IBR   13079
INSTITUTO DE BIOLOGIA MOLECULAR Y CELULAR DE ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Role of a RNA-binding protein in Xanthomonas citri subsp. citri pathogenicity
Autor/es:
BELTRAMINO, M.; PETROCELLI, S.; MOYANO, L.; ORELLANO, E.G.
Lugar:
Rosario
Reunión:
Congreso; IX Congreso de Microbiología General; 2013
Institución organizadora:
Sociedad Argentina de Microbiología General (SAMIGE)
Resumen:
Small RNAs (sRNAs) have been recognized for being important gene regulators in bacteria. sRNAs play several essential roles in multiple cellular processes. The Sm-like Hfq protein is a key factor in the processes regulated by RNAs. This protein promotes the sRNAs and mRNA interaction and it also participates in polyadenylation and translation of mRNAs. The Hfq deficiency has a great impact in the physiology of several bacteria. In addition was reported that this protein is involved in the virulence processes in many animal pathogens. However, little is known about sRNAs and Hfq protein in bacterial plant pathogens. Xanthomonas citri subsp. citri (Xac) is the bacterium responsible of citrus canker, a severe disease that affects most commercial citrus cultivars, causing significant crop losses worldwide. The aim of this work was to study the role of Hfq protein in the bacterial physiology and in the pathogenicity process during the interaction of Xac with its host plant Citrus sinensis. For that purpose we have constructed three Xac strains: the Hfq over-expressing (Xac-pBBRhfq), the knockout hfq (XacΔhfq) and the complementant strain (cXacΔhfq). The bacterial motility, the adhesion to biotic and abiotic surfaces, the biofilm formation and the growth curves were evaluated for these strains demonstrating that the Hfq protein is implicated in the control of these features. We also analyzed the Hfq expression in XVM2, a minimal medium that mimics the apoplastic space, and in SB, a rich medium. An increased expression of this gene was observed in the XVM2 medium. Finally, we analyzed the interaction of the Xac-pBBRhfq, XacΔhfq and cXacΔhfq bacterial strains with orange plant leaves, observing a reduction in disease symptoms with the knockout hfq bacteria suggesting a role of Hfq protein in the pathogenesis process during citrus canker disease.