C4-dicarboxylate anaerobic carrier-like (IPR018385)

Short name: C4_dicarb_anaerob_car-like

Overlapping homologous superfamilies


Family relationships


Escherichia coli contains four different secondary carriers (DcuA, DcuB, DcuC, and DctA) for C4-dicarboxylates [PMID: 10482502, PMID: 1512189, PMID: 7961398, PMID: 8955408] DcuA is used for aerobic growth on C4-dicarboxylates [PMID: 10482502, PMID: 5541510], whereas the Dcu carriers (encoded by the dcuA, dcuB, and dcuC genes) are used under anaerobic conditions and form a distinct family of carriers [PMID: 1512189, PMID: 8020497, PMID: 9889977, PMID: 7961398, PMID: 9230919, PMID: 8955408]. Each of the Dcu carriers is able to catalyze the uptake, antiport, and possibly also efflux of C4-dicarboxylates. DcuB is the major C4-dicarboxylate carrier for fumarate respiration with high fumarate-succinate exchange activity. It is synthesized only in the absence of oxygen and nitrate and in the presence of C4-dicarboxylates [PMID: 1512189, PMID: 9973351, PMID: 9852003, PMID: 9765574]. DcuA is expressed constitutively in aerobic and anaerobic growth and can substitute for DcuB [PMID: 9852003, PMID: 7961398]. These proteins are members of the C4-dicarboxylate Uptake C (DcuC) family. DcuC has 12 GES predicted transmembrane regions, is induced only under anaerobic conditions, and is not repressed by glucose. DcuC may therefore function as a succinate efflux system during anaerobic glucose fermentation. However, when overexpressed, it can replace either DcuA or DcuB in catalyzing fumarate-succinate exchange and fumarate uptake [PMID: 8020497, PMID: 10368146]. DcuC shows the same transport modes as DcuA and DcuB (exchange, uptake, and presumably efflux of C4-dicarboxylates) [PMID: 8955408].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0016021 integral component of membrane

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.