FIGURE 3.
Secondary structure of IC:1–143. 3J-coupling constants are grouped as <5 Hz (open circles) for helical structure, between 6 and 8 Hz (filled black circles) for random coil, and >8 Hz (filled gray circles). Sequential amide-amide connectivities are shown short and medium range NOEs. Secondary chemical shifts for Cα and Cβ atoms are presented in bar plot format below the inter-residue NOE connectivities. The secondary structure estimated from 3J-coupling values and secondary chemical shifts is plotted above the sequence and includes the following: helices (solid cylinders), nascent helix (outlined cylinder), and random coil conformation (dotted line).