BACKGROUND AND PURPOSE: Pseudomonas aeruginosa has been reported to monitor its cell density as well as expression of virulence determinants by quorum-sensing signal mechanisms operative through autoinducers. In the present investigation, we studied the contribution of quorum-sensing signals during the course of P. aeruginosa-induced pyelonephritis in mice. METHODS: The standard parent strain of P. aeruginosa (PAO1), possessing functional las and rhl quorum-sensing systems and its isogenic mutant strains, PAO-JP1 (single mutant), harboring a mutated lasI gene and PAO-JP3 (double mutant), harboring mutated lasI and rhlR genes were employed. One uroisolate of P. aeruginosa belonging to serotype O8 and deficient in production of quorum-sensing signals was also used. RESULTS: The parent strain of P. aeruginosa was significantly more virulent compared to its isogenic mutant strains and quorum-sensing negative clinical strain, as assessed by neutrophil influx, malondialdehyde production, renal bacterial load and pathology induced in experimental animals. CONCLUSIONS: Quorum-sensing systems play an important role in the pathogenicity of P. aeruginosa in pyelonephritis. Both the las and rhl quorum-sensing systems are important for the virulence of P. aeruginosa in the development of pyelonephritis.
BACKGROUND AND PURPOSE:Pseudomonas aeruginosa has been reported to monitor its cell density as well as expression of virulence determinants by quorum-sensing signal mechanisms operative through autoinducers. In the present investigation, we studied the contribution of quorum-sensing signals during the course of P. aeruginosa-induced pyelonephritis in mice. METHODS: The standard parent strain of P. aeruginosa (PAO1), possessing functional las and rhl quorum-sensing systems and its isogenic mutant strains, PAO-JP1 (single mutant), harboring a mutated lasI gene and PAO-JP3 (double mutant), harboring mutated lasI and rhlR genes were employed. One uroisolate of P. aeruginosa belonging to serotype O8 and deficient in production of quorum-sensing signals was also used. RESULTS: The parent strain of P. aeruginosa was significantly more virulent compared to its isogenic mutant strains and quorum-sensing negative clinical strain, as assessed by neutrophil influx, malondialdehyde production, renal bacterial load and pathology induced in experimental animals. CONCLUSIONS: Quorum-sensing systems play an important role in the pathogenicity of P. aeruginosa in pyelonephritis. Both the las and rhl quorum-sensing systems are important for the virulence of P. aeruginosa in the development of pyelonephritis.
Authors: G Singh; B Wu; M S Baek; A Camargo; A Nguyen; N A Slusher; R Srinivasan; J P Wiener-Kronish; S V Lynch Journal: Microb Pathog Date: 2010-06-02 Impact factor: 3.738
Authors: James J Lazenby; Phoebe E Griffin; Jennelle Kyd; Cynthia B Whitchurch; Margaret A Cooley Journal: PLoS One Date: 2013-04-10 Impact factor: 3.240
Authors: Braj R Singh; Brahma N Singh; Akanksha Singh; Wasi Khan; Alim H Naqvi; Harikesh B Singh Journal: Sci Rep Date: 2015-09-08 Impact factor: 4.379