Lipoxygenase Inhibitors Shift the Yeast/Mycelium Dimorphism in Ceratocystis ulmi

Authors

• Ellen C. Jensen, University of Nebraska-LincolnFollow
• Clyde Ogg, University of Nebraska-LincolnFollow
• Kenneth W. Nickerson, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

8-1-1992

Comments

Published in APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Aug. 1992, p. 2505-2508 Vol. 58, No. 8. Copyright C) 1992, American Society for Microbiology. Used by permission.

Abstract

The yeast-mycelium dimorphism in Ceratocystis ulmi, the causative agent of Dutch elm disease, was switched by gossypol, nordihydroguaiaretic acid, and propylgallate. In each case the mycelial form was converted to the yeast form. These compounds are recognized lipoxygenase inhibitors. Inhibitors of cyclooxygenase and thromboxane synthetase did not cause mycelia to shift to the yeast form. We suggest the following two-part hypothesis: (i) that lipoxygenase is a target for antifungal antibiotics and (ii) that many phytoalexins (antimicrobial compounds of plant origin) are targeted toward fungal lipoxygenases. In addition, in a study to determine potential lipoxygenase substrates, a fatty acid analysis indicated that C. ulmi conidiospores contained high levels of oleic, linoleic, and linolenic acids but no arachidonic acid.