Outer membrane protein OmpA-like, transmembrane domain (IPR000498)

Short name: OmpA-like_TM_dom

Overlapping homologous superfamilies

Domain relationships



The ompA-like transmembrane domain is present in a number of different outer membrane proteins of several Gram-negative bacteria. Many of the proteins having this domain in the N-terminal also have the conserved bacterial outer membrane protein domain IPR006664 at the C terminus. The outer membrane protein A of Escherichia coli (OmpA), is one of the most studied proteins in this group [PMID: 10554771]. It has a multifunctional role. OmpA is required for the action of colicins K and L and for the stabilisation of mating aggregates in conjugation. It also serves as a receptor for a number of T-even like phages and can act as a porin with low permeability that allows slow penetration of small solutes [PMID: 1974149].

OmpA consists of a regular, extended eight-stranded beta-barrel and appears to be constructed like an inverse micelle with large water-filled cavities, but does not form a pore. The cavities seem to be highly conserved during evolution. The structure corroborates the concept that all outer membrane proteins consist of beta-barrels [PMID: 9808047]. The beta-barrel membrane anchor appears to be the outer membrane equivalent of the single-chain alpha-helix anchor of the inner membrane.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0009279 cell outer membrane
GO:0016021 integral component of membrane

Contributing signatures

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