Convergent evolution of distinct D-ribulose utilisation pathways in attaching and effacing pathogens.

ABSTRACT: Attaching and effacing pathogens overcome colonisation resistance by competing with metabolically similar organisms for limited resources. Enterohaemorrhagic E. coli (EHEC) utilises the pathogenicity island-encoded Accessory ʟ-arabinose Uptake (Aau) transporter to effectively colonise the mouse gut, hypothesised to be achieved via an enhanced capacity to scavenge ʟ-arabinose. Aau is regulated exclusively in response to ʟ-arabinose, but it is unclear how this system specifically benefits EHEC in vivo. Here, we show that Aau displays a > 200-fold higher affinity for the monosaccharide D-ribulose, over ʟ-arabinose. EHEC cannot grow on D-ribulose as a sole carbon source and this sugar does not trigger aau transcription. However, Aau effectively transports D-ribulose into the cell only in the p

SUBMITTER: Cottam C 

PROVIDER: S-EPMC12307932 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature