Encoded Ratiometric pH Probe: Wavelength Regulation-Inspired Design of pH Indicators.

ABSTRACT: Mutants of human cellular retinol-binding protein?II (hCRBPII) were engineered to bind a julolidine retinal analogue for the purpose of developing a ratiometric pH sensor. The design relied on the electrostatic influence of a titratable amino acid side chain, which affects the absorption and, thus, the emission of the protein/fluorophore complex. The ratio of emissions obtained at two excitation wavelengths that correspond to the absorption of the two forms of the protein/fluorophore complex, leads to a concentration-independent measure of pH.

SUBMITTER: Berbasova T

PROVIDER: S-EPMC6742514 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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A Genetically Encoded Ratiometric pH Probe: Wavelength Regulation-Inspired Design of pH Indicators.

Berbasova Tetyana T Tahmasebi Nick Setare S Nosrati Meisam M Nossoni Zahra Z Santos Elizabeth M EM Vasileiou Chrysoula C Geiger James H JH Borhan Babak B

Chembiochem : a European journal of chemical biology 20180528 12

Mutants of human cellular retinol-binding protein II (hCRBPII) were engineered to bind a julolidine retinal analogue for the purpose of developing a ratiometric pH sensor. The design relied on the electrostatic influence of a titratable amino acid side chain, which affects the absorption and, thus, the emission of the protein/fluorophore complex. The ratio of emissions obtained at two excitation wavelengths that correspond to the absorption of the two forms of the protein/fluorophore complex, le ...[more]

PMID: 29645331

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