High-Throughput Microarray Comparative Genomic Analyses of Xylella fastidiosa Strains

• Author(s): Lin, Hong;
• Abstract: The Gram-negative, xylem-limited bacterium Xylella fastidiosa (Xf) causes economically important diseases of grapevine, citrus, almond, coffee, and many other horticultural crops and landscape plants. Currently, whole genome sequences for four strains are currently available, namely 9a5c (Citrus variegated chlorosis), Temecula-1 (Pierce's disease of grapevine), Dixon (almond leaf scorch disease) and Ann-1 (oleander leaf scorch disease). Comparative analysis of these four whole genome sequences showed that 76.2% of the total Xf genome is conserved among these four strains and identified significant variations (http//fresno.ars.usda.gov/citrusdisease/CVC_index.htm). Based on these results, we have developed a high-resolution Xf diagnostic system using spotted arrays as the platform with 'in silico' designed 60-mer probes for species (213 oligos) as well as strain identification (9a5c, 231 oligos; Ann1, 134; Dixon, 62 and Temecula-1,98). Preliminary tests using Xanthomonas spp. as the reference sample showed that 33% of the probes were Xf specific. This system can be applied for accurate, reliable and high throughput detection of genome-wide polymorphisms among different Xf isolates and define disease epidemics.
• Publication Date: Jul 2006
• Journal: Phytopathology