2NWW

Crystal structure of GltPh in complex with TBOA

Summary for 2NWW

• Entry DOI: 10.2210/pdb2nww/pdb
• Related: 1xhf
• Descriptor: 425aa long hypothetical proton glutamate symport protein, (3S)-3-(BENZYLOXY)-L-ASPARTIC ACID (3 entities in total)
• Functional Keywords: amino acid transporter, transmembrane transporter, aspartate transporter, binding site, inhibitor binding binding, transport protein
• Biological source: Pyrococcus horikoshii
• Total number of polymer chains: 3
• Total formula weight: 134643.51

Authors

Gouaux, E.,Boudker, O.,Ryan, R.,Yernool, D.,Shimamoto, K. (deposition date: 2006-11-16, release date: 2007-02-27, Last modification date: 2023-08-30)

Primary citation

Boudker, O.,Ryan, R.M.,Yernool, D.,Shimamoto, K.,Gouaux, E.
Coupling substrate and ion binding to extracellular gate of a sodium-dependent aspartate transporter.
Nature, 445:387-393, 2007

PubMed Abstract: Secondary transporters are integral membrane proteins that catalyse the movement of substrate molecules across the lipid bilayer by coupling substrate transport to one or more ion gradients, thereby providing a mechanism for the concentrative uptake of substrates. Here we describe crystallographic and thermodynamic studies of Glt(Ph), a sodium (Na+)-coupled aspartate transporter, defining sites for aspartate, two sodium ions and d,l-threo-beta-benzyloxyaspartate, an inhibitor. We further show that helical hairpin 2 is the extracellular gate that controls access of substrate and ions to the internal binding sites. At least two sodium ions bind in close proximity to the substrate and these sodium-binding sites, together with the sodium-binding sites in another sodium-coupled transporter, LeuT, define an unwound alpha-helix as the central element of the ion-binding motif, a motif well suited to the binding of sodium and to participation in conformational changes that accompany ion binding and unbinding during the transport cycle.

PubMed: 17230192
DOI: 10.1038/nature05455

Experimental method

X-RAY DIFFRACTION (3.2 Å)