Figure 6.

Detection of a native-like folding intermediate for mβ₂m. (A) The ¹H–¹⁵N SOFAST HSQC spectrum of mβ₂m collected 3 min after refolding was initiated from the partially folded state at pH 3.6 (blue), overlaid with the ¹H–¹⁵N SOFAST HSQC of native mβ₂m (collected after 90 min) (gray). Peaks corresponding to the molten globule I₁ state are colored in pink. (B) Per residue combined ¹H–¹⁵N chemical shift differences between the native and the I_T state of mβ₂m, using the spectra displayed in (A). Blue dots represent residues for which assignments are missing in the native spectrum. Residues that show chemical shift differences greater than 1 ppm (dashed line) are colored yellow, those that show chemical shift differences less than 1 ppm are shown in gray, and residues that are broadened beyond detection in the 3 min spectrum are colored red. The strucure of mβ₂m colored in the same color scheme is shown on the right.