POLYPHOSPHATE ROLE IN Gluconacetobacter diazotrophicus ABIOTIC STRESS RESISTANCE AND BIOFILM FORMATION

GRILLO PUERTAS, MARIANA; DELAPORTE-QUINTANA, PAOLA; RAPISARDA, VIVIANA ANDREA; PEDRAZA, RAÚL O

Córdoba

Congreso; 52th Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2016

SAIB

Gluconacetobacter diazotrophicusis a plant growth promoting bacterium able to colonize several plant species of economicimportance. Its beneficial effects on plants are nitrogen-fixation, action against pathogens and mineral nutrient solubilization. The useofG. diazotrophicusas a biofertilizer requires a study of its physiological properties, including how this bacterium responds to theextracellular environment. We have previously shown that media phosphate (Pi) concentration modulate polyphosphate (polyP) levelsinEscherichia colicells affecting several cellular features. The aim of this work was to study the possible physiological changes inG.diazotrophicusPal5 due to variations in growth media Pi concentration that may modulate intracellular polyP levels. Cells grown in high Pi reached higher OD values than those grown in sufficient Pi. In high Pi media, the cells accumulate high polyP levels anddegraded it in stationary phase. This feature was accompanied with the improvement in survival, resistance to different stress agents(NaCl, H2O2, Cu(II)salts and copper-related fungicides) and biofilm formation in abiotic and biotic surfaces. Our findings on therelationship between media Pi concentration, resistance, biofilm formation and polyP levels contribute to elucidate the importance ofPi or its metabolites as signals for survival and colonization in this bacterium