Figure 1.

Sequence alignment and structures of different cyclotides belonging to the Möbius (kalata B1, pdb: 1NB1), bracelet (cycloviolacin O1, pdb: 1NBJ) and trypsin inhibitor (MCoTI-II, pdb: 1IB9) subfamilies. Disulfide connectivities and backbone-cyclization are shown in red and orange, respectively. The six Cys residues are labeled with roman numerals whereas loops connecting the different Cys residues are designated with arabic numerals. Conserved Cys and Asp/Asn (required for backbone cyclization in nature) residues are marked in yellow and light blue, respectively. Molecular graphics were created using Yasara (www.yasara.org).