Frontiers in cellular and infection microbiology
The arginine repressor ArgR controls virulence factors of adherent-invasive Escherichia coli strains
By Bonet-Rossinyol Q, Martinez-Medina M and Fernández-Coll L.
Abstract
Introduction
Adherent-invasive Escherichia coli (AIEC) has been related to the physiopathology of Crohn's disease, yet its pathogenic mechanisms are not completely understood. Arginine biosynthesis genes are upregulated in AIEC strains compared to non-AIEC strains present in the supernatant of infected intestinal epithelial cells, suggesting that arginine biosynthesis may be involved in AIEC pathogenicity.
Methods
To test this hypothesis, the argR gene, encoding the transcriptional repressor ArgR, was deleted in the AIEC strains AIEC16 and LF82, and in E. coli Nissle 1917 and K-12 C600, leading to increased expression of arginine biosynthesis genes. Phenotypic assays and transcriptomic analyses were conducted to assess differences between mutants (ΔargR) and wild-type (WT) strains.