IN VITRO MONOSPECIES, MULTISPECIES AND NECROTROPHIC BIOFILM PRODUCTION OF Legionella pneumophila IN WATER SUPPLY SYSTEMS

Biofilms provide a shelter for microorganism to survive in unsuitable environments. Legionella pneumophila can produce monospecies biofilms in vitro, but usually exist in multispecies biofilms in nature. In this study, biofilm production capabilities of L. pneumophila strains isolated from water supply systems, the main resource of legionnaire's disease, was investigated. They were detect-ted to form biofilms in sterile tap water and BYE medium. In addition, it was shown that L. pneumophila had the ability of biofilm production using dead bacteria cells as food. Multispecies biofilm production and attachment to preformed biofilms were studied with six other bacterial species. L. pneumophila was found to have positive biofilm interactions for multispecies biofilm production with Klebsiella pneumoniae, Enterococcus faecalis, Pseudomonas putida and Pseudomonas flourescens, and for attachment to preformed biofilms with K pneumoniae, E. faecalis and P.aeruginosa. The results suggest that L. pneumophila could produce biofilms and join to biofilms of other bacteria, even in the conditions that it is not able to grow.