Assigning a role for chemosensory signal transduction in Campylobacter jejuni biofilms using a combined omics approach

Abstract

Biofilms of the gastroenteric pathogen C. jejuni may serve an important role in the transmission of infection from reservoirs of infection to humans. Herein, we undertook a combinatorial approach examining differential gene expression and protein abundance during biofilm formation in C. jejuni. Biofilms induced a substantial rearrangement of the C. jejuni transcriptome and proteome, with ~600 genes differentially expressed when compared to planktonic cells. Genes and proteins induced in biofilms were involved in iron metabolism and acquisition, cell division, glycan production and attachment, while those repressed were associated with metabolism, amino acid usage, and large tracts of the chemotaxis pathway. We further examined the role of chemotaxis in C. jejuni biofilm formation by examining isogenic strains with deletions of the cheV and cheW signal transduction genes. Both ∆cheV and ∆cheW exhibited a significant decrease in directed motility when compared to wild-type C. jejuni as well as demonstrating an increase in autoagglutination ability and biofilm formation. A subtle difference was also observed between the phenotypes of ∆cheV and ∆cheW mutants, both in motility and biofilm formation. This suggests roles for CheV and CheW and may present signal transduction as a potential method for modulating C. jejuni biofilm formation.