Effects Of Exopolysaccharide Hydrolase On Movement Characteristics And The Biofilm Of Pseudomonas Aeruginosa

Pseudomonas aeruginosa is one of the most common pathogens causing nosocomial infections.Pseudomonas aeruginosa colonized the lungs causing chronic inflammation,progressive loss of lung function,and eventually respiratory failure or even death.Bacteria in biofilms show increased antibiotic resistance and strong anti-immune system clearance compared to plankton.The hallmark of biofilm formation is that they are surrounded by an extracellular matrix that can consist of a mixture of DNA,fatty acids,proteins and polysaccharides.Extracellular polysaccharides are the main components of EPS.Pseudomonas aeruginosa produces at least three different extracellular polysaccharides: alginate,Pel and Psl,which determine the stability of the biofilm structure.We used high-throughput bacterial tracking technique in combination with flow cell to verify the specific role of PslG and PelA.PslG is a peripherin protein in the Psl synthesis pathway.PslG has a significant effect on the bacteria movement at single-cell level.After adding PslG bacterial movement was significantly accelerated,bacteria moved significantly faster on the surface by 4-5 times,and in a more random way with no clear preferred direction;the trajectory was rough and the efficiency of surface coverage increased;it took bacteria roughly two times longer to form microcolonies with PslG addition than without.We also observed that PelA has a certain effect on Pseudomonas aeruginosa surface movement,as well as in the formation of biofilm.In the meantime,in order to see better degradation effect,PslG and PelA were added to the microcolonies,then the bacteria detached from microcolonies.