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A genetically encoded multifunctional unnatural amino acid for versatile protein manipulations in living cells.

ABSTRACT: The genetic code expansion strategy allowed incorporation of unnatural amino acids (UAAs) bearing diverse functional groups into proteins, providing a powerful toolkit for protein manipulation in living cells. We report a multifunctional UAA, N?-p-azidobenzyloxycarbonyl lysine (PABK), that possesses a panel of unique properties capable of fulfilling various protein manipulation purposes. In addition to being used as a bioorthogonal ligation handle, an infrared probe and a photo-affinity reagent, PABK was shown to be chemically decaged by trans-cyclooctenols via a strain-promoted 1,3-dipolar cycloaddition, which provides a new bioorthogonal cleavage strategy for intracellular protein activation. The biocompatibility and efficiency of this method were demonstrated by decaging of a PABK-caged firefly luciferase under living conditions. We further extended this method to chemically rescue a bacterial toxin OspF inside mammalian host cells.

SUBMITTER: Ge Y

PROVIDER: S-EPMC5355830 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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A genetically encoded multifunctional unnatural amino acid for versatile protein manipulations in living cells.

Ge Yun Y Fan Xinyuan X Chen Peng R PR

Chemical science 20160801 12

The genetic code expansion strategy allowed incorporation of unnatural amino acids (UAAs) bearing diverse functional groups into proteins, providing a powerful toolkit for protein manipulation in living cells. We report a multifunctional UAA, Nε-p-azidobenzyloxycarbonyl lysine (PABK), that possesses a panel of unique properties capable of fulfilling various protein manipulation purposes. In addition to being used as a bioorthogonal ligation handle, an infrared probe and ...[more]

PMID: 28451140

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