Effect of 5-fluoro-2'-deoxyuridine on toxin production and cell cycle regulation in marine dinoflagellate, Alexandrium tamarense

The effect of metabolic inhibitor, 5-fluoro-2'-deoxyuridine (FUdR) on toxin production and the cell cycle of marine dinoflagellate, Alexandrium tamarense, was investigated. Compared to untreated cells, FUdR at 3 mu M (p < 0.05) to 300 mu M (p < 0.01) inhibited the cell proliferation and toxin production in a dose-dependent manner for A. tamarense cultured in modified T-1 medium. FUdR at 203 mu M resulted in cell cycle arrest at the S phase at day 4 and toxigenesis was inhibited after day 2. The toxin profiles of the FUdR-treated cultures were similar to those of the control culture. These results suggest that FUdR inhibits saxitoxin (STX) biosynthesis in the early stage of the pathway. This report is the first to demonstrate the inhibition of toxin production in A. tamarense by a nucleoside analog. (C) 2013 Elsevier B.V. All rights reserved.