Contribution of Cell Outer Membrane and Inner Membrane to Cu~(2+) Adsorption by Cell Envelope of Pseudomonas putida 5-x

摘要

The role of outer and inner membrane in the Cu~(2+) adsorption process by gram-negative bacterium Pseudomonas putida 5-x, which was isolated from local electroplating effluent with high Cu~(2+) accumulating capability, was studied. The results indicate that both the outer and inner membrane exhibited high Cu~(2+) adsorption capacity. Outer and inner membrane contributed about 30-35% and 20-25% parts of adsorption capacity in Cu~(2+) adsorption by cell envelope of Pseudomonas putida 5-x, respectively. The total contribution of outer and inner membrane to Cu~(2+) adsorption by cell envelope was much greater than that of peptidoglycan layer. The relatively high phospholipid content in the outer membrane might result in its greater heavy metal ions adsorption capacity. The Cu~(2+) binding process by the outer and inner membrane of Pseudomonas putida 5-x is the adsorption processes and can be described with Freundlich isotherms.