Figure 1.

General structure of MMP groups with SP, propeptide, catalytic, and hemopexin domains.

Notes: The active site of zinc bound to the catalytic domain and the CS can be found in all MMPs. Gelatinase FN repeats are found in the catalytic domain of gelatinases. A furin-cleavage site (F) between the prodomain and catalytic domain can be found in MT-MMPs. Some MMPs have a TM domain attached to the hemopexin domain (MT-MMP). Other MT-MMPs have GPI-anchor domain.

Abbreviations: CS, cysteine switch; FN, fibronectin; GPI, glycosylphosphatidylinositol; MMP, matrix metalloproteinase; MT-MMP, membrane type-matrix metalloproteinase; SP, signal peptide; TM, transmembrane.