Catheter-Associated Urinary Tract Infection by Pseudomonas aeruginosa Is Mediated by Exopolysaccharide-Independent Biofilms

Cole, Stephanie; Records, Angela R.; Orr, Mona W.; Linden, Sara B.; Lee, Vincent T.

doi:10.1128/iai.01652-14

Cited by 150 publications

(138 citation statements)

References 51 publications

Supporting

Mentioning

135

Contrasting

Order By: Relevance

“…Second, the ⌬fliC strain was able to cause CAUTI similarly to PA14. Since mutations in the exopolysaccharides (29), flagella, and type IV pili are not required for P. aeruginosa to cause CAUTI, the c-di-GMP-regulated process that contributes to CAUTI is likely through an unknown mechanism that is likely specific to the urinary tract. Furthermore, the moderate reduction in bacterial burden for any of the single mutants with mutations in genes encoding DGC and PDE suggests that there is functional redundancy of DGCs in the urinary tract.…”

Section: Discussionmentioning

confidence: 99%

“…Previous data indicated that P. aeruginosa formed biofilms during the murine model of CAUTI independently of the Pel and Psl exopolysaccharides (29). Here we tested whether the c-di-GMP signaling pathway, which also regulates P. aeruginosa biofilm formation in vitro, participates during CAUTI.…”

Section: C-di-gmp Levels During Initial Infection Affect Colonizationmentioning

confidence: 92%

“…The P. aeruginosa-mediated CAUTI model was as described previously (28,29). Briefly, female CF-1 mice were anesthetized and catheterized with a 0.5-cm piece of polyethylene catheter tubing in the bladder.…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Cyclic Di-GMP Signaling Contributes to Pseudomonas aeruginosa-Mediated Catheter-Associated Urinary Tract Infection

Cole

Lee

2016

J Bacteriol

Self Cite

View full text Add to dashboard Cite

Bis-(3=-5=) cyclic dimeric GMP (c-di-GMP) controls the lifestyle transition between the sessile and motile states in many Gramnegative bacteria, including the opportunistic human pathogen Pseudomonas aeruginosa. Under laboratory conditions, high concentrations of c-di-GMP decrease motility and promote biofilm formation, while low concentrations of c-di-GMP promote motility and decease biofilm formation. Here we sought to determine the contribution of c-di-GMP signaling to biofilm formation during P. aeruginosa-mediated catheter-associated urinary tract infection (CAUTI). Using a murine CAUTI model, a decrease in CFU was detected in the bladders and kidneys of mice infected with strains overexpressing the phosphodiesterases (PDEs) encoded by PA3947 and PA2133 compared to those infected with wild-type P. aeruginosa. Conversely, overexpression of the diguanylate cyclases (DGCs) encoded by PA3702 and PA1107 increased the number of bacteria in bladder and significantly increased dissemination of bacteria to the kidneys compared to wild-type infection. To determine which of the DGCs and PDEs contribute to c-di-GMP signaling during infection, a panel of PA14 in-frame deletion mutants lacking DGCs and PDEs were tested in the CAUTI model. Results from these infections revealed five mutants, three containing GGDEF domains (⌬PA14_26970, ⌬PA14_72420, and ⌬siaD) and two containing dual GGDEF-EAL domains (⌬morA and ⌬PA14_07500), with decreased colonization of the bladder and dissemination to the kidneys. These results indicate that c-di-GMP signaling influences P. aeruginosa-mediated biofilms during CAUTI. IMPORTANCE Biofilm-based infections are an important cause of nosocomial infections, since they resist the immune response and traditional antibiotic treatment. Cyclic di-GMP (c-di-GMP) is a second messenger that promotes biofilm formation in many Gram-negative pathogens, including Pseudomonas aeruginosa.Here we determined the contribution of c-di-GMP signaling to catheter-associated urinary tract infection (CAUTI), an animal model of biofilm-based infection. P. aeruginosa with elevated levels of c-di-GMP during the initial infection produces an increased bacterial burden in the bladder and kidneys. Conversely, low concentrations of c-di-GMP decreased the bacterial burden in the bladder and kidneys. We screened a library of mutants with mutations in genes regulating c-di-GMP signaling and found several mutants that altered colonization of the urinary tract. This study implicates c-di-GMP signaling during CAUTI. P seudomonas aeruginosa is an opportunistic human pathogen that is a leading cause of nosocomial infections, including catheter-associated urinary tract infection (CAUTI), central lineassociated bloodstream infection (CLABSI), ventilator-associated pneumonia (VAP), and surgical site infection (SSI) (1). In CAUTI, dissemination of bacteria from the catheter can lead to pyelonephritis and bacteremia. The common theme for these infections is the ability of P. aeruginosa to form biofilms on the surfaces of medica...

show abstract

Section: Discussionmentioning

confidence: 99%

Section: C-di-gmp Levels During Initial Infection Affect Colonizationmentioning

confidence: 92%

See 1 more Smart Citation

Cyclic Di-GMP Signaling Contributes to Pseudomonas aeruginosa-Mediated Catheter-Associated Urinary Tract Infection

Cole

Lee

2016

J Bacteriol

Self Cite

View full text Add to dashboard Cite

show abstract

“…The number of cells per sample were enumerated at OD 600 = 0.6 and 2.0 for each strain by plating serial dilutions. The volume of one bacterium was estimated to be 4.3 × 10 −1 fL, assuming the bacterium to be cylindrical in shape with spherical poles having an average length of 1.5 and 0.65 μm in diameter based on SEM image analysis (80). The total c-di-GMP and pGpG extracted in each sample were3 then divided by the total intracellular volume of the cells in the sample to provide the intracellular concentration of each analyte.…”

Section: Methodsmentioning

confidence: 99%

Oligoribonuclease is the primary degradative enzyme for pGpG in Pseudomonas aeruginosa that is required for cyclic-di-GMP turnover

Orr

Donaldson

Severin

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

121

142

View full text Add to dashboard Cite

The bacterial second messenger cyclic di-GMP (c-di-GMP) controls biofilm formation and other phenotypes relevant to pathogenesis. Cyclic-di-GMP is synthesized by diguanylate cyclases (DGCs). Phosphodiesterases (PDE-As) end signaling by linearizing c-di-GMP to 5ʹ-phosphoguanylyl-(3ʹ,5ʹ)-guanosine (pGpG), which is then hydrolyzed to two GMP molecules by yet unidentified enzymes termed PDE-Bs. We show that pGpG inhibits a PDE-A from Pseudomonas aeruginosa. In a dual DGC and PDE-A reaction, excess pGpG extends the half-life of c-di-GMP, indicating that removal of pGpG is critical for c-di-GMP homeostasis. Thus, we sought to identify the PDE-B enzyme(s) responsible for pGpG degradation. A differential radial capillary action of ligand assay-based screen for pGpG binding proteins identified oligoribonuclease (Orn), an exoribonuclease that hydrolyzes two-to five-nucleotide-long RNAs. Purified Orn rapidly converts pGpG into GMP. To determine whether Orn is the primary enzyme responsible for degrading pGpG, we assayed cell lysates of WT and Δorn strains of P. aeruginosa PA14 for pGpG stability. The lysates from Δorn showed 25-fold decrease in pGpG hydrolysis. Complementation with WT, but not active site mutants, restored hydrolysis. Accumulation of pGpG in the Δorn strain could inhibit PDE-As, increasing c-di-GMP concentration. In support, we observed increased transcription from the c-di-GMP-regulated pel promoter. Additionally, the c-di-GMP-governed auto-aggregation and biofilm phenotypes were elevated in the Δorn strain in a pel-dependent manner. Finally, we directly detect elevated pGpG and c-di-GMP in the Δorn strain. Thus, we identified that Orn serves as the primary PDE-B enzyme that removes pGpG, which is necessary to complete the final step in the c-di-GMP degradation pathway.cyclic di-GMP | oligoribonuclease | pGpG | PDE-B | nanoRNase

show abstract

“…In addition, the group of surface proteins called MSCRAMMs (microbial surface components recognizing adhesive matrix molecules) is also major determinants of the initial bacterial attachment on tissues and biomaterials. P. aeruginosa produces three different exopolysaccharides (alginate, Psl and Pel) that participates in biofilm formation [58]. Alginates are composed of uronic acid and reduce the biofilm susceptibility to antibiotic and human defense [59].…”

Section: Bacterial Biofilm Productionmentioning

confidence: 99%

Biofilm: An Important Bacterial Feature Still to Deal With

Novais

Abreu

Castro

2016

Journal of Life Sciences Research

View full text Add to dashboard Cite

Currently, the bacterial infections are one of the main causes of death worldwide and a public health problem for most governments. In this scenario, virulence factors are of importance, including the capacity of forming biofilm. The ability of producing biofilms is directly involved in bacterial pathogenicity and hugely worse the risk of death due to a bacterial infection. This feature allows the bacteria to colonize different surfaces (e.g. Medical devices), and causes several complications, especially in nosocomial infections. This work reviewed biolfim producing mechanisms, the relation with resistance process and the problems associated to biofilms-affected-medical devices.

show abstract

Catheter-Associated Urinary Tract Infection by Pseudomonas aeruginosa Is Mediated by Exopolysaccharide-Independent Biofilms

Cited by 150 publications

References 51 publications

Cyclic Di-GMP Signaling Contributes to Pseudomonas aeruginosa-Mediated Catheter-Associated Urinary Tract Infection

Cyclic Di-GMP Signaling Contributes to Pseudomonas aeruginosa-Mediated Catheter-Associated Urinary Tract Infection

Oligoribonuclease is the primary degradative enzyme for pGpG in Pseudomonas aeruginosa that is required for cyclic-di-GMP turnover

Biofilm: An Important Bacterial Feature Still to Deal With

Contact Info

Product

Resources

About