Figure 2.

Structural ensembles of the two PrgK_19–92 conformers. Line representation of the backbone atoms for the twenty lowest‐energy models for PrgK_19–92 in the (A) conformer A and (B) conformer B, obtained with CS‐Rosetta.20 (C) The two averaged structures are overlaid in cartoon representation, with conformer A in green and conformer B in cyan. The only significant difference lies at their C‐termini, where residues 75–78 of the linker are ordered in conformer A but not in conformer B. (D) The heteronuclear NOE values for the two populations of PrgK_19–92 plotted versus sequence, with the secondary structure shown at the bottom. Decreasing NOE values indicate increasing mobility of the ¹H^N‐¹⁵N bond on the sub‐nsec timescale. This confirms that residues 75–78 (shaded rectangle) are ordered in conformer A, but flexible in conformer B