Role of the Quorum Sensing Mechanism in the Response of <i>Pseudomonas aeruginosa</i> to Lethal and Sublethal UVA Irradiation

Costa, Carolina Ortiz Rocha da; Pezzoni, Magdalena; Fernández, Rubén O.; Pizarro, Ramón A.

doi:10.1111/j.1751-1097.2010.00800.x

Cited by 17 publications

(13 citation statements)

References 58 publications

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“…A key difference between these two types of antioxidant enzymes is that peroxiredoxin is 100-to 1000-fold less efficient than catalase; the latter becomes crucial once the former is saturated with hydrogen peroxide (Parsonage et al, 2008). Further, there is evidence that catalase is critical in minimizing ultraviolet-induced oxidative damage in bacteria (Costa et al, 2010). Phylogenetic analysis suggested that this gene was acquired through horizontal gene transfer (Figure 2b), which is further substantiated by its absence in the genomes of any of the seven cultured marine Thaumarchaeota sequenced to date by homology search, all of which are members of the epipelagic ecotype (Supplementary Figure S2).…”

Section: Diversification Of Marine Thaumarchaeota H Luo Et Almentioning

confidence: 99%

Single-cell genomics shedding light on marine Thaumarchaeota diversification

et al. 2013

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Previous studies based on analysis of amoA, 16S ribosomal RNA or accA gene sequences have established that marine Thaumarchaeota fall into two phylogenetically distinct groups corresponding to shallow-and deep-water clades, but it is not clear how water depth interacts with other environmental factors, including light, temperature and location, to affect this pattern of diversification. Earlier studies focused on single-gene distributions were not able to link phylogenetic structure to other aspects of functional adaptation. Here, we analyzed the genome content of 46 uncultivated single Thaumarchaeota cells sampled from epi-and mesopelagic waters of subtropical, temperate and polar oceans. Phylogenomic analysis showed that populations diverged by depth, as expected, and that mesopelagic populations from different locations were well mixed. Functional analysis showed that some traits, including putative DNA photolyase and catalase genes that may be related to adaptive mechanisms to reduce light-induced damage, were found exclusively in members of the epipelagic clade. Our analysis of partial genomes has thus confirmed the depth differentiation of Thaumarchaeota populations observed previously, consistent with the distribution of putative mechanisms to reduce light-induced damage in shallow-and deep-water populations.

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Section: Diversification Of Marine Thaumarchaeota H Luo Et Almentioning

confidence: 99%

Single-cell genomics shedding light on marine Thaumarchaeota diversification

et al. 2013

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“…This difference between DR and EC in antioxidant production was clearly visible ( Fig 4A ) and supported by linear regression analysis ( Fig 4B ). Fourth, antioxidant enzymes can be induced in a cell-concentration-dependent manner through quorum sensing [ 28 , 29 ].…”

Section: Discussionmentioning

confidence: 99%

Microbial cells can cooperate to resist high-level chronic ionizing radiation

et al. 2017

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Understanding chronic ionizing radiation (CIR) effects is of utmost importance to protecting human health and the environment. Diverse bacteria and fungi inhabiting extremely radioactive waste and disaster sites (e.g. Hanford, Chernobyl, Fukushima) represent new targets of CIR research. We show that many microorganisms can grow under intense gamma-CIR dose rates of 13–126 Gy/h, with fungi identified as a particularly CIR-resistant group of eukaryotes: among 145 phylogenetically diverse strains tested, 78 grew under 36 Gy/h. Importantly, we demonstrate that CIR resistance can depend on cell concentration and that certain resistant microbial cells protect their neighbors (not only conspecifics, but even radiosensitive species from a different phylum), from high-level CIR. We apply a mechanistically-motivated mathematical model of CIR effects, based on accumulation/removal kinetics of reactive oxygen species (ROS) and antioxidants, in bacteria (3 Escherichia coli strains and Deinococcus radiodurans) and in fungi (Candida parapsilosis, Kazachstania exigua, Pichia kudriavzevii, Rhodotorula lysinophila, Saccharomyces cerevisiae, and Trichosporon mucoides). We also show that correlations between responses to CIR and acute ionizing radiation (AIR) among studied microorganisms are weak. For example, in D. radiodurans, the best molecular correlate for CIR resistance is the antioxidant enzyme catalase, which is dispensable for AIR resistance; and numerous CIR-resistant fungi are not AIR-resistant. Our experimental findings and quantitative modeling thus demonstrate the importance of investigating CIR responses directly, rather than extrapolating from AIR. Protection of radiosensitive cell-types by radioresistant ones under high-level CIR is a potentially important new tool for bioremediation of radioactive sites and development of CIR-resistant microbiota as radioprotectors.

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“…2002). The link between PL or UV treatments and QS networks has soon been reported, because it has been shown that the RhlI/RhlR system is fundamental in the defence against the toxic effects of UVs (Costa et al. 2011).…”

Section: Discussionmentioning

confidence: 99%

Adaptation of Pseudomonas aeruginosa to a pulsed light-induced stress

Massier

Rincé

Maillot

et al. 2012

Journal of Applied Microbiology

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Aims: Pulsed light (PL) technology is an efficient surface decontamination process. Used in low transmitted energy conditions, PL induces a stress that can be perceived by bacteria. The effect of such a PL stress was investigated on the highly environmental adaptable germ Pseudomonas aeruginosa PAO1. Methods and Results: Pulses of transmitted energy (fluence) reaching 1AE8 J cm )2 can kill 10 9 bacteria. Application of a lower sublethal PL dose allowed the bacteria to resist and survive more efficiently to a subsequent dose of PL. This sublethal dose was not increasing the mutation frequency of Ps. aeruginosa, but altered the abundance of 15 proteins as revealed by a global proteome analysis, including stress-induced proteins, phage-related proteins, energy and carbon metabolisms, cell motility, and transcription and translation regulators. Conclusions: A response to a low-energy PL dose takes place in Ps. aeruginosa, reducing the energy conversion systems, while increasing transcription and translation processes to produce proteins involved in chaperone mechanisms and phage-related proteins, probably to protect the bacterium against a new PL-induced stress. Significance and Impact of the Study: Taken together, these results suggest that a low-energy PL dose is sufficient to provoke adaptation of Ps. aeruginosa, leading to enhancing its resistance to a subsequent lethal treatment.

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Role of the Quorum Sensing Mechanism in the Response of Pseudomonas aeruginosa to Lethal and Sublethal UVA Irradiation

Cited by 17 publications

References 58 publications

Single-cell genomics shedding light on marine Thaumarchaeota diversification

Single-cell genomics shedding light on marine Thaumarchaeota diversification

Microbial cells can cooperate to resist high-level chronic ionizing radiation

Adaptation of Pseudomonas aeruginosa to a pulsed light-induced stress

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