ABC transporter, phosphonate import, PhnC (IPR012693)

Short name: ABC_transpr_PhnC

Overlapping homologous superfamilies

Family relationships



The ATP-Binding Cassette (ABC) superfamily forms one of the largest of all protein families with a diversity of physiological functions [PMID: 9873074]. Several studies have shown that there is a correlation between the functional characterisation and the phylogenetic classification of the ABC cassette [PMID: 9873074, PMID: 11421270]. More than 50 subfamilies have been described based on a phylogenetic and functional classification [PMID: 9873074, PMID: 11421269, PMID: 11421270].

Members of this protein family are the ABC transporters of phosphonates. Phosphonates are a class of phosphorus-containing organic compound with a stable direct C-P bond rather than a C-O-P linkage. Phosphonates are widespread among naturally occurring compounds in all kingdoms of wildlife, but only prokaryotic microorganisms are able to cleave this bond. Certain bacteria such as E. coli can use alkylphosphonates as a phosphorus source. A number of bacterial species have operons, typically about 14 genes in size, with genes for ATP-dependent transport of phosphonates, degradation, and regulation of the expression of the system [PMID: 1368181, PMID: 11952414, PMID: 8755882, PMID: 8335257, PMID: 1846145].

This entry also includes transporters of phosphite (an organophosphorous compound with the formula P(OR)3) and hypophosphite (H2PO-2), including the phosphite import ATP-binding protein PxtA and hypophosphite import ATP-binding protein HtxD, both from Pseudomonas stutzeri [PMID: 9791102].

GO terms

Biological Process

GO:0015716 organic phosphonate transport

Molecular Function

GO:0005524 ATP binding
GO:0015416 ATPase-coupled organic phosphonate transmembrane transporter activity

Cellular Component

GO:0016020 membrane

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE profiles