Table 4.

Summary of MAS NMR-based torsion angles in GNNQQNY fibrils. The data include data determined from TALOS chemical shift analysis (Table 2), chemical shift index analysis and Ψ torsion angles determined via NCCN torsion angle measurements

residue	Fibril conformer 1		Fibril conformer 2		Fibril conformer 3
	ϕ	ψ	ϕ	ψ	ϕ	ψ
G7	n/a	166 ±10	n/a	166 ±20	n/a	180 ± 13
N8	−108 ±20	145 ±20	54 ±6a)	40 ±13a)	−119 ±18	131 ±12
N9	−101 ±11	136 ± 18	−88 ±22	150 ±13	−116 ±19	130 ± 12
Q10	−131 ±14	130 ±15	−142 ±13	135 ±15	−146 ±15	121 ±20
Q11	−150 ±12	136 ±15	−129 ±22	132 ±11	−145 ±12	153 ±9
N12 b)	β	β	β	β	β	β

^a)While both TALOS and NCCN analysis favor the listed torsion angles, there appears to be a secondary minimum with β-sheet-like torsion angles (ϕ~ −80°; ψ~ 117°) that may also be consistent with our experimental data (ref. Figure S9 in the SI and main text below).

^b)Results for N12 reflect the secondary structure identified by CSI analysis (figure S4 in SI).