Papel biológico de genes ubicados en una isla genómica en Pseudomonas aeruginosa

Pseudomonas aeruginosa is an omnipresent Gram negative opportunistic human pathogen that is not considered part of the human commensal intestinal microbiota. However, depletion of the intestinal microbiota (dysbiosis) after antibiotic treatment facilitates colonization of the intestinal tract by multiple drug P. aeruginosa resistant. A possible alternative to conventional treatments is based on the use of functional foods with prebiotic activity. The bifidogenic effect of fructooligosaccharides (FOS) is well established; it has been shown to promote the growth of specific beneficial intestinal bacteria such as bifidobacteria. Previous studies of the nosocomial opportunistic pathogen Pseudomonas aeruginosa PAO1 have shown that FOS reduce the growth and formation of biofilms, due to a decrease in motility and exotoxin secretion. However, the transcriptional basis of these phenotypic alterations remains unclear. To address this question, an RNA sequence analysis (RNAseq) was performed that allowed us to detect the presence of a genomic island formed by 15 genes which are repressed in the presence of FOS. Previously, it was demonstrated by the functional analysis of isogenic mutants, that the genes PA0643, PA0644 and PA0646, located in this genomic island, encode proteins involved in growth, biofilm formation, motility. In this context, this work reflected the implication of these genes in the modulation of the inflammatory response.