Interplay Of Flow Conditions, Cell Properties And Surface Structures In Attachment Of Bacterial Cells

Attachment of bacteria in natural conditions enable them a sustainable development, resulting in biofilm formation. Staying within biofilms, bacteria areprotected from colonization by other microbes, and they form mutualistic communities that allow to trade off inevitable compounds. The presence of thebiofilms is also a key process in biotechnological setups since microbes are protected from abiotic conditions (e.g. temperature, flushing, product separation),which enables a long term processing without continuous replacement of biomass. However, not all bacteria tend to attach very well and form biofilms sincethey lack surface receptors, do not produce extracellular matrices or do not have other appendages (e.g. pili, flagella) that facilitate the attachment. Therefore,we propose an alternative solution by micro-structuring the surface with different sizes of holes, which would enable cells to attach. Accordingly, we aimed todetermine interplay between (i) topography, (ii) fluid flow as well as salt concentration and (iii) the cell geometry and cell wall structure to the process ofattachmentt of cells. Our results showed that the structured surfaces with the depth, close to the size of bacteria are the most suitable to induce cellularattachment. We observed that specific features as biofilm formation or cell wall structure significantly differentiate the cells in the ability to colonize the surface.Since we tested attachment under flow conditions, the amount of deposited cells was dependent on the particular conditions of flow, while salinity of mediasignificantly improved the attachment.