Solution structure of the macrocyclic squash trypsin inhibitor MCoTI-II,the first member of a new family of cyclic knottins

摘要

Squash trypsin inhibitors are small disulfide-rich proteins (28-30 residues,6 cysteines).Their 3D structures revealed that one disulfide crosses the macrocycle formed by the other two disulfide bridges and the interconnecting backbone,hence the term "knottins".This particular topology has been found in a number of cystine-rich peptides with diverse biological activities isolated from plants or animals.