Ferrichrome outer membrane transporter (FhuA)

The Ferrichrome outer membrane transporter (FhuA) is an integral β-barrel membrane protein in *Escherichia coli* and related Gram-negative bacteria, responsible for importing iron via ferrichrome, a hydroxamate-type siderophore. FhuA specifically binds ferrichrome-iron complexes at the outer membrane and transports them into the periplasm in a process energised by the inner membrane TonB-ExbBD complex. In addition to its physiological role in iron uptake, FhuA serves as a receptor for certain antibiotics (e.g., albomycin), bacteriocins (colicin M, microcin J25), and is a receptor for several phages (T1, T5, phi80, UC-1), making it a bacterial virulence factor and a potential therapeutic target for “Trojan horse” antibiotics and phage therapies[3][4][5][6][9][10].

Other names

Ferric hydroxamate receptorFerric hydroxamate uptakeFerrichrome-iron receptortonAOuter membrane protein receptor for ferrichrome

Drugs (such as albomycin) and bacteriocins utilize FhuA as a gateway to enter the bacterial cell via siderophore-mediated transport, mimicking ferrichrome-iron complex recognition and import[3][4][5].