Figure 1.

Comparison of WT, H48C, and H48C-4MI. (a) Average backbone structure WT and H48C-4MI over a 20 ns MD simulation and expansion showing H-bond interactions with loop 1 and β-strand 4 that are common to H48 and H48C-4MI. Secondary structures and relevant residues are labeled. Part (b) shows an overlay of ¹H,¹⁵N HSQC spectra for WT, H48C, and H48C-4MI. Peaks are labeled to indicate the RNase A variant. The expanded region shows a close up view of F120 and H12 showing the proximity of the H48C-4MI peak to WT, relative to the H48C residues. Contour levels were adjusted to account for different [RNase A].