A cell-penetrating artificial metalloenzyme regulates a gene switch in a designer mammalian cell

• DOI: 10.1038/s41467-018-04440-0
• Publication Date: 2018-05-10T10:06:26Z
• Authors: Yasunori Okamoto; Ryosuke Kojima; Fabian Schwizer; Eline Bartolami; Tillmann Heinisch; Stefan Matile; Martin Fussenegger; Thomas R. Ward
• Keywords: info:eu-repo/classification/ddc/540; Molecular Structure; Science; Q; Biotin; Metalloendopeptidases; Stereoisomerism; 01 natural sciences; Article; Catalysis; Ruthenium; 0104 chemical sciences; 3. Good health; HEK293 Cells; ddc:540; Humans; Point Mutation; Triiodothyronine; Biotinylation; Streptavidin

AbstractComplementing enzymes in their native environment with either homogeneous or heterogeneous catalysts is challenging due to the sea of functionalities present within a cell. To supplement these efforts, artificial metalloenzymes are drawing attention as they combine attractive features of both homogeneous catalysts and enzymes. Herein we show that such hybrid catalysts consisting of a metal cofactor, a cell-penetrating module, and a protein scaffold are taken up into HEK-293T cells where they catalyze the uncaging of a hormone. This bioorthogonal reaction causes the upregulation of a gene circuit, which in turn leads to the expression of a nanoluc-luciferase. Relying on the biotin–streptavidin technology, variation of the biotinylated ruthenium complex: the biotinylated cell-penetrating poly(disulfide) ratio can be combined with point mutations on streptavidin to optimize the catalytic uncaging of an allyl-carbamate-protected thyroid hormone triiodothyronine. These results demonstrate that artificial metalloenzymes offer highly modular tools to perform bioorthogonal catalysis in live HEK cells.