Disease relevance of fhuB

• The fhuB, fhuC and fhuD genes encode proteins which catalyze transport of iron(III)-hydroxamate compounds from the periplasm into the cytoplasm of Escherichia coli [1].
• The fhuB, C, D genes were cloned downstream of a strong phage T7 promoter and transcribed by T7 RNA polymerase [1].
• Aerobactin utilization by Neisseria gonorrhoeae and cloning of a genomic DNA fragment that complements Escherichia coli fhuB mutations [2].
• In Rhizobium, fhuB is in an operon fhuDCB, which specifies the cytoplasmic membrane and periplasmic proteins involved in siderophore uptake. fhuDCB mutants make vicibactin when grown in Fe concentrations that inhibit its production in the wild-type [3].

High impact information on fhuB

• However, tris[(acetylhydroxyamino)butyl] isocyanurate 2b, and to some extent its pentyl analogue, 2c, displayed the unique and remarkable property of supporting growth of fhuB mutants, the latter unresponsive to the other analogues and to all natural siderophores tested [4].
• Physical mapping showed that hemL mapped clockwise next to fhuB [5].
• The latter finding supports our previous proposal that fhuB mutants are defective in a function that residues in the cytoplasmic membrane [6].
• Various plasmids carrying only one-half of the fhuB gene were expressed in fhuB- mutants [7].
• Iron hydroxamate transport of Escherichia coli: nucleotide sequence of the fhuB gene and identification of the protein [8].

Anatomical context of fhuB

• Accumulation of [14C]aerobactin in the periplasm of fhuD, fhuB or fhuC mutant strains was not significantly lower than in the wild-type strain, but entry into the cytoplasm was greatly reduced in all cases [9].
• In contrast, transport through the cytoplasmic membrane is catalysed by three common proteins encoded by the fhuB, fhuC and fhuD genes [10].

Associations of fhuB with chemical compounds

• A fhuB mutant (deficient in transport of substrates across the inner membrane) which overproduced the periplasmic FhuD 30-kDa protein, bound [55Fe] iron(III) ferrichrome [11].

References