Surface Characterization of Acidithiobacillus ferrooxidans Adapted to High Copper and Zinc Ions Concentration

Abstract

Changes in surface chemical properties of Acidithiobacillus ferrooxidans after adaptation to high copper and zinc ion concentration were studied by surface sensitive techniques such as zeta-potential, XPS and FT-IR measurements. The adapted bacteria were also characterized by their surface energies and adhesion capacities on different sulphide minerals. Their surface negative charge was decreased due to changes in the structure of bacterial surface layers. The metal ions adapted cells secreted more extracellular polymeric substances with a modified composition compared to unadapted ferrous ions grown cells. Bacterial cells hydrophilic property increased after adaptation and altered their adhesion behavior to sulphide mineral.

Keywords:

• bacteria
• copper
• zinc
• adaptation
• surface characterization

Acknowledgments

Financial support from the Kempestiftelsen Foundation in the form of a scholarship is gratefully acknowledged.