Enzymes that initiate a flip-flop action in membrane lipids have been designed by Bradley Smith and his research group at the University of Notre Dame. These translocases may lead to advancements in the search for chemotherapeutic agents.

The distribution of phospholipids on the inner and outer surfaces of cell membrane surfaces is maintained by membrane-bound translocases, which catalyze the translocation of phospholipids from one side of the membrane to the other.

These enzymes operate by forming supramolecular complexes with phosphatidyl serine head groups of membrane lipids; these complexes can then diffuse across the membrane. The synthetic translocases were remarkably effective in human red blood cells.

Raising the concentration of certain phospholipids, namely phosphatidylserines, on the cell surface induces biological processes such as blood coagulation and programmed cell-death. One of Smith's enzymes prompted phosphatidylserine to flop from the inside to the outside of the membrane. The potential to induce cell death could be a great development in chemotherapeutic research enabling targeting of diseased cells for clearance.

Eleanor Riches