1fcp
From Proteopedia
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FERRIC HYDROXAMATE UPTAKE RECEPTOR (FHUA) FROM E.COLI IN COMPLEX WITH BOUND FERRICHROME-IRON
Overview
FhuA, the receptor for ferrichrome-iron in Escherichia coli, is a member, of a family of integral outer membrane proteins, which, together with the, energy-transducing protein TonB, mediate the active transport of ferric, siderophores across the outer membrane of Gram-negative bacteria. The, three-dimensional structure of FhuA is presented here in two, conformations: with and without ferrichrome-iron at resolutions of 2.7 and, 2.5 angstroms, respectively. FhuA is a beta barrel composed of 22, antiparallel beta strands. In contrast to the typical trimeric arrangement, found in porins, FhuA is monomeric. Located within the beta barrel is a, structurally distinct domain, the "cork," which mainly consists of a, four-stranded beta sheet and four short alpha helices. A single, lipopolysaccharide molecule is noncovalently associated with the, membrane-embedded region of the protein. Upon binding of ferrichrome-iron, conformational changes are transduced to the periplasmic pocket of FhuA, signaling the ligand-loaded status of the receptor. Sequence homologies, and mutagenesis data are used to propose a structural mechanism for, TonB-dependent siderophore-mediated transport across the outer membrane.
About this Structure
1FCP is a Single protein structure of sequence from Escherichia coli with PO4, NI, LIL, AAE, LIM, EA2 and FCI as ligands. Full crystallographic information is available from OCA.
Reference
Siderophore-mediated iron transport: crystal structure of FhuA with bound lipopolysaccharide., Ferguson AD, Hofmann E, Coulton JW, Diederichs K, Welte W, Science. 1998 Dec 18;282(5397):2215-20. PMID:9856937
Page seeded by OCA on Tue Nov 20 14:49:21 2007
