Figure 5.

Determination of the torsion angles, (ϕ, ψ) for Ala¹⁵ and Gly¹⁶ residues in (AG)₁₅ with silk I structure from both 2D spin-diffusion NMR and REDOR experiments. The candidates of the torsion angles (red X marks) were determined from the observed 2D spin-diffusion NMR spectra in Figure 4. The atomic distances between ¹³C and ¹⁵N nuclei were determined to be 3.8 ± 0.1 Å for [1-¹³C]G¹⁴A¹⁵[¹⁵N]G¹⁶ and 3.2 ± 0.1 Å for [1-¹³C]A¹⁵G¹⁶[¹⁵N]A¹⁷, respectively from the observed REDOR data [22]. Reprinted with permission from ref. 22. Modified from ref. 22.