title: Glutamate transporters combine transporter- and channel-like features.
abstract: Glutamate transporters in the mammalian central nervous system have a unique position among secondary transport proteins as they exhibit glutamate-gated chloride-channel activity in addition to glutamate-transport activity. In this article, the available data on the structure of the glutamate transporters are compared with high-resolution crystal structures of channel proteins. In addition, binding-site properties of glutamate transporters, and the ligand-binding site of an ionotropic glutamate receptor of which the crystal structure is known, are compared. Possible structural solutions for the combination of channel and transporter activity in one membrane protein are proposed.
authors.affiliation: Dept of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9751 NN Haren, The Netherlands.
authors.forename: D J
authors.initials: DJ
authors.lastname: Slotboom
authors.forename: W N
authors.initials: WN
authors.lastname: Konings
authors.forename: J S
authors.initials: JS
authors.lastname: Lolkema
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000737:chemistry* / Q000378:metabolism*; D027322:Amino Acid Transport System X-AG; D001426:Bacterial Proteins; D001665:Binding Sites; D002412:Cations; D018118:Chloride Channels / Q000737:chemistry; D007473:Ion Channels / Q000737:chemistry; D015221:Potassium Channels / Q000737:chemistry
chemical_list: D018528:ATP-Binding Cassette Transporters; D027322:Amino Acid Transport System X-AG; D001426:Bacterial Proteins; D002412:Cations; D018118:Chloride Channels; D007473:Ion Channels; D015221:Potassium Channels; C107790:prokaryotic potassium channel