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Crystal structure of an asymmetric trimer of a bacterial glutamate transporter homolog.

ABSTRACT: We report a structure of a trimeric glutamate transporter homolog from Pyrococcus horikoshii with two protomers in an inward facing state and the third in an intermediate conformation between the outward and inward facing states. The intermediate shows a cavity in the thinnest region of the transporter, which is potentially accessible to extracellular and cytoplasmic solutions. Our findings suggest a structural principle by which transport intermediates may mediate uncoupled permeation of polar solutes.

SUBMITTER: Verdon G

PROVIDER: S-EPMC3633560 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Crystal structure of an asymmetric trimer of a bacterial glutamate transporter homolog.

Verdon Grégory G Boudker Olga O

Nature structural & molecular biology 20120212 3

We report a structure of a trimeric glutamate transporter homolog from Pyrococcus horikoshii with two protomers in an inward facing state and the third in an intermediate conformation between the outward and inward facing states. The intermediate shows a cavity in the thinnest region of the transporter, which is potentially accessible to extracellular and cytoplasmic solutions. Our findings suggest a structural principle by which transport intermediates may mediate uncoupled permeation of polar ...[more]

PMID: 22343718

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