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15  structures 261  species 0  interactions 688  sequences 11  architectures

Family: Arabinose_trans (PF04602)

Summary: Mycobacterial cell wall arabinan synthesis protein

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This is the Wikipedia entry entitled "Arabinosyltransferase". More...

Arabinosyltransferase Edit Wikipedia article

Symbol Arabinose_trans
Pfam PF04602
Pfam clan CL0111
InterPro IPR007680

An arabinosyltransferase is a transferase enzyme acting upon arabinose.[1] This enzyme is involved in polymerisation of arabinogalactan (an essential component of the mycobacterial cell wall). Mycobacterially, the more precise term is arabinofuranosyltransferase, since the arabinose residues occur only in a furanose form.

This enzyme has important clinical applications as it is believed to be the target of the antimycobacterial drug Ethambutol.[2]


  1. ^ Zhang J, Angala SK, Pramanik PK, Li K, Crick DC, Liav A, Jozwiak A, Swiezewska E, Jackson M, Chatterjee D (2011). "Reconstitution of functional mycobacterial arabinosyltransferase AftC proteoliposome and assessment of decaprenylphosphorylarabinose analogues as arabinofuranosyl donors". ACS Chem. Biol. 6: 819–28. doi:10.1021/cb200091m. PMC 3158817Freely accessible. PMID 21595486. 
  2. ^ Belanger AE, Besra GS, Ford ME, Mikusova K, Belisle JT, Brennan PJ, Inamine JM (October 1996). "The embAB genes of Mycobacterium avium encode an arabinosyl transferase involved in cell wall arabinan biosynthesis that is the target for the antimycobacterial drug ethambutol". Proc. Natl. Acad. Sci. U.S.A. 93 (21): 11919–24. doi:10.1073/pnas.93.21.11919. PMC 38159Freely accessible. PMID 8876238. 

This article incorporates text from the public domain Pfam and InterPro IPR007680

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.

Mycobacterial cell wall arabinan synthesis protein Provide feedback

Arabinosyltransferase is involved in arabinogalactan (AG) biosynthesis pathway in mycobacteria. AG is a component of the macromolecular assembly of the mycolyl-AG-peptidoglycan complex of the cell wall. This enzyme has important clinical applications as it is believed to be the target of the antimycobacterial drug Ethambutol [1].

Literature references

  1. Belanger AE, Besra GS, Ford ME, Mikusova K, Belisle JT, Brennan PJ, Inamine JM; , Proc Natl Acad Sci U S A 1996;93:11919-11924.: The embAB genes of Mycobacterium avium encode an arabinosyl transferase involved in cell wall arabinan biosynthesis that is the target for the antimycobacterial drug ethambutol. PUBMED:8876238 EPMC:8876238

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR007680

Arabinosyltransferases EmbA, EmbB and EmbC are known to be involved in arabinogalactan (AG) and lipoarabinomannan (LAM) biosynthesis in mycobacteria. Synthesis of LAM, but not AG, ceases after inactivation of EmbC, while the arabinan of AG is affected by EmbA or EmbB disruption [ PUBMED:14507364 ]. The arabinans of the mycobacterial cell wall are key structural and immunological polymers. These enzymes could have important clinical applications as they are believed to be the target of the antimycobacterial drug Ethambutol [ PUBMED:8876238 ].

This entry represents the central domain found in arabinosyltransferase EmbA, EmbB and EmbC.

Gene Ontology

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Domain organisation

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Pfam Clan

This family is a member of clan GT-C (CL0111), which has the following description:

This is the GT-C clan that contains diverse glycosyltransferases that possess 8-13 predicted transmembrane segments [1].

The clan contains the following 19 members:

ALG3 Alg6_Alg8 Arabinose_trans DIE2_ALG10 DUF2079 DUF2142 DUF2723 EpsG Glucan_synthase Glyco_transf_22 GT87 Mannosyl_trans Mannosyl_trans2 PIG-U PMT PMT_2 PTPS_related STT3 YfhO


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Curation and family details

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Seed source: Pfam-B_4670 (release 7.5)
Previous IDs: arab_transf;
Type: Family
Sequence Ontology: SO:0100021
Author: Waterfield DI , Finn RD
Number in seed: 23
Number in full: 688
Average length of the domain: 449.50 aa
Average identity of full alignment: 44 %
Average coverage of the sequence by the domain: 43.01 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 25.0 25.0
Trusted cut-off 31.5 30.4
Noise cut-off 23.1 21.9
Model length: 459
Family (HMM) version: 14
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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


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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 Arabinose_trans domain has been found. There are 15 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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