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08:44
Visualization of Twitching Motility and Characterization of the Role of the PilG in Xylella fastidiosa
Published on: April 8, 2016
Morphological evidence for phages in Xylella fastidiosa
Jianchi Chen1, Edwin L Civerolo
1San Joaquin Valley Agricultural Sciences Center, Agricultural Research Services, United States Department of Agriculture, Parlier, California, 93648, USA. jianchi.chen@ars.usda.gov
Virology Journal
|June 10, 2008
Summary
This study reports the first physical evidence of active bacteriophages released by Xylella fastidiosa bacteria. Transmission electron microscopy revealed various phage particles, including icosahedral and filamentous types, associated with this plant pathogen.
Area of Science:
- Microbiology
- Virology
- Plant Pathology
Background:
- Xylella fastidiosa is a Gram-negative bacterium causing significant plant diseases.
- Previous evidence for Xylella fastidiosa phages was primarily genomic.
- No physical evidence of phage particles released by Xylella fastidiosa had been reported.
Purpose of the Study:
- To provide the first physical evidence of bacteriophage particles associated with Xylella fastidiosa.
- To characterize the morphology of these phage particles using transmission electron microscopy.
Main Methods:
- Culturing Xylella fastidiosa strain Temecula-1 in PW broth.
- Transmission electron microscopy (TEM) of bacterial cell pellets and purified preparations.
- Analysis of ultrathin sections and CsCl density gradient fractions.
Main Results:
- Presumptive phage particles were observed in bacterial cultures.
- Icosahedral particles (45 nm and 30 nm) and filamentous particles (17 x 120–6,300 nm) were identified.
- Both non-tailed and tailed phage particles were detected.
Conclusions:
- This study provides the first direct physical evidence of active phages released by Xylella fastidiosa.
- The observed phage particles resemble those found in several known bacteriophage families.
- These findings support the existence of active phages within Xylella fastidiosa populations.
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