INTECH   27907
INSTITUTO TECNOLOGICO DE CHASCOMUS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
SECRETION OF PUTRESCINE BY PSEUDOMONAS SYRINGAE FUNCTIONS AS AN ANTIOXIDANT DEFENSE DURING PLANT INVASION
Autor/es:
LEANDRO SOLMI; OSCAR RUIZ; MATIAS FERNANDO ROMERO; FRANCO RUBEN ROSSI; ANDRÉS GÁRRIZ
Lugar:
Córdoba, Córdoba
Reunión:
Congreso; XXII Reunion Argentina XVI Congreso Latinoamericano de Fisiología Vegetal; 2018
Institución organizadora:
Sociedad Argentina de Fisiología Vegetal
Resumen:
Polyamines such as putrescine, spermidine and spermine are important for virulence in phytopathogens. Our previous analysis demonstrated that P. syringae induces the synthesis and secretion of putrescine during pathogenesis. This process contributes to the accumulation of putrescine at the apoplast, the site where P. syringae multiplies and confronts a high concentration of oxidative molecules produced by plants as a defense response. In this work, we were prompted to explore whether the secretion of this polyamine by P. syringae functions to cope with oxidative stress. Our analysis demonstrated that bacterial growth is affected by sub lethal concentrations of H2O2. In addition, P. syringae induced the secretion of putrescine in response to this oxidative environment, leading to the increase in its concentration at the extracellular space. In turn, the fractions of intracellular and membrane-bound polyamines remained unaltered. Disruption of polyamine biosynthetic genes led to an increase of intracellular reactive oxygen species, demonstrating that these compounds are involved in maintaining redox homeostasis. Nevertheless, the addition of putrescine to culture media was not able to ameliorate the effects of oxidative stress neither restore bacterial growth in the presence of H2O2. These results shed more light to the roles played by polyamines during bacterial pathogenesis.