Cyclic dinucleotide detection with riboswitch-G-quadruplex hybrid.

Area of Science:

• Biochemistry
• Molecular Biology
• Biosensor Development

Background:

• Riboswitches are genetic সুইচ that regulate gene expression in response to small molecules.
• G-quadruplexes are non-canonical DNA secondary structures with diverse biological roles.
• Peroxidase mimics are synthetic catalysts that emulate the activity of natural peroxidases.

Purpose of the Study:

• To engineer a conditional riboswitch-peroxidase-mimicking sensor.
• To detect cyclic di-GMP (c-di-GMP) using a biosensor.
• To optimize the sensor's signal-to-noise ratio.

Main Methods:

• Fusion of a cyclic dinucleotide riboswitch with a G-quadruplex motif.
• Utilizing the sensor to oxidize colorimetric and fluorogenic substrates.
• Comparing the performance of two-floor versus three-floor split G-quadruplex structures.

Main Results:

• The fused riboswitch-G-quadruplex construct successfully mimicked peroxidase activity.
• The sensor detected the presence of c-di-GMP through substrate oxidation.
• A two-floor split G-quadruplex design significantly improved the signal-to-noise ratio compared to a three-floor design.

Conclusions:

• A novel conditional riboswitch-peroxidase-mimicking sensor for c-di-GMP detection has been developed.
• The sensor's performance can be enhanced by optimizing the G-quadruplex structure.
• This work provides a new tool for c-di-GMP sensing with improved signal fidelity.