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Structure of the multidrug transporter EmrD from Escherichia coli.

ABSTRACT: EmrD is a multidrug transporter from the Major Facilitator Superfamily that expels amphipathic compounds across the inner membrane of Escherichia coli. Here, we report the x-ray structure of EmrD determined to a resolution of 3.5 angstroms. The structure reveals an interior that is composed mostly of hydrophobic residues, which is consistent with its role transporting amphipathic molecules. Two long loops extend into the inner leaflet side of the cell membrane. This region can serve to recognize and bind substrate directly from the lipid bilayer. We propose that multisubstrate specificity, binding, and transport are facilitated by these loop regions and the internal cavity.

SUBMITTER: Yin Y

PROVIDER: S-EPMC3152482 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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Structure of the multidrug transporter EmrD from Escherichia coli.

Yin Yong Y He Xiao X Szewczyk Paul P Nguyen That T Chang Geoffrey G

Science (New York, N.Y.) 20060501 5774

EmrD is a multidrug transporter from the Major Facilitator Superfamily that expels amphipathic compounds across the inner membrane of Escherichia coli. Here, we report the x-ray structure of EmrD determined to a resolution of 3.5 angstroms. The structure reveals an interior that is composed mostly of hydrophobic residues, which is consistent with its role transporting amphipathic molecules. Two long loops extend into the inner leaflet side of the cell membrane. This region can serve to recognize ...[more]

PMID: 16675700

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