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bioRxiv · 10.1101/2020.07.07.187567

A fluorescent L-2-hydroxyglutarate biosensor

Kang, Z.·Zhang, M.·Gao, K.·Zhang, W.·Liu, Y.·Xiao, D.·Guo, S.·Ma, C.·Gao, C.·Xu, P.
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Abstract

L-2-Hydroxyglutarate (L-2-HG) plays important roles in diverse physiological processes, such as carbon starvation response, tumorigenesis, and hypoxic adaptation. Despite its importance and intensively studied metabolism, regulation of L-2-HG metabolism remains poorly understood and a regulator specifically responded to L-2-HG has never been identified. Based on the genomic neighborhood analysis of the gene encoding L-2-HG oxidase (LhgO), LhgR, which represses the transcription of lhgO, was identified in Pseudomonas putida W619 in this study. LhgR was demonstrated to recognize L-2-HG as its specific effector molecule, and this allosteric transcription factor was then used as a biorecognition element for construction of L-2-HG-sensing FRET sensor. The newly developed L-2-HG sensor can conveniently monitor the concentrations of L-2-HG in various biological samples. In addition to bacterial L-2-HG generation during carbon starvation, biological functions of the L-2-HG dehydrogenase and hypoxia induced L-2-HG accumulation were also revealed by using the L-2-HG sensor in human cells.Competing Interest StatementThe authors have declared no competing interest.View Full Text

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Kang, Z., Zhang, M., Gao, K., Zhang, W., Liu, Y., Xiao, D., Guo, S., Ma, C., Gao, C., Xu, P.. 2020-07-07. A fluorescent L-2-hydroxyglutarate biosensor. https://doi.org/10.1101/2020.07.07.187567

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