The Antitoxin Is Important Not Only for Human Pathogens: Evidence of Its Role in the Plant Pathogen subsp. .

subsp. causes citrus canker disease worldwide in most commercial varieties of citrus. Its transmission occurs mainly by wind-driven rain. Once reaches a leaf, it can epiphytically survive by forming a biofilm, which enhances the persistence of the bacteria under different environmental stresses and plays an important role in the early stages of host infection. Therefore, the study of genes involved in biofilm formation has been an important step toward understanding the bacterial strategy for survival in and infection of host plants. In this work, we show that the toxin-antitoxin (TA) system, which was previously identified only in human bacterial pathogens, is conserved in many spp. We further show that in , is involved in important processes, such as biofilm formation, exopolysaccharide (EPS) production, and motility. In addition, we show that plays a role in survival and virulence in host plants. Thus, this mechanism represents an important bacterial strategy for survival under stress conditions. Very little is known about TA systems in phytopathogenic bacteria. , in particular, has only been studied in bacterial human pathogens. Here, we showed that it is present in a wide range of sp. phytopathogens; moreover, this is the first work to investigate the functional role of this TA system in biology, suggesting an important new role in adaptation and survival with implications for bacterial pathogenicity.