The plant pathogenic bacterium Xylella fastidiosa is limited to colonizing xylem vessels, the water conduits of plants.  It causes economically important diseases by developing cell aggregates and biofilms that block xylem sap flow. Because temporal and spatial activities of the bacteria can not be viewed microscopically in planta, microfludic devices have been developed to mimic features of plant xylem vessels where the bacteria can be observed. Using such devices, we discovered that X. fastidiosa migrate upstream via type IV pili-mediated twitching motility and have subsequently confirmed such movement in planta. The microfluidic chambers are being used to further investigate various properties of the pili and their roles in cell attachment, motility, aggregation and biofilm formation.

Leonardo De La Fuente received his B.Sc. degree in Biochemistry and his M.S. degree in Microbiology from the University of the Republic ( Montevideo , Uruguay ).  In 2001, Leo moved to the U.S.A. and received his Ph.D. in Plant Pathology from Washington State University . For his Ph.D. thesis work, Leo studied ecological and physiological aspects of biocontrol of plant root-associated bacteria. Leo is currently a Postdoctoral Research Associate in the Department of Plant Pathology at Cornell University ( Geneva ), working with Harvey Hoch and Tom Burr.