New Role for the ibeA Gene in H2O2 Stress Resistance of Escherichia coli

The IbeA Invasin of Adherent-Invasive Escherichia coli Mediates Interaction with Intestinal Epithelia and Macrophages

“…ns, P Ͼ 0.05; *, P Յ 0.05; **, P Յ 0.01 (compared against the wt strain NRG857c; an unpaired Student t test with Welch's correction, due to differences in the variance between sample populations, was used). play a role in survival to reactive oxygen species (19). Reactive oxygen species are an important part of the macrophage oxidative stress (57,58), and during the first hours after bacterial invasion, where bacteria encounter stress conditions (59), the role of IbeA as a putative FAD-dependent oxidoreductase might be relevant.…”

“…Our results showed that in the absence of IbeA, an impaired intramacrophage survival was observed. The mechanism associated with impaired survival has not been elucidated, but it is plausible to propose that IbeA, which belongs to the Pfam12831 family of FAD-dependent oxidoreductases (19), could (AIEC), NRG857c⌬ibeA (AIEC ⌬ibeA), and MG1655 (nonpathogenic E. coli K-12) or treated with PBS (negative control), and tissue sections of the colon and cecum were obtained at 14 days postinfection. IFN-␥ levels were measured by enzyme-linked immunosorbent assay in the cecum (A) and colon (B).…”

“…No intracellular replication was observed in this experiment compared to previous reports (4). It is worth noting that further insight into the mechanism by which IbeA contributes to AIEC intramacrophage survival needs to be studied, since a report of an APEC strain, BEN2908, suggests that ibeA deletion makes the strain more sensitive to killing by 25 mM H 2 O 2 and implicates IbeA in the resistance to the reactive oxygen species (ROS) response (19). Effect of ibeA deletion on AIEC intestinal colonization of mice.…”

“…Further, IbeA has been associated with early pathogenic events of APEC infections in chickens (18) and with the traversal of the human blood-brain barrier and subsequent access to the bloodstream in NMEC infections (14). The role of IbeA in resistance to oxidative stress has been reported in APEC strain BEN2908; however, its contribution to the pathogenic process is not clear (19). Scarce information exists regarding the molecular mechanisms mediating IbeA interactions with host cells.…”

Virulence factor-dependent basolateral invasion of choroid plexus epithelial cells by pathogenic Escherichia coli in vitro

“…Noteworthy, a contribution of ompA during adhesion to HBMEC has been proposed (Teng et al 2006). Also, for ompA the role in invasion has been demonstrated for various cell lines, including astrocytes and macrophages (Confer and Ayalew 2013;Wu et al 2009), whereas ibeA has been mainly investigated with regards to the brain endothelium (Flechard et al 2012). The K1 capsule phenotype is known to be a prerequisite for meningitis to occur (Kim et al 2003;Kim et al 1992).…”