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23  structures 6788  species 0  interactions 10857  sequences 56  architectures

Family: ETF_alpha (PF00766)

Summary: Electron transfer flavoprotein FAD-binding domain

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

This is the Wikipedia entry entitled "Electron-transferring flavoprotein". More...

Electron-transferring flavoprotein Edit Wikipedia article

Electron transfer flavoproteins (ETFs) serve as specific electron acceptors for primary dehydrogenases, transferring the electrons to terminal respiratory systems such as electron-transferring-flavoprotein dehydrogenase. They can be functionally classified into constitutive, "housekeeping" ETFs, mainly involved in the oxidation of fatty acids (Group I), and ETFs produced by some prokaryotes under specific growth conditions, receiving electrons only from the oxidation of specific substrates (Group II).[1]

ETFs are heterodimeric proteins composed of an alpha and beta subunit, and contain an FAD cofactor and AMP.[2][3] ETF consists of three domains: domains I and II are formed by the N- and C-terminal portions of the alpha subunit, respectively, while domain III is formed by the beta subunit. Domains I and III share an almost identical alpha-beta-alpha sandwich fold, while domain II forms an alpha-beta-alpha sandwhich similar to that of bacterial flavodoxins. FAD is bound in a cleft between domains II and III, while domain III binds the AMP molecule. Interactions between domains I and III stabilise the protein, forming a shallow bowl where domain II resides.

See also

References

  1. ^ Weidenhaupt M, Rossi P, Beck C, Fischer HM, Hennecke H (1996). "Bradyrhizobium japonicum possesses two discrete sets of electron transfer flavoprotein genes: fixA, fixB and etfS, etfL". Arch. Microbiol. 165 (3): 169–78. PMID 8599534.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ Tsai MH, Saier MH (1995). "Phylogenetic characterization of the ubiquitous electron transfer flavoprotein families ETF-alpha and ETF-beta". Res. Microbiol. 146 (5): 397–404. PMID 8525056.
  3. ^ Roberts DL, Frerman FE, Kim JJ (1996). "Three-dimensional structure of human electron transfer flavoprotein to 2.1-A resolution". Proc. Natl. Acad. Sci. U.S.A. 93 (25): 14355–60. PMID 8962055.{{cite journal}}: CS1 maint: multiple names: authors list (link)

External links

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.

Electron transfer flavoprotein FAD-binding domain Provide feedback

This domain found at the C-terminus of electron transfer flavoprotein alpha chain and binds to FAD [1]. The fold consists of a five-stranded parallel beta sheet as the core of the domain, flanked by alternating helices. A small part of this domain is donated by the beta chain [1].

Literature references

  1. Roberts DL, Frerman FE, Kim JJ; , Proc Natl Acad Sci U S A 1996;93:14355-14360.: Three-dimensional structure of human electron transfer flavoprotein to 2.1-A resolution. PUBMED:8962055 EPMC:8962055


External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR014731

Electron transfer flavoproteins (ETFs) serve as specific electron acceptors for primary dehydrogenases, transferring the electrons to terminal respiratory systems. They can be functionally classified into constitutive, "housekeeping" ETFs, mainly involved in the oxidation of fatty acids (Group I), and ETFs produced by some prokaryotes under specific growth conditions, receiving electrons only from the oxidation of specific substrates (Group II) [ PUBMED:8599534 ].

ETFs are heterodimeric proteins composed of an alpha and beta subunit, and contain an FAD cofactor and AMP [ PUBMED:2326318 , PUBMED:8525056 , PUBMED:8962055 , PUBMED:10026281 , PUBMED:12567183 ]. ETF consists of three domains: domains I and II are formed by the N- and C-terminal portions of the alpha subunit, respectively, while domain III is formed by the beta subunit. Domains I and III share an almost identical alpha-beta-alpha sandwich fold, while domain II forms an alpha-beta-alpha sandwich similar to that of bacterial flavodoxins. FAD is bound in a cleft between domains II and III, while domain III binds the AMP molecule. Interactions between domains I and III stabilise the protein, forming a shallow bowl where domain II resides.

This entry represents the C-terminal domain of the alpha subunit of both Group I and Group II ETFs.

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 FAD_DHS (CL0085), which has the following description:

The members of this family adopt a Rossmann fold, similar to CLAN:CL0063. However, the members of this family are distinguished in that the FAD/NAD cofactor is bound in the opposite direction. In this arrangement, the adenosine moiety is found bound at the second half of the fold. In addition, the conserved GxGxxG motif found in classical NADP binding Rossmann folds is absent. Finally, another distinguishing characteristic is the formation of an internal hydrogen bond in the FAD molecule [1].

The clan contains the following 10 members:

CO_dh DS DUF4917 ETF_alpha PNTB PPS_PS SIR2 SIR2_2 TPP_enzyme_M TPP_enzyme_M_2

Alignments

We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

View options

We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

  Seed
(427)
Full
(10857)
Representative proteomes UniProt
(50055)
RP15
(1460)
RP35
(5148)
RP55
(10898)
RP75
(18670)
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PP/heatmap 1            

1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

  Seed
(427)
Full
(10857)
Representative proteomes UniProt
(50055)
RP15
(1460)
RP35
(5148)
RP55
(10898)
RP75
(18670)
Alignment:
Format:
Order:
Sequence:
Gaps:
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Download options

We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

  Seed
(427)
Full
(10857)
Representative proteomes UniProt
(50055)
RP15
(1460)
RP35
(5148)
RP55
(10898)
RP75
(18670)
Raw Stockholm Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download  

You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

HMM logo

HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...

Trees

This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

Note: You can also download the data file for the tree.

Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Pfam-B_853 (release 2.1) & Pfam-B_1321 (release 3.0)
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Bateman A
Number in seed: 427
Number in full: 10857
Average length of the domain: 80.5 aa
Average identity of full alignment: 57 %
Average coverage of the sequence by the domain: 24.14 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 27.0 27.0
Trusted cut-off 27.2 27.0
Noise cut-off 26.8 26.9
Model length: 81
Family (HMM) version: 22
Download: download the raw HMM for this family

Species distribution

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Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence

Selections

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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

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Structures

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 ETF_alpha domain has been found. There are 23 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 sequence.

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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
A0A044S2G5 View 3D Structure Click here
A0A077ZCN0 View 3D Structure Click here
A0A0D2G6M2 View 3D Structure Click here
A0A0K0EJN5 View 3D Structure Click here
A0A0K0J075 View 3D Structure Click here
A0A0N4UP90 View 3D Structure Click here
A0A0R0H4V4 View 3D Structure Click here
A0A150ASU2 View 3D Structure Click here
A0A1C1CHE9 View 3D Structure Click here
A0A1D6H8R4 View 3D Structure Click here
A0A1D8PQF9 View 3D Structure Click here
A0A3P7DGF4 View 3D Structure Click here
A2XNR6 View 3D Structure Click here
A4I3J0 View 3D Structure Click here
B4F8E3 View 3D Structure Click here
C0ND48 View 3D Structure Click here
C1GNS8 View 3D Structure Click here
H6LGM8 View 3D Structure Click here
I1KEH3 View 3D Structure Click here
K0F3S9 View 3D Structure Click here
O33096 View 3D Structure Click here
P09819 View 3D Structure Click here
P0CN60 View 3D Structure Click here
P10449 View 3D Structure Click here
P13803 View 3D Structure Click here
P13804 View 3D Structure Click here
P26483 View 3D Structure Click here
P31574 View 3D Structure Click here
P52039 View 3D Structure Click here
P53573 View 3D Structure Click here
P59675 View 3D Structure Click here
P64095 View 3D Structure Click here
P71153 View 3D Structure Click here
P77378 View 3D Structure Click here
P78790 View 3D Structure Click here
P94551 View 3D Structure Click here
P9WNG9 View 3D Structure Click here
Q0AZ33 View 3D Structure Click here
Q12480 View 3D Structure Click here
Q2KJE4 View 3D Structure Click here