Supplementary Figure 8: Water-to-peptide polarization transfer data.
From: The peptide hormone glucagon forms amyloid fibrils with two coexisting β-strand conformations
a, Pulse sequence for transferring water 1H polarization to the protein and detected through 2D 13C-13C correlation spectra (Wang, T., et al., J. Am. Chem. Soc. 139, 6242-6252, 2017). Control spectra have a 1H T2 filter of 0 ms, whereas water-edited spectra have a T2 filter of 1.4–1.7 ms. All spectra were collected with a 2.25 ms 1H-1H tmix period. b-d, Aliphatic regions of the water-edited 2D 13C-13C correlation spectra of b, sample 7c, c, sample 8c, and d, sample 9c. Representative 1D cross sections of the sample 7c 2D spectrum illustrate the differential water-transferred intensities for the same residue in different conformers. For example, T5 in conformer I has lower water-transferred intensities than T5 in conformer II, indicating that T5 lies in a dry interface in conformer I but is water-exposed in conformer II.
