Date of Award


Publication Type

Master Thesis

Degree Name



Biological Sciences


Biology, Molecular.


Cotter, D.




Some of the world's most notorious fungal pathogens belong to the phylum Oomycota. Saprolegnia and Achlya, both water-borne members of this phylum, have been implicated as pathogens of amphibians, fish and rice. Like all fungi, these organisms require nutrient uptake by external enzymatic degradation. It has long been hypothesized that such external enzymes may also play a crucial role in pathogenicity by degrading host structure and defenses, while providing nutrients for the growing pathogen as it penetrates deeper into host tissues. Proteases, enzymes that specifically degrade proteins, may serve a crucial role in animal host penetration through fibrous structural proteins. In this study, gelatin SDS-PAGE analysis has demonstrated multiple bands of inducible extracellular proteolytic activity among Achlya ambisexualis, and two species of Saprolegnia, including a species recently isolated as the cause of "winter kill" in Mississippi fish farms (Bly et al. 1992). This inducible proteolytic activity among the Saprolegniales may provide answers to their mechanism of potential pathogenicity. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2001 .K35. Source: Masters Abstracts International, Volume: 40-03, page: 0652. Adviser: David A. Cotter. Thesis (M.Sc.)--University of Windsor (Canada), 2001.