Beneficial association of Pseudomonas aeruginosa in roots of Typha latifolia present in the mining tailings wetland.

• DOI: https://doi.org/10.22533/at.ed.973532517027

• Palavras-chave: P. aeruginosa, biosurfactants, resistance genes, heavy metals, wetland.

• Keywords: P. aeruginosa, biosurfactants, resistance genes, heavy metals, wetland.

• Abstract:

  Pseudomonas aeruginosa is a bacterium capable of living in diverse environments, producing biosurfactants, fixing nitrogen, tolerating heavy metals, and is capable of transferring resistance genes to Pb, Cd and As by means of plasmids. These characteristics make it an excellent proposal for bioremediation studies in sites contaminated with metals. The objective of this study was to search for bacterial strains associated with the rhizosphere of T. latifolia with biotechnological potential. For this purpose, strains were isolated from the rhizosphere of the aquatic plant and only those capable of producing biosurfactants by foam production in PPGAS broth, droplet collapse, IE24h were selected. MIC to Pb, Cd and As was determined, nitrogen fixation was detected on NFb agar, plasmid extraction was performed by Kieser's method, and PCR detection of arsA, cadA and pbrA genes. Only four strains PAR1, PAB12, J2 and J3 able to produce biosurfactants and fix nitrogen were isolated. They did not present plasmids and only amplified Pb and Cd resistance genes (cadA and pbrA). These strains are proposed for further study and use in wetland bioremediation processes in sites contaminated with heavy metals.