DcuC family explained

Symbol:	DcuC
C4-dicarboxylate anaerobic carrier
Pfam:	PF03606
Pfam Clan:	CL0182
Tcdb:	9.B.50
Interpro:	IPR018385

The C₄-dicarboxylate uptake C family or DcuC family (TC# 2.A.61) is a family of transmembrane ion transporters found in bacteria.^[1] A representative list of proteins belonging to the DcuC family can be found in the Transporter Classification Database.

An anaerobic C₄-dicarboxylate transporter (DcuC) of E. coli (TC# 2.A.61.1.1) has 14 putative 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 catalysing fumarate-succinate exchange and fumarate uptake.^{[2] [3]} DcuC shows the same transport modes as DcuA and DcuB (exchange, uptake, and presumably efflux of C4-dicarboxylates).^{[4] [5]}

The reactions probably catalyzed by the E. coli DcuC protein are:

1. C₄-dicarboxylate (out) + nH+ (out) → C₄-dicarboxylate (in) + nH+ (in)
2. C₄-dicarboxylate₁ (out) + C₄-dicarboxylate₂ (in) ⇌ C₄-dicarboxylate₁ (in) + C₄-dicarboxylate₂ (out).

See also

• • Dicarboxylate Dcu family

Notes and References

1. Prakash. Shraddha. Cooper. Garret. Singhi. Soumya. Saier. Milton H.. 2003-12-03. The ion transporter superfamily. Biochimica et Biophysica Acta (BBA) - Biomembranes. 1618. 1. 79–92. 0006-3002. 14643936. 10.1016/j.bbamem.2003.10.010.
2. June 1994. Transport of C4-dicarboxylates by anaerobically grown Escherichia coli. Energetics and mechanism of exchange, uptake and efflux. Eur. J. Biochem.. 222. 2. 605–14. 10.1111/j.1432-1033.1994.tb18903.x. 8020497. Engel P, Kramer R, Unden G . free.
3. June 1999. Functioning of DcuC as the C4-dicarboxylate carrier during glucose fermentation by Escherichia coli. J. Bacteriol.. 181. 12. 3716–20. 10.1128/JB.181.12.3716-3720.1999. 93849. 10368146. Zientz E, Janausch IG, Six S, Unden G .
4. December 1996. Identification of a third secondary carrier (DcuC) for anaerobic C4-dicarboxylate transport in Escherichia coli: roles of the three Dcu carriers in uptake and exchange. J. Bacteriol.. 178. 24. 7241–7. 10.1128/jb.178.24.7241-7247.1996 . 178639. 8955408. Zientz E, Six S, Unden G .
5. Web site: 2.A.61 The C4-dicarboxylate Uptake C (DcuC) Family. Transporter Classification Database. 2016-03-04.