Sabine Matys

Bacterial-based bioremediation of uranium mining waste waters by using sol-gel ceramics

Cells, spores and the surface layer protein (S-layer) of the Bacillus sphaericus strain JG-A12, recovered from a uranium mining waste pile, were embedded in SiO2 matrices by using sol-gel techniques. Sorption and desorption of uranium and copper by the free biocomponents and the obtained biological ceramics (biocers) were investigated. The biocer with cells possesses the highest binding capacity, followed by the S-layer biocer and the spore biocer. For renewed use of the biocers, the bound uranium and copper can be completely removed by washing with aqueous citric acid.

Phage Display - A Promising Tool for the Recovery of Valuable Metals from Primary and Secondary Resources

The development of effective and ecofriendly processes for the recovery of critical elements poses a challenge for scientists all over the world. A novel approach is the generation of highly specific peptides that bind with high affinity to individual elements of interest. The peptides are selected by phage surface display (PSD) technology. In this study, PSD technology has been applied in two different approaches. The focus of the first approach was the identification of peptides that bind specifically to special particles of interest that are part of electronic scrap aiming towards the development of new recycling processes. In the second approach, metal ion binding peptides were isolated via PSD to use them for the targeted removal and enrichment of these elements from complex leaching solutions or from industrial waters. To address the economic production of peptides, the development of a new expression system is also part of this study.

Development of Metal Ion Binding Peptides Using Phage Surface Display Technology

Phage surface display technology is a useful tool for the identification of biosorptive peptides. In this work it is used for the identification of cobalt, nickel and gallium binding peptides. We present methods for the enrichment of metal ion binding bacteriophage clones from a commercial phage display library. Metal ion selective peptides are suitable to separate as well as concentrate cobalt and nickel from copper black shale leaching products (EcoMetals project) and gallium from industrial waste waters (EcoGaIn project). In contrast to common capture methods of specific binding phage for solid materials the ionic species have to be immobilized prior to the bio-panning procedure. This was realized by chemical complexation of the metal ions using commercial complexing agents on porous matrices. Moreover, an option to harvest non elutable strong binding phage is proposed.

Simplified Expression and Production of Small Metal Binding Peptides

Phage display for discovery of specific binding peptides is nowadays widely used in the pharmaceutical industry and in many biotechnological applications. Using state-of-the-art cloning techniques we developed an easy-to-use cloning and expression system, allowing the fast production of identified peptides while avoiding proteolysis.