1 research outputs found
Diels–Alder Cycloaddition for Fluorophore Targeting to Specific Proteins inside Living Cells
The inverse-electron-demand Diels–Alder cycloaddition
between <i>trans</i>-cyclooctenes and tetrazines is biocompatible
and exceptionally
fast. We utilized this chemistry for site-specific fluorescence labeling
of proteins on the cell surface and inside living mammalian cells
by a two-step protocol. <i>Escherichia coli</i> lipoic acid
ligase site-specifically ligates a <i>trans</i>-cyclooctene
derivative onto a protein of interest in the first step, followed
by chemoselective derivatization with a tetrazine–fluorophore
conjugate in the second step. On the cell surface, this labeling was
fluorogenic and highly sensitive. Inside the cell, we achieved specific
labeling of cytoskeletal proteins with green and red fluorophores.
By incorporating the Diels–Alder cycloaddition, we have broadened
the panel of fluorophores that can be targeted by lipoic acid ligase