Periplasmic binding protein (IPR025997)

Short name: SBP_2_dom

Overlapping homologous superfamilies

Domain relationships



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].

On the basis of sequence similarities, the vast majority of these solute-binding proteins can be grouped into eight family clusters [PMID: 8336670], which generally correlate with the nature of the solute bound. This entry represents the family 2 [PMID: 8336670, PMID: 6340108].

Family 2 members include:

  • Autoinducer 2-binding protein LsrB from E. coli and Salmonella typhimurium [PMID: 15601708, PMID: 11722742]
  • D-galactose-binding periplasmic protein
  • Autoinducer 2-binding periplasmic protein LuxP
  • D-ribose-binding periplasmic protein
  • Multiple sugar-binding periplasmic receptor ChvE

This entry represents a domain found in a variety of bacterial periplasmic binding proteins belonging mainly to family 2.

Contributing signatures

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