Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
PLoS One ; 19(3): e0300485, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38470886

RESUMEN

The wastewater from underground coal gasification (UCG) process has extremely complex composition and high concentrations of toxic and refractory compounds including phenolics, aliphatic and aromatic hydrocarbons, ammonia, cyanides, hazardous metals and metalloids. So, the development of biological processes for treating UCG wastewater poses a serious challenge in the sustainable coal industry. The aim of the study was to develop an innovative and efficient wetland construction technology suitable for a treatment of UCG wastewater using available and low-cost media. During the bioremediation process the toxicity of the raw wastewater decreased significantly between 74%-99%. The toxicity units (TU) ranged from values corresponding to very high acute toxic for raw wastewater to non-toxic for effluents from wetland columns after 60 days of the experiment. The toxicity results correlated with the decrease of some organic and inorganic compounds such as phenols, aromatic hydrocarbons, cyanides, metals and ammonia observed during the bioremediation process. The removal percentage of organic compounds like BTEX, PAHs and phenol was around 99% just after 14 days of treatment. A similar removal rate was indicated for cyanide and metals (Zn, Cr, Cd and Pb). Concluded, in order to effectively assess remediation technologies, it is desirable to consider combination of physicochemical parameters with ecotoxicity measurements. The present findings show that wetland remediation technology can be used to clean-up the heavily contaminated waters from the UCG process. Wetland technology as a nature-based solution has the potential to turn coal gasification wastewater into usable recycled water. It is economically and environmentally alternative treatment method.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Carbón Mineral , Amoníaco , Humedales , Fenoles , Metales , Cianuros , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis
2.
Sci Rep ; 13(1): 14618, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37670040

RESUMEN

The amounts of anthropogenic pollutants, e.g., microplastics (MPs) and pesticides, in terrestrial and aquatic ecosystems have been increasing. The aim of this study was to assess the influence of MPs on the removal of herbicides (metolachlor, MET; 2,4-dichlorophenoxyacetic acid, 2,4-D) and the production of biosurfactants (surfactin and iturin) by Bacillus sp. Kol L6 active against Fusarium culmorum. The results showed that Kol L6 eliminated 40-55% MET and 2,4-D from liquid cultures, but this process was inhibited in the presence of MPs. Although the pollutants did not strongly limit the production of surfactin, iturin secretion was found to decrease by more than 70% in the presence of all three pollutants. Interestingly, the strongest modification in the profile of iturin homologues was calculated for the cultures containing MET + MP and 2,4-D + MET + MP. The bacteria significantly limited the growth of the phytopathogenic F. culmorum DSM1094F in the presence of individual pollutants and their two-component mixtures. However, in the presence of all three tested pollutants, the growth of the fungus was limited only partially (by no more than 40%). The presented results are a starting point for further research on bacteria-fungi-plants interactions in the soil environment in the presence of multiple pollutants.


Asunto(s)
Bacillus , Contaminantes Ambientales , Herbicidas , Microplásticos , Plásticos , Ecosistema , Ácido 2,4-Diclorofenoxiacético
3.
Environ Pollut ; 313: 119989, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36028079

RESUMEN

The composition of root exudates is modulated by several environmental factors, and it remains unclear how that affects beneficial rhizosphere or inoculated microorganisms under heavy metal (HM) contamination. Therefore, we evaluated the transcriptional response of Pseudomonas putida E36 (a Miscanthus x giganteus isolate with plant growth promotion-related properties) to Cd, Pb and Zn in an in vitro study implementing root exudates from M. x giganteus. To collect root exudates and analyse their composition plants were grown in a pot experiment under HM and control conditions. Our results indicated higher exudation rate for plants challenged with HM. Further, out of 29 organic acids identified and quantified in the root exudates, 8 of them were significantly influenced by HM (e.g., salicylic and terephthalic acid). The transcriptional response of P. putida E36 was significantly affected by the HM addition to the growth medium, increasing the expression of several efflux pumps and stress response-related functional units. The additional supplementation of the growth medium with root exudates from HM-challenged plants resulted in a downregulation of 29% of the functional units upregulated in P. putida E36 as a result of HM addition to the growth medium. Surprisingly, root exudates + HM downregulated the expression of P. putida E36 functional units related to plant colonization (e.g., chemotaxis, motility, biofilm formation) but upregulated its antibiotic and biocide resistance compared to the control treatment without HM. Our findings suggest that HM-induced changes in root exudation pattern may attract beneficial bacteria that are in turn awarded with organic nutrients, helping them cope with HM stress. However, it might affect the ability of these bacteria to colonize plants growing in HM polluted areas. Those findings may offer an insight for future in vivo studies contributing to improvements in phytoremediation measures.


Asunto(s)
Desinfectantes , Metales Pesados , Pseudomonas putida , Contaminantes del Suelo , Antibacterianos , Biodegradación Ambiental , Cadmio , Exudados y Transudados/química , Exudados y Transudados/metabolismo , Plomo , Metales Pesados/toxicidad , Exudados de Plantas , Raíces de Plantas/metabolismo , Plantas/metabolismo , Poaceae , Pseudomonas putida/metabolismo , Contaminantes del Suelo/análisis
4.
Biomolecules ; 12(8)2022 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-36009054

RESUMEN

The aim of this study was to quantify ESKAPEE bacteria, genes encoding resistance to antibiotics targeting this group of pathogens, as well as integrase genes in municipal wastewater and river water. Environmental DNA was extracted from the collected samples and used in deep sequencing with the Illumina TruSeq kit. The abundance of bacterial genera and species belonging to the ESKAPEE group, 400 ARGs associated with this microbial group, and three classes of integrase genes were determined. A taxonomic analysis revealed that Acinetobacter was the dominant bacterial genus, whereas Acinetobacter baumannii and Escherichia coli were the dominant bacterial species. The analyzed samples were characterized by the highest concentrations of the following ARGs: blaGES, blaOXA-58, blaTEM, qnrB, and qnrS. Acinetobacter baumannii, E. coli, and genes encoding resistance to ß-lactams (blaVEB-1, blaIMP-1, blaGES, blaOXA-58, blaCTX-M, and blaTEM) and fluoroquinolones (qnrS) were detected in samples of river water collected downstream from the wastewater discharge point. The correlation analysis revealed a strong relationship between A. baumannii (bacterial species regarded as an emerging human pathogen) and genes encoding resistance to all tested groups of antimicrobials. The transmission of the studied bacteria (in particular A. baumannii) and ARGs to the aquatic environment poses a public health risk.


Asunto(s)
Acinetobacter baumannii , Aguas Residuales , Acinetobacter baumannii/genética , Antibacterianos/análisis , Antibacterianos/farmacología , Bacterias/genética , Escherichia coli , Humanos , Integrasas , Polonia , Agua/análisis
5.
Colloids Surf B Biointerfaces ; 213: 112404, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35151043

RESUMEN

The aim of this study was to obtain stable star polymer layers with incorporated silver nanoparticles (AgNPs) and to study the antimicrobial activity of these hybrid materials. In this work, a novel approach regarding the synthesis of AgNPs directly by the star polymer layer is presented. Nanolayers of poly(N,N'-dimethylaminoethyl methacrylate) and hydroxyl-bearing poly[oligo(ethylene glycol) methacrylate] (P(DMAEMA-co-OEGMA-OH)) stars, covalently bound with solid supports, were obtained through chemical reaction of hydroxyl groups in the star arms with substrate modified with imidazole derivative. Quantitative chemical composition analysis and tracking of the changes in the morphology and wettability after every step of surface modification confirmed the covalent attachment of stars with the support. In the next step, the polymer nanolayers were modified with AgNPs formed in situ using only amine groups of the star arms and followed by the crystal quartz microbalance (QCM). The analysis of the layer thickness and affinity to water, both with the shape, size and amount of silver incorporated into the layer, confirmed the efficacy of AgNPs formation. The amount of silver incorporated into layers was correlated with the molar masses of the grafted stars, and a possible location of AgNPs within layers was shown. The antibacterial activity tests of prepared nanolayers showed that obtained hybrid materials were highly effective against both gram-positive and gram-negative bacteria strains. This study shows that the obtained layers are promising as stable coatings for antibacterial applications.


Asunto(s)
Nanopartículas del Metal , Plata , Antibacterianos/química , Bacterias Gramnegativas , Bacterias Grampositivas , Nanopartículas del Metal/química , Metacrilatos/farmacología , Pruebas de Sensibilidad Microbiana , Polímeros/farmacología , Plata/química , Plata/farmacología
6.
PLoS One ; 16(6): e0252691, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34086804

RESUMEN

The spread of antibiotic resistance is closely related with selective pressure in the environment. Wastewater from industrialized regions is characterized by higher concentrations of these pollutants than sewage from less industrialized areas. The aim of this study was to compare the concentrations of contaminants such as antibiotics and heavy metals (HMs), and to evaluate their impact on the spread of genes encoding resistance to antimicrobial drugs in samples of wastewater, sewage sludge and river water in two regions with different levels of industrialization. The factors exerting selective pressure, which significantly contributed to the occurrence of the examined antibiotic resistance genes (ARGs), were identified. The concentrations of selected gene copy numbers conferring resistance to four groups of antibiotics as well as class 1 and 2 integron-integrase genes were determined in the analyzed samples. The concentrations of six HMs and antibiotics corresponding to genes mediated resistance from 3 classes were determined. Based on network analysis, only some of the analyzed antibiotics correlated with ARGs, while HM levels were correlated with ARG concentrations, which can confirm the important role of HMs in promoting drug resistance. The samples from a wastewater treatment plant (WWTP) located an industrialized region were characterized by higher HM contamination and a higher number of significant correlations between the analyzed variables than the samples collected from a WWTP located in a less industrialized region. These results indicated that treated wastewater released into the natural environment can pose a continuous threat to human health by transferring ARGs, antibiotics and HMs to the environment. These findings shed light on the impact of industrialization on antibiotic resistance dissemination.


Asunto(s)
Antibacterianos/análisis , Agua Dulce/análisis , Metales Pesados/análisis , Aguas del Alcantarillado/análisis , Aguas Residuales/análisis , Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/aislamiento & purificación , Farmacorresistencia Microbiana/genética , Agua Dulce/microbiología , Desarrollo Industrial , Integrasas/genética , Integrones/genética , Límite de Detección , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos , Aguas Residuales/microbiología
7.
PLoS One ; 16(4): e0250514, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33901216

RESUMEN

Due to limited description of the role and diversity of archaea in WWTPs, the aim of the study was to analyze microbial community structures and diversities with particular regard to Archaea in the samples taken from different stages of the full-scale municipal wastewater treatment plant and effluent receiving water (upstream and downstream discharge point). Our study was focused on showing how the treatment processes influenced the Eubacteria and Archaea composition. Alpha and Beta diversity were used to evaluate the microbial diversity changes in the collected samples. Proteobacteria was the largest fraction ranging from 28% to 67% with 56% relative abundance across all samples. Archaea were present in all stages of WWTP ranged from 1 to 8%. Among the Archaea, two groups of methanogens, acetoclastic (Methanosarcina, Methanosaeta) and hydrogenotrophic methanogens (Methanospirillium, Methanoculleus, Methanobrevibacter) were dominant in the technological stages. The obtained results indicate that the treated wastewater did not significantly affect eubacterial and archaeal composition in receiving water. However, differences in richness, diversity and microbial composition of Eubacteria and Archaea between the wastewater samples taken from the primary and secondary treatment were observed.


Asunto(s)
Archaea/aislamiento & purificación , Biodiversidad , Microbiota , Purificación del Agua , Bacterias/aislamiento & purificación , Ciudades , Filogenia , Análisis de Componente Principal
8.
Artículo en Inglés | MEDLINE | ID: mdl-35010596

RESUMEN

The present study was focused on the identification of multi-resistant bacteria from the WHO priority pathogens list in the samples taken from different stages of the full-scale municipal wastewater treatment plant and receiving water. Additionally, the seasonal variations of the selected multi-resistant pathogens were analyzed in the samples. In order to the aim of the study, the metagenomic DNA from the collected samples was isolated and sequenced. The samples were collected in three campaigns (spring, summer, autumn). Metagenomic DNA was isolated by the commercial kits, according to the manufacturer's instruction. Illumina sequencing system was employed, and the R program was used to metagenomic analysis. It was found that the wastewater samples and receiving water contained the multi-resistant bacteria from the WHO priority pathogens list. The seasonal and technological variations affected the distribution of the pathogens in the wastewater. No effect of the effluent on the pathogens in the receiving water was observed. The results indicated that antibiotic-resistant "priority pathogens" from the WHO list are there in the waste- and receiving water. Technological process and seasons effected their distribution in the environment. Metagenomic analysis can be used as sufficient tool in microbiological and human health risk assessment.


Asunto(s)
Purificación del Agua , Agua , Antibacterianos , Humanos , Estaciones del Año , Aguas Residuales , Organización Mundial de la Salud
9.
Int J Environ Health Res ; 31(4): 401-420, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31509014

RESUMEN

The microbial world provides new energy sources and many various 'green' chemicals. One type of chemicals produced by microorganisms is the biosurfactant group. Biosurfactants are universal molecules, exhibiting surface properties often accompanied by desired biological activity. Biosurfactants are considered to be environmentally 'friendly' due to their low toxicity and biodegradable nature. These compounds have unique features and therefore they can find potential applications in many different industries, ranging from biotechnology to environmental remediation technologies. Antibacterial and antifungal activities make them relevant for applications as inhibitory agents against microbial biofilm. This review covers the current knowledge and the recent advances in the field of biosurfactants as antibiofilm agents.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Hongos/efectos de los fármacos , Tensoactivos/farmacología , Fenómenos Fisiológicos Bacterianos/efectos de los fármacos , Hongos/fisiología
10.
Microb Drug Resist ; 27(2): 179-189, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32552456

RESUMEN

The study provides data on antibiotic resistance as well as the virulence characteristics of Aeromonas caviae isolated from raw and treated wastewater. The isolates were identified as A. caviae by 16S rRNA gene sequencing. In the analyzed strains, high frequency for the following genes was observed: aac(6')-Ib-cr, qnrB, and qnrD. The presence of qnrA and ogxB genes was not found in any strain. The higher frequency of the investigated genes was observed in strains from raw wastewater (RW). The strains of A. caviae showed multiple antibiotic resistance evaluated by the disk diffusion method. Multiple antibiotic resistance indices ranged from 0.36 to 0.69. Susceptibility to six heavy metals (Cd+2, Zn+2, Cu+2, Co+2, Mn+2, and Ni+2) was recorded for all the isolates. The order of metal resistance of A. caviae was Co > Cu > Zn > Cd > Ni > Mn. All the strains of A. caviae showed ß-hemolytic activity. Enzymes of amylase, cellulase, and lipase were produced by all isolates. Only the strains from RW had the ability to form biofilms and showed motility. The obtained results indicate that wastewater is a potential source and/or reservoir of virulent and multidrug-resistant A. caviae as "high-risk isolates."


Asunto(s)
Aeromonas caviae/genética , Farmacorresistencia Microbiana/efectos de los fármacos , Farmacorresistencia Microbiana/genética , Fluoroquinolonas/farmacología , Virulencia/genética , Aguas Residuales/microbiología , Amilasas/genética , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Celulasa/genética , Genes Bacterianos/genética , Lipasa/genética , Metales Pesados/farmacología , Pruebas de Sensibilidad Microbiana/métodos , ARN Ribosómico 16S/genética
11.
Microbiol Resour Announc ; 9(40)2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33004446

RESUMEN

The presented data provide new information on antibiotic resistance and virulence genes in the genomes of Aeromonas caviae strains TW-2 and TW-6, isolated from treated wastewater. The results confirm the presence of multi-antibiotic-resistant Aeromonas caviae strains with virulence properties as "high-risk isolates" in treated wastewater.

12.
Int J Mol Sci ; 21(15)2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32752269

RESUMEN

This study presents a new, simple way to obtain mesoporous calcite structures via a green method using an eco-friendly surface-active compound, surfactin, as a controlling agent. The effects of synthesis time and surfactin concentration were investigated. The obtained structures were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) coupled with gas mass spectrometry (QMS) analysis. The experimental data showed that surfactin molecules significantly changed the morphology of the calcite crystals, roughening and deforming the surface and creating a greater specific surface area, even at low biosurfactant concentrations (10 ppm). The size of the crystals was reduced, and the zeta potential value of calcium carbonate was more negative when more biosurfactant was added. The XRD data revealed that the biomolecules were incorporated into the crystals and slowed the transformation of vaterite into calcite. It has been shown that as long as vaterite is present in the medium, the calcite surface will be less deformed. The strong influence of surfactin molecules on the crystal growth of calcium carbonate was due to the interaction of surfactin molecules with free calcium ions in the solution as well as the biomolecules adsorption at the formed crystal surface. The role of micelles in crystal growth was examined, and the mechanism of mesoporous calcium carbonate formation was presented.


Asunto(s)
Carbonato de Calcio/química , Calcio/química , Lipopéptidos/química , Micelas , Algoritmos , Rastreo Diferencial de Calorimetría , Cristalización , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Termodinámica , Termogravimetría , Factores de Tiempo , Difracción de Rayos X
13.
Cryobiology ; 96: 145-151, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32702362

RESUMEN

The objective of this study was to research the effect of the freeze-drying process on the metabolic changes of Pseudomonas putida strains (E41, E42, R85) isolated from the interior of Sida hermaphrodita roots with the use of the phenotypic microarrays (PM) technology. The proposed method of the freeze-drying process with inulin as component lycoprotectant demonstrated a high bacterial survival ratio (BSR) immediately after freeze-drying and storage after 12 months. While, after 360 days of freeze-drying BSR decreased to value of 74.38. Pseudomonas putida strains were assayed on microplates PM1-PM5, and PM9-PM13 testing 664 different substrates. However, no significant differences in the use of C substrates were observed either before or after the freeze drying process. An insignificant negative effect of the freeze-drying on the use of these substrates was observed. The utilization of N, P and S sources was low or showed no metabolic activity for most of the compounds after freeze-drying. The freeze-drying process increased the sensitivity of the bacteria to antibiotics and selected chemicals. In this study, the freeze-drying process decreased the metabolic activities of the tested strains and their resistance to antibiotics and chemicals.


Asunto(s)
Pseudomonas putida , Criopreservación/métodos , Liofilización , Fenotipo , Raíces de Plantas
14.
Int J Mol Sci ; 21(6)2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32245097

RESUMEN

Corrosion influenced by microbes, commonly known as microbiologically induced corrosion (MIC), is associated with biofilm, which has been one of the problems in the industry. The damages of industrial equipment or infrastructures due to corrosion lead to large economic and environmental problems. Synthetic chemical biocides are now commonly used to prevent corrosion, but most of them are not effective against the biofilms, and they are toxic and not degradable. Biocides easily kill corrosive bacteria, which are as the planktonic and sessile population, but they are not effective against biofilm. New antimicrobial and eco-friendly substances are now being developed. Biosurfactants are proved to be one of the best eco-friendly anticorrosion substances to inhibit the biocorrosion process and protect materials against corrosion. Biosurfactants have recently became one of the important products of bioeconomy with multiplying applications, while there is scare knowledge on their using in biocorrosion treatment. In this review, the recent findings on the application of biosurfactants as eco-friendly and innovative biocides against biocorrosion are highlighted.


Asunto(s)
Desinfectantes/farmacología , Tensoactivos/farmacología , Bacterias/efectos de los fármacos , Corrosión , Pruebas de Sensibilidad Microbiana
15.
Molecules ; 25(6)2020 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-32213976

RESUMEN

In this study, a screening of 26 selected antimicrobials using liquid chromatography coupled to a tandem mass spectrometry method in two Polish wastewater treatment plants and their receiving surface waters was provided. The highest average concentrations of metronidazole (7400 ng/L), ciprofloxacin (4300 ng/L), vancomycin (3200 ng/L), and sulfamethoxazole (3000 ng/L) were observed in influent of WWTP2. Ciprofloxacin and sulfamethoxazole were the most dominant antimicrobials in influent and effluent of both WWTPs. In the sludge samples the highest mean concentrations were found for ciprofloxacin (up to 28 µg/g) and norfloxacin (up to 5.3 µg/g). The removal efficiency of tested antimicrobials was found to be more than 50% for both WWTPs. However, the presence of antimicrobials influenced their concentrations in the receiving waters. The highest antimicrobial resistance risk was estimated in influent of WWTPs for azithromycin, ciprofloxacin, clarithromycin, metronidazole, and trimethoprim and in the sludge samples for the following antimicrobials: azithromycin, ciprofloxacin, clarithromycin, norfloxacin, trimethoprim, ofloxacin, and tetracycline. The high environmental risk for exposure to azithromycin, clarithromycin, and sulfamethoxazole to both cyanobacteria and eukaryotic species in effluents and/or receiving water was noted. Following the obtained results, we suggest extending the watch list of the Water Framework Directive for Union-wide monitoring with sulfamethoxazole.


Asunto(s)
Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisis , Antiinfecciosos/análisis , Azitromicina/análisis , Cromatografía Liquida , Ciprofloxacina/análisis , Claritromicina/análisis , Aguas del Alcantarillado/química , Sulfametoxazol/análisis , Espectrometría de Masas en Tándem , Eliminación de Residuos Líquidos/métodos
16.
Polymers (Basel) ; 12(1)2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-31963443

RESUMEN

In this paper, we focus on the synthesis and characterization of novel stable nanolayers made of star methacrylate polymers. The effect of nanolayer modification on its antibacterial properties was also studied. A covalent immobilization of star poly(N,N'-dimethylaminoethyl methacrylate) (PDMAEMA) to benzophenone functionalized glass or silicon supports was carried out via a "grafting to" approach using UV irradiation. To date, star polymer UV immobilization has never been used for this purpose. The thickness of the resulting nanolayers increased from 30 to 120 nm with the molar mass of the immobilized stars. The successful bonding of star PDMAEMA to the supports was confirmed by surface sensitive quantitative spectroscopic methods. Next, amino groups in the polymer layer were quaternized with bromoethane, and the influence of this modification on the antibacterial properties of the obtained materials was analyzed using a selected reference strain of bacteria. The resulting star nanolayer surfaces exhibited higher antimicrobial activity against Bacillus subtilis ATCC 6633 compared to that of the linear PDMAEMA analogues grafted onto a support. These promising results and the knowledge about the influence of the topology and modification of PDMAEMA layers on their properties may help in searching for new materials for antimicrobial applications in medicine.

17.
Sci Total Environ ; 711: 134433, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31818597

RESUMEN

Miscanthus x giganteus is a high biomass producing plant with tolerance to heavy metals. This makes Miscanthus interesting to be used for phytoremediation of heavy metal contaminated areas coupled with energy production. Since plant performance in metal polluted areas is impaired, their growth and phytoremediation effect can be improved with bacterial assistance. To identify positive and negative responders of M. x giganteus associated microbiome influenced by Cd, Pb and Zn stress compared to non-contaminated controls, we designed a greenhouse experiment. Structure of the bacterial community in three rhizocompartments, namely rhizosphere, rhizoplane and root endosphere was analysed using an isolation independent molecular approach based on 16S rRNA gene barcoding. Furthermore, quantitative PCR (qPCR) was used for bacterial biomass estimation. Our results indicated that biomass and total bacterial diversity in rhizosphere, rhizoplane and root endosphere did not significantly change despite of substantial root uptake of heavy metals. Overall, we detected 6621 OTUs, from which 171 were affected by metal addition. Whereas Streptomyces and Amycolatopsis taxa were negatively affected by the heavy metal treatment in endosphere, taxa assigned to Luteolibacter in rhizosphere and rhizoplane (log2 fold change 1.9-4.1) and Micromonospora in endosphere (log2 fold change 10.2) were found to be significantly enriched and highly abundant (0.1-3.7% relative abundance) under heavy metal stress. Those taxa might be of key importance for M. x giganteus performance under heavy metal pollution and might be interesting candidates for the development of new bioinocula in the future to promote plant growth and phytoremediation in heavy metal contaminated soils.


Asunto(s)
Microbiota , Biodegradación Ambiental , Metales Pesados , Raíces de Plantas , ARN Ribosómico 16S , Rizosfera , Suelo , Contaminantes del Suelo
18.
Curr Microbiol ; 76(11): 1320-1329, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31432210

RESUMEN

Pseudomonas putida E41 isolated from root interior of Sida hermaphrodita (grown on a field contaminated with heavy metals) showed high biosurfactant activity. In this paper, we describe data from mass spectrometry and genome analysis, to improve our understanding on the phenotypic properties of the strain. Supernatant derived from P. putida E41 liquid culture exhibited a strong decrease in the surface tension accompanied by the ability for emulsion stabilization. We identified extracellular lipopeptides, putisolvin I and II expression but did not detect rhamnolipids. Their presence was confirmed by matrix-assisted laser desorption and ionization (MALDI) TOF/TOF technique. Moreover, ten phospholipids (mainly phosphatidylethanolamines PE 33:1 and PE 32:1) which were excreted by vesicles were also detected. In contrast the bacterial cell pellet was dominated by phosphatidylglycerols (PGs), which were almost absent in the supernatant. It seems that the composition of extracellular (secreted to the environment) and cellular lipids in this strain differs. Long-read sequencing and complete genome reconstruction allowed the identification of a complete putisolvin biosynthesis pathway. In the genome of P. putida E41 were also found all genes involved in glycerophospholipid biosynthesis, and they are likely responsible for the production of detected phospholipids. Overall this is the first report describing the expression of extracellular lipopeptides (identified as putisolvins) and phospholipids by a P. putida strain, which might be explained by the need to adapt to the highly contaminated environment.


Asunto(s)
Metales Pesados/metabolismo , Pseudomonas putida/metabolismo , Sida (Planta)/crecimiento & desarrollo , Contaminantes del Suelo/metabolismo , Tensoactivos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Genoma Bacteriano , Fosfolípidos/química , Fosfolípidos/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Pseudomonas putida/química , Pseudomonas putida/genética , Pseudomonas putida/aislamiento & purificación , Sida (Planta)/metabolismo , Sida (Planta)/microbiología , Microbiología del Suelo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
19.
Colloids Surf B Biointerfaces ; 174: 145-152, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30448711

RESUMEN

Observing flora and fauna, it can be said that nature is a great architect. Nature can create amazing structures with unique properties that may find potential applications in industry. This phenomenon is why the biomimetic synthesis of calcium carbonate with various polymorphs, sizes and morphologies using natural biomolecules, such as proteins and polysaccharides, has become an interesting topic in recent years. This novel work uses natural surfactants produced by Bacillus species (surfactins) in the formation of calcium carbonate particles. Calcium carbonate was synthesized by the reaction of Na2CO3 and CaCl2. The effects of surfactin concentration and pH on calcium carbonate crystal growth were investigated. Precipitated calcium carbonate was characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The pore size and specific surface area were measured via the BET isotherm method. Surfactin molecules were observed to prevent the transformation of vaterite into calcite in the reaction system, especially at pH 8. Surfactin possesses two negatively charged groups (COO-), which have strong affinity towards metal ions at pH 8. When the surfactin concentration was 20 ppm, the surfaces of calcite crystals were punctuated by spherical and oval depressions. Surface roughness may substantially improve the properties of the obtained structures, for example, as inorganic templates for polymeric capsules.


Asunto(s)
Carbonato de Calcio/química , Cristalización , Lipopéptidos/química , Péptidos Cíclicos/química , Bacillus/metabolismo , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
20.
Curr Microbiol ; 75(5): 639-649, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29353420

RESUMEN

The aim of the present study was to determine some properties of antibiotic-resistant bacterial strains isolated from onsite wastewater technology in relation to biofilm formation, e.g., autoaggregation and motility. Additionally, biosurfactant production by the isolates was also evaluated. The ability of selected strains to develop a biofilm was assessed by using the crystal violet method, which allows to indirectly quantify the attached bacterial biomass (live, dead cells, and polysaccharides as well). Obtained results showed that 19 of the analyzed strains were able to produce biofilm after 72 h of incubation. The low values of surface tension in the range between 28 and 36 mN/m were observed in the bacteria, which are not able to produce biofilm or be classified as weak biofilm producers. Among biofilm-forming strains the highest autoaggregation index was observed for Mycobacterium brumae and Bacillus alcalophilus. Noteworthy, that some strains capable of biofilm formation showed no aggregation abilities or were characterized by low autoaggregative properties. The results of visual autoaggregation assay showed no visible flocs after given time of incubation. The results from motility test demonstrated that most of the analyzed strains were motile. Noteworthy, that up to now literature data about physiology, biofilm formation, and autoaggregative capabilities of bacteria isolated from onsite wastewater technology are very limited and this paper gives the information on the antibiotic-resistant bacteria with ability to form biofilm. Thus, the present study points to develop novel bioinocula in antibiotic degradation and to reach novel biofilm-dispersing agents produced by various bacteria that can be used as disinfectants or surface-coating agents to prevent microbial surface colonization and biofilm development.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Biopelículas , Aguas Residuales/microbiología , Purificación del Agua/instrumentación , Bacterias/clasificación , Fenómenos Fisiológicos Bacterianos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...