The NMR on peptide samples was performed at 303 K. The peptide samples were obtained using 1 mM unlabeled peptides and 100 mM DPC-d38 (POCH S.A. Poland) in 90%/10% H2O/D2O at pH 5.0. The experimental data were recorded using Varian Inova 500 ( 1 H frequency 500.606 MHz) equipped with three channels, z-gradient unit and 1 H/ 13 C/ 15 N triple probe head with inverse detection. The conducted homonuclear 2D NMR experiments included TOCSY, performed with mixing time 15 and 80 ms, NOESY, with mixing time 120 ms, and ROESY, with mixing time 400 ms. Excitation sculpting DPFGSE pulse block was used to suppress water signals in all acquired homonuclear data sets. The 2D homonuclear data were additionally supplemented with heteronuclear 2D 1 H-13 C HSQC (tuned independently to aliphatic and aromatic regions).The 2D 1 H-15 N HSQC NMR experiments acquired on natural abundance of 13 C and 15 N nuclei.