Differential effects of salinity and osmotic stress on the plant growth-promoting bacterium Gluconacetobacter diazotrophicus PAL5.

Plant growth-promoting bacteria (PGPB) represent a promising alternative to the massive use of industrial fertilizers in agriculture. Gluconacetobacter diazotrophicus is a PGPB that colonizes several plant species. Although this bacterium is able to grow at high sucrose concentrations, its response to environmental stresses is poorly understood.

Essential role of the czc determinant for cadmium, cobalt and zinc resistance in Gluconacetobacter diazotrophicus PAl 5.

The mechanisms of cadmium, cobalt and zinc resistance were characterized in the plant-growth-promoting bacterium Gluconacetobacter diazotrophicus PAl 5. The resistance level of the wild-type strain was evaluated through the establishment of minimum inhibitory concentrations (MIC) of the soluble compounds CdCl2·H2O, CoCl2·6H2O and ZnCl2. Gluconacetobacter diazotrophicus PAl 5 was resistant to high concentrations of Cd, Co and Zn, with MICs of 1.

Identification and characterization of Gluconacetobacter diazotrophicus mutants defective in the solubilization of phosphorus and zinc.

Gluconacetobacter diazotrophicus is a plant-growth-promoting bacterium, which is able to colonize sugarcane and other plant species of economic importance. The potentially beneficial effects promoted by this bacterium on plants are nitrogen-fixation, production of phythormones, action against pathogens and mineral nutrient solubilization. In this study, the molecular mechanisms associated with phosphorus and zinc solubilization were analyzed.