Matrix metalloproteinases (MMPs) or matrixins may play a role in the degradation and remodeling of the extracellular matrix (ECM) during development or in response to stresses (By similarity). Active on Mca-KESAbuNLFVLKDpaR-NH(2) (QF75) and, to some extent, on McaPLGLDpaAR-NH(2) (QF24), myelin basic protein (MBP) and beta-casein (PubMed:24156403). Binds 1 zinc ion per subunit. Repressed by acetohydroxamic acid (AHA). Optimum pH is 7-8. Optimum temperature is 35 degrees Celsius. Mostly expressed in leaves, roots and stems, and, to a lower extent, in flowers. The conserved cysteine present in the cysteine-switch motif binds the catalytic zinc ion, thus inhibiting the enzyme. The dissociation of the cysteine from the zinc ion upon the activation-peptide release activates the enzyme. Belongs to the peptidase M10A family. Matrix metalloproteinases (MMPs) subfamily.