1. Molecular determinant of ion selectivity of a (Na+ + K+)-coupled rat brain?glutamate?transporter - Zhang, Yumin; Bendahan, Annie; Zarbiv, Ruth; Kavanaugh, Michael P.; Kanner, Baruch I.
Glutamate transporters remove this neurotransmitter from the synaptic cleft by a two-stage electrogenic process, in which glutamate is first cotransported with three sodium ions and a proton. Subsequently, the cycle is completed by translocation of a potassium ion in the opposite direction. Recently, we have identified an amino acid residue of the glutamate transporter GLT-1 (Glu-404) that influences potassium coupling. We have now analyzed the effect of seven other amino acid residues in the highly conserved region surrounding this site. One of these residues, Tyr-403, also proved important for potassium coupling, because mutation to Phe (Y403F) resulted in an electroneutral...
- 05-dic-2006