Position of the third Na+ site in the aspartate transporter GltPh and the human glutamate transporter, EAAT1.

ABSTRACT: Glutamate transport via the human excitatory amino acid transporters is coupled to the co-transport of three Na(+) ions, one H(+) and the counter-transport of one K(+) ion. Transport by an archaeal homologue of the human glutamate transporters, Glt(Ph), whose three dimensional structure is known is also coupled to three Na(+) ions but only two Na(+) ion binding sites have been observed in the crystal structure of Glt(Ph). In order to fully utilize the Glt(Ph) structure in functional studies of the human glutamate transporters, it is essential to understand the transport mechanism of Glt(Ph) and accurately determine the number and location of Na(+) ions coupled to transport. Several sites have been proposed for the binding of a third Na(+) ion from electrostatic calculations and molecular d

SUBMITTER: Bastug T 

PROVIDER: S-EPMC3302783 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature