Structure of TonB in complex with FhuA, E. coli outer membrane receptor.
The cytoplasmic membrane protein TonB spans the periplasm of the Gram-negative bacterial cell envelope, contacts cognate outer membrane receptors, and facilitates siderophore transport. The outer membrane receptor FhuA from Escherichia coli mediates TonB-dependent import of ferrichrome. We report the 3.3 angstrom resolution crystal structure of the TonB carboxyl-terminal domain in complex with FhuA. TonB contacts stabilize FhuA's amino-terminal residues, including those of the consensus Ton box sequence that form an interprotein beta sheet with TonB through strand exchange. The highly conserved TonB residue arginine-166 is oriented to form multiple contacts with the FhuA cork, the globular domain enclosed by the beta barrel.
Pawelek
Peter D
PD
Department of Microbiology and Immunology, McGill University, 3775 University Street, Montreal, Quebec, H3A 2B4, Canada.
Croteau
Nathalie
N
Ng-Thow-Hing
Christopher
C
Khursigara
Cezar M
CM
Moiseeva
Natalia
N
Allaire
Marc
M
Coulton
James W
JW
D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000378:metabolism; D005290:Ferric Compounds / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D020349:Surface Plasmon Resonance
D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; D005290:Ferric Compounds; C050900:FhuA protein, E coli; D008565:Membrane Proteins; C489181:tonB protein, E coli