Summary: Anaerobic c4-dicarboxylate membrane transporter
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Anaerobic C4-dicarboxylate membrane transporter protein Edit Wikipedia article
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|Anaerobic c4-dicarboxylate membrane transporter|
|C4-dicarboxylate anaerobic carrier|
In molecular biology, the anaerobic C4-dicarboxylate membrane transporter protein family (or C4-dicarboxylate Uptake (Dcu) family) is a family of proteins which includes the DcuA, DcuB and DcuC proteins. Many members of this family are predicted to have 12 GES predicted transmembrane regions, however the one member of this family whose membrane topology has been experimentally determined has 10 transmembrane regions, with both the N- and C-termini localized to the periplasm.
The DcuA and DcuB proteins are involved in the transport of aspartate, malate, fumarate and succinate in many species and are thought to function as antiporters with any two of these substrates. Since DcuA is encoded in an operon with the gene for aspartase, and DcuB is encoded in an operon with the gene for fumarase, their physiological functions may be to catalyse aspartate:fumarate and fumarate:malate exchange during the anaerobic utilization of aspartate and fumarate, respectively. The Escherichia coli DcuA and DcuB proteins have very different expression patterns. DcuA is constitutively expressed; DcuB is strongly induced anaerobically by FNR and C4-dicarboxylates, while it is repressed by nitrate and subject to CRP-mediated catabolite repression. 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. DcuA is expressed constitutively in aerobic and anaerobic growth and can substitute for DcuB.
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 catalysing fumarate-succinate exchange and fumarate uptake. DcuC shows the same transport modes as DcuA and DcuB (exchange, uptake, and presumably efflux of C4-dicarboxylates).
- Golby P, Kelly DJ, Guest JR, Andrews SC (September 1998). "Topological analysis of DcuA, an anaerobic C4-dicarboxylate transporter of Escherichia coli". J. Bacteriol. 180 (18): 4821–7. PMC 107505. PMID 9733683.
- Six S, Andrews SC, Roberts RE, Unden G, Guest JR (November 1993). "Construction and properties of Escherichia coli mutants defective in two genes encoding homologous membrane proteins with putative roles in anaerobic C4-dicarboxylic acid transport". Biochem. Soc. Trans. 21 (4): 342S. PMID 8131924.
- Nogrady N, Imre A, Rychlik I, Barrow PA, Nagy B (December 2003). "Genes responsible for anaerobic fumarate and arginine metabolism are involved in growth suppression in Salmonella enterica serovar Typhimurium in vitro, without influencing colonisation inhibition in the chicken in vivo". Vet. Microbiol. 97 (3-4): 191–9. doi:10.1016/j.vetmic.2003.08.011. PMID 14654290.
- Ullmann R, Gross R, Simon J, Unden G, Kroger A (October 2000). "Transport of C(4)-dicarboxylates in Wolinella succinogenes". J. Bacteriol. 182 (20): 5757–64. doi:10.1128/jb.182.20.5757-5764.2000. PMC 94697. PMID 11004174.
- Six S, Andrews SC, Unden G, Guest JR (November 1994). "Escherichia coli possesses two homologous anaerobic C4-dicarboxylate membrane transporters (DcuA and DcuB) distinct from the aerobic dicarboxylate transport system (Dct)". J. Bacteriol. 176 (21): 6470–8. PMC 197000. PMID 7961398.
- Golby P, Kelly DJ, Guest JR, Andrews SC (December 1998). "Transcriptional regulation and organization of the dcuA and dcuB genes, encoding homologous anaerobic C4-dicarboxylate transporters in Escherichia coli". J. Bacteriol. 180 (24): 6586–96. PMC 107762. PMID 9852003.
- Engel P, Kramer R, Unden G (September 1992). "Anaerobic fumarate transport in Escherichia coli by an fnr-dependent dicarboxylate uptake system which is different from the aerobic dicarboxylate uptake system". J. Bacteriol. 174 (17): 5533–9. PMC 206496. PMID 1512189.
- Golby P, Davies S, Kelly DJ, Guest JR, Andrews SC (February 1999). "Identification and characterization of a two-component sensor-kinase and response-regulator system (DcuS-DcuR) controlling gene expression in response to C4-dicarboxylates in Escherichia coli". J. Bacteriol. 181 (4): 1238–48. PMC 93502. PMID 9973351.
- Zientz E, Bongaerts J, Unden G (October 1998). "Fumarate regulation of gene expression in Escherichia coli by the DcuSR (dcuSR genes) two-component regulatory system". J. Bacteriol. 180 (20): 5421–5. PMC 107591. PMID 9765574.
- Engel P, Kramer R, Unden G (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. doi:10.1111/j.1432-1033.1994.tb18903.x. PMID 8020497.
- Zientz E, Janausch IG, Six S, Unden G (June 1999). "Functioning of DcuC as the C4-dicarboxylate carrier during glucose fermentation by Escherichia coli". J. Bacteriol. 181 (12): 3716–20. PMC 93849. PMID 10368146.
- Zientz E, Six S, Unden G (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. PMC 178639. PMID 8955408.
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Internal database links
|Similarity to PfamA using HHSearch:||DcuC|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR004668
These proteins are members of the C4-Dicarboxylate Uptake (Dcu) family. Most proteins in this family are predicted to have 12 GES predicted transmembrane regions; however the one member whose membrane topology has been experimentally determined has 10 transmembrane regions, with both the N- and C-termini localized to the periplasm [PUBMED:9733683]. The DcuA and DcuB proteins are involved in the transport of aspartate, malate, fumarate and succinate in many species [PUBMED:8131924, PUBMED:14654290, PUBMED:11004174], and are thought to function as antiporters with any two of these substrates. Since DcuA is encoded in an operon with the gene for aspartase, and DcuB is encoded in an operon with the gene for fumarase, their physiological functions may be to catalyze aspartate:fumarate and fumarate:malate exchange during the anaerobic utilization of aspartate and fumarate, respectively [PUBMED:7961398]. The Escherichia coli DcuA and DcuB proteins have very different expression patterns [PUBMED:9852003]. DcuA is constitutively expressed; DcuB is strongly induced anaerobically by FNR and C4-dicarboxylates, while it is repressed by nitrate and subject to CRP-mediated catabolite repression.
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||integral component of membrane (GO:0016021)|
|Molecular function||C4-dicarboxylate transmembrane transporter activity (GO:0015556)|
|Biological process||C4-dicarboxylate transport (GO:0015740)|
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This superfamily of secondary carriers specific for cationic and anionic compounds, has been termed the ion transporter (IT) superfamily .
The clan contains the following 19 members:ABG_transport ArsB CitMHS CitMHS_2 DctM DcuA_DcuB DcuC DUF1646 DUF401 EXS GntP_permease Lactate_perm MatC_N Na_H_antiport_2 Na_H_antiport_3 Na_H_antiporter Na_sulph_symp NhaB SCFA_trans
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|Author:||TIGRFAMs, Griffiths-Jones SR|
|Number in seed:||122|
|Number in full:||350|
|Average length of the domain:||346.00 aa|
|Average identity of full alignment:||40 %|
|Average coverage of the sequence by the domain:||82.95 %|
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build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 11927849 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||11|
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