title: Hydrodynamic properties of the purified glutamate-binding protein subunit of the N-methyl-D-aspartate receptor.
abstract: The hydrodynamic properties of the previously purified glutamate-binding protein from rat synaptic membranes were determined in order to estimate the molecular size of the protein in its native state. This protein is apparently a subunit of a multisubunit complex that forms the N-methyl-D-aspartate subtype of glutamate receptor and has a molecular size of approximately 70 kDa based on electrophoretic migration under denaturing conditions. On the basis of results obtained from H2O/D2O sucrose density gradient sedimentation and gel filtration chromatography of the purified glutamate-binding protein we calculated the partial specific volume of the protein-detergent complex to be 0.766 cc3/g, the Stokes radius of the complex as 4.9 nm, the Mc of the complex as 203,000 +/- 22,000 and the Mr of the protein as 182,000 +/- 19,000. These results are indicative of stable self-association of the glutamate-binding protein and are in agreement with recent studies indicating that more than one molecule of glutamate may be required to activate the N-methyl-D-aspartate receptor-associated ion channel.
authors.affiliation: Department of Pharmacology and Toxicology, University of Kansas, Lawrence 66045-2505.
authors.forename: K N
authors.initials: KN
authors.lastname: Kumar
authors.forename: K T
authors.initials: KT
authors.lastname: Eggeman
authors.forename: J L
authors.initials: JL
authors.lastname: Adams
authors.forename: E K
authors.initials: EK
authors.lastname: Michaelis
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D051381:Rats; D017470:Receptors, Glutamate; D016194:Receptors, N-Methyl-D-Aspartate / Q000737:chemistry*; D017981:Receptors, Neurotransmitter / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D017470:Receptors, Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter