The Pseudomonas aeruginosa 4-Quinolone Signal Molecules HHQ and PQS Play Multifunctional Roles in Quorum Sensing and Iron Entrapment

Diggle, Stephen P.; Matthijs, Sandra; Wright, Victoria; Fletcher, Matthew P.; Chhabra, Siri Ram; Lamont, Iain L.; Kong, Xiaole; Hider, Robert C.; Cornélis, Pierre; Cámara, Miguel; Williams, Paul

doi:10.1016/j.chembiol.2006.11.014

Cited by 434 publications

(496 citation statements)

References 47 publications

Supporting

Mentioning

482

Contrasting

Unclassified

Order By: Relevance

“…PqsE is in an operon with pqsA-D, but is not involved in the synthesis of PQS. However, disruption of pqsE causes loss of signal transduction of several but not all of the processes believed to be regulated by the pqs system (Diggle et al, 2007b). The exact mechanism of action of this protein is still unknown.…”

Section: C M Antunes and Othersmentioning

confidence: 99%

Quorum sensing in bacterial virulence

et al. 2010

View full text Add to dashboard Cite

Bacteria communicate through the production of diffusible signal molecules termed autoinducers. The molecules are produced at basal levels and accumulate during growth. Once a critical concentration has been reached, autoinducers can activate or repress a number of target genes. Because the control of gene expression by autoinducers is cell-density-dependent, this phenomenon has been called quorum sensing. Quorum sensing controls virulence gene expression in numerous micro-organisms. In some cases, this phenomenon has proven relevant for bacterial virulence in vivo. In this article, we provide a few examples to illustrate how quorum sensing can act to control bacterial virulence in a multitude of ways. Several classes of autoinducers have been described to date and we present examples of how each of the major types of autoinducer can be involved in bacterial virulence. As quorum sensing controls virulence, it has been considered an attractive target for the development of new therapeutic strategies. We discuss some of the new strategies to combat bacterial virulence based on the inhibition of bacterial quorum sensing systems.

show abstract

Section: C M Antunes and Othersmentioning

confidence: 99%

Quorum sensing in bacterial virulence

et al. 2010

View full text Add to dashboard Cite

show abstract

“…The bacteria cell density was determined as described in the legend of Interspecies competition triggers virulence A Trejo-Hernández et al signaling pathway rather than the LasR/3-oxo-C12-HSL pathways. PQS has been demonstrated to induce the expression of genes associated with the iron-deprivation pathway, in which the iron-chelating activity of PQS induces pyoverdine production (Bredenbruch et al, 2006;Diggle et al, 2007).…”

Section: Interspecies Competition Triggers Virulencementioning

confidence: 99%

Interspecies competition triggers virulence and mutability in Candida albicans–Pseudomonas aeruginosa mixed biofilms

et al. 2014

View full text Add to dashboard Cite

Inter-kingdom and interspecies interactions are ubiquitous in nature and are important for the survival of species and ecological balance. The investigation of microbe-microbe interactions is essential for understanding the in vivo activities of commensal and pathogenic microorganisms. Candida albicans, a polymorphic fungus, and Pseudomonas aeruginosa, a Gram-negative bacterium, are two opportunistic pathogens that interact in various polymicrobial infections in humans. To determine how P. aeruginosa affects the physiology of C. albicans and vice versa, we compared the proteomes of each species in mixed biofilms versus single-species biofilms. In addition, extracellular proteins were analyzed. We observed that, in mixed biofilms, both species showed differential expression of virulence proteins, multidrug resistance-associated proteins, proteases and cell defense, stress and iron-regulated proteins. Furthermore, in mixed biofilms, both species displayed an increase in mutability compared with monospecific biofilms. This characteristic was correlated with the downregulation of enzymes conferring protection against DNA oxidation. In mixed biofilms, P. aeruginosa regulates its production of various molecules involved in quorum sensing and induces the production of virulence factors (pyoverdine, rhamnolipids and pyocyanin), which are major contributors to the ability of this bacterium to cause disease. Overall, our results indicate that interspecies competition between these opportunistic pathogens enhances the production of virulence factors and increases mutability and thus can alter the course of hostpathogen interactions in polymicrobial infections.

show abstract

“…When grown in LB medium, YE instead produced more pyoverdine than the wild-type strain PAO1. To the best of our knowledge, there are no reports regarding a direct correlation between the rhl QS system and pyoverdine production, which has been instead related to the las and the P. aeruginosa QS systems (Stintzi et al, 1998;Diggle et al, 2007). On the other hand, it is well known that the P. aeruginosa QS systems are interconnected (Lee & Zhang, 2015), and thus an influence of the rhl system on the production of this pigment cannot be ruled out.…”

Section: Discussionmentioning

confidence: 82%

Pigments influence the tolerance of Pseudomonas aeruginosa PAO1 to photodynamically induced oxidative stress

et al. 2015

View full text Add to dashboard Cite

Pseudomonas aeruginosa is an opportunistic pathogen known to be resistant to different classes of antibiotics and disinfectants. P. aeruginosa also displays a certain degree of tolerance to photodynamic therapy (PDT), an alternative antimicrobial approach exploiting a photo-oxidative stress induced by exogenous photosensitizers and visible light. To evaluate whether P. aeruginosa pigments can contribute to its relative tolerance to PDT, we analysed the response to this treatment of isogenic transposon mutants of P. aeruginosa PAO1 with altered pigmentation. In general, in the presence of pigments a higher tolerance to PDT-induced photooxidative stress was observed. Hyperproduction of pyomelanin makes the cells much more tolerant to stress caused by either radicals or singlet oxygen generated by different photosensitizers upon photoactivation. Phenazines, pyocyanin and phenazine-1-carboxylic acid, produced in different amounts depending on the cultural conditions, are able to counteract both types of PDT-elicited reactive oxygen species. Hyperproduction of pyoverdine, caused by a mutation in a quorum-sensing gene, rendered P. aeruginosa more tolerant to a photosensitizer that generates mainly singlet oxygen, although in this case the observed tolerance to photooxidative stress cannot be exclusively attributed to the presence of the pigment.

show abstract

The Pseudomonas aeruginosa 4-Quinolone Signal Molecules HHQ and PQS Play Multifunctional Roles in Quorum Sensing and Iron Entrapment

Cited by 434 publications

References 47 publications

Quorum sensing in bacterial virulence

Quorum sensing in bacterial virulence

Interspecies competition triggers virulence and mutability in Candida albicans–Pseudomonas aeruginosa mixed biofilms

Pigments influence the tolerance of Pseudomonas aeruginosa PAO1 to photodynamically induced oxidative stress

Contact Info

Product

Resources

About