Pseudomonas aeruginosa signaling systems and adaptation

Abstract

Pseudomonas aeruginosa genome contains a high proportion of regulatory genes, reflecting the ability of this proteobacterium to adapt to several environmental conditions. P. aeruginosa is often found in water, soil or associated with plants and animais and its versatility is conferred by the use of several nutrient sources, by the competitive advantage upon other microorganisms due to the production of secondary metabolism products, by its intrinsinc resistance to antibiotics, by the ability to communicate using chemical messages in a process known as quorum sensing and to grow as biofilms in biotic and abiotic surfaces. P. aeruginosa can behave as an opportunistic pathogen, colonizing burns, surgical wounds and causing pneumonia in cystic fibrosis and ventilation-assisted patients. These infections are difficult to erradicate due to P. aeruginosa large arsenal of virulence factors and antibiotic resistance. For the bacteria to sense and respond to environmental stimuli, signaling and effector systems must be finely tuned to assure their thriving in changing conditions. Despite the large body of knowledge regarding P. aeruginosa virulence and adaptation, many signaling transduction pathways are yet to be characterized and understood. Hence, the aim of this proposal is to study P. aeruginosa novel regulatory systems, such as proteins related to c-di-GMP signaling, ECF sigma factors and virulence-associated response regulators. Genetic, biochemical and transcriptomics approaches will be used to achieve the specific goals. (AU)