An L-2-hydroxyglutarate biosensor based on specific transcriptional regulator LhgR

Area of Science:

• Biochemistry
• Molecular Biology
• Microbiology

Background:

• L-2-Hydroxyglutarate (L-2-HG) is crucial in physiological processes like tumorigenesis and hypoxic adaptation.
• Regulation of L-2-HG metabolism is poorly understood, with no specific L-2-HG responders identified previously.

Purpose of the Study:

• To identify a specific regulator of L-2-HG metabolism.
• To develop a novel biosensor for detecting L-2-HG concentrations.

Main Methods:

• Bacterial genomic neighborhood analysis to identify L-2-HG responsive genes.
• Characterization of LhgR as an allosteric transcription factor binding L-2-HG.
• Construction of a Förster Resonance Energy Transfer (FRET) based L-2-HG sensor.

Main Results:

• LhgR was identified as a transcriptional repressor of L-2-HG oxidase (LhgO) in Pseudomonas putida.
• LhgR specifically recognizes and binds L-2-HG as its effector molecule.
• A functional L-2-HG-sensing FRET sensor was successfully constructed and validated.
• The sensor detected bacterial L-2-HG during carbon starvation and revealed hypoxia-induced L-2-HG accumulation in human cells.

Conclusions:

• LhgR is the first identified specific L-2-HG responsive regulator.
• The developed FRET sensor provides a valuable tool for monitoring L-2-HG in diverse biological contexts.
• This work advances the understanding of L-2-HG metabolic regulation and its role in cellular processes.