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5  structures 5747  species 0  interactions 181668  sequences 489  architectures

Family: MFS_1 (PF07690)

Summary: Major Facilitator Superfamily

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Major facilitator family Edit Wikipedia article

Major facilitator superfamily
PDB 1pw4 EBI.jpg
Structure of the glycerol-3-phosphate transporter from Escherichia coli.[1]
Symbol MFS_1
Pfam PF07690
InterPro IPR011701
SCOP 1pw4
TCDB 2.A.1
OPM superfamily 15
OPM protein 1pw4
CDD cd06174

The major facilitator superfamily (MFS) is a class of membrane transport proteins that facilitate movement of small solutes across cell membranes in response to chemiosmotic ion gradients.[2][3]


Genome-sequencing data have revealed the occurrence of dozens of families of primary and secondary transporters. Two such families have been found to occur ubiquitously in all classifications of living organisms. These are the ATP-binding cassette (ABC) superfamily and the major facilitator superfamily (MFS), also called the uniporter-symporter-antiporter family. While ABC family permeases are in general multicomponent primary active transporters, capable of transporting both small molecules and macromolecules in response to ATP hydrolysis the MFS transporters are single-polypeptide secondary carriers capable only of transporting small solutes in response to chemiosmotic ion gradients. Although well over 100 families of transporters have now been recognised and classified, the ABC superfamily and MFS account for nearly half of the solute transporters encoded within the genomes of microorganisms. They are also prevalent in higher organisms.[4]


The MFS was originally believed to function primarily in the uptake of sugars but subsequent studies revealed that drug efflux systems, Krebs cycle metabolites, organophosphate:phosphate exchangers, oligosaccharide:H1 symport permeases, and bacterial aromatic acid permeases were all members of the MFS. These observations led to the probability that the MFS is far more widespread in nature and far more diverse in function than had been thought previously. 17 subgroups of the MFS have been identified.[4]


Evidence suggests that the MFS permeases arose by a tandem intragenic duplication event in the early prokaryotes. This event generated a 2-transmembrane-spanner (TMS) protein topology from a primordial 6-TMS unit. All currently recognised MFS permeases retain the two six-TMS units within a single polypeptide chain, although in 3 of the 17 MFS families, an additional two TMSs are found.[5] Moreover, the well-conserved MFS specific motif between TMS2 and TMS3 and the related but less well conserved motif between TMS8 and TMS9[6] prove to be a characteristic of virtually all of the more than 300 MFS proteins identified.


Human proteins containing this domain include:


  1. ^ Huang Y, Lemieux MJ, Song J, Auer M, Wang DN (August 2003). "Structure and mechanism of the glycerol-3-phosphate transporter from Escherichia coli". Science 301 (5633): 616–20. doi:10.1126/science.1087619. PMID 12893936. 
  2. ^ Paulsen IT, Pao SS, Saier Jr MH (1998). "Major Facilitator Superfamily". Microbiol. Mol. Biol. Rev. 62 (1): 1–34. PMC 98904. PMID 9529885. 
  3. ^ Walmsley AR, Barrett MP, Bringaud F, Gould GW (December 1998). "Sugar transporters from bacteria, parasites and mammals: structure-activity relationships". Trends Biochem. Sci. 23 (12): 476–81. doi:10.1016/S0968-0004(98)01326-7. PMID 9868370. 
  4. ^ a b Pao SS, Paulsen IT, Saier MH (March 1998). "Major facilitator superfamily". Microbiol. Mol. Biol. Rev. 62 (1): 1–34. PMC 98904. PMID 9529885. 
  5. ^ Paulsen IT, Brown MH, Skurray RA (December 1996). "Proton-dependent multidrug efflux systems". Microbiol. Rev. 60 (4): 575–608. PMC 239457. PMID 8987357. 
  6. ^ Henderson PJ, Maiden MC (January 1990). "Homologous sugar transport proteins in Escherichia coli and their relatives in both prokaryotes and eukaryotes". Philos. Trans. R. Soc. Lond., B, Biol. Sci. 326 (1236): 391–410. PMID 1970645. 

This article incorporates text from the public domain Pfam and InterPro IPR011701

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

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This tab holds annotation information from the InterPro database.

InterPro entry IPR011701

Among the different families of transporter, only two occur ubiquitously in all classifications of organisms. These are the ATP-Binding Cassette (ABC) superfamily and the Major Facilitator Superfamily (MFS). The MFS transporters are single-polypeptide secondary carriers capable only of transporting small solutes in response to chemiosmotic ion gradients [PUBMED:9529885, PUBMED:9868370].

Gene Ontology

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Domain organisation

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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 using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...

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

External links

MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.

Pfam alignments:

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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.

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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.

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Seed source: Pfam-B_5 (Release 13.0)
Previous IDs: none
Type: Family
Author: Bateman A
Number in seed: 195
Number in full: 181668
Average length of the domain: 295.20 aa
Average identity of full alignment: 13 %
Average coverage of the sequence by the domain: 82.52 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 32.6 32.6
Trusted cut-off 32.6 32.6
Noise cut-off 32.5 32.5
Model length: 352
Family (HMM) version: 11
Download: download the raw HMM for this family

Species distribution

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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 MFS_1 domain has been found. There are 5 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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