Adhesion of Pseudomonas aeruginosa to Conditioning Films

摘要

The formation of conditioning films can alter surface properties of the substratum. As a result, bacterial initial adhesion to inert surfaces in the aquatic environment is highly influenced by the surface properties of the substratum. It is known that the extracellular polymeric substances (EPS) are deeply involved in the bacterial adhesion. In this study, the impact of EPS conditioning films (i.e., alginate, bovine serum albumin (BSA), and original Pseudomonas aeruginosa EPS) on Pseudomonas aeruginosa PA01 bacterial adhesion was systematically investigated under four different ionic strength conditions Alginate and BSA were selected to represent polysaccharides and proteins of biofilm EPS, respectively. The physico-chemical properties (e.g. contact angle and zeta potential) of the bacterial cell and variously modified glass slides with EPS components were determined. These results showed that all EPS coatings enhanced bacterial adhesions under low ionic strength conditions, compared to surfaces with no EPS coating. However, bacterial adhesion on BSA and original P. aeruginosa EPS coated surfaces were hindered at high ionic strength conditions. This study implies that the protein component of EPS plays a central role in influencing bacterial initial adhesion, and that the impact of conditioning films on bacterial initial adhesion varies with ionic strength conditions.