Structure‐Function Relationships of Rhamnolipid and Exopolysacharide Biosurfactants of Pseudomonas aeruginosa as Therapeutic Targets in Cystic Fibrosis Lung Infections

Abstract

Chronic Pseudomonas aeruginosa lung infection is the cause of much morbidity and most of the mortality in cystic fibrosis (CF) patients. The high prevalence of P. aeruginosa infections in CF is related to the microbe's large genome and mechanisms of adaptation to the CF lung environment, the host immune system and antibiotic resistance. Among a wide range of P. aeruginosa metabolites involved in infection development in CF, the biosurfactant compounds, rhamnolipids (RLs) and exopolysaccharides (EPSs), have important roles in the early stages of P. aeruginosa infection in CF. RLs and EPSs are involved in bacterial adhesion, biofilm formation, antibiotic resistance, and impairment of host immune system pathways, as well as in processes such as biofilm maintenance and the mucoid phenotype of P. aeruginosa, which lead to development of chronic infection. Due to the proposed roles of RLs and EPSs and the importance of prevention and treatment of P. aeruginosa respiratory infections in CF, these compounds are promising targets for patient therapy. In the future, impairment of P. aeruginosa quorum sensing (QS) pathways and modification of host respiratory mucus epithelial membranes should be considered as potential approaches in preventing respiratory infections caused by this microbe in CF patients.