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1.
Ecotoxicol Environ Saf ; 267: 115656, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37944463

RESUMO

Although it is known that microplastics (MPs) in soils cause a threat to this complex environment, the actual effects of MPs on soil microorganisms and their catabolic activities, particularly with the biodegradation of herbicides, remain unclear. Hence, the objective of this study was to investigate the effects of a simultaneous presence of metolachlor and low-density polyethylene (LDPE) microplastics on growth inhibition and adaptive responses of Trichoderma harzianum in soil microcosms. Using ergosterol content as an indicator of fungal biomass, it was observed that MPs alone had a marginal inhibitory effect on the growth of the fungus, whereas MET exhibited a dose-dependent inhibitory effect on T. harzianum. However, the presence of MPs did not influence the fungal transforming activity toward the herbicide. Conversely, analysis of lipid profiles in the presence of MPs and herbicides revealed a reduction in the overall fluidity of phospholipid fatty acids, primarily attributed to an increase in lysophospholipids. The activities of six extracellular enzymes in the soil, measured using methylumbelliferone-linked substrates, were significantly enhanced in the presence of MET. These findings contribute to a broader understanding of the alterations in fungal activity in soil resulting from the influence of MPs and MET.


Assuntos
Herbicidas , Hypocreales , Microplásticos , Plásticos , Polietileno , Herbicidas/toxicidade , Solo
2.
Int J Mol Sci ; 25(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38203274

RESUMO

Proteus mirabilis urinary tract infections can lead to serious complications such as development of urinary stones. Lactobacillus spp., belonging to the natural microbiota of the urinary tract, exhibit a number of antagonistic mechanisms against uropathogens, including the secretion of organic acids. In this study, we determined the anti-adhesion, anti-cytotoxicity and anti-crystallization properties of the substances secreted by Lactobacillus. For this purpose, membrane inserts with a pore diameter 0.4 µm were used, which prevent mixing of cultured cells, simultaneously enabling the diffusion of metabolic products. The intensity of crystallization was assessed by measuring the levels of Ca2+, Mg2+ and NH3 and by observing crystals using microscopic methods. The cytotoxicity of the HCV-29 cell line was determined using the LDH and MTT assays, and the impact of lactobacilli on P. mirabilis adhesion to the bladder epithelium was assessed by establishing CFU/mL after cell lysis. It was shown that in the presence of L. gasseri the adhesion of P. mirabilis and the cytotoxicity of the cells decreased. The degree of crystallization was also inhibited in all experimental models. Moreover, it was demonstrated that L. gasseri is characterized by the secretion of a high concentration of L-lactic acid. These results indicate that L-lactic acid secreted by L. gasseri has a significant impact on the crystallization process and pathogenicity of P. mirabilis.


Assuntos
Microbiota , Sistema Urinário , Proteus mirabilis , Ácido Láctico , Lactobacillus
3.
Int J Mol Sci ; 23(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36361770

RESUMO

While there has been intensive research on the influence of microplastics (MPs) on aquatic organisms and humans, their effect on microorganisms is relatively little-known. The present study describes the response of the Trichoderma harzianum strain to low-density polyethylene (LDPE) microparticles. MPs, either separately or with metolachlor (MET), were added to the cultures. Initially, MP was not found to have a negative effect on fungal growth and MET degradation. After 72 h of cultivation, the content of fungal biomass in samples with MPs was almost three times higher than that in the cultures without MPs. Additionally, a 75% degradation of the initial MET was observed. However, due to the qualitative and quantitative changes in individual classes of phospholipids, cell membrane permeability was increased. Additionally, MPs induced the overproduction of reactive oxygen species. The activity of superoxide dismutase and catalase was also increased in response to MPs. Despite these defense mechanisms, there was enhanced lipid peroxidation in the cultures containing the LDPE microparticles. The results of the study may fill the knowledge gap on the influence of MPs on filamentous fungi. The findings will be helpful in future research on the biodegradation of contaminants coexisting with MPs in soil.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Plásticos , Polietileno/farmacologia , Estresse Oxidativo , Fungos , Poluentes Químicos da Água/farmacologia
4.
Sci Rep ; 11(1): 21319, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34716379

RESUMO

Pyrethroids are chemical insecticides that are widely used to control pests. Entomopathogenic fungi are considered environmentally safe alternatives to these compounds. Pyrethroids and entomopathogenic fungi not only co-exist in the environment but can also be applied together in pest control. They are often found in contact with each other, and thus, it seems important to understand their interactions at the cellular level. In this study, we analyzed whether pyrethroids could influence the phospholipid profile of Beauveria bassiana and whether membrane changes are one of the mechanisms by which these fungi adapt to unfavorable environmental conditions. The results of our study revealed that pyrethroids changed the phospholipid profile and increased the cell membrane permeability of B. bassiana, which enabled them to enter and accumulate within the fungal cells, resulting in oxidative stress. Pyrethroids influenced the amount of neutral lipids, caused a decrease in sodium content, and also temporarily lowered the level of the secondary metabolite oosporein in the studied fungi. These findings indicate that the effect of pyrethroids on entomopathogenic fungi may be more complex than originally thought and that lipidomic studies can aid in fully understanding the influence of these chemicals on the mentioned group of fungi.


Assuntos
Beauveria/efeitos dos fármacos , Piretrinas/efeitos adversos , Beauveria/metabolismo , Agentes de Controle Biológico , Permeabilidade da Membrana Celular/efeitos dos fármacos , Inseticidas/efeitos adversos , Lipidômica , Estresse Oxidativo , Fosfolipídeos/metabolismo
5.
Pestic Biochem Physiol ; 163: 216-226, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31973860

RESUMO

Due to the increasing use of chlorinated organic compounds, environmental pollution is a key issue in agricultural and industrial areas. In this study, biodegradation of chloroacetanilide herbicides, such as alachlor and metolachlor, by eight fungal strains of Trichoderma spp. originating from different microorganism collections was investigated. The tested fungi converted 80-99% of alachlor and 40-79% of metolachlor after 7 days of incubation. Biotransformation of herbicides was performed mainly by dechlorination and hydroxylation reactions. Eight alachlor metabolites and four byproducts of metolachlor conversion were detected in Trichoderma cultures, including two metolachlor intermediates for the first time identified in fungi. Moreover, in the cultures of six Trichoderma strains supplemented with chloroacetanilides, a decrease in toxicity was observed toward tested Artemia franciscana crustaceans. Simultaneously, 7 days after the application of the spores of T. koningii IM 0956, T. citrinoviride IM 6325, T. harzianum KKP 534, T. viride KKP 792 and T. virens DSM 1963 the length of roots and shoots of rapeseed seedlings treated with alachlor or metolachlor significantly increased. All tested strains exhibited plant growth-promoting traits, such as siderophore production, 1-aminocyclopropane-1-carboxylate deaminase (ACCD) activity, and phosphate solubilization, even in the presence of chloroacetanilide herbicides.


Assuntos
Herbicidas , Trichoderma , Acetamidas , Biodegradação Ambiental , Biotransformação
6.
Ecotoxicol Environ Saf ; 184: 109629, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31509783

RESUMO

To investigate the induction of oxidative stress and antioxidant response in the chloroacetanilides-degrading Trichoderma spp. under alachlor and metolachlor exposure, a comparative analysis using popular biomarkers was employed. An increased intracellular level of reactive oxygen species (ROS; especially superoxide anion [O2-]) as well as products of lipid and protein oxidation after 24 h incubation with the herbicides confirmed chloroacetanilide-induced oxidative stress in tested Trichoderma strains. However, the considerable decline in the ROS levels and the carbonyl group content (biomarkers of protein peroxidation) in a time-dependent manner and changes in the antioxidant enzyme activities indicated an active response against chloroacetanilide-induced oxidative stress and the mechanism of tolerance in tested fungi. Moreover, the tested herbicides clearly modified the phospholipids (PLs) content in Trichoderma spp. in the stationary phase of growth, which was manifested through the difference in phosphatidic acid (PA), phosphatidylethanolamine (PE) and phosphatidylcholines (PC) levels. Despite enhanced lipid peroxidation and changes in PLs in most tested fungi, only a slight modification in membrane integrity of Trichoderma spp. under chloroacetanilides exposure was noted. The obtained results suggest that the alterations in the antioxidant system and the PLs profile of Trichoderma spp. might be useful biomarkers of chloroacetanilide-induced oxidative stress.


Assuntos
Herbicidas/metabolismo , Estresse Oxidativo , Fosfolipídeos/metabolismo , Trichoderma/metabolismo , Acetamidas/metabolismo , Acetamidas/toxicidade , Antioxidantes/metabolismo , Biodegradação Ambiental , Herbicidas/toxicidade , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Trichoderma/efeitos dos fármacos
7.
Arch Environ Contam Toxicol ; 76(1): 76-86, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30443665

RESUMO

Animals living in anthropogenic habitats bear a multitude of costs, which are directly or indirectly associated with human activities. Among others, an elevated exposure to environmental pollution can have negative consequences for wildlife populations. We examined the differences in the concentrations of trace elements between the field and forest ecotype of the European roe deer (Capreolus capreolus). Naturally, roe deer inhabited various types of woodlands (forest ecotype), but within the last century, they adapted to life in a human-transformed agricultural areas (field ecotype), which could be associated with an increased exposure to pollution. In this study, we measured concentrations of seven trace metals (barium, copper, iron, lead, manganese, strontium, zinc) and fluoride in skull bones and permanent teeth of more than 230 roe deer from 8 study plots in East-Central Europe. We found that field roe deer had higher concentrations of four trace metals (copper, iron, lead, strontium) and fluoride compared with forest roe deer. These differences were consistent with variations in the general level of environmental contamination within the study plots, as assessed with trace element content in wild plants. Our study indicates that bone and teeth of the European roe deer can be used as a valid indicator of environmental pollution. Also, we expect that elevated exposure of field roe deer to environmental pollution can have negative consequences for wild populations of this species, as well as for the consumers of venison.


Assuntos
Cervos/crescimento & desenvolvimento , Ecótipo , Monitoramento Ambiental/métodos , Fluoretos/análise , Metais Pesados/análise , Oligoelementos/análise , Animais , Animais Selvagens , Osso e Ossos/química , Cervos/metabolismo , Europa (Continente) , Humanos , Dente/química
8.
J Plant Physiol ; 229: 158-163, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30096586

RESUMO

2,4-dichlorophenoxyacetic acid (2,4-D) is among the most commonly used herbicides applied for weed control during wheat cultivation. However, its application could affect wheat growth. The present study investigates the effect of the ascomycetous fungus Trichoderma harzianum on lipid peroxidation, phospholipids, signaling lipids and phospholipase D in the seedlings of wheat (Triticum aestivum L.) treated with 2,4-D (2.5 mg L-1). In the group of 4-day-old seedlings exposed to the herbicide, increased lipid peroxidation and inhibition of growth were observed in shoots and roots. Moreover, elevated levels of oxylipins were noted. Among them, the amount of 13-HOTrE oxygenated from linolenic acid (18:3) increased the most significantly. Concurrently, in the seedlings inoculated with T. harzianum, growth was stimulated when the level of phosphatidylcholine (PC) increased. Moreover, in wheat seedlings treated with 2,4-D and T. harzianum, the level of lipid peroxidation was similar to that in the control and there was no increase observed in oxylipins and phospholipase D activity. T. harzianum might have partly alleviated the toxic effect of 2,4-D on wheat seedlings.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Trichoderma/patogenicidade , Triticum/metabolismo , Triticum/microbiologia , Estresse Oxidativo/fisiologia , Fosfatidilcolinas/metabolismo , Fosfolipase D/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/microbiologia , Triticum/efeitos dos fármacos
9.
Ecotoxicol Environ Saf ; 162: 1-9, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29957402

RESUMO

The filamentous fungus Trichoderma koningii is capable of fast and effective eliminate alachlor (90% after 72 h when added separately and 80-60% in the presence of 1-5 mM of copper). After 168 h over 99% elimination of alachlor resulted in detoxification and was connected with the mitigation of reactive oxygen species (ROS) production. Using MS/MS techniques, seven dechlorinated and hydroxylated metabolites were identified. Cytochrome P450 and laccase participate in biotransformation of the herbicide by this non-ligninolytic fungus. Laccase activity is stimulated both by copper and the mixture of copper and alachlor, which seems to be important for combined pollutants. T. koningii is characterized by high tolerance to copper (up to 7.5 mM). The metal content in mycelia reached 0.9-7.76 mg in 1 g of dry biomass. Our results suggest that T. koningii strain seems to be a promising tool for bioremediation of agricultural areas co-contaminated with copper-based fungicides and chloroacetanilide herbicides.


Assuntos
Acetamidas/metabolismo , Cobre/metabolismo , Herbicidas/metabolismo , Trichoderma/metabolismo , Acetamidas/toxicidade , Biodegradação Ambiental , Biotransformação , Cobre/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Herbicidas/toxicidade , Íons , Lacase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trichoderma/efeitos dos fármacos , Trichoderma/enzimologia
10.
PLoS One ; 13(6): e0199677, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29933393

RESUMO

The study reports the response to herbicide of the 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading fungal strain Umbelopsis isabellina. A comparative analysis covered 41 free amino acids as well as 140 lipid species of fatty acids, phospholipids, acylglycerols, sphingolipids, and sterols. 2,4-D presence led to a decrease in fungal catalase activity, associated with a higher amount of thiobarbituric acid-reactive substances (TBARS). Damage to cells treated with the herbicide resulted in increased membrane permeability and decreased membrane fluidity. Detailed lipidomic profiling showed changes in the fatty acids composition such as an increase in the level of linoleic acid (C18:2). Moreover, an increase in the phosphatidylethanolamine/phosphatidylcholine ratio was observed. Analysis of fungal lipid profiles revealed that the presence of 2,4-D was accompanied by the accumulation of triacylglycerols, a decrease in ergosterol content, and a considerable rise in the level of sphingolipid ceramides. In the exponential phase of growth, increased levels of leucine, glycine, serine, asparagine, and hydroxyproline were found. The results obtained in our study confirmed that in the cultures of U. isabellina oxidative stress was caused by 2,4-D. The herbicide itself forced changes not only to membrane lipids but also to neutral lipids and amino acids, as the difference of tested compounds profiles between 2,4-D-containing and control samples was consequently lower as the pesticide degradation progressed. The presented findings may have a significant impact on the basic understanding of 2,4-D biodegradation and may be applied for process optimization on metabolomic and lipidomic levels.


Assuntos
Ácido 2,4-Diclorofenoxiacético , Membrana Celular/metabolismo , Fungos não Classificados/metabolismo , Herbicidas , Lipídeos de Membrana/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Herbicidas/metabolismo , Herbicidas/farmacologia
11.
Arch Environ Contam Toxicol ; 74(2): 330-338, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29071367

RESUMO

Game animals, such as the roe deer (Capreolus capreolus), have long been used as bioindicators of environmental contamination. Most ecotoxicological research on ungulates has focused on trace element content in soft tissues and antlers. Also, only fragmentary information exists about whether and how trace element concentrations vary with the age of wild-living animals and whether these age-related patterns are similar for different types of tissues. The purpose of this study was to measure concentrations of seven trace metals (barium, copper, iron, lead, manganese, strontium, zinc) and fluoride in bone and teeth of roe deer and to determine whether significant variation is evident with individual age. For this purpose, we collected permanent molars and fragments of mandible bone from more than 130 female roe deer in Central Poland. We found that concentrations of four trace elements (barium, manganese, zinc, and fluoride) in teeth of deer showed positive linear relationships with individual age. No such trends were recorded for trace element content in bone. We suggest that these striking differences in age-related patterns of trace element bioaccumulation between bone and permanent teeth of roe deer might be explained by higher turnover rate and constant remodelling of bone tissue. The results suggest that analysis of permanent teeth may be useful for assessing throughout-life intoxication by environmental pollution in the roe deer and possibly in other mammal species. Our study reinforces the need to carefully account for age-related variation in ecotoxicological research on wild-living animals.


Assuntos
Osso e Ossos/química , Cervos , Metais/análise , Dente/química , Oligoelementos/análise , Animais , Cobre/análise , Poluição Ambiental/análise , Feminino , Fluoretos/análise , Ferro/análise , Fosfatos , Polônia , Zinco/análise
12.
Bioresour Technol ; 197: 404-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26356111

RESUMO

The acceleration of alachlor degradation by Paecilomyces marquandii under controlled and optimized conditions of fungal cultivation in liquid batches was observed (by ca. 20% in comparison to the flask cultures). Acidic environment and oxygen limitation resulted in deterioration of herbicide elimination. Efficient xenobiotic degradation did not correlate with free radicals formation, but some conditions of bioreactor cultivation such as neutral pH and oxygen enriched atmosphere (pO2⩾30%) caused a decrease in the reactive oxygen species (ROS) accumulation in mycelia. The changes in the glutathione (GSH) and ascorbic acid (AA) levels, also in the dismutase (SOD) and catalase (CAT) activities showed active response of the tested fungus against alachlor induced oxidative stress. These results will contribute to the improvement of chloroacetanilides elimination by fungi and extend the knowledge concerning oxidative stress induction and fungal cellular defense.


Assuntos
Acetamidas/metabolismo , Estresse Oxidativo , Paecilomyces/metabolismo , Acetamidas/toxicidade , Ácido Ascórbico/metabolismo , Biodegradação Ambiental , Reatores Biológicos , Biotecnologia/instrumentação , Biotecnologia/métodos , Catalase/metabolismo , Glutationa/metabolismo , Herbicidas/metabolismo , Concentração de Íons de Hidrogênio , Estresse Oxidativo/efeitos dos fármacos , Paecilomyces/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
13.
J Hazard Mater ; 291: 52-64, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-25765177

RESUMO

Alachlor is an herbicide that is widely used worldwide to protect plant crops against broadleaf weeds and annual grasses. However, due to its endocrine-disrupting activity, its application had been banned in the European Union. As described in our earlier work, Paecilomyces marquandii is a microscopic fungus capable of alachlor removal by N-acetyl oxidation. Our current work uses proteomics and metabolomics to gain a better understanding of alachlor biodegradation by the microscopic fungus P. marquandii. The data revealed that the addition of alachlor reduced the culture growth and glucose consumption rates. Moreover, the rates of glycolysis and the tricarboxylic acids (TCA) cycle increased during the initial stage of growth, and there was a shift toward the formation of supplementary materials (UDP-glucose/galactose) and reactive oxygen species (ROS) scavengers (ascorbate). Proteomic analysis revealed that the presence of xenobiotics resulted in a strong upregulation of enzymes related to energy, sugar metabolism and ROS production. However, the unique overexpression of cyanide hydratase in alachlor-containing cultures may implicate this enzyme as the key protein involved in the alachlor biodegradation pathway. The characterization of P. marquandii-mediated alachlor removal in terms of cell structure and function provides a deeper insight into the strategies of microorganisms toward xenobiotic biodegradation.


Assuntos
Acetamidas/metabolismo , Biodegradação Ambiental , Herbicidas/metabolismo , Metabolômica/métodos , Paecilomyces/metabolismo , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/isolamento & purificação , Glucose/análise , Glucose/metabolismo , Paecilomyces/genética , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Environ Sci Pollut Res Int ; 21(6): 4228-35, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24306727

RESUMO

To investigate the response of the tributyltin-degrading fungal strain Cunninghamella elegans to the organotin, a comparative lipidomics strategy was employed using an LC/MS-MS technique. A total of 49 lipid species were identified. Individual phospholipids were then quantified using a multiple reaction monitoring method. Tributyltin (TBT) caused a decline in the amounts of many molecular species of phosphatidylethanolamine or phosphatidylserine and an increase in the levels of phosphatidic acid, phosphatidylinositol and phosphatidylcholine. In the presence of TBT, it was observed that overall unsaturation was lower than in the control. Lipidome data were analyzed using principal component analysis, which confirmed the compositional changes in membrane lipids in response to TBT. Additionally, treatment of fungal biomass with butyltin led to a significant increase in lipid peroxidation. It is suggested that modification of the phospholipids profile and lipids peroxidation may reflect damage to mycelium caused by TBT.


Assuntos
Cunninghamella/efeitos dos fármacos , Substâncias Perigosas/toxicidade , Estresse Oxidativo , Compostos de Trialquitina/toxicidade , Cromatografia Líquida , Cunninghamella/fisiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos , Lipídeos de Membrana/metabolismo , Fosfolipídeos/metabolismo
15.
J Hazard Mater ; 261: 443-50, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23974531

RESUMO

Alachlor, a popular chloroacetanilide herbicide, can be a potential health risk factor. Soil microorganisms are primarily responsible for conversion and migration of alachlor in natural environment, but knowledge concerning alachlor biodegradation is not complete. Therefore, we studied the ability of Paecilomyces marquandii, soil fungus tolerant to heavy metals, to eliminate alachlor and proposed a new pathway of its transformation. After 7 days of incubation only 3.3% of alachlor was detected from an initial concentration 50 mg L(-1) and 20.1% from a concentration 100 mg L(-1). The qualitative IDA LC-MS analysis showed the presence of ten metabolites. All of them were dechlorinated mainly through oxidation, but also reductive dechlorination was observed. The main route of alachlor conversion progressed via N-acetyl oxidation resulting in the formation of mono-, di- and trihydroxylated byproducts. N-acetyl oxidation as a dominant route of alachlor metabolism by fungi has not been described so far. The toxicity of alachlor tested with Artemia franciscana did not increase after treatment with P. marquandii cultures. Paecilomyces marquandii strain seems to be an interesting model for the research on alachlor conversion by soil microscopic fungi, due to its dechlorination and hydroxylation ability as well as high tolerance to heavy metals.


Assuntos
Acetamidas/metabolismo , Herbicidas/metabolismo , Paecilomyces/metabolismo , Poluentes do Solo/metabolismo , Acetamidas/toxicidade , Animais , Crustáceos/efeitos dos fármacos , Inibidores das Enzimas do Citocromo P-450 , Herbicidas/toxicidade , Oxirredução , Paecilomyces/efeitos dos fármacos , Paecilomyces/crescimento & desenvolvimento , Poluentes do Solo/toxicidade
16.
J Plant Physiol ; 170(4): 369-77, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23374731

RESUMO

In this study, we analyzed the toxic effect of Ni during the development of wheat shoots. Typical developmental alterations in carbon metabolism-related parameters reflecting changes associated with the transition of the seedlings from heterotrophic to autotrophic metabolism were observed in the control shoots between the 1st and the 4th days. Adverse effects of 50 and 100 µM Ni became evident starting from the 4th day of growth on the metal-containing media. We found that Ni-induced stimulation of phosphoenolpyruvate carboxylase (PEPC) activity coincided with decrease in the ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) level and with declines in net photosynthetic rate (P(N)) and stomatal conductance (g(s)). Application of Ni resulted in increased activities of several dehydrogenases: glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), isocitrate dehydrogenase (NADP-ICDH) and malate dehydrogenase (NADH-MDH). In contrast, the activities of malic enzymes (NADP-ME and NAD-ME) decreased due to Ni stress. Treatment with Ni led to accumulation of glucose and declined concentration of sucrose as well as considerable increases in concentrations of malic and citric acids. Our results indicate that Ni stress redirects the carbon metabolism of developing wheat shoots to provide carbon skeletons for synthesis of amino acids and organic acids as well as to supply reducing power to sustain normal metabolic processes and to support defense mechanisms against oxidative stress.


Assuntos
Carbono/metabolismo , Níquel/toxicidade , Brotos de Planta/crescimento & desenvolvimento , Triticum/efeitos dos fármacos , Triticum/metabolismo , Ativação Enzimática/efeitos dos fármacos , Fosfoenolpiruvato Carboxilase/metabolismo , Fotossíntese/efeitos dos fármacos , Estômatos de Plantas/efeitos dos fármacos , Ribulose-Bifosfato Carboxilase/metabolismo
17.
Acta Biochim Pol ; 60(4): 695-700, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24432319

RESUMO

In this work we compared the effect of five heavy metals: Zn, Pb, Cd, Ni and Cu on phospholipid composition of the ubiquitous soil fungus Paecilomyces marquandii, originating from a strongly metal polluted area and characterized by high tolerance to these elements. Cd, Ni and Cu caused an increase in phosphatidylcholine (PC). Only Pb decreased PC content, which was accompanied by a significant rise in the phosphatidic acids (PA) level, probably due to activation of phospholipase D which hydrolyzes PC to PA. This could result in membrane fluidity disturbance, and thus affect its integrity. The assessment of propidium iodide influx showed strong disturbance of membrane integrity for Cu and Pb stressed mycelia, whereas mycelia treated with Ni were impermeable to this dye. The results obtained revealed a strong Cu and Pb toxicity involving disruption of membrane integrity. Pb action was reflected by lipid composition, whereas changes in Cu treated mycelia did not completely elucidate its harmful effect on the membrane, which was most probably caused by Cu induced lipid peroxidation. Zn did not induce quantitative changes in PC and phosphatidylethanolamine (PE) but caused changes in phospholipid lipid saturation, which appears to be important for fungus adaptation to the presence of metals. The enhanced PC content balanced by higher PC saturation can help in the maintenance of proper membrane fluidity and result in alleviating the Cd and Ni induced stress. These results will allow to clarify the mechanism of Pb toxicity and help to elucidate the cellular basis of fungal membrane adaptation to heavy metals.


Assuntos
Membrana Celular/efeitos dos fármacos , Intoxicação por Metais Pesados , Paecilomyces/efeitos dos fármacos , Intoxicação , Cádmio/toxicidade , Membrana Celular/química , Membrana Celular/metabolismo , Paecilomyces/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Poluentes do Solo/toxicidade
18.
Environ Sci Pollut Res Int ; 20(5): 3423-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23132407

RESUMO

The ability of the heavy metal-tolerant fungus Paecilomyces marquandii to modulate whole cells fatty acid composition and saturation in response to IC50 of Cd, Pb, Zn, Ni, and Cu was studied. Cadmium and nickel caused the most significant growth reduction. In the mycelia cultured with all tested metals, with the exception of nickel, a rise in the fatty acid unsaturation was noted. The fungus exposure to Pb, Cu, and Ni led to significantly higher lipid peroxidation. P. marquandii incubated in the presence of the tested metals responded with an increase in the level of linoleic acid and escalation of electrolyte leakage. The highest efflux of electrolytes was caused by lead. In these conditions, the fungus was able to bind up to 100 mg g(-1) of lead, whereas the content of the other metals in the mycelium was significantly lower and reached from 3.18 mg g(-1) (Cu) to 15.21 mg g(-1) (Zn). Additionally, it was shown that ascorbic acid at the concentration of 1 mM protected fungal growth and prevented the changes in the fatty acid composition and saturation but did not alleviate lipid peroxidation or affect the increased permeability of membranes after lead exposure. Pro-oxidant properties of ascorbic acid in the copper-stressed cells manifested strong growth inhibition and enhanced metal accumulation as a result of membrane damage. Toxic metals action caused cellular modulations, which might contributed to P. marquandii tolerance to the studied metals. Moreover, these changes can enhance metal removal from contaminated environment.


Assuntos
Exposição Ambiental , Poluentes Ambientais/toxicidade , Metais Pesados/toxicidade , Paecilomyces/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Condutometria , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Paecilomyces/metabolismo , Espectrofotometria Atômica , Substâncias Reativas com Ácido Tiobarbitúrico/química
19.
Curr Microbiol ; 59(3): 315-20, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19533231

RESUMO

The purpose of the presented paper was to study the effect of high concentrations of tributyltin (TBT) on the potassium retention and fatty acid (FA) composition of the fungus Cunninghamella elegans recognized as a very efficient TBT degrader. An increase in TBT had a strong influence on the potassium concentration in the fungus. In growth medium without TBT, the potassium content of the fungal cells was 5.8 mg K(+) g dry weight(-1). The maximum concentration of K(+) was 15.06 mg g(-1) dry weight at 30 mg l(-1) of TBT. The major FAs that characterized the tested strain were C16:0, C18:1, C18:2, C18:3 and C18:0. TBT in the concentration range 5-30 mg l(-1) strongly influenced the FA composition. In the presence of the organotin, the degree of saturation increased. It suggests that the observed changes promote an increase in the lipid ordering of the membrane by reducing its permeability and inhibiting potassium ion efflux.


Assuntos
Cunninghamella/efeitos dos fármacos , Cunninghamella/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Potássio/metabolismo , Compostos de Trialquitina/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos
20.
Sci Total Environ ; 407(13): 4127-33, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19394071

RESUMO

Microbial ability vary when pollutants exist together in the environment in comparison to the presence of single toxic compound. The influence of alachlor and zinc on the growth of the filamentous fungus Paecilomyces marquandii and its ability to eliminate alachlor and zinc has been studied. Their simultaneous presence in the polluted environment is very probable. In liquid cultures the pesticide (50 mg/l) was removed with the efficiency of 85% within 7 days. Beginning from the third day of culturing two derivatives of alachlor were found: N-(2',6'-diethylphenyl)-N-metoxymethyl-acetamide and unstable 2-chloro-N-(2',6'-diethylphenyl)-N-hydroxymethyl-acetamide, the first time detected as product of alachlor metabolisation by filamentous fungus. The herbicide elimination was not inhibited by zinc up to 1.0 mM of the metal content in the culture medium, 5.0-7.5 mM of the metal limited alachlor depletion by 30-50%, whereas a higher zinc concentration stopped this process. Zinc content in P. marquandii mycelium during the incubation in growth medium reached 10-20 mg/g of dry weight and was increased up to 99 mg/g by alachlor, however due to its presence a strong inhibitory effect on growth was observed. It was postulated that the increase in zinc binding by the growing mycelium of P. marquandii in the presence of the pesticide was connected with the changes in the wall and membrane composition induced by simultaneous toxic interaction of zinc and alachlor. Only 15-20% of bound zinc was detected in the cell wall of the fungus, whereas the amount of zinc loaded in the wall of mycelium originating from the cultures incubated in the alachlor presence increased to 60%. Additionally, changes in the profile of fatty acids of cultures with pesticide and metal addition were observed. P. marquandii strain seems to be promising for a potential industrial application. It can both effectively bind zinc and remove alachlor from the mixture of pollutants.


Assuntos
Acetamidas/toxicidade , Herbicidas/toxicidade , Paecilomyces/metabolismo , Zinco/toxicidade , Acetamidas/metabolismo , Herbicidas/metabolismo , Zinco/metabolismo
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