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bioRxiv · 10.1101/2021.03.01.433382

C4-dicarboxylate metabolons: Interaction of C4-dicarboxylate transporters of Escherichia coli with cytosolic enzymes and regulators

Schubert, C.·Unden, G.
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Abstract

Metabolons represent the structural organization of proteins for metabolic or regulatory pathways. Here the interaction of enzymes fumarase FumB and aspartase AspA with the C4-DC transporters DcuA and DcuB of Escherichia coli was tested by a bacterial two-hybrid (BACTH) assay in situ, or by co-chromatography (mSPINE). DcuB interacted strongly with FumB and AspA, and DcuA with AspA. The fumB-dcuB and the dcuA-aspA genes encoding the respective proteins are known for their colocalization on the genome and the production of co-transcripts. The data consistently suggest the formation of DcuB/FumB, DcuB/AspA and DcuA/AspA metabolons in fumarate respiration for the uptake of L-malate, or L-aspartate, conversion to fumarate and excretion of succinate after reduction. The DcuA/AspA metabolon catalyzes L-Asp uptake and fumarate excretion in concerted action also to provide ammonia for nitrogen assimilation.

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Schubert, C., Unden, G.. 2021-03-01. C4-dicarboxylate metabolons: Interaction of C4-dicarboxylate transporters of Escherichia coli with cytosolic enzymes and regulators. https://doi.org/10.1101/2021.03.01.433382

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