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1.
Ecotoxicol Environ Saf ; 208: 111621, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396141

RESUMO

The study explored the polycyclic aromatic hydrocarbon tolerance of indigenous biosurfactant producing microorganisms. Three bacterial species were isolated from crude oil contaminated sites of Haldia, West Bengal. The three species were screened for biosurfactant production and identified by 16S rRNA sequencing as Brevundimonas sp. IITISM 11, Pseudomonas sp. IITISM 19 and Pseudomonas sp. IITISM 24. The strains showed emulsification activities of 51%, 57% and 63%, respectively. The purified biosurfactants were characterised using FT-IR, GC-MS and NMR spectroscopy and found to have structural similarities to glycolipopeptides, cyclic lipopeptides and glycolipids. The biosurfactants produced were found to be stable under a wide range of temperature (0-100 °C), pH (4-12) and salinity (up to 20% NaCl). Moreover, the strains displayed tolerance to high concentrations (275 mg/L) of anthracene and fluorene and showed a good amount of cell surface hydrophobicity with different hydrocarbons. The study reports the production and characterisation of biosurfactant by Brevundimonas sp. for the first time. Additionally, the kinetic parameters of the bacterial strains grown on up to 300 mg/L concentration of anthracene and fluorene, ranged between 0.0131 and 0.0156 µmax (h-1), while the Ks(mg/L) ranged between 59.28 and 102.66 for Monod's Model. For Haldane-Andrew's model, µmax (h-1) varied between 0.0168 and 0.0198. The inhibition constant was highest for Pseudomonas sp. IITISM 19 on anthracene and Brevundimonas sp. IITISM 11 on fluorene. The findings of the study suggest that indigenous biosurfactant producing strains have tolerance to high PAH concentrations and can be exploited for bioremediation purposes.


Assuntos
Antracenos/metabolismo , Biodegradação Ambiental , Fluorenos/metabolismo , Tensoativos/metabolismo , Antracenos/química , Bactérias/metabolismo , Fluorenos/química , Glicolipídeos , Hidrocarbonetos/metabolismo , Cinética , Petróleo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pseudomonas/metabolismo , RNA Ribossômico 16S/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química
2.
Chemosphere ; 249: 126097, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32078851

RESUMO

Benz(a)anthracene (BaA) is a polycyclic aromatic hydrocarbons (PAHs), that belongs to a group of carcinogenic and mutagenic persistent organic pollutants found in a variety of ecological habitats. In this study, the efficient biodegradation of BaA by a green alga Chlamydomonas reinhardtii (C. reinhardtii) CC-503 was investigated. The results showed that the growth of C. reinhardtii was hardly affected with an initial concentration of 10 mg/L, but was inhibited significantly under higher concentrations of BaA (>30 mg/L) (p < 0.05). We demonstrated that the relatively high concentration of 10 mg/L BaA was degraded completely in 11 days, which indicated that C. reinhardtii had an efficient degradation system. During the degradation, the intermediate metabolites were determined to be isomeric phenanthrene or anthracene, 2,6-diisopropylnaphthalene, 1,3-diisopropylnaphthalene, 1,7-diisopropylnaphthalene, and cyclohexanol. The enzymes involved in the degradation included the homogentisate 1,2-dioxygenase (HGD), the carboxymethylenebutenolidase, the ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and the ubiquinol oxidase. The respective genes encoding these proteins were significantly up-regulated ranging from 3.17 fold to 13.03 fold and the activity of enzymes, such as HGD and Rubisco, was significantly induced up to 4.53 and 1.46 fold (p < 0.05), during the BaA metabolism. This efficient degradation ability suggests that the green alga C. reinhardtii CC-503 may be a sustainable candidate for PAHs remediation.


Assuntos
Antracenos/metabolismo , Biodegradação Ambiental , Chlamydomonas reinhardtii/metabolismo , Poluentes Ambientais/metabolismo , Benzo(a)Antracenos/metabolismo , Carcinógenos/metabolismo , Dioxigenases/metabolismo , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
3.
Antonie Van Leeuwenhoek ; 113(2): 279-291, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31584108

RESUMO

Halophytic plants growing in harsh desert environments are rich reservoirs of unique endophytic microorganisms. Here, healthy fresh plants of the families Tamaricaceae and Amarantaceae at three saline locations in Iran were investigated for their bioactive endophytic fungi. Among a vast number of isolates, eight isolates were identified as Humicola fuscoatra (Sordariomycetes, Pezizomycotina, Ascomycota) by microscopy and representative DNA sequences of the 5.8S rDNA (ITS) and partial ß-tubulin (TUB2). Those isolates were halotolerant, and highly bioactive, so that their intra- and extra-cellular metabolites possessed in vitro antifungal, antibacterial and antiproliferative activities, against a number of fungal and bacterial plant pathogens including the fungi Arthrobotrys conoides, Pyrenophora graminea, Pyricularia grisea and the bacteria Agrobacterium tumefaciens, Pseudomonas syringae and Xanthomonas oryzae. Chemical analyses of metabolites from the endophytes using HNMR, CNMR, NOESY, COSY, HMBC, HSQC, DEPT, TOCSY and EI MASS techniques identified 3,8-dihydroxy-1-methyl-9,10-anthracenedione (aloesaponarin II; an anthraquinone derivative), 1,8,9-anthracenetriol structure (chrysarobin; an anthranol derivative) and 2,4-di-tert-butylthiophenol in fungal extracts. To the best of our knowledge, this is the first report of endophytic association of halotolerant H. fuscoatra isolates with Tamaricaceae and Amarantaceae, and their bioactivity against plant pathogens. Also, the capability of chrysarobin and aloesaponarin II production is new to the fungal kingdom. These findings may find application in agriculture, pharmacology, and biotechnology.


Assuntos
Amaranthaceae/metabolismo , Ascomicetos/metabolismo , Tamaricaceae/microbiologia , Amaranthaceae/genética , Amaranthaceae/fisiologia , Antracenos/metabolismo , Antralina/metabolismo , Antraquinonas/metabolismo , Ascomicetos/genética , Ascomicetos/fisiologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Plantas Tolerantes a Sal/metabolismo , Plantas Tolerantes a Sal/microbiologia , Tamaricaceae/metabolismo
4.
Ecotoxicol Environ Saf ; 183: 109567, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31442802

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are universal organic pollutants in the agro ecosystems in China, therefore, it is important to understand the uptake and accumulation of PAHs in crops growing on PAHs contaminated soils for human health risk assessments. Water management is a common practice to maintain high grain yields during wheat production. However, the effects of soil water content on the accumulation and translocation of PAHs in wheat are still not clear. The main objectives of the present study were to investigate the effects of soil water content on the accumulation of three selected PAHs (Σ3PAHs, phenanthrene, anthracene and pyrene) in wheat during whole plant growth stage and on translocation or remobilization of Σ3PAHs from vegetative tissues to wheat grains. Winter wheat (Triticum aestivum cv. Xiaoyan22) were grown on Σ3PAHs spiked soils maintaining 80%, 60% or 40% water-holding capacity during the whole plant growth stage. Plant samplings were performed at jointing, anthesis or maturity stage, respectively. The present study showed that grain yield and biomass of the crop increased with soil water content increasing. Transpiration rate of wheat leaf under 80% and 60% water-holding capacity treatments was significantly (p < 0.05) higher than that under 40% water-holding capacity treatment at both anthesis and filling stage. Soil water content and plant growth stage had significant (p < 0.0001) effects on concentrations of phenanthrene, anthracene and pyrene in winter wheat. When exposed to 0, 15, 60, and 150 mg kg-1 Σ3PAHs in soils, Σ3PAHs concentrations in the grains under 60% water-holding capacity treatment were 46.6%, 69.9%, 89.5% and 81.7% of those under 80% water-holding capacity treatment, respectively. The highest concentrations of Σ3PAHs in the crop were recorded at anthesis stage. The distribution of PAHs in different tissues of wheat varied among different soil water treatments and plant growth stages. The present study indicated that optimizing soil water content during winter wheat production could apparently reduce concentrations of Σ3PAHs in grains via influence root uptake of Σ3PAHs and translocation of Σ3PAHs from stem or leaf into grain, suggesting the potential of water management to cope with PAHs contamination in crops growing on PAHs contaminated soils.


Assuntos
Antracenos/análise , Fenantrenos/análise , Pirenos/análise , Solo/química , Triticum/química , Água/análise , Antracenos/metabolismo , Transporte Biológico , Biomassa , China , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Fenantrenos/metabolismo , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Pirenos/metabolismo , Estações do Ano , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Água/metabolismo
5.
Food Chem ; 297: 124977, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253260

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are primarily produced during the incomplete combustion of organic matter. PAHs are suspected endocrine disruptors and possible carcinogenic materials. The major sources of human exposure to PAHs are inhaled fumes and food. The aim of this study was to provide an alternative drying method to mitigate PAH formation in dried red peppers. We prepared dried red pepper samples using air-drying and heat pump-assisted drying methods, and measured the concentrations of four PAHs (PAH4), benzo[a] anthracene (B[a]A), chrysene (CHR), benzo[b]fluoranthene (B[b]F), and benzo[a]pyrene (B[a]P), in the resulting pepper samples. The PAH concentrations ranged from 3.61 to 18.0 µg/kg and from 2.22 to 8.35 µg/kg in the air-dried and heat pump-dried pepper samples, respectively. Overall, the results have shown that dried peppers contain PAH4, that the drying conditions for these contaminants should be optimized for mitigating the PAH formation in dried red peppers.


Assuntos
Capsicum/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Antracenos/análise , Antracenos/metabolismo , Benzo(a)pireno/análise , Benzo(a)pireno/metabolismo , Carcinógenos/análise , Carcinógenos/metabolismo , Crisenos/análise , Crisenos/metabolismo , Dessecação , Fluorenos/análise , Fluorenos/metabolismo , Temperatura Alta , Hidrocarbonetos Policíclicos Aromáticos/análise
6.
Metabolomics ; 15(5): 80, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31087208

RESUMO

INTRODUCTION: The demand to develop efficient and reliable analytical methods for the quality control of nutraceuticals is on the rise, together with an increase in the legal requirements for safe and consistent levels of its active principles. OBJECTIVE: To establish a reliable model for the quality control of widely used Senna preparations used as laxatives and assess its phyto-equivalency. METHODS: A comparative metabolomics approach via NMR and MS analyses was employed for the comprehensive measurement of metabolites and analyzed using chemometrics. RESULTS: Under optimized conditions, 30 metabolites were simultaneously identified and quantified including anthraquinones, bianthrones, acetophenones, flavonoid conjugates, naphthalenes, phenolics, and fatty acids. Principal component analysis (PCA) was used to define relative metabolite differences among Senna preparations. Furthermore, quantitative 1H NMR (qHNMR) was employed to assess absolute metabolites levels in preparations. Results revealed that 6-hydroxy musizin or tinnevellin were correlated with active metabolites levels, suggesting the use of either of these naphthalene glycosides as markers for official Senna drugs authentication. CONCLUSION: This study provides the first comparative metabolomics approach utilizing NMR and UPLC-MS to reveal for secondary metabolite compositional differences in Senna preparations that could readily be applied as a reliable quality control model for its analysis.


Assuntos
Metabolômica , Senosídeos/metabolismo , Acetofenonas/metabolismo , Antracenos/metabolismo , Antraquinonas/metabolismo , Flavonoides/metabolismo , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Naftalenos/metabolismo , Fenóis/metabolismo , Análise de Componente Principal , Controle de Qualidade , Senosídeos/química
7.
Angew Chem Int Ed Engl ; 58(29): 9912-9916, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31119851

RESUMO

There is a growing interest in materials that can dynamically change their properties in the presence of cells to study mechanobiology. Herein, we exploit the 365 nm light mediated [4+4] photodimerization of anthracene groups to develop cytocompatible PEG-based hydrogels with tailorable initial moduli that can be further stiffened. A hydrogel formulation that can stiffen from 10 to 50 kPa, corresponding to the stiffness of a healthy and fibrotic heart, respectively, was prepared. This system was used to monitor the stiffness-dependent localization of NFAT, a downstream target of intracellular calcium signaling using a reporter in live cardiac fibroblasts (CFbs). NFAT translocates to the nucleus of CFbs on stiffening hydrogels within 6 h, whereas it remains cytoplasmic when the CFbs are cultured on either 10 or 50 kPa static hydrogels. This finding demonstrates how dynamic changes in the mechanical properties of a material can reveal the kinetics of mechanoresponsive cell signaling pathways that may otherwise be missed in cells cultured on static substrates.


Assuntos
Antracenos/metabolismo , Biofísica/métodos , Matriz Extracelular/metabolismo , Hidrogéis/química , Polietilenoglicóis/química , Humanos
8.
Colloids Surf B Biointerfaces ; 179: 180-189, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30959230

RESUMO

Fluorophores are used for sensing biologically relevant ions, toxic metals or pathogenic markers. However, the mode of entry of such fluorophores into the cell greatly depends on their size, shape, surface charge, functional groups, and hydrophobicity. In particular, the influence of hydrophobicity on the intracellular uptake of fluorophores is poorly investigated. Self-assembly is a recent strategy to tune the intracellular uptake of fluorophores, facilitating increased intracellular sensing and fluorescence. Herein, self-assembly of three novel poly(aryl ether) dendron derivatives that contain rhodamine units was used to investigate the effect of hydrophobicity on the intracellular uptake of self-assembled fluorophores. The results suggest that monomer hydrophobicity plays an important role in the uptake. The dendron-based fluorophores, which upon self-assembly, formed stable spherical aggregates ranging from 300 to 500 nm. The rhodamine-based dendrons could selectively sense Hg2+ ions in the presence of other competing metal cations. Intracellular imaging of the dendron-based fluorophores displayed bright red fluorescence in human embryonic kidney cells. The rate of intracellular uptake of the three dendron-based fluorophores was analyzed by flow cytometry. The results establish the importance of the hydrophilic-lipophilic balance of the self-assembled amphiphiles for tuning the intracellular uptake.


Assuntos
Antracenos/metabolismo , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Espaço Intracelular/metabolismo , Metais/análise , Sobrevivência Celular , Endocitose , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Células HEK293 , Humanos , Íons , Mercúrio/análise , Espectrometria de Fluorescência
9.
Metab Eng ; 54: 212-221, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31028901

RESUMO

The anthraquinones endocrocin and emodin are synthesized by a special class of type I NR-PKSs and a discrete MßL-TE. In this work, we first reconstituted a biosynthetic pathway of endocrocin and emodin in S. cerevisiae by combining enzymes from different sources. We functionally characterized a TE-less NR-PKS (SlACAS) and a MßL-TE (SlTE) from S. lycopersici as well as four orthologous MßL-TEs. SlACAS was coexpressed with different MßL-TEs in S. cerevisiae. SlACAS generated the highest amount of endocrocin when coupled with HyTE, the yield was 115.6% higher than that with the native SlTE. To accumulate more emodin, seven decarboxylases with high homology to HyDC were identified and introduced into the biosynthetic pathway. Among these orthologs, AfDC exhibited the highest catalytic activity and the conversion rate reached 98.6%. A double-point mutant acetyl-CoA carboxylase, ACC1S659A, S1157A, was further introduced to increase the production of malonyl-CoA as a precursor of these anthraquinones. The production of endocrocin (233.6 ±â€¯20.3 mg/L) and emodin (253.2 ±â€¯21.7 mg/L) then dramatically increased. We also optimized the carbon source in the medium and conducted fed-batch fermentation with the engineered strains. The titers of endocrocin and emodin obtained were 661.2 ±â€¯50.5 mg/L and 528.4 ±â€¯62.7 mg/L, respectively, which are higher than previously reported. In this work, by screening a small library of orthologous biosynthetic bricks, an efficient biosynthetic pathway of endocrocin and emodin was first created in S. cerevisiae. This study provides a novel metabolic engineering approach for optimization of the production of desired molecules.


Assuntos
Emodina/metabolismo , Engenharia Metabólica , Microrganismos Geneticamente Modificados , Saccharomyces cerevisiae , Antracenos/metabolismo , Técnicas de Cultura Celular por Lotes , Microrganismos Geneticamente Modificados/genética , Microrganismos Geneticamente Modificados/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
10.
Analyst ; 144(8): 2696-2703, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30860221

RESUMO

A urea derivative L1 exhibits Aggregation-Induced Emission (AIE) activity in an acetonitrile-water mixed solvent. The aggregation phenomenon has been corroborated by microscopy and light scattering studies. The ligand (L1) also displays a selective turn-on fluorescence response towards human serum albumin (HSA) in 100% aqueous medium over various other comparable proteins (even bovine serum albumin (BSA)) and enzymes. The weakly emissive probe L1 showed a substantial increase in emission intensity upon binding with HSA through electrostatic interactions. The good linear relationship between the fluorescence enhancement (I/I0 - 1) and the concentration of HSA provided the scope to attain an impressive detection limit as low as 5 µg mL-1. A drug displacement experiment and molecular docking study were employed to ascertain the likely protein (HSA)-ligand binding interactions.


Assuntos
Corantes Fluorescentes/química , Albumina Sérica Humana/urina , Ureia/análogos & derivados , Antracenos/síntese química , Antracenos/química , Antracenos/metabolismo , Sítios de Ligação , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/metabolismo , Humanos , Limite de Detecção , Simulação de Acoplamento Molecular , Naftalenos/síntese química , Naftalenos/química , Naftalenos/metabolismo , Ligação Proteica , Albumina Sérica Humana/química , Albumina Sérica Humana/metabolismo , Espectrometria de Fluorescência/métodos , Ureia/síntese química , Ureia/metabolismo
11.
Environ Sci Pollut Res Int ; 26(9): 8675-8684, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30706277

RESUMO

Laccases produced by Leucoagaricus gongylophorus act in lignocellulose degradation and detoxification processes. Therefore, the use of L. gongylophorus laccase (Lac1Lg) was proposed in this work for degradation of anthracene and others polycyclic aromatic hydrocarbons without the use of mediators. Degradation reactions were performed in buffer aqueous solution with 10 ppm of anthracene and other PAHs, Tween-20 in 0.25% v/v and a laccase preparation of 50 U. The optimum condition (pH 6.0 and 30 °C) was determined by response surface methodology with an excellent coefficient of determination (R2) of 0.97 and an adjusted coefficient of determination (R2adj) of 0.93. In addition, the employment of the mediator ABTS decreased the anthracene biodegradation from 44 ± 1% to 30 ± 1%. This optimum pH of 6.0 suggests that the reaction occurs by a hydrogen atom transfer mechanism. Additionally, in 24 h Lac1Lg biodegraded 72 ± 1% anthracene, 40 ± 3% fluorene and 25 ± 3% phenanthrene. The yellow laccase from L. gongylophorus biodegraded anthracene and produced anthrone and anthraquinone, which are interesting compounds for industrial applications. Moreover, this enzyme also biodegraded the PAHs phenanthrene and fluorene justifying the study of Lac1Lg for bioremediation of these compounds in the environment.


Assuntos
Agaricales/metabolismo , Antracenos/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Lacase/metabolismo , Antraquinonas , Fluorenos , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo
12.
AAPS PharmSciTech ; 20(1): 18, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30603884

RESUMO

Nowadays, chemoprevention by administering natural supplements is considered an attractive strategy to reverse, suppress, or prevent the evolution of premalignant oral lesions. In particular, Barbaloin exhibits anti-proliferative, anti-inflammatory, and anti-cancer properties, and it results useful in multi-therapy with classic chemotherapeutics. Therefore, in this work, mucoadhesive buccal films, as locoregional drug delivery system able to provide a targeted and efficient therapeutic delivery of Barbaloin, are proposed. Thus, Aloin extract-loaded Eudragit® RL100 or Eudragit® RS100-based buccal films were designed in order to obtain an easily self-administrable formulation capable of promoting Barbaloin penetration into buccal mucosa and assuring high patient compliance. Large amounts of extract (44%) were loaded into the polymer matrix and six formulations were prepared varying polymers and plasticizers ratios. For all formulations, physical form (thermogravimetric analysis-differential scanning calorimetry, TGA-DSC), swelling degree, mucoadhesiveness, drug release, and ability to promote drug penetration in mucosa have been investigated. After a sequential selection process, Eudragit RS 100-based film, with low PVP and high plasticizers amounts, emerged as the most promising. It results appropriately flexible, uniform in terms of weight, thickness and drug content, as well as characterized by suitable surface pH, good mucoadhesiveness, and low swelling degree. It displays a Higuchian drug release behavior up to 89% of Barbaloin released, thus demonstrating that diffusion through the matrix is the main release mechanism. Remarkable penetration enhancer properties of film were demonstrated by evidence of Barbaloin accumulation into buccal mucosa up to 10-fold higher than those obtained following administration of Aloin solution.


Assuntos
Adesivos/metabolismo , Antracenos/metabolismo , Mucosa Bucal/metabolismo , Polímeros/metabolismo , Resinas Acrílicas/administração & dosagem , Resinas Acrílicas/química , Resinas Acrílicas/metabolismo , Adesivos/administração & dosagem , Administração Bucal , Animais , Antracenos/administração & dosagem , Antracenos/química , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Quimioprevenção/métodos , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Mucosa Bucal/efeitos dos fármacos , Polímeros/administração & dosagem , Polímeros/química , Suínos
13.
J Microbiol Biotechnol ; 29(1): 79-90, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30518016

RESUMO

Lichens are generally known as self-sufficient, symbiotic life-forms between fungi and algae/cyanobacteria, and they also provide shelter for a wide range of beneficial bacteria. Currently, bacterial-derived biodegradable polyhydroxyalkanoate (PHA) is grabbing the attention of many researchers as a promising alternative to non-degradable plastics. This study was conducted to develop a new method of PHA production using unexplored lichen-associated bacteria, which can simultaneously degrade two ubiquitous industrial toxins, anthracene and naphthalene. Here, 49 lichen-associated bacteria were isolated and tested for PHA synthesis. During the GC-MS analysis, a potential strain of EL19 was found to be a 3-hydroxyhexanoate (3-HHx) accumulator and identified as Pseudomonas sp. based on the 16S rRNA sequencing. GC analysis revealed that EL19 was capable of accumulating 30.62% and 19.63% of 3-HHx from naphthalene and anthracene, respectively, resulting in significant degradation of 98% and 96% of naphthalene and anthracene, respectively, within seven days. Moreover, the highly expressed phaC gene verified the genetic basis of PHAmcl production under nitrogen starvation conditions. Thus, this study strongly supports the hypothesis that lichen-associated bacteria can detoxify naphthalene and anthracene, store energy for extreme conditions, and probably help the associated lichen to live in extreme conditions. So far, this is the first investigation of lichen-associated bacteria that might utilize harmful toxins as feasible supplements and convert anthracene and naphthalene into eco-friendly 3-HHx. Implementation of the developed method would reduce the production cost of PHAmcl while removing harmful waste products from the environment.


Assuntos
Antracenos/metabolismo , Líquens/microbiologia , Naftalenos/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Pseudomonas/metabolismo , Aciltransferases/genética , Biodegradação Ambiental , Caproatos/metabolismo , Meios de Cultura/química , Expressão Gênica , Nitrogênio , Filogenia , Poli-Hidroxialcanoatos/metabolismo , Pseudomonas/classificação , Pseudomonas/genética , Pseudomonas/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
14.
Artigo em Inglês | MEDLINE | ID: mdl-30445288

RESUMO

Anthraquinones and anthrones are the main active components of rhubarb. To investigate the metabolism and possible mutual biotransformations pathways of anthraquinones and anthrones by human intestinal flora, 9 representative constituents (aloe-emodin, rhein, emodin, chrysophanol, physcion, sennosides A, B, C and D) were studied. An ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) with mass spectrometryElevated Energy (MSE) technology was employed to separate and identify their metabolites. As a result, a total of 64 metabolites were identified or characterized from 9 components. Among them, 12 of them were identified by compared with the reference substances, 52 of them were tentatively identified. The results indicated that reduction, hydrolysis, acetylation, oxidation, demethylation, methylation, hydroxylation, dehydroxylation and the bond cleavage of CO and CC were likely to be the metabolic pathways involved in the generation of these metabolites. Moreover, mutual biotransformations existed among the nine representative constituents in rhubarb by human intestinal flora. This study will provide evidences that intestinal flora may play an important role in mediating the bioactivities in vivo of anthraquinones and anthrones in rhubarb.


Assuntos
Antracenos/metabolismo , Antracenos/farmacocinética , Antraquinonas/metabolismo , Antraquinonas/farmacocinética , Microbioma Gastrointestinal/fisiologia , Rheum/química , Antracenos/química , Antraquinonas/química , Fenômenos Bioquímicos , Biotransformação , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Espectrometria de Massas em Tandem/métodos
15.
Chemosphere ; 215: 746-752, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30352372

RESUMO

Understanding the alteration of the air-liquid interfacial properties of pulmonary surfactant (PS) in the presence of nanoparticles (NPs) and polycyclic aromatic hydrocarbons (PAHs) is particularly important for pulmonary risk assessment. Here, we investigated the interaction of natural PS (extracted from pig's lungs) with nano carbon particles (NCPs) and anthracene as a representative PAH. Our results showed that PS exhibited a significant solubilization effect on anthracene. Solubilization experiment for the substructures of PS demonstrated that the mixed phospholipid components of PS played the primary role in the solubilization of PS for anthracene. Adsorption experiment indicated that in the mixed system of PS, NCPs, and anthracene, PS can inhibit the adsorption of anthracene on NCPs due to the solubilization, agglomeration, and competitive adsorption. In addition, the surface tension, phase behavior, and foaming ability of PS were obviously altered in the presence of NCPs. These findings indicate that the solubilization effect of PS on anthracene, the inhibitive effect of PS for the adsorption of anthracene on NCPs, and the alternation of air-liquid interfacial properties of PS containing NCPs may increase the pulmonary risk in the exposure of atmospheric environment containing both PAHs and NCPs.


Assuntos
Antracenos/metabolismo , Carbono/metabolismo , Nanopartículas/metabolismo , Surfactantes Pulmonares/metabolismo , Adsorção , Animais , Carbono/toxicidade , Exposição por Inalação , Micelas , Nanopartículas/toxicidade , Suínos , Testes de Toxicidade
16.
J Mol Microbiol Biotechnol ; 28(4): 183-189, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30566957

RESUMO

Nowadays, contamination of soil and marine sediments by polycyclic aromatic hydrocarbons (PAHs) has become a serious problem all over the world. Rhodococcus sp. P14 was isolated from sediments with crude oil contaminate and showed degradation ability on various PAHs. The genome of Rhodococcus sp. P14 was sequenced. A gene cluster encoding a ring-hydroxylating dioxygenase Baa related to PAH degradation was identified by bioinformatics. The expression level of gene baaA was increased when P14 was cultured with anthracene, pyrene, phenanthrene, or benz[a]-anthracene as the single carbon source. The recombinant protein Baa was overexpressed in E. coli BL21 (DE3). Further investigations on the recombinant protein Baa in E. coli demonstrated that it was able to oxidize anthracene and benz [a]anthracene, resulting in 9,10-dihydroxyanthracene and 7, 12-dihydroxybenz[a]anthracene as metabolites, respectively. These results indicate that Baa plays an important role in PAH degradation in Rhodococcus sp. P14 and Baa has potential application in the bioremediation of PAHs in the contaminated environment.


Assuntos
Antracenos/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Rhodococcus/genética , Rhodococcus/metabolismo , Sequência de Bases , Biodegradação Ambiental , Dioxigenases/classificação , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Sedimentos Geológicos/microbiologia , Hidroxilação , Família Multigênica , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pirenos , Proteínas Recombinantes/genética , Alinhamento de Sequência
17.
Sci Rep ; 8(1): 14844, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30287882

RESUMO

Engineered odorant-binding proteins (OBPs) display tunable binding affinities triggered by temperature alterations. We designed and produced two engineered proteins based on OBP-I sequence: truncated OBP (tOBP) and OBP::GQ20::SP-DS3. The binding affinity of 1-aminoanthracene (1-AMA) to these proteins revealed that tOBP presents higher affinity at 25 °C (kd = 0.45 µM) than at 37 °C (kd = 1.72 µM). OBP::GQ20::SP-DS3 showed an opposite behavior, revealing higher affinity at 37 °C (kd = 0.58 µM) than at 25 °C (kd = 1.17 µM). We set-up a system containing both proteins to evaluate their temperature-dependent binding. Our data proved the 1-AMA differential and reversible affinity towards OBPs, triggered by temperature changes. The variations of the binding pocket size with temperature, confirmed by molecular modelling studies, were determinant for the differential binding of the engineered OBPs. Herein we described for the first time a competitive temperature-dependent mechanism for this class of proteins.


Assuntos
Antracenos/metabolismo , Receptores Odorantes/metabolismo , Temperatura , Sequência de Aminoácidos , Aminoácidos , Animais , Sítios de Ligação , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Engenharia de Proteínas , Receptores Odorantes/química , Receptores Odorantes/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Análise Espectral , Relação Estrutura-Atividade , Suínos
18.
Biophys Chem ; 242: 1-5, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30153504

RESUMO

The binding and photochirogenic behaviour of 2-anthracenecarboxylate (AC) with human serum albumin (HSA) have hitherto been investigated and comprehended as time-averaged statistical events by spectroscopic examinations and product analyses. In this study, we employed a diffracted X-ray tracking (DXT) technique to visualize the single-molecular dynamics of free and AC-loaded HSA (AC:HSA = 0, 1, 5 and 10), as well as the AC-HSA complex under photoirradiation, all of which were tethered to gold nanocrystals and hence traceable in real time by DXT. This enabled us to draw a more dynamic picture of the bio-supramolecular photochirogenesis at a single-molecule resolution, detailing the softening and flexibility enhancement of HSA upon binding of ACs to its inter-subdomain IIA-IIB site and the dynamic extrusion of AC dimers produced upon photoirradiation.


Assuntos
Antracenos/química , Ácidos Carboxílicos/química , Antracenos/metabolismo , Ácidos Carboxílicos/metabolismo , Dimerização , Ouro/química , Humanos , Lasers de Estado Sólido , Nanopartículas Metálicas/química , Ligação Proteica , Albumina Sérica/química , Albumina Sérica/metabolismo , Estereoisomerismo , Difração de Raios X
19.
PLoS One ; 13(8): e0201620, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30071070

RESUMO

Biodegradation of hazardous pollutants is of immense importance for maintaining a clean environment. However, the concentration of such contaminants/pollutants can be minimized with the help of microorganisms that has the ability to degrade the toxic pollutants into non-toxic metabolites. In the current study, 23 bacterial isolates were purified from the rhizospheric soil of Sysimbrium irio, growing as a wild plant in the vicinity of gas filling stations in Peshawar city. The isolated strains were initially screened on solid nutrient agar and further purified by culturing it on anthracene amended mineral media (PNR). The bacterial growth and anthracene disappearance were observed by calculating optical density (OD). The isolates showed a concentration-dependent growth on anthracene amended PNR media at 30°C and pH7. Also, an increase in bacterial OD from 0.351 to 1.80 with increased shaking speed was noticed. On the contrary, alternate carbon sources (glucose, fructose, sucrose) or nitrogen sources (KNO3, NaNO3, NH4NO3 and CaNO3) posed inhibitory effect on bacterial growth during anthracene degradation. The recorded efficiency of anthracene degradation by the selected bacterial isolate (1.4×1023 CFUmL-1 and 1.80 OD) was 82.29%, after 120 h of incubation. The anthracene was degraded to 9, 10, dihydroxy-anthracene and anthraquinone, detected through GC-MS. The efficient bacterial isolate was identified as S13, a new strain of Bacillus cereus, using 16S rRNA analysis, showing 98% homology. The isolated bacterial strain S13 may be used as a potential tool for bioremediation of toxic hydrocarbons and to keep the environment free from PAH pollutants.


Assuntos
Antracenos/metabolismo , Bacillus cereus/metabolismo , Antracenos/química , Antraquinonas/análise , Bacillus cereus/classificação , Bacillus cereus/genética , Bacillus cereus/isolamento & purificação , Biodegradação Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Filogenia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Microbiologia do Solo , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Temperatura
20.
World J Microbiol Biotechnol ; 34(9): 133, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30109517

RESUMO

The ability of the litter-decomposing basidiomycete Stropharia rugosoannulata DSM 11372 to degrade a wide range of structurally different environmental pollutants such as polycyclic aromatic hydrocarbons (PAHs: phenanthrene, anthracene, fluorene, pyrene, and fluoranthene), synthetic anthraquinone dyes containing condensed aromatic rings, environmentally relevant alkylphenol and oxyethylated alkylphenol representatives, and oil was demonstrated within the present study. 9,10-Anthraquinone, phenanthrene-9,10-quinone, and 9-fluorenone were identified as products of anthracene, phenanthrene, and fluorene degradation, respectively. Fungal degradation was accompanied by the production of the ligninolytic enzymes: laccase and Mn peroxidase, suggesting their involvement in pollutant degradation. Extracellular polysaccharide(s) (EPS) and emulsifying compound(s) were concomitantly produced. EPS composed of mannose, glucose, and galactose was isolated from the cultivation medium, and its effects on catalytic properties of purified laccase from S. rugosoannulata (the dominating ligninolytic enzyme under the applied conditions) were studied. A simultaneous decrease of KM and Vmax values observed for the enzymatic oxidation of non-phenolic (2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt; ABTS) and phenolic compounds (2,6-dimethoxyphenol) in presence of EPS suggest an interaction of EPS and laccase resulting in a modulation of the catalytic performance of the enzyme, which has, to the best of our knowledge, not been reported before. In line with such a modulation, the laccase-catalyzed oxidation of natural aromatic compounds (veratryl alcohol, adlerol) and environmental pollutants (the alkylphenol representative nonylphenol, the diphenylmethane derivative bisphenol A, and the PAH representative anthracene) was found to be enhanced in presence of EPS. The relevance of such effects for real environmental processes and their implications remain to be investigated.


Assuntos
Adaptação Fisiológica , Agaricales/enzimologia , Agaricales/fisiologia , Biodegradação Ambiental , Poluentes do Solo/metabolismo , Antracenos/metabolismo , Compostos Benzidrílicos/metabolismo , Biotransformação , Poluentes Ambientais , Fluorenos/metabolismo , Hidrocarbonetos Cíclicos/metabolismo , Lacase/metabolismo , Oxirredução , Peroxidases/metabolismo , Fenantrenos/metabolismo , Fenóis/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pirenos/metabolismo
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