Figure 2.

Secondary structures deduced from NOE connectivities between imino proton resonances for the components and complete systems of Rz-3 and Rz-2. Colored circles indicate the residues for which the imino proton resonances were assigned. Colored lines indicate NOE connectivities. The dotted lines for Rz-3 show that the resonances were assigned, although a NOE cross-peak between them was not observed, by comparison with the corresponding resonances of Rz-2, for which not only a NOE cross-peak between them but also connectivities with the neighboring residues were observed. The residues and NOE connectivity lines are colored differently according to the stem. (A) Ea35 alone. A hairpin structure obtained by calculation is shown. (B) Ea35 + Eb16. (C) Rz-3. (D) E53. (E) Rz-2. In (D) and (E) only partial sequences and NOE connectivities which are different from those for Rz-3 are shown. (F) An alternative, minor secondary structure formed by mS8 and E53 obtained by free energy calculation.