RND efflux pump, membrane fusion protein (IPR006143)

Short name: RND_pump_MFP

Overlapping homologous superfamilies


Family relationships


This entry represents a large family of polypeptides, the MFP (for membrane fusion protein) family. MFPs are a component of the RND family of transporters (RND refers to resistance, nodulation, and cell division). MFPs are proposed to span the periplasm in some way linking the inner and outer membranes [PMID: 1495479]. However, some members of this family are found in Gram-positive bacteria, where there is no outer membrane. MFPs are involved in the export of a variety of compounds, from drug molecules to large polypeptides, and are united by their similar overall structural organisation, combined with some conserved regions [PMID: 16237030].

This family includes:

  • Haemolysin secretion protein D (HlyD) from Escherichia coli.
  • Lactococcin A secretion protein LcnD from Lactococcus lactis [PMID: 1622271].
  • RTX-I toxin determinant D from Actinobacillus pleuropneumoniae.
  • Calmodulin-sensitive adenylate cyclase-haemolysin (cyclolysin) CyaD from Bordetella pertussis.
  • Colicin V secretion protein CvaA from E. coli [PMID: 2249654].
  • Proteases secretion protein PrtE from Erwinia chrysanthemi [PMID: 2184029].
  • Alkaline protease secretion protein AprE from Pseudomonas aeruginosa [PMID: 1427098].
  • Several multidrug resistance proteins [PMID: 15117957].

GO terms

Biological Process

GO:0055085 transmembrane transport

Molecular Function

GO:0022857 transmembrane transporter activity

Cellular Component

GO:0016020 membrane

Contributing signatures

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