The disulfide knot is a ring consisting of two disulfide bonds (1-15 and 8-20) and the connecting backbone, through which a third disulfide bond (14-31) passes.
A disulfide knot is a three-dimensional structure formed by three disulfide bonds: one pair (1-15 and 8-20) and a connecting backbone, with a third disulfide bond (14-31) passing through it.