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Coupled binding mechanism of three sodium ions and aspartate in the glutamate transporter homologue GltTk.

ABSTRACT: Glutamate transporters catalyse the thermodynamically unfavourable transport of anionic amino acids across the cell membrane by coupling it to the downhill transport of cations. This coupling mechanism is still poorly understood, in part because the available crystal structures of these transporters are of relatively low resolution. Here we solve crystal structures of the archaeal transporter GltTk in the presence and absence of aspartate and use molecular dynamics simulations and binding assays to show how strict coupling between the binding of three sodium ions and aspartate takes place.

SUBMITTER: Guskov A

PROVIDER: S-EPMC5110648 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Coupled binding mechanism of three sodium ions and aspartate in the glutamate transporter homologue Glt<sub>Tk</sub>.

Guskov Albert A Jensen Sonja S Faustino Ignacio I Marrink Siewert J SJ Slotboom Dirk Jan DJ

Nature communications 20161110

Glutamate transporters catalyse the thermodynamically unfavourable transport of anionic amino acids across the cell membrane by coupling it to the downhill transport of cations. This coupling mechanism is still poorly understood, in part because the available crystal structures of these transporters are of relatively low resolution. Here we solve crystal structures of the archaeal transporter Glt<sub>Tk</sub> in the presence and absence of aspartate and use molecular dynamics simulations and bin ...[more]

PMID: 27830699

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