bookmark KNOTTIN Provides standardized information on the small disulfide-rich proteins with a knotted topology. KNOTTIN concentrates sequences, structures and bibliographical data about inhibitor cystine knots (ICKs). This database is valuable given the specific properties of these miniproteins in terms of sequence, structure and function. It contains more than 3000 sequences of knottins. This web server also provides a user-friendly access to users’ knottin-specific tools.