The influence of nutrient culture media on Escherichia coli adhesion and biofilm formation ability

摘要

Adhesion of Escherichia coli strains to inert and cellular substrates and formation of biofilmsare complex processes that are influenced by many factors. This work highlighted the variation ofbacterial adhesion in different culture conditions in E. coli strains isolated from different infectionssites. The experimental infection of THP-1 and HeLa cells showed that the degree of adhesion, theadhesion pattern and the virulence ability of the tested strains are influenced by the composition of theused medium. A nutrients rich medium increases the level of adhesion and strains ability to produceslime. In addition, the ability to form biofilms is biased by the nutrient media: in minimal medium theproduction of biofilms is very low, almost non-existent, but in a rich nutrient medium ability of bacteriato produce biofilms increases exponentially. Changes of the culture medium composition lead to majordifferences in the degree of adhesion and hence the degree of formation of biofilms. Lack ofstandardized methods contributes to different results regarding the contribution of different metabolicand virulence features on the ability of adhesion and biofilm formation, and on the progress of thewhole infectious process.