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20  structures 5274  species 5  interactions 5292  sequences 2  architectures

Family: Fumarate_red_C (PF02300)

Summary: Fumarate reductase subunit C

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This is the Wikipedia entry entitled "Fumarate reductase". More...

Fumarate reductase Edit Wikipedia article

Fumarate reductase respiratory complex
PDB 2bs3 EBI.jpg
Structure of Quinol-Fumarate Reductase Flavoprotein Subunit A.[1]
Symbol Fum_red_TM
Pfam PF01127
Pfam clan CL0335
InterPro IPR004224
SCOP 1qla
OPM superfamily 3
OPM protein 2bs3
CDD cd03494
Fumarate reductase subunit C
PDB 1l0v EBI.jpg
quinol-fumarate reductase with menaquinol molecules
Symbol Fumarate_red_C
Pfam PF02300
Pfam clan CL0335
InterPro IPR003510
SCOP 1fum
CDD cd00546
Fumarate reductase subunit D
PDB 1kfy EBI.jpg
quinol-fumarate reductase with quinol inhibitor 2-[1-(4-chloro-phenyl)-ethyl]-4,6-dinitro-phenol
Symbol Fumarate_red_D
Pfam PF02313
Pfam clan CL0335
InterPro IPR003418
SCOP 1fum
CDD cd00547

Fumarate reductase is the enzyme that converts fumarate to succinate, and is important in microbial metabolism as a part of anaerobic respiration.[2]

Succinate + acceptor <=> fumarate + reduced acceptor

In other words, fumarate reductase couples the reduction of fumarate to succinate to the oxidation of quinol to quinone, in a reaction opposite to that catalysed by the related complex II of the respiratory chain (succinate dehydrogenase).[3]

Fumarate reductase complex includes four subunits.[4] Subunit A contains the site of fumarate reduction and a covalently bound flavin adenine dinucleotide prosthetic group. Subunit B contains three iron-sulphur centres. The menaquinol-oxidizing subunit C consists of five membrane-spanning, primarily helical segments and binds two haem b molecules.[3] The D subunit may be required to anchor the catalytic components of the fumarate reductase complex to the cytoplasmic membrane.

See also


  1. ^ Lancaster CR, Sauer US, Gross R et al. (December 2005). "Experimental support for the "E pathway hypothesis" of coupled transmembrane e- and H+ transfer in dihemic quinol:fumarate reductase". Proc. Natl. Acad. Sci. U.S.A. 102 (52): 18860–5. doi:10.1073/pnas.0509711102. PMC 1323215. PMID 16380425. 
  2. ^ Iverson TM, Luna-Chavez C, Cecchini G, Rees DC (1999). "Structure of the Escherichia coli fumarate reductase respiratory complex". Science 284 (5422): 1961–6. doi:10.1126/science.284.5422.1961. PMID 10373108. 
  3. ^ a b Michel H, Lancaster CR, Kroger A, Auer M (1999). "Structure of fumarate reductase from Wolinella succinogenes at 2.2 A resolution". Nature 402 (6760): 377–385. doi:10.1038/46483. PMID 10586875. 
  4. ^

External links

This article incorporates text from the public domain Pfam and InterPro IPR004224

This article incorporates text from the public domain Pfam and InterPro IPR003510

This article incorporates text from the public domain Pfam and InterPro IPR003418

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Fumarate reductase subunit C Provide feedback

Fumarate reductase is a membrane-bound flavoenzyme consisting of four subunits, A-B. A and B comprise the membrane-extrinsic catalytic domain and C and D link the catalytic centres to the electron-transport chain. This family consists of the 15kD hydrophobic subunit C.

Literature references

  1. Cole ST; , Eur J Biochem 1987;167:481-488.: Nucleotide sequence and comparative analysis of the frd operon encoding the fumarate reductase of Proteus vulgaris. Extensive sequence divergence of the membrane anchors and absence of an frd-linked ampC cephalosporinase gene. PUBMED:3308458 EPMC:3308458

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR003510

Fumarate reductase is a membrane-bound flavoenzyme consisting of four subunits, A-B. A and B comprise the membrane-extrinsic catalytic domain and C and D link the catalytic centres to the electron-transport chain. This family consists of the 15kDa hydrophobic subunit C.

Gene Ontology

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Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan FumRed-TM (CL0335), which has the following description:

This superfamily constitutes two distinct families: in one family the common fold is contained in a single-chain subunit, in the other it is formed by two chains.

The clan contains the following 5 members:

CybS DUF1691 Fumarate_red_C Fumarate_red_D Sdh_cyt


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Curation and family details

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Seed source: Pfam-B_11568 (release 5.2)
Previous IDs: none
Type: Domain
Author: Mian N, Bateman A
Number in seed: 43
Number in full: 5292
Average length of the domain: 125.70 aa
Average identity of full alignment: 61 %
Average coverage of the sequence by the domain: 97.56 %

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HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 80369284 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 24.2 24.2
Trusted cut-off 24.3 24.5
Noise cut-off 24.1 24.1
Model length: 127
Family (HMM) version: 13
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Species distribution

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There are 5 interactions for this family. More...

Fumarate_red_D Fer2_3 Fer4_8 FAD_binding_2 Succ_DH_flav_C


For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Fumarate_red_C domain has been found. There are 20 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.

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