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Protein recognition by bivalent, 'turn-on' fluorescent molecular probes.

ABSTRACT: We show that the conversion of a known intercalating dye (i.e., thiazole orange) into a bivalent protein binder could lead to the realization of a novel class of 'turn-on' fluorescent molecular probes that detect proteins with high affinity, selectivity, and a high signal-to-noise (S/N) ratio. The feasibility of the approach is demonstrated with monomolecular probes that light-up in the presence of three different proteins: acetylcholinesterase (AChE), glutathione-s-transferase (GST), or avidin (Av) at low concentrations and with minimal background signal. The way by which such probes can be used to detect individual protein isoforms and be applied in inhibitor screening, cell imaging, and biomarker detection is described.

SUBMITTER: Unger-Angel L

PROVIDER: S-EPMC5502391 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Protein recognition by bivalent, 'turn-on' fluorescent molecular probes.

Unger-Angel Linor L Rout Bhimsen B Ilani Tal T Eisenstein Miriam M Motiei Leila L Margulies David D

Chemical science 20150612 10

We show that the conversion of a known intercalating dye (i.e., thiazole orange) into a bivalent protein binder could lead to the realization of a novel class of 'turn-on' fluorescent molecular probes that detect proteins with high affinity, selectivity, and a high signal-to-noise (S/N) ratio. The feasibility of the approach is demonstrated with monomolecular probes that light-up in the presence of three different proteins: acetylcholinesterase (AChE), glutathione-s-t ...[more]

PMID: 28717444

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