Inhibition of human stromelysin by peptides based on the N-terminal domain of tissue inhibitor of metalloproteinases-1.

The tissue inhibitors of metalloproteinases (TIMPs) represent a family of naturally occurring protein inhibitors of stromelysin and other members of the family of matrix metalloproteinases. A series of peptides based on the N-terminal sequence of natural TIMP-1 was synthesized and assessed for inhibitory activity against purified human stromelysin. Inhibitor peptides were identified in the loop (bounded by the disulfide bonds [C3-C99] and [C13-C124]), e.g., [C3(Acm)-C13], (IC50, 42 microM). It was established that inhibition was due to the free sulfhydryl group of either C13 or C124. However, peptides within [C70(Acm)-C98(Acm)] inhibited stromelysin independently of zinc co-ordination by cysteine. The binding epitope in TIMP-1 may be discontinuous and comprised of sequences from at least 2 loops.