Virulence of the Pseudomonas fluorescens clinical strain MFN1032 towards Dictyostelium discoideumand macrophages in relation with type III secretion system

Spérandio, Daniel; Decoin, Victorien; Latour, Xavier; Mijouin, Lily; Hillion, Mélanie; Feuilloley, Marc; Orange, Nicole; Merieau, Annabelle

doi:10.1186/1471-2180-12-223

Cited by 13 publications

(14 citation statements)

References 42 publications

(52 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As of the end of 2013, there were 16 fully sequenced strains from the P. fluorescens species complex, and all but one originated from plant surfaces, roots, or the surrounding soil (Table 4). P. fluorescens can also be found in an antagonistic relationship with eukaryotic microbes, including oomycetes and amoeba (35,36,48,51,59,(63)(64)(65), with the latter relationship potentially reflecting conserved mechanisms that are also used with macrophages, as has been hypothesized for other bacteria (66).…”

Section: Phenotypic Traits and Cultivation Of P Fluorescensmentioning

confidence: 99%

“…Environmental isolates of P. fluorescens have an optimal temperature growth range of 25 to 30°C and are not virulent to human cells, but certain strains of P. fluorescens isolated from clinical samples have a higher permissive growth range, up to 37°C, and show increased virulence against human cells (53,(57)(58)(59). Two P. fluorescens strains, MFY162 and MFN1032, can adhere to human glial cells in culture, and MFN1032 can induce apoptosis.…”

Section: Interaction Of P Fluorescens With Human Cellsmentioning

confidence: 99%

“…3). Isolates of P. fluorescens derived from nonmammalian samples have a permissive growth range of 4 to 32°C (62), while isolates from humans and other mammals have an elevated upper range extending to 37°C (53,(57)(58)(59). As of the end of 2013, there were 16 fully sequenced strains from the P. fluorescens species complex, and all but one originated from plant surfaces, roots, or the surrounding soil (Table 4).…”

Section: Phenotypic Traits and Cultivation Of P Fluorescensmentioning

confidence: 99%

“…P. fluorescens has been studied most widely as an environmental microbe, most notably for its role in promoting plant health via a number of encoded antimicrobial mechanisms (25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38). However, P. fluorescens also possesses a number of functional traits that provide it with the capability to grow and thrive in mammalian hosts, including production of bioactive secondary metabolites (26-30, 33, 39-42), siderophores (43)(44)(45), and a type III secretion system (46)(47)(48)(49)(50)(51), the ability to form biofilms (20,(52)(53)(54)(55)(56), and the plasticity of some strains to adapt to growth at higher temperature (53,(57)(58)(59).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Microbiology, Genomics, and Clinical Significance of the Pseudomonas fluorescens Species Complex, an Unappreciated Colonizer of Humans

et al. 2014

View full text Add to dashboard Cite

SUMMARY Pseudomonas fluorescens is not generally considered a bacterial pathogen in humans; however, multiple culture-based and culture-independent studies have identified it at low levels in the indigenous microbiota of various body sites. With recent advances in comparative genomics, many isolates originally identified as the “species” P. fluorescens are now being reclassified as novel Pseudomonas species within the P. fluorescens “species complex.” Although most widely studied for its role in the soil and the rhizosphere, P. fluorescens possesses a number of functional traits that provide it with the capability to grow and thrive in mammalian hosts. While significantly less virulent than P. aeruginosa , P. fluorescens can cause bacteremia in humans, with most reported cases being attributable either to transfusion of contaminated blood products or to use of contaminated equipment associated with intravenous infusions. Although not suspected of being an etiologic agent of pulmonary disease, there are a number of reports identifying it in respiratory samples. There is also an intriguing association between P. fluorescens and human disease, in that approximately 50% of Crohn's disease patients develop serum antibodies to P. fluorescens . Altogether, these reports are beginning to highlight a far more common, intriguing, and potentially complex association between humans and P. fluorescens during health and disease.

show abstract

Section: Phenotypic Traits and Cultivation Of P Fluorescensmentioning

confidence: 99%

Section: Interaction Of P Fluorescens With Human Cellsmentioning

confidence: 99%

Section: Phenotypic Traits and Cultivation Of P Fluorescensmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Microbiology, Genomics, and Clinical Significance of the Pseudomonas fluorescens Species Complex, an Unappreciated Colonizer of Humans

et al. 2014

View full text Add to dashboard Cite

show abstract

“…If the bacteria are virulent to D. discoideum, they cause amoeba growth inhibition and/or death, which can be observed by a decrease in the number of lysis plaques. In pathogenic P. aeruginosa and P. fluorescens isolates, D. discoideum growth inhibition is the result of a T3SS and/or biosurfactant contact (60,61). This test was performed as described by Carilla-Latorre et al (96) (62).…”

Section: Methodsmentioning

confidence: 99%

Type III Secretion System and Virulence Markers Highlight Similarities and Differences between Human- and Plant-Associated Pseudomonads Related to Pseudomonas fluorescens and P. putida

Mazurier

Merieau

Bergeau

et al. 2015

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

dPseudomonas fluorescens is commonly considered a saprophytic rhizobacterium devoid of pathogenic potential. Nevertheless, the recurrent isolation of strains from clinical human cases could indicate the emergence of novel strains originating from the rhizosphere reservoir, which could be particularly resistant to the immune system and clinical treatment. The importance of type three secretion systems (T3SSs) in the related Pseudomonas aeruginosa nosocomial species and the occurrence of this secretion system in plant-associated P. fluorescens raise the question of whether clinical isolates may also harbor T3SSs. In this study, isolates associated with clinical infections and identified in hospitals as belonging to P. fluorescens were compared with fluorescent pseudomonads harboring T3SSs isolated from plants. Bacterial isolates were tested for (i) their genetic relationships based on their 16S rRNA phylogeny, (ii) the presence of T3SS genes by PCR, and (iii) their infectious potential on animals and plants under environmental or physiological temperature conditions. Two groups of bacteria were delineated among the clinical isolates. The first group encompassed thermotolerant (41°C) isolates from patients suffering from blood infections; these isolates were finally found to not belong to P. fluorescens but were closely related and harbored highly conserved T3SS genes belonging to the Ysc-T3SS family, like the T3SSs from P. aeruginosa. The second group encompassed isolates from patients suffering from cystic fibrosis; these isolates belonged to P. fluorescens and harbored T3SS genes belonging to the Hrp1-T3SS family found commonly in plant-associated P. fluorescens. The group of fluorescent pseudomonads is composed of ubiquitous bacteria commonly encountered in aquatic, aerial, and soil environments (1, 2). Under iron limitation, members of this group share the ability to produce soluble greenish fluorescent siderophores that appear fluorescent under UV illumination (3). These bacteria display a broad potential for adaptation to fluctuating environmental conditions, such as temperature variations, thanks to their highly versatile metabolism and the plasticity of their large genome (4-6). Some species in this group, such as Pseudomonas fluorescens, are commonly associated with plants as saprotrophs, especially in the rhizosphere since their densities and activities are greater than in the surrounding soil (6-9). Some of these populations may have beneficial effects on plant growth and health (10). In contrast, other fluorescent Pseudomonas species are pathogens of humans, animals, and plants, i.e., eukaryotic hosts (11, 12).The type three secretion systems (T3SSs) have been shown to play a determining role in the pathogenicity produced by fluorescent pseudomonads such as P. aeruginosa and P. syringae, pathogens of humans and plants, respectively (11). In these two pathogenic species, T3SS is involved in cell-to-cell contact with the eukaryotic host and in bacterial virulence. Genes encoding the basic structure of th...

show abstract

Assessing Pseudomonas aeruginosa Virulence Using a Nonmammalian Host: Dictyostelium discoideum

Filion

Charette

2014

Methods in Molecular Biology

View full text Add to dashboard Cite

Dictyostelium discoideum, a soil amoeba, can be used as an alternative host to study the virulence of various bacterial species, including Pseudomonas aeruginosa. A simple quantitative test based on the ability of D. discoideum to grow on a bacterial lawn has been developed using this amoeba to assay the virulence of P. aeruginosa strains. The assay needs to be customized for the strains to be tested in order to be able to discriminate between virulent and avirulent P. aeruginosa strains. These steps are described in this protocol.

show abstract

Virulence of the Pseudomonas fluorescens clinical strain MFN1032 towards Dictyostelium discoideumand macrophages in relation with type III secretion system

Cited by 13 publications

References 42 publications

Microbiology, Genomics, and Clinical Significance of the Pseudomonas fluorescens Species Complex, an Unappreciated Colonizer of Humans

Microbiology, Genomics, and Clinical Significance of the Pseudomonas fluorescens Species Complex, an Unappreciated Colonizer of Humans

Type III Secretion System and Virulence Markers Highlight Similarities and Differences between Human- and Plant-Associated Pseudomonads Related to Pseudomonas fluorescens and P. putida

Assessing Pseudomonas aeruginosa Virulence Using a Nonmammalian Host: Dictyostelium discoideum

Contact Info

Product

Resources

About