Metalloproteinase’s, enzymes involved in the process of hydrolysis and digestion of proteins, play vital roles in physiological processes and diseases such as Alzheimer’s disease, arthritis, osteoporosis and cancer. We have seen one of these metalloproteinase’s, the hCPA4 (human carboxypeptidase’s A4), is over expressed in some tumor cell lines. A team of researchers from the CSIC and the Autonomous University of Barcelona have solved the atomic structure of this enzyme complex formed and Latex in, the only known endogenous inhibitor of Metallocarboxypeptidases.

The Latex in, also known as ECI (endogenous inhibitor of carboxypeptidase’s), inhibits hCPA4, a member of the subfamily A / B of the MCP (Metallocarboxypeptidases) showing the characteristic bend alpha / beta-hydrolyses. The human Latex in consists of two topologically equivalent sub domains, consisting of an alpha helix is covered by a curved beta sheet. These sub domains are packed against each other through the helices and linked by a connecting segment consisting of one third alpha helix. The enzyme binds to the interface between both sub domains. Despite its large contact area, the complex shows a low specificity, which explains the flexibility of the Latex in in inhibiting MCP all type A / B of vertebrates tested. Have identified several sequences assigned to various tissues and organs in vertebrate genomes are very similar to Latex in, so the authors suggest that may constitute a family of inhibitors.