S-Layer Directed Nanoscale Fluid Mechanics
Abstract
Two-dimensional crystalline S(urface)-layers are the most commonly observed cell surface structures in prokaryotic organisms (Bacteria and Archaea). Although no general biological function has been found so far, many of the specific functions assigned to S-layers depend on the complete coverage of the bacterial cells. However, a striking feature of S-layers are their excellent anti-fouling properties as already successfully applied in microfluidic devices. In this context, we assumed that this effect may also be related to the hydrodynamic surface properties of S-layer coated bacterial cells in water. The investigation of both phenomena, anti-fouling and flow resistance in water, as benefits for the bacterial cell was the main objective of this research project. The work was based on the assumption that the water layers directly associated with the nanometric topography and surface charge distribution of the S-layer protein matrix play an important. The change in the wetting behavior of the S-layer depending on the dried or wet state and, in particular, on the crystallinity of the layer were the two main results of the contact angle measurements. Further on, the anti-fouling properties of S-layers were further confirmed by binding experiments with serum albumin. We continued our investigation of the non-classical pathway of S-layer crystal growth on solid supports. QCMD and real time AFM demonstrated that adsorption of S-layer monomers from solution is completed within 5 minutes, the amount of adsorbed protein was sufficient for the generation of a complete monolayer but prolonged incubation in buffer containing CaCl2 mandatory for conversion into the crystalline structure. In this context, we had been able to establish micro molding in capillaries and micro contact printing as standard procedures for making patterned S-layer lattices.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 16, 2018
- Accession Number
- AD1063082
Entities
People
- Dietmar Pum