Submitted to: American Phytopathology Society
Publication Type: Abstract Only
Publication Acceptance Date: August 12, 1999
Publication Date: N/A
Technical Abstract: Trichothecenes are potent inhibitors of cytoplasmic protein synthesis. These toxins can effect the severity of plant diseases such as wheat head scab. While many trichothecene-producing fungi share the initial biosynthetic intermediates, Fusarium sp. are unique in the production of trichothecenes containing an oxygen function at C-3. Although the initial trichothecene and the final products have a C-3 hydroxyl group, the intermediate steps are acetylated at C-3. In order to test the proposal that trichothecenes with a C-3 hydroxyl are more toxic to plants, we devised a test using Chlamydomonas reinhardtii for measuring the relative phytotoxicity of various pathway intermediates. Seven pairs of trichothecenes with either a C-3 hydroxyl or C-3 acetyl group were assayed on the growth of Chlamydomonas. Our results confirm that trichothecenes acetylated at C-3 were far less toxic to Chlamydomonas than those with a C-3 hydroxyl group.