XYLELLA FASTIDIOSA GROWTH ON CHARD2, 3G10R AND XF-26 CHEMICALLY-DEFINED MEDIA

• Author(s): Andersen, Peter; Leite, Breno; Marques, Lyriam; Olson, Merle;
• Abstract: Pierce`s disease (PD) in grapevines is caused by the bacterium Xylella fastidiosa (Xf). Xf is injected into xylem vessels by leafhoppers. Xf can grow planktonic (free cells) or can form aggregates or biofilm (colonies). Growth and biofilm formation of UCLA and STL PD strains was compared in three chemically-defined media, Xf-26 (22 components), CHARD2 (10 components) and 3G10R (9 components). PW(+), a rich non-defined medium, was used as a control. Both planktonic growth and biofilm formation were assessed during the incubation period. CHARD2, which has the amino acid cysteine as a component, was by far the best medium inducing biofilm formation. CHARD2 and Xf-26 differed in planktonic growth; CHARD2 exhibited no detectable planktonic growth, whereas Xf-26 cultures were predominantly planktonic. 3G10-R performance was below the expectations, since this medium has performed satisfactorily before as an aggregation inducer. 3G10-R has reduced glutathione (reducing agent), however it contains glucose, which is not present in CHARD2. We hypothesize that the redox environment, in each medium, induced the differences in biofilm architecture verified.
• Publication Date: Dec 2005
• Journal: 2005 Pierce's Disease Research Symposium