Powering down the Pfam website
On October 5th, we began redirecting traffic from Pfam (pfam.xfam.org) to InterPro (www.ebi.ac.uk/interpro). The Pfam website will remain available at pfam-legacy.xfam.org until January 2023, when it will be decommissioned. You can read more about the sunset period in our blog post.

Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
470  structures 8868  species 0  interactions 159100  sequences 969  architectures

Family: ABC_membrane (PF00664)

Summary: ABC transporter transmembrane region

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 "Transmembrane domain of ABC transporters". More...

Transmembrane domain of ABC transporters Edit Wikipedia article

ABC transporter transmembrane region
OPM superfamily18
OPM protein1pf4

ABC transporter transmembrane domain is main transmembrane structural unit of ABC transporters which consist of six transmembrane helixes. Many members of the ABC transporter family (Pfam PF00005) have two such regions.

Human proteins containing this domain



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.

ABC transporter transmembrane region Provide feedback

This family represents a unit of six transmembrane helices. Many members of the ABC transporter family (PF00005) have two such regions.

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR011527

This entry represents the transmembrane domain in cases where the TMD and ABC region are found in the same protein, and corresponds to ABC type 1 from Transporter Classification Database (http://www.tcdb.org/tcdb/index.php?tc=3.A.1).

ABC transporters minimally contain two conserved regions: a highly conserved ATP binding cassette (ABC) and a less conserved transmembrane domain (TMD). In certain bacterial transporters, these regions are found on different polypeptides. The function of the integral inner-membrane protein is to translocate the substrate across the membrane, as well as in substrate recognition [ PUBMED:9873074 , PUBMED:10529352 ].

ABC transporters belong to the ATP-Binding Cassette (ABC) superfamily, which uses the hydrolysis of ATP to energise diverse biological systems. ABC transporters minimally consist of two conserved regions: a highly conserved ATP binding cassette (ABC) and a less conserved transmembrane domain (TMD). These can be found on the same protein or on two different ones. Most ABC transporters function as a dimer and therefore are constituted of four domains, two ABC modules and two TMDs.

ABC transporters are involved in the export or import of a wide variety of substrates ranging from small ions to macromolecules. The major function of ABC import systems is to provide essential nutrients to bacteria. They are found only in prokaryotes and their four constitutive domains are usually encoded by independent polypeptides (two ABC proteins and two TMD proteins). Prokaryotic importers require additional extracytoplasmic binding proteins (one or more per systems) for function. In contrast, export systems are involved in the extrusion of noxious substances, the export of extracellular toxins and the targeting of membrane components. They are found in all living organisms and in general the TMD is fused to the ABC module in a variety of combinations. Some eukaryotic exporters encode the four domains on the same polypeptide chain [ PUBMED:9873074 ].

The ATP-Binding Cassette (ABC) superfamily forms one of the largest of all protein families with a diversity of physiological functions [ PUBMED:9873074 ]. Several studies have shown that there is a correlation between the functional characterisation and the phylogenetic classification of the ABC cassette [ PUBMED:9873074 , PUBMED:11421270 ]. More than 50 subfamilies have been described based on a phylogenetic and functional classification [ PUBMED:9873074 , PUBMED:11421269 , PUBMED:11421270 ]; (for further information see http://www.tcdb.org/tcdb/index.php?tc=3.A.1).

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

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

Loading domain graphics...

Pfam Clan

This family is a member of clan ABC_membrane (CL0241), which has the following description:

This clan includes families that are the membrane components of ABC transporter complexes. In general these regions are composed of six transmembrane helices [1].

The clan contains the following 4 members:

ABC_membrane ABC_membrane_2 ABC_membrane_3 SbmA_BacA


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.

Representative proteomes UniProt
Jalview View  View  View  View  View  View  View 
HTML View             
PP/heatmap 1            

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

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

Format an alignment

Representative proteomes UniProt

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.

Representative proteomes UniProt
Raw Stockholm Download     Download   Download        
Gzipped 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...


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_2 (release 2.1)
Previous IDs: none
Type: Family
Sequence Ontology: SO:0100021
Author: Bateman A
Number in seed: 70
Number in full: 159100
Average length of the domain: 261.8 aa
Average identity of full alignment: 14 %
Average coverage of the sequence by the domain: 40.21 %

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 28.0 21.7
Trusted cut-off 28.0 21.7
Noise cut-off 27.9 21.6
Model length: 274
Family (HMM) version: 26
Download: download the raw HMM for this family

Species distribution

Sunburst controls


Weight segments by...

Change the size of the sunburst


Colour assignments

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


Generate a FASTA-format file

Clear selection

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...

Loading sunburst data...

Tree controls


The tree shows the occurrence of this domain across different species. More...


Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.


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 ABC_membrane domain has been found. There are 470 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.

Loading structure mapping...

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
A0A044QP71 View 3D Structure Click here
A0A044QT19 View 3D Structure Click here
A0A044QUR1 View 3D Structure Click here
A0A044SII3 View 3D Structure Click here
A0A044SL67 View 3D Structure Click here
A0A044U7W4 View 3D Structure Click here
A0A044V9L6 View 3D Structure Click here
A0A059JJ46 View 3D Structure Click here
A0A059JK44 View 3D Structure Click here
A0A077YYN5 View 3D Structure Click here
A0A077YYV3 View 3D Structure Click here
A0A077Z192 View 3D Structure Click here
A0A077Z1D9 View 3D Structure Click here
A0A077Z1W2 View 3D Structure Click here
A0A077ZA50 View 3D Structure Click here
A0A077ZAZ4 View 3D Structure Click here
A0A077ZB46 View 3D Structure Click here
A0A077ZBW2 View 3D Structure Click here
A0A077ZBZ1 View 3D Structure Click here
A0A077ZG36 View 3D Structure Click here
A0A077ZGZ8 View 3D Structure Click here
A0A077ZH86 View 3D Structure Click here
A0A077ZHX9 View 3D Structure Click here
A0A095C325 View 3D Structure Click here
A0A0D1BUH6 View 3D Structure Click here
A0A0D1CZ63 View 3D Structure Click here
A0A0D2DF15 View 3D Structure Click here
A0A0D2DF32 View 3D Structure Click here
A0A0D2DIY6 View 3D Structure Click here
A0A0D2DUF5 View 3D Structure Click here
A0A0D2DZ04 View 3D Structure Click here
A0A0D2EL45 View 3D Structure Click here
A0A0D2ENV1 View 3D Structure Click here
A0A0D2F2D8 View 3D Structure Click here
A0A0D2G2P5 View 3D Structure Click here
A0A0D2G8I5 View 3D Structure Click here
A0A0D2GDI6 View 3D Structure Click here
A0A0D2GJF5 View 3D Structure Click here
A0A0D2GR15 View 3D Structure Click here
A0A0D2GWV7 View 3D Structure Click here