Phenotypic and Molecular Characterization of Two Enterobacter Strains, Isolated from a Phytodepuration- Based Wastewater Treatment Plant in Prato (Tuscany, Italy)

Environmental pollution and presence of pollutants in water environments are main concerns for society worldwide. Environmental-friendly methods for the clearance of these compounds are continuously developed and improved to provide efficient and economical solutions. Phytodepuration has been exploited over the years, since it is based on the remedying abilities of plants and their rhizospheric microorganisms. In this preliminary work, we describe the phenotypic and molecular characterization of two Enterobacter strains isolated from a wastewater treatment plant, which uses the common reed Phragmites australis. Both strains were able to resist against multiple antibiotics, growing in the presence of a wide range of pH and several pollutants (such as those containing metals and metalloids). They were also able to produce indole-3- acetic acid and to use diesel fuel as the sole carbon and energy source. In conclusion, this work represents the beginning for a deep characterization of the P. australis microbiota used for phytodepuration, to discover new metabolic abilities. These results might be used for the engineering of super-degrader strains with advantageous features such as a broad degradation activity against recalcitrant compounds and ability to grow in polluted environments.