The metzincins – topological and sequential relations between the astacins, adamalysins, serralysins, and matrixins (collagenases) define a superfamily of zinc-peptidases. - Stocker, W; Grams, F; Baumann, U; Reinemer, P; Gomis-Ruth, FX; McKay, DB; Bode, W (Protein Science, 1995)