GspD/PilQ family (IPR001775)

Short name: GspD/PilQ

Overlapping homologous superfamilies


Family relationships


The general (type II) secretion pathway (Gsp) within Gram-negative bacteria is a signal sequence-dependent process responsible for protein export [PMID: 8438237, PMID: 1365398, PMID: 1592799]. The process has two stages: exoproteins are first translocated across the inner membrane by the general signal-dependent export pathway (GEP), and then across the outer membrane by a species-specific accessory mechanism.

A number of proteins are involved in the Gsp; one of these is known as protein D (GspD protein), the most probable location of which is the outer membrane [PMID: 2677007]. This suggests that protein D constitutes the apparatus of the accessory mechanism, and is thus involved in transporting exoproteins from the periplasm, across the outer membrane, to the extracellular environment.

This entry represents GspD and close homologues, including the type IV pilus outer membrane secretin PilQ.

Contributing signatures

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