Use of spectroscopic and microscopic methods to reveal the evidence of U(VI) sorption on Acidovorax facilis isolated from subsurface environments

U(VI) biosorption experiments were performed using isolated Acidovorax facilis cell. From TRLFS measurements it can be concluded that phosphoryl groups are the main binding sites for uranyl, located in the lipopolysaccharide (LPS) unit in the outer membrane by Gram-negative Acidovorax facilis cells. In addition, EF-TEM/EELS studies provide microscopically and spectroscopically evidence of U sorbed at the outer membrane of Acidovorax facilis cells by showing high electron density and U ionization intensity peaks. The results support the TRLFS measurements and contribute to a better understanding of the binding mechanisms of U(VI) on Acidovorax facilis cells.