Kinetic and structural studies on the adsorption of metals and actinides on cell surfaces by using multi-layer systems as a model of bacterial cell walls
The adsorption and desorption behavior of metals and actinides, e.g. uranium were examined in bacterial cells (isolates of the pile Haberland nearby Johanngeorgenstadt, Saxony) as a total system as well as bacterial surface layer proteins (S-layers) as a prominent component of the cell surface.
Bacterial cell walls are very complex, consisting of lipids, teichoic or teichuronic acids, proteins, sugars etc. This complexity makes it difficult to understand binding events on cells. Conversely, the investigation of interactions with single components gives detailed information on the complexation with biomolecules, but conclusions to the total system cannot be made seriously. In addition, previous studies have focused on the free biomolecules, but not on layers, such as those found in the cell wall. In the PhD thesis, it is intended to develop a multi-layer system, which is composed of all major cell wall components, serving as a simplified model for cell walls of Gram-positive bacteria. This model is used to monitor binding processes and to investigate the effect of binding events on the structures of biomolecules. For this study the quartz crystal microbalance (QCM-D) in combination with atomic force microscopy (AFM) and other analytical methods are used to track these processes in biological interfaces.