TonB induces conformational changes in surface-exposed loops of FhuA, outer membrane receptor of Escherichia coli.

ABSTRACT: FhuA, outer membrane receptor of Escherichia coli, transports hydroxamate-type siderophores into the periplasm. Cytoplasmic membrane-anchored TonB transduces energy to FhuA to facilitate siderophore transport. Because the N-terminal cork domain of FhuA occludes the C-terminal beta-barrel lumen, conformational changes must occur to enable siderophore passage. To localize conformational changes at an early stage of the siderophore transport cycle, four anti-FhuA monoclonal antibodies (mAbs) were purified to homogeneity, and the epitopes that they recognize were determined by phage display. We mapped continuous and discontinuous epitopes to outer surface-exposed loops 3, 4, and 5 and to beta-barrel strand 14. To probe for conformational changes of FhuA, surface plasmon resonance measured mAb

SUBMITTER: James KJ 

PROVIDER: S-EPMC2548371 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature