Development of Malate Biosensor-Containing Hydrogels and Living Cell-Based Sensors

Area of Science:

• Biotechnology
• Biochemistry
• Bioengineering

Background:

• Malate is a crucial intermediate in the citric acid cycle, vital for cellular energy metabolism.
• The citric acid cycle has applications in biofuel cell development.
• Real-time sensing of malate is needed for various biological and bioelectronic applications.

Purpose of the Study:

• To engineer a genetically encoded, protein-based fluorescent biosensor for real-time malate detection.
• To create a biosensor responsive specifically to malate.
• To demonstrate the utility of the biosensor in monitoring enzymatic reactions and in biomaterials.

Main Methods:

• Structure-based mutagenesis of a Citron GFP-based biosensor.
• Engineering a fluorescent biosensor named Malon.
• Incorporation of Malon into redox polymer hydrogels and bacterial cells.

Main Results:

• Malon exhibits high specificity and fluorescence activation in response to malate.
• Malon successfully monitored enzymatic reactions in vitro.
• Malate levels were analyzed in redox polymer hydrogels and living bacterial cells using Malon.

Conclusions:

• Malon is a novel, genetically encoded fluorescent biosensor for malate.
• The biosensor enables real-time monitoring of enzymatic cascades within biomaterials and living systems.
• Malon presents a promising tool for bioelectronic devices and metabolic engineering.