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Engineering of a Red Fluorogenic Protein/Merocyanine Complex for Live-Cell Imaging.

ABSTRACT: A reengineered human cellular retinol binding protein?II (hCRBPII), a 15-kDa protein belonging to the intracellular lipid binding protein (iLBP) family, generates a highly fluorescent red pigment through the covalent linkage of a merocyanine aldehyde to an active site lysine residue. The complex exhibits "turn-on" fluorescence, due to a weakly fluorescent aldehyde that "lights up" with subsequent formation of a strongly fluorescent merocyanine dye within the binding pocket of the protein. Cellular penetration of merocyanine is rapid, and fluorophore maturation is nearly instantaneous. The hCRBPII/merocyanine complex displays high quantum yield, low cytotoxicity, specificity in labeling organelles, and compatibility in both cancer cell lines and yeast cells. The hCRBPII/merocyanine tag is brighter than most common red fluorescent proteins.

SUBMITTER: Santos EM

PROVIDER: S-EPMC7379159 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Engineering of a Red Fluorogenic Protein/Merocyanine Complex for Live-Cell Imaging.

Santos Elizabeth M EM Berbasova Tetyana T Wang Wenjing W Salmani Rahele Esmatpour RE Sheng Wei W Vasileiou Chrysoula C Geiger James H JH Borhan Babak B

Chembiochem : a European journal of chemical biology 20191113 5

A reengineered human cellular retinol binding protein II (hCRBPII), a 15-kDa protein belonging to the intracellular lipid binding protein (iLBP) family, generates a highly fluorescent red pigment through the covalent linkage of a merocyanine aldehyde to an active site lysine residue. The complex exhibits "turn-on" fluorescence, due to a weakly fluorescent aldehyde that "lights up" with subsequent formation of a strongly fluorescent merocyanine dye within the binding pocket of the protein. Cellul ...[more]

PMID: 31482666

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