Figure 3
Packing of two-zipper motifs of class 1–4 zippers. (a) The zipper motif from the GNNQQNY crystal structure (PDB entry 2omm; Sawaya et al., 2007 ) is shown along with a schematic representation of a single peptide by a box (inspired by the presentation in Stroud, 2013 ). The different colours differentiate between C/N-termini, odd/even-residue side chains and the up/down orientation of the given β-sheet. (b) Left column: single zipper motifs of classes 1 to 4 for which all individual sheets are parallel. Middle column: a second zipper motif generated by rotation around a twofold axis parallel to y (perpendicular to the fibril axis). Right column: a second zipper motif generated by rotation around a twofold axis parallel to z (corresponding to the fibril long axis or spine axis). |