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

Area of Science:

• Biochemistry and Molecular Biology
• Analytical Chemistry
• Biotechnology

Background:

• Fluorescent molecular probes are crucial for detecting biomolecules.
• Existing probes often suffer from low signal-to-noise ratios and poor selectivity.
• Developing 'turn-on' probes with enhanced detection capabilities is an ongoing challenge.

Purpose of the Study:

• To design and synthesize a new class of 'turn-on' fluorescent molecular probes.
• To demonstrate the probes' ability to detect proteins with high affinity and selectivity.
• To explore the application of these probes in various biological and diagnostic contexts.

Main Methods:

• Modification of a known intercalating dye (thiazole orange) into a bivalent protein binder.
• Synthesis of monomolecular probes.
• Validation of probe performance using specific proteins: acetylcholinesterase (AChE), glutathione-s-transferase (GST), and avidin (Av).

Main Results:

• The developed probes exhibit 'turn-on' fluorescence upon binding to target proteins.
• High affinity, selectivity, and signal-to-noise (S/N) ratios were achieved.
• Successful detection of AChE, GST, and Avidin at low concentrations with minimal background signal.

Conclusions:

• The conversion of thiazole orange into bivalent protein binders is a viable strategy for creating novel fluorescent probes.
• These probes offer a promising platform for sensitive and selective protein detection.
• Potential applications include protein isoform detection, inhibitor screening, cell imaging, and biomarker detection.