FIGURE 12.

I315G mutation enhances the CypA-catalyzed cis/trans isomerization on Pro³¹⁴. A and C, tables summarizing all the CypA-catalyzed exchange processes that we have detected between the different proline populations in PepD2-WT (A) and in PepD2-I315G (C), respectively. B and D, superimposition of two-dimensional ¹H,¹⁵N-Hα(Cα)N NMR spectra with a Cα_Z.N_Z magnetization transfer period (150 ms) in absence (in red) or in presence of catalytic amount of unlabeled CypA (in blue), recorded on ¹⁵N,¹³C-PepD2-WT (B) and ¹⁵N,¹³C-PepD2-I315G (D). B and D correspond to zoomed regions centered on Pro³¹⁴ and Pro³²³ resonances. NMR exchange cross-peaks connecting the trans (T) and cis (c) conformers of Pro³¹⁴ (orange dashed frames and open circles) are more intense in the case of PepD2-I315G (D) than with PepD2-WT (B), whereas the normalized cross-peaks corresponding to the Pro³²³ isomerization (black dashed frames) are of the same intensity.