Involvement of Nitrate Reductase and Pyoverdine in Competitiveness of
            <i>Pseudomonas fluorescens</i>
            Strain C7R12 in Soil

Mirleau, Pascal; Philippot, Laurent; Corberand, Thérèse; Lemanceau, Philippe

doi:10.1128/aem.67.6.2627-2635.2001

Cited by 48 publications

(35 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Mirleau et al (98) observed that nitrate reductase and pyoverdine defective mutants were significantly less competitive than the wild type strain in the rhizosphere or in the bulk soil. Delorme et al (33) suggested that Pseudomonads strains that had both genes for denitrification process (narG and nosZ) would better survive in the soil environment.…”

Section: Ecological Aspects Of Pseudomonads In the Rhizospherementioning

confidence: 99%

Fluorescent Pseudomonads associated with the rhizosphere of crops: an overview

Botelho

Mendonça-Hagler

2006

Braz. J. Microbiol.

View full text Add to dashboard Cite

Environmental concerns have led to the need of sustainable use of natural resources. The conventional agriculture caused considerable impacts on soils and waters. It is important to change certain agricultural managements to environmental cleaner techniques. The sustainable agriculture has pointed many approaches and techniques to reduce environmental impact. One of those strategies is the utilization of the soil microbiota to induce plant growth, control of plant diseases and biodegradation of xenobiotic compounds. Studies on the relationship between roots and microbiota are essential to achieve viable agricultural applications. These studies indicate that one of the most abundant microorganisms in the rhizosphere (area around the roots) is fluorescent Pseudomonas spp. They have been considered as an alternative to agrochemicals for controlling plant diseases and increasing plant development. This review addresses the main findings on fluorescent Pseudomonads. It summarizes and discusses significant aspects of this general topic, including (i) rhizosphere as a microhabitat; (ii) taxonomic, genetic and ecological aspects of fluorescent Pseudomonads in the rhizosphere; (iii) mechanisms of Plant Growth Promoting and Biological Control and (iv) commercial use of PGPR in agriculture.

show abstract

Section: Ecological Aspects Of Pseudomonads In the Rhizospherementioning

confidence: 99%

Fluorescent Pseudomonads associated with the rhizosphere of crops: an overview

Botelho

Mendonça-Hagler

2006

Braz. J. Microbiol.

View full text Add to dashboard Cite

show abstract

“…The type strains of the species P. aeruginosa, P. chlororaphis, P. fluorescens, and P. putida were included in addition to that of P. lini. Finally, two reference (9,17,25,26). Test for nitrogen dissimilation.…”

Section: Methodsmentioning

confidence: 99%

“…These results indicate that bacteria able to dissimilate nitrogen are selected in the rhizosphere. Furthermore, the nitrate reductase encoded by narG was recently shown to be involved not only in the rhizospheric competitiveness of Pseudomonas fluorescens C7R12 but more generally in its saprophytic competence in soil environments (17).…”

mentioning

confidence: 99%

Comparative Genetic Diversity of the narG , nosZ , and 16S rRNA Genes in Fluorescent Pseudomonads

Delorme

Philippot

Edel-Hermann

et al. 2003

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

The diversity of the membrane-bound nitrate reductase (narG) and nitrous oxide reductase (nosZ) genes in fluorescent pseudomonads isolated from soil and rhizosphere environments was characterized together with that of the 16S rRNA gene by a PCR-restriction fragment length polymorphism assay. Fragments of 1,008 bp and 1,433 bp were amplified via PCR with primers specific for the narG and nosZ genes, respectively. The presence of the narG and nosZ genes in the bacterial strains was confirmed by hybridization of the genomic DNA and the PCR products with the corresponding probes. The ability of the strains to either reduce nitrate or totally dissimilate nitrogen was assessed. Overall, there was a good correspondence between the reductase activities and the presence of the corresponding genes. Distribution in the different ribotypes of strains harboring both the narG and nosZ genes and of strains missing both genes suggests that these two groups of strains had different evolutionary histories. Both dissimilatory genes showed high polymorphism, with similarity indexes (Jaccard) of between 0.04 and 0.8, whereas those of the 16S rRNA gene only varied from 0.77 to 0.99. No correlation between the similarity indexes of 16S rRNA and dissimilatory genes was seen, suggesting that the evolution rates of ribosomal and functional genes differ. Pairwise comparison of similarity indexes of the narG and nosZ genes led to the delineation of two types of strains. Within the first type, the similarity indexes of both genes varied in the same range, suggesting that these two genes have followed a similar evolution. Within the second type of strain, the range of variations was higher for the nosZ than for the narG gene, suggesting that these genes have had a different evolutionary rate.Denitrification is a microbial process in which oxidized nitrogen compounds are used as alternative electron acceptors for energy production when oxygen is limited. Denitrification consists of four reactions by which nitrate is reduced to dinitrogen by the metalloenzymes nitrate reductase, nitrite reductase, nitric oxide reductase, and nitrous oxide reductase. Bacteria capable of denitrification are frequently isolated from soil environments (30). The most common denitrifiers isolated from temperate soils belong to the group of fluorescent Pseudomonas spp. (8).Zones of high denitrifying activity occur predominantly in specific soil microsites (21) and in "activation sites," such as rhizospheric soil (15). Indeed, the proportion of fluorescent pseudomonads able to reduce nitrates appeared to be significantly higher in the rhizosphere than in the bulk soil. Even more, this proportion increases gradually and significantly in the vicinity of root (4). This observation has been made in the rhizosphere of different plant species cultivated in different soils (5). These results indicate that bacteria able to dissimilate nitrogen are selected in the rhizosphere. Furthermore, the nitrate reductase encoded by narG was recently shown to be involved not only in the ...

show abstract

“…The pyoverdines are characteristic siderophores (1000-1500 Da), composed of three structural parts: dihydroxyquinoline chromophores responsible for fluorescence; a variable peptide part composed of 6-12 amino acids; and a side chain (Meyer 2000, Cornelis andMatthijs 2002). The low biological availability of iron in the soil is improved by the use of P. fluorescens (Loper and Henkels 1999), and the pyoverdine-conferred iron uptake from the rhizosphere (Mirleau et al 2000, Mirleau et al 2001.…”

Section: Determination Of Iron Concentrationmentioning

confidence: 99%

Effect of <i>Pseudomonas fluorescens</i> inoculation on the improvement of iron deficiency in tomato

Nagata

2017

Plant Root

View full text Add to dashboard Cite

with the growth of the control. However, the mechanism of iron absorption has not been clarified yet. Two-week-old seedlings were transferred to a liquid medium inoculated with P. fluorescens. After incubating for four days, the iron concentration of plants increased compared with that of non-symbiotic seedlings. Moreover, the expression of the Fe(II) transporter IRT1 and Nramp3 was analyzed by qRT-PCR. The expression of IRT1 was not induced until day 7 but that of Nramp3 was induced in four days. In addition, Fe(III) chelate reductase (FRO) activity was high in symbiotic seedlings after four days. These results suggest that the chelated Fe(III) was reduced to Fe(II) by FRO and taken up by Nramp3. Siderophore-mediated Fe(III) uptake by tomato is believed to be a useful strategy for increasing iron uptake from the environment.

show abstract

Involvement of Nitrate Reductase and Pyoverdine in Competitiveness of Pseudomonas fluorescens Strain C7R12 in Soil

Cited by 48 publications

References 44 publications

Fluorescent Pseudomonads associated with the rhizosphere of crops: an overview

Fluorescent Pseudomonads associated with the rhizosphere of crops: an overview

Comparative Genetic Diversity of the narG , nosZ , and 16S rRNA Genes in Fluorescent Pseudomonads

Effect of <i>Pseudomonas fluorescens</i> inoculation on the improvement of iron deficiency in tomato

Contact Info

Product

Resources

About