4P1A
Thallium-bound inward-facing state of the glutamate transporter homologue GltPh
Summary for 4P1A
Entry DOI | 10.2210/pdb4p1a/pdb |
Related | 1XZH 2NWL 2NWW 2NWX 3KBC 3V8F 3V8G 4IZM 4P19 |
Descriptor | GltPh, THALLIUM (I) ION, MERCURY (II) ION (3 entities in total) |
Functional Keywords | membrane protein, sodium-couple, asparate transporter, inward-facing state, thallium binding sites, transport protein |
Biological source | Pyrococcus horikoshii |
Total number of polymer chains | 3 |
Total formula weight | 135675.80 |
Authors | Verdon, G.,Boudker, O. (deposition date: 2014-02-25, release date: 2014-06-04, Last modification date: 2023-12-20) |
Primary citation | Verdon, G.,Oh, S.,Serio, R.N.,Boudker, O. Coupled ion binding and structural transitions along the transport cycle of glutamate transporters. Elife, 3:e02283-e02283, 2014 Cited by PubMed Abstract: Membrane transporters that clear the neurotransmitter glutamate from synapses are driven by symport of sodium ions and counter-transport of a potassium ion. Previous crystal structures of a homologous archaeal sodium and aspartate symporter showed that a dedicated transport domain carries the substrate and ions across the membrane. Here, we report new crystal structures of this homologue in ligand-free and ions-only bound outward- and inward-facing conformations. We show that after ligand release, the apo transport domain adopts a compact and occluded conformation that can traverse the membrane, completing the transport cycle. Sodium binding primes the transport domain to accept its substrate and triggers extracellular gate opening, which prevents inward domain translocation until substrate binding takes place. Furthermore, we describe a new cation-binding site ideally suited to bind a counter-transported ion. We suggest that potassium binding at this site stabilizes the translocation-competent conformation of the unloaded transport domain in mammalian homologues.DOI: http://dx.doi.org/10.7554/eLife.02283.001. PubMed: 24842876DOI: 10.7554/eLife.02283 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (3.75 Å) |
Structure validation
Download full validation report