PMID: 29476011 , Related PDB ids: 4d64, 5nxr, 5nxu, 4d65, 5n9i, 5n9h, 5nxn

Authors:

El-Khatib M, Nasrallah C, Lopes J, Tran QT, Tetreau G, Basbous H, Fenel D, Gallet B, Lethier M, Bolla JM, Pages JM, Vivaudou M, Weik M, Winterhalter M, Colletier JP

Title:

Porin self-association enables cell-to-cell contact in Providencia stuartii floating communities.

Journal:

Proc Natl Acad Sci U S A. 2018 Mar 6;115(10):E2220-E2228. doi:, 10.1073/pnas.1714582115. Epub 2018 Feb 23.

Abstract:

The gram-negative pathogen Providencia stuartii forms floating communities within which adjacent cells are in apparent contact, before depositing as canonical surface-attached biofilms. Because porins are the most abundant proteins in the outer membrane of gram-negative bacteria, we hypothesized that they could be involved in cell-to-cell contact and undertook a structure-function relationship study on the two porins of P. stuartii, Omp-Pst1 and Omp-Pst2. Our crystal structures reveal that these porins can self-associate through their extracellular loops, forming dimers of trimers (DOTs) that could enable cell-to-cell contact within floating communities. Support for this hypothesis was obtained by studying the porin-dependent aggregation of liposomes and model cells. The observation that facing channels are open in the two porin structures suggests that DOTs could not only promote cell-to-cell contact but also contribute to intercellular communication.