Nicole Thunes, PhD candidate in the Department of Biological Sciences at UW-Milwaukee, will present a talk about her research entitled, “Gliding Motility, Protein Secretion, and Flavobacterium columnare Virulence.”

Flavobacterium columnare causes columnaris disease in many economically important freshwater fish. Mutants lacking the type IX protein secretion system (T9SS) fail to cause disease. It is unknown which of the many proteins secreted by the T9SS are critical for disease. In addition to secretion of individual proteins, the F. columnare T9SS is also needed for gliding motility. My research explored the roles of individual secreted proteins and of gliding motility in virulence. Several secreted lytic proteins and peptidases that contribute to F. columnare virulence were identified. To untangle the roles of secretion and motility in virulence, we also constructed mutants defective for secretion but competent for motility, and mutants defective for motility but competent for secretion, and analyzed these for virulence. Results indicate that secretion and motility are both important for virulence in zebrafish and in rainbow trout. Our results suggest strategies to control this common fish pathogen, as a step toward more sustainable and environmentally-friendly freshwater aquaculture. 

This presentation will begin at 4:00 PM in Lapham N101 and via Microsoft Teams, preceded by an informal Q&A from 3:45 – 4:00 PM. If you are unable to attend in person, click here to join the virtual presentation.