Raunser, S., Appel, M., Ganea, C., Geldmacher-Kaufer, U., Fendler, K., & Kühlbrandt, W. (2006). Structure and function of prokaryotic glutamate transporters from Escherichia coli and Pyrococcus horikoshii. Biochemistry, 45(42), 12796-12805. doi:10.1021/bi061008+.