FIGURE 3. Fold of a GltPhH7 protomer.
From the following article:
Structure of a glutamate transporter homologue from Pyrococcus horikoshii
Dinesh Yernool, Olga Boudker, Yan Jin and Eric Gouaux
Nature 431, 811-818(14 October 2004)
doi:10.1038/nature03018
a, Ribbon representation of the protomer viewed in the plane of the membrane in which the transmembrane helices (1–8) and hairpins (HP1, HP2) are labelled and in different colours. The 
-carbon atoms of Ser 279 (HP1) and Gly 354 (HP2) are defined by yellow spheres, which are equivalent to Ala 364 and Ser 440 of GLT-1 (ref. 29). b, View of the protomer from the cytoplasm. c, Schematic representation of the protomer fold. d, Slice of electron density from a 2Fo - Fc map, contoured at 1
, overlaying a stick model of a protomer.