6XWQ

Structure of glutamate transporter homologue GltTk in the saturated conditions

Summary for 6XWQ

• Entry DOI: 10.2210/pdb6xwq/pdb
• Related: 6XWN 6XWO 6XWP 6XWR
• EMDB information: 10635
• Descriptor: Proton/glutamate symporter, SDF family, ASPARTIC ACID (2 entities in total)
• Functional Keywords: amino acid transporter, aspartate transport, glutamate transporter homologue, transport protein, membrane protein
• Biological source: Thermococcus kodakarensis (strain ATCC BAA-918 / JCM 12380 / KOD1)
• Total number of polymer chains: 3
• Total formula weight: 137139.92

Authors

Arkhipova, V.,Slotboom, D.J.,Guskov, A. (deposition date: 2020-01-24, release date: 2020-03-04, Last modification date: 2025-07-02)

Primary citation

Arkhipova, V.,Guskov, A.,Slotboom, D.J.
Structural ensemble of a glutamate transporter homologue in lipid nanodisc environment.
Nat Commun, 11:998-998, 2020

PubMed Abstract: Glutamate transporters are cation-coupled secondary active membrane transporters that clear the neurotransmitter L-glutamate from the synaptic cleft. These transporters are homotrimers, with each protomer functioning independently by an elevator-type mechanism, in which a mobile transport domain alternates between inward- and outward-oriented states. Using single-particle cryo-EM we have determined five structures of the glutamate transporter homologue Glt, a Na- L-aspartate symporter, embedded in lipid nanodiscs. Dependent on the substrate concentrations used, the protomers of the trimer adopt a variety of asymmetrical conformations, consistent with the independent movement. Six of the 15 resolved protomers are in a hitherto elusive state of the transport cycle in which the inward-facing transporters are loaded with Na ions. These structures explain how substrate-leakage is prevented - a strict requirement for coupled transport. The belt protein of the lipid nanodiscs bends around the inward oriented protomers, suggesting that membrane deformations occur during transport.

PubMed: 32081874
DOI: 10.1038/s41467-020-14834-8

Experimental method

ELECTRON MICROSCOPY (3.41 Å)