Quantitative analyses of individual sugars in mixture using FRET-based biosensors

Area of Science:

• Molecular biology
• Biotechnology
• Analytical chemistry

Background:

• Accurate measurement of individual sugars in complex biological mixtures is crucial for understanding metabolic processes.
• Existing methods for sugar analysis can be time-consuming or lack specificity.
• Development of rapid, sensitive, and specific biosensors is needed for real-time monitoring.

Purpose of the Study:

• To engineer and validate novel molecular biosensors for the detection of specific individual sugars.
• To apply these biosensors for monitoring sugar consumption in bacterial culture broths.
• To compare the performance of the developed biosensors with established analytical techniques.

Main Methods:

• Selection of four sugar-binding proteins (SBPs) from Escherichia coli for allose, arabinose, ribose, and glucose.
• Construction of Förster Resonance Energy Transfer (FRET)-based biosensors by linking SBPs to cyan and yellow fluorescent proteins (CFP-L-SBP-YFP).
• Randomization of linker regions and screening for optimal sensor performance, followed by specificity testing with 16 different sugars.

Main Results:

• Four functional sugar biosensors were successfully developed for allose, arabinose, ribose, and glucose.
• The sensors demonstrated high specificity for their target sugars.
• Apparent dissociation constants (Kd) were determined to be in the low micromolar range (0.17–0.36 μM).
• Application in E. coli culture broths showed good correlation with High-Performance Liquid Chromatography (HPLC) results for sugar consumption monitoring.

Conclusions:

• The developed FRET-based molecular biosensors are effective tools for quantifying individual sugars in biological samples.
• These biosensors offer a rapid, user-friendly, and accurate alternative to traditional sugar analysis methods.
• The technology holds promise for applications in metabolic engineering, microbial physiology studies, and bioprocess monitoring.