3KBC

Crystal structure of GltPh K55C-A364C mutant crosslinked with divalent mercury

Summary for 3KBC

• Entry DOI: 10.2210/pdb3kbc/pdb
• Related: 1XFH 2NWL 2NWW 2NWX
• Descriptor: 425aa long hypothetical proton glutamate symport protein, ASPARTIC ACID, MERCURY (II) ION, ... (4 entities in total)
• Functional Keywords: amino acid transporter, transmembrane transporter, aspartate transporter, transport protein, cysteine cross-link, inward-facing
• Biological source: Pyrococcus horikoshii
• Total number of polymer chains: 3
• Total formula weight: 135806.59

Authors

Reyes, N.,Ginter, C.,Boudker, O. (deposition date: 2009-10-20, release date: 2009-12-01, Last modification date: 2023-09-06)

Primary citation

Reyes, N.,Ginter, C.,Boudker, O.
Transport mechanism of a bacterial homologue of glutamate transporters.
Nature, 462:880-885, 2009

PubMed Abstract: Glutamate transporters are integral membrane proteins that catalyse a thermodynamically uphill uptake of the neurotransmitter glutamate from the synaptic cleft into the cytoplasm of glia and neuronal cells by harnessing the energy of pre-existing electrochemical gradients of ions. Crucial to the reaction is the conformational transition of the transporters between outward and inward facing states, in which the substrate binding sites are accessible from the extracellular space and the cytoplasm, respectively. Here we describe the crystal structure of a double cysteine mutant of a glutamate transporter homologue from Pyrococcus horikoshii, Glt(Ph), which is trapped in the inward facing state by cysteine crosslinking. Together with the previously determined crystal structures of Glt(Ph) in the outward facing state, the structure of the crosslinked mutant allows us to propose a molecular mechanism by which Glt(Ph) and, by analogy, mammalian glutamate transporters mediate sodium-coupled substrate uptake.

PubMed: 19924125
DOI: 10.1038/nature08616

Experimental method

X-RAY DIFFRACTION (3.51 Å)