Fig. 1.

Solution NMR-based conformers of the Zn²⁺ complexed with residues 1–16 (the N-terminal region) fit well with the experiment-based structure for the remainder of the Aβ (residues 17–42), and consequently can be linked to create models of the full-length Aβ₄₂ complexed with Zn²⁺. Zn²⁺-coordinated N-terminal coordinates are taken from refs.  18, 22, and 23. Coordinates of residues 17–42 are taken from ref. 29. Models M1–M3 are with the Zirah coordinates (18) linked to the Lührs coordinates (29). In M1 and M2, the Aβ monomers are arranged in parallel; in M1 with eight Zn²⁺ ions; in M2 with four Zn²⁺ ions; in M3, the monomers are antiparallel with eight Zn²⁺ ions. M6 and M7 are obtained by joining the Gaggelli (22) and Lührs coordinates (29) with eight Zn²⁺ ions, in a parallel organization; M12 is based on the Miniccozzi–Lührs (23, 29) coordinates complexed with eight Zn²⁺ ions in antiparallel organization. The figure presents the two most highly populated conformers of the Zirah–Lührs model: M1 and M3; the two most highly populated conformers of Gaggeli–Lührs model: M6 and M7; and the highly populated conformer based on Miniccozzi–Lührs model.