Indigenous microflora and bean responses to introduction of genetically modified<i>pseudomonas fluorescens</i>strains into soil contaminated with copper

Kozdrój, Jacek; Piotrowska‐Seget, Zofia

doi:10.1080/10934529509376329

“…As previously described for other bacteria [21,22], additional CuSO 4 supplementation led to toxic effects in diazotrophic A. chroococcum cells in liquid culture when provided at super-optimal concentrations (>5 mM). At moderate CuSO 4 concentrations (1-5 mM), the effects on extracellular melanin production were only marginal; however, the cells were found to earlier produce cellassociated melanin in the presence of elevated copper concentrations.…”

Section: Discussionsupporting

confidence: 58%

“…Besides their participation in cellular differentiation processes, an interesting facet of prokaryotic PO is their mediation in metal ion toxicity and their role in the efflux of metals such as copper . Although acting as a growth‐inhibiting heavy metal when present at super‐optimal concentrations , copper ions in particular were previously described as causing increased cellular pigment production, in addition to enhanced PO expression and activation .…”

Section: Introductionmentioning

confidence: 99%

Investigating the effects of metals on phenol oxidase‐producing nitrogen‐fixing Azotobacter chroococcum

Herter

¹

,

Schmidt

²

,

Thompson

³

et al. 2012

J. Basic Microbiol

1

0

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Expression of phenol oxidases (PO) in bacteria is often observed during physiological and morphological changes; in the nitrogen-fixing strain Azotobacter chroococcum SBUG 1484, it is accompanied by the formation of encysted cells and melanin. Herein, we studied the effects of copper and the depletion of the nitrogenase-relevant metals molybdenum and iron on physiological characteristics such as culture pigmentation, release of ortho-dihydroxylated melanin precursors, and expression of PO activity in A. chroococcum. Biomass production and melanogenic appearance were directly affected by the depletion of either iron or molybdenum, or in the absence of both metals. Only nitrogen-fixing cells growing in the presence of both metals and cultures supplemented with iron (molybdenum starved) showed the ability to produce an intensively brown-black melanin pigment typically associated with A. chroococcum. Accordingly, PO production was only detected in the presence of both metals and in iron-supplemented cultures starved of molybdenum. The total amount of catecholate siderophores produced by nitrogen-fixing melanogenic cells was considerably higher than in cultures starved of metal ions. Induction of enhanced PO activity was stimulated by additional copper sulfate, possibly related to cellular processes involved in the detoxification of this particular metal, and revealed distinct release of the ortho-dihydroxylated melanin precursors catechol and 3,4-dihydroxybenzoic acid.

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“…are considered to be K-strategists, growing much slower while at the same time forming long term survival structures (De Leij et al, 1995, Juteau et al, 1999, Polyanskaya et al, 2002. K-strategists adapt to survival under crowded nutrient deficient conditions and are more resistant to various environmental stressers (Kozdroj et al, 1995). Therefore it is possible that the Clostridium and Rhodococcus spp.…”

Section: Molecular Work and Identification Of Mixed Community Membersmentioning

confidence: 99%

First steps in assessing microbial involvement in the geochemical evolution of uranium mine tailings : evaluation of iron reduction potential, biofilm formation and community heterogeneity

Guran¹

2021

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“…are considered to be K-strategists, growing much slower while at the same time forming long term survival structures (De Leij et al, 1995, Juteau et al, 1999, Polyanskaya et al, 2002. K-strategists adapt to survival under crowded nutrient deficient conditions and are more resistant to various environmental stressers (Kozdroj et al, 1995). Therefore it is possible that the Clostridium and Rhodococcus spp.…”

Section: Molecular Work and Identification Of Mixed Community Membersmentioning

confidence: 99%

First steps in assessing microbial involvement in the geochemical evolution of uranium mine tailings : evaluation of iron reduction potential, biofilm formation and community heterogeneity

Guran¹

2021

Preprint

0

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Indigenous microflora and bean responses to introduction of genetically modifiedpseudomonas fluorescensstrains into soil contaminated with copper

Cited by 5 publications

References 46 publications

Investigating the effects of metals on phenol oxidase‐producing nitrogen‐fixing Azotobacter chroococcum

Investigating the effects of metals on phenol oxidase‐producing nitrogen‐fixing Azotobacter chroococcum

First steps in assessing microbial involvement in the geochemical evolution of uranium mine tailings : evaluation of iron reduction potential, biofilm formation and community heterogeneity

First steps in assessing microbial involvement in the geochemical evolution of uranium mine tailings : evaluation of iron reduction potential, biofilm formation and community heterogeneity

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