A fluorescence resonance energy transfer sensor based on maltose binding protein

Area of Science:

• Biochemistry
• Analytical Chemistry
• Molecular Biology

Background:

• Maltose is a crucial disaccharide in biological systems.
• Accurate detection of maltose is vital for various research and diagnostic applications.
• Existing maltose detection methods may lack sensitivity or require complex procedures.

Purpose of the Study:

• To develop a novel, highly sensitive fluorescence resonance energy-transfer (FRET) based sensing system for maltose detection.
• To utilize the E. coli maltose binding protein (MBP) as a core component for maltose recognition.
• To establish a FRET system that provides a direct fluorescence change upon maltose binding.

Main Methods:

• Engineered E. coli maltose binding protein (MBP) as the FRET donor, modified with cyanine dyes (Cy3 or Cy3.5).
• Developed a novel FRET acceptor using beta-cyclodextrin (beta-CD) conjugated with either Cy5 or QSY9.
• Assembled the FRET complex through the binding of beta-CD-dye to dye-conjugated MBP.
• Disrupted the FRET complex by adding maltose, leading to a measurable change in donor fluorescence.

Main Results:

• Successfully demonstrated a FRET sensing system for maltose detection.
• Estimated maltose dissociation values for MBP in the range of 0.14–2.90 µM.
• Achieved maltose limits of detection between 50–100 nm, indicating high sensitivity.

Conclusions:

• The developed FRET system based on MBP and beta-CD is effective for sensitive maltose detection.
• The system provides a direct fluorescence readout, simplifying maltose quantification.
• This approach offers a promising tool for studying maltose-related biological processes.