Figure 9.

Solid-state ¹³C NMR of the Aβ40-I1 complex. A. 2D ¹³C DARR NMR spectrum of the Aβ40 – I1 complex. The spectrum was obtained using Aβ40 labeled with 5-¹³C-Met35 which had been incubated with the I1 inhibitor labeled at Gly2 (1-¹³C) and Gly6 (2-¹³C). Cross peaks (boxed) are observed between the inhibitor (1-¹³C Gly2 and 2-¹³C Gly4 at ~170 ppm and 40 ppm, respectively) and the Aβ40 peptide (5-¹³C Met35 resonance at 15 ppm). B. Structure of the I1 inhibitor bound to a monomer of Aβ40. The two aromatic side chains of the inhibitor (Phe4 and Phe8) pack against Gly33 and Gly37 of the Aβ peptide.