Phosphate ABC transporter, substrate-binding protein PstS (IPR005673)

Short name: ABC_phos-bd_PstS

Overlapping homologous superfamilies


Family relationships



PstS is the substrate-binding component of the ABC-type transporter complex pstSACB, involved in phosphate import. This protein is accompanied, generally in the same operon, by an ATP binding protein (pstB) and two permease proteins (pstC and pstA). The accumulation of this protein is enhanced under phosphate starvation [PMID: 18820899, PMID: 9139906].

Bacterial high affinity transport systems are involved in active transport of solutes across the cytoplasmic membrane. Most of the bacterial ABC (ATP-binding cassette) importers are composed of one or two transmembrane permease proteins, one or two nucleotide-binding proteins and a highly specific periplasmic solute-binding protein. In Gram-negative bacteria the solute-binding proteins are dissolved in the periplasm, while in archaea and Gram-positive bacteria, their solute-binding proteins are membrane-anchored lipoproteins [PMID: 8003968, PMID: 18310026].

GO terms

Biological Process

GO:0035435 phosphate ion transmembrane transport

Molecular Function

GO:0042301 phosphate ion binding

Cellular Component

GO:0043190 ATP-binding cassette (ABC) transporter complex

Contributing signatures

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