Purification and characterization of the human stromelysin catalytic domain expressed in Escherichia coli

Human stromelysin is a member of the matrix metalloproteinase family involved in connective tissue degradation. The stromelysin catalytic domain (SCD) lacking both propeptide and C-terminal fragment was expressed in Escherichia coli in soluble and insoluble forms. The insoluble SCD was refolded to the active form in high yield. The protein showed remarkable thermal stability and was able to cleave a thiopeptolide substrate and its natural substrate proteoglycan. The stable and active 20-kDa protein provides an opportunity to elucidate the structure as well as the mechanism of catalysis and inhibition for matrix metalloproteinases.