Coupled binding mechanism of three sodium ions and aspartate in the glutamate transporter homologue GltTk.
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 GltTkin 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.
University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Albert
0000-0003-2340-2216
A
Guskov
University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Sonja
S
Jensen
University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Ignacio
I
Faustino
University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, Nijenborgh 4, 9747 AG Groningen, The Netherlands.|University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Siewert J
SJ
Marrink
University of Groningen, Groningen Biomolecular Sciences and Biotechnology Institute, Nijenborgh 4, 9747 AG Groningen, The Netherlands.|University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Dirk Jan
DJ
Slotboom
D000595:Amino Acid Sequence; D027322:Amino Acid Transport System X-AG / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019843:Archaeal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001224:Aspartic Acid / Q000737:chemistry / Q000378:metabolism*; D001665:Binding Sites / Q000235:genetics; D018360:Crystallography, X-Ray; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D011485:Protein Binding; D000072417:Protein Domains; D017386:Sequence Homology, Amino Acid; D012964:Sodium / Q000737:chemistry / Q000378:metabolism*; D019712:Thermococcus / Q000235:genetics / Q000378:metabolism; D013816:Thermodynamics
D027322:Amino Acid Transport System X-AG; D019843:Archaeal Proteins; D001224:Aspartic Acid; D012964:Sodium