A novel yeast bioassay for high - throughput screening of 3 matrix metalloproteinase inhibitors

24 25 Diverse malfunctions in the expression and regulation of matrix metalloproteinases (MMPs) are 26 often the cause of severe human diseases, bringing the identification of specific MMP-inhibitors 27 into major focus particularly in anti-cancer treatment. Here we describe a novel bioassay based 28 on recombinant yeast cells (Pichia pastoris) which express, deliver and incorporate biologically 29 active human MMP-2 and MMP-9 to the yeast cell surface. Using Sed1p for cell wall targeting 30 and covalent anchorage a highly efficient bioassay was established which allows high31 throughput screening and subsequent validation of novel MMP inhibitors as potential anti32 cancer drugs. In addition, we developed a straightforward synthesis of a new aspartate-derived 33 MMP-inhibitor active in the nM range, bearing an amino functionality which should allow the 34 introduction of a wide range of side chains to modify the properties of these compounds. 35