Quorum Sensing and Biofilms in Entrobacteriaceae

Several bacterial species participate in two confirmable behaviours. Irreversible attachment to the surface (biofilm) and to regulate certain phenotypes expression which will synchronize their behaviour (quorum sensing). This sophisticated intercellular communication mechanism called quorum sensing (QS). QS play a major role in the formation of the biofilm & biofilm helps the bacteria in adhesion/ cohesion potentiality, metabolite interchange, cellular connection, defence, nutritious and resistance to medication. Since biofilm is resistant to antibiotics so targeting biofilm is the main therapeutic approach. Biofilm formation is one of the major reason of catheter associated urinary tract infections (CAUTI). E. coli and K. pneumoniae cause Urinary Tract Infection which cost about $1.6 billion in medical expenses every year. Both of them have ability to form biofilms. Exopolysaccharide matrix of biofilm is a double barrier for antibiotics and other antimicrobial substances, therefore makes bacteria more resistant. In many species QS mediated biofilm formation is present, targeting the QS system (anti-QS) are attracting attention in the drug development field. Another treatment strategy is using of bacteriophages. So the aim of our research was to find out bacterial strains able to form biofilms and check the activity of phages able to inhibit formation or eradication of biofilms. We used two species of strains, E. coli and four K. pneumoniae, out of which only E. coli #5 formed biofilm. Bacteriophage specific for E. coli#5 showed that this phage was able to impede the growth of biofilm and also help to eliminate already formed biofilm.