Figure 6: Pseudo symmetries of rhodopsin-arrestin crystal packing.
From: X-ray laser diffraction for structure determination of the rhodopsin-arrestin complex
(a) Pseudo-translational symmetry of the four T4L-rhodopsin-arrestin complex molecules is shown in the asymmetric unit with two of the four molecules translated by approximately half of the unit cell along the unit cell a and b axes. The unit cell is shown as a square box. (b) Pseudo-rotational symmetry of T4L-rhodopsin-arrestin complex molecules is shown in the asymmetric unit, where two of the four molecules can be overlaid by a 180° rotation around the a/b axis. Crystals with pseudo rotational symmetry are prone to twinning and the data is consistent with pseudomerohedral twinning of P212121.
