Arginine deiminase inhibits cell proliferation by arresting cell cycle andinducing apoptosis

We have previously demonstrated that arginine deiminase inhibits the prolif eration of vascular endothelial cells, but the mechanisms leading to growth inhibition leave remained unclear. We report here that low concentrations of arginine deiminase purified from Mycoplasma arginini inhibit proliferati on of various cultured cells by arresting the cell cycle in G(1) and/or S p hase with higher arginine deiminase concentrations leading to subsequent ap optosis, Our results demonstrate that arginine deiminase inhibits cell. pro liferation not only by depletion of arginine, but also by mechanisms involv ing the cell cycle and death signals. (C) 1999 Academic Press.