Ferric enterobactin receptor protein A (FepA)

Ferric enterobactin receptor protein A (FepA) is a TonB-dependent outer membrane receptor found in Gram-negative bacteria such as Escherichia coli and Pseudomonas aeruginosa[1][5][6]. It binds and actively imports ferric-enterobactin—a siderophore-iron complex—across the outer membrane into the periplasm, a process powered indirectly via the inner membrane TonB–ExbB–ExbD complex[1][7]. Structurally, FepA is a 22-stranded β-barrel porin with a globular N-terminal plug domain that blocks the barrel and undergoes conformational changes to permit substrate transport[1][7]. FepA also serves as a receptor for certain bacteriocins such as colicin B and D, and is essential for high-affinity iron acquisition that supports bacterial growth and virulence under iron-restricted conditions[1][3][5]. Because iron uptake is crucial for pathogenic bacteria, FepA and homologs are explored as potential antibacterial targets and vaccine antigens, and antibodies against FepA have been shown to inhibit bacterial growth in some experimental settings[4][6].

Other names

Ferric enterobactin receptorFepAEnterobactin receptorSiderophore receptor FepA

Blockade or competition for ferric enterobactin binding (e.g., antibodies, modified siderophores); Disruption of iron uptake via inhibition of TonB-dependent transport; Cytotoxic protein delivery via receptor (colicins)