Xylella fastidiosa gene expression analysis by DNA microarrays

Abstract

Xylella fastidiosa genome sequencing has generated valuable data by identifying genes acting either on metabolic pathways or in associated pathogenicity and virulence. Based on available information on these genes, new strategies for studying their expression patterns, such as microarray technology, were employed. A total of 2,600 primer pairs were synthesized and then used to generate fragments using the PCR technique. The arrays were hybridized against cDNAs labeled during reverse transcription reactions and which were obtained from bacteria grown under two different conditions (liquid XDM 2 and liquid BCYE). All data were statistically analyzed to verify which genes were differentially expressed. In addition to exploring conditions for X. fastidiosa genome-wide transcriptome analysis, the present work observed the differential expression of several classes of genes (energy, protein, amino acid and nucleotide metabolism, transport, degradation of substances, toxins and hypothetical proteins, among others). The understanding of expressed genes in these two different media will be useful in comprehending the metabolic characteristics of X. fastidiosa, and in evaluating how important certain genes are for the functioning and survival of these bacteria in plants.

Xylella fastidiosa: An in vivo system to study possible survival strategies within citrus xylem vessels based on global gene expression analysis

“…The location and identity of each gene on the slide was defined in a text file, created with the aid of the Clone-Tracker2 program (Biodiscovery) by Travensolo et al (2008) and Travensolo et al (2009). The signal was quantified through ImaGene software (v.4.1, BioDisco-very), in which two images from the Cy3 and Cy5 fluorescent dyes were overlapped and the spots classified according to morphology and intensity.…”

“…We focused on the transcriptional activity of some genes related to biochemical processes involved in heat shock and antioxidant responses, toxins and detoxification processes as well as other possible mechanisms involved in bacterial survival. For this purpose, we used microarray analysis to identify global changes in gene expression patterns using a DNA microarray previously standardized by the Laboratory of Biochemistry of Microorganisms and Plants, by Travensolo et al (2008) and Travensolo et al (2009), including all genes identified in the X. fastidiosa genome.…”

Structure determination of a sugar-binding protein from the phytopathogenic bacteriumXanthomonas citri

“…Interestingly, although phylogenetically closely related, these species have quite different methods of attacking their hosts (Vojnov et al, 2010;Li & Wang, 2012). The importance of this protein in pathogenic bacteria is not clear, but Xac-MalE has been shown to be important during bacterial growth in Nutrient Broth and Tryptone Sucrose broth (TSE) enriched with glutamic acid (Soares et al, 2010), and its orthologue from X. fastidiosa was highly expressed in XDM2 medium, in which glucose was found at a concentration of 10 g l À1 (Lemos et al, 2003;Travensolo et al, 2009), suggesting an important function in sugar metabolism.…”

Identificação de genes com expressão modulada por estreptomicina e de genes associados à virulência e patogenicidade em Xylella fastidiosa

“…A estes estudos somam-se análises do transcritoma de X. fastidiosa que evidenciaram vários genes que estão potencialmente envolvidos na patogenicidade, virulência, competição e sobrevivência deste fitopatógeno (de de Souza et al, 2004; de Pashalidis et al, 2005;Koide, 2006;Koide et al, 2006b;da Silva Neto et al, 2007;Shi et al, 2007;da Silva Neto et al, 2008;Zaini et al, 2008; Killiny e Almeida, 2009a; Shi et al, 2009a;Shi et al, 2009b;Travensolo et al, 2009;Fogaça et al, 2010).…”