Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.003
Filtrar
1.
Sci Total Environ ; 804: 150153, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509835

RESUMO

Pyrene, a typical four-ring polycyclic aromatic hydrocarbon, is abundantly present in the environment and is potentially harmful to the human body. In this study, single-chamber air-cathode microbial fuel cells (MFCs) were used to treat pyrene, and the ensuing degradation, electrical parameters, and microbial changes were analyzed. The results showed that MFCs could degrade pyrene, and the maximum degradation rate for 30 mg/L reached 88.1 ± 5.4%. The addition of pyrene reduced the electrical performance of the MFCs and suppressed the power output. Analysis of the anodic microbial community showed that the proportion of Alcaligenes and Stenotrophomonas increased with an increase in pyrene concentration, which may explain the high degradation rate of pyrene.


Assuntos
Fontes de Energia Bioelétrica , Bactérias , Eletricidade , Eletrodos , Humanos , Pirenos
2.
Chemosphere ; 286(Pt 2): 131787, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34365168

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are important mutagen prevalent in the contaminated sites, bringing potential risks to human health. Iron oxides are important natural components in soils. Pyrene removal in soil using persulfate (PS) oxidation activated by microwave (MW) and magnetite (Fe3O4) was investigated. Fe3O4 significantly promoted pyrene removal in the soil; 91.7 % of pyrene was degraded within 45 min treatment. Pyrene removal rate in the Fe3O4/MW/PS system was 5.18 and 3.00 times higher than that in the Fe3O4/PS and MW/PS systems. Increasing in Fe3O4 dosage, PS concentration, MW temperature, and soil moisture content in the selected range were conducive for pyrene degradation. SO4•-, •OH, O2•-, and 1O2 were responsible for pyrene degradation, and the conversion of Fe (Ⅱ) in the Fe3O4 to Fe (Ⅲ) contributed to the formation of O2•- and 1O2. Characteristic bands of pyrene were more obviously destroyed by the Fe3O4/MW/PS oxidation, in comparison with MW/PS oxidation. Ring hydroxylation and ring-opening reactions were the main degradation pathways of pyrene. The toxicities of the formed byproducts were significantly reduced after treatment. This study provided a promising option for pyrene contaminated soil remediation.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo , Óxido Ferroso-Férrico , Humanos , Micro-Ondas , Pirenos , Solo , Poluentes do Solo/análise
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120228, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34388430

RESUMO

Lysosome is one of the important organelles in intracellular transport. It plays a significant role in the physiological process. The lysosomal microenvironment affects the functions of lysosome. When the original acidic environment of lysozyme is destroyed or the fluid viscosity increases gradually, various diseases are easily induced. However, most fluorescent probes can only locate in cells. The fewer probes of subcellular organelles were found and their functions are often single. So, it is of great importance to design multifunctional fluorescent probes with the capable of localizing in lysosome. In this study, a novel lysosome probe, 4-(4-Pyren-1-yl-but-3-enyl)-morpholine (PIM), was synthesized using pyrene as a fluorescent group and morpholine as a target group. The introduction of morpholine group made PIM localize in lysosome with high selectivity. The fluorescence will be enhanced with the increased viscosity because of restricting the rotation of CC bond and CN in PIM, and the detecting linear range is from 4.05 cP to 393.48 cP, which qualified the requirement of the viscosity monitoring in body. Meanwhile, the fluorescence intensity of PIM declines with the decrease of pH because the Schiff base of PIM is hydrolyzed, which was affirmed by 1H NMR, LC-MS and fluorescence spectra. Moreover, cell imaging and MTT experiments confirmed that PIM as a novel bifunctional probe can be used to detect pH and endogenous viscosity in lysosome.


Assuntos
Corantes Fluorescentes , Lisossomos , Fluorescência , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Pirenos , Viscosidade
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120272, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34428636

RESUMO

Hydrazine, as a toxic substance, seriously endangers human health and the environment. Based on the excellent luminescent properties and low biological toxicity of pyrene derivatives, combing with chalcone derivatives easily attacked by nucleophilic group, a pyrene derivative PCA decorated by acryloyl terminal group as fluorescent probe for hydrazine was developed. The compound shows fluorescent peak red shift and intensity enhancement with increasing solvent polarity from hexane (459 nm) to methanol (561 nm). Based on strong fluorescence emission in methanol, methanol-HEPES mixed solution was used as the solvent in the spectral recognition experiments. The probe exhibits fluorescent change from yellow fluorescence (576 nm) to blue fluorescence (393 nm) with 800-fold ratiometric fluorescence enhancement (I393nm/I576nm) after the reaction with hydrazine. The probe can recognize hydrazine in fast response rate with kinetic constant calculated being 2.7 × 10-3 s-1 and 15 min as response time. The probe also can monitor hydrazine in real water samples and various soils.


Assuntos
Chalcona , Chalconas , Corantes Fluorescentes , Humanos , Hidrazinas , Pirenos , Espectrometria de Fluorescência
5.
Sci Total Environ ; 805: 150324, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818808

RESUMO

Microbial extracellular electron transfer (EET) at microbe-mineral interface has been reported to play a significant role in pollutant biotransformation. Different metals often co-exist with organic pollutants and are immobilized on mineral surfaces. However, little is known about the influence of mineral surface metal ions on organic pollutant biodegradation and the involved electron transfer mechanism. To address this knowledge gap, pyrene was used as a model compound to investigate the biodegradation of polycyclic aromatic hydrocarbon on montmorillonite mineral saturated with metal ions (Na(I), Ni(II), Co(II), Cu(II) and Fe(III)) by Mycobacteria strain NJS-1. Further, the possible underlying electron transfer mechanism by electrochemical approaches was investigated. The results show that pyrene biodegradation on montmorillonite was markedly influenced by surface metal ions, with degradation efficiency following the order Fe(III) > Na(I) ≈ Co(II) > Ni(II) ≈ Cu(II). Bioelectrochemical analysis showed that electron transfer activities (i.e., electron donating capacity and electron transport system activity) varied in different metal-modified montmorillonites and were closely related to pyrene biodegradation. Fe(III) modification greatly stimulated degrading enzyme activities (i.e., peroxidase and dioxygenase) and electron transfer activities resulting in enhanced pyrene biodegradation, which highlights its potential as a technique for pollutant bioremediation. The bacterial extracellular protein and humic substances played important roles in EET processes. Membrane-bound cytochrome C protein and extracellular riboflavin were identified as the electron shuttles responsible for transmembrane and cross extracellular matrix electron transfer, respectively. Additions of exogenetic electron mediators of riboflavin, humic acid and potassium ferricyanide accelerated pyrene biodegradation which further verified the critical role of EET in PAH transformation at bacteria-mineral interfaces. These results support the development of clay mineral based advanced bioremediation techniques through regulating the electron transfer processes at the microbe-mineral interfaces by mineral surface modification.


Assuntos
Bentonita , Hidrocarbonetos Policíclicos Aromáticos , Biodegradação Ambiental , Compostos Férricos , Íons , Pirenos
6.
Ecotoxicol Environ Saf ; 226: 112838, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34607190

RESUMO

Persistent and ubiquitous organic pollutants, such as the polycyclic aromatic hydrocarbon benzo[⍺]pyrene (BaP), represent a major threat to aquatic organisms and human health. Beside some well-documented adverse effects on the development and reproduction of aquatic organisms, BaP was recently shown to affect fish bone formation and skeletal development through mechanisms that remain poorly understood. In this work, zebrafish bone-related in vivo assays were used to evaluate the osteotoxic effects of BaP during bone development and regeneration. Acute exposure of zebrafish larvae to BaP from 3 to 6 days post-fertilization (dpf) induced a dose-dependent reduction of the opercular bone size and a depletion of osteocalcin-positive cells, indicating an effect on osteoblast maturation. Chronic exposure of zebrafish larvae to BaP from 3 to 30 dpf affected the development of the axial skeleton and increased the incidence and severity of skeletal deformities. In young adults, BaP affected the mineralization of newly formed fin rays and scales, and impaired fin ray patterning and scale shape, through mechanisms that involve an imbalanced bone remodeling. Gene expression analyses indicated that BaP induced the activation of xenobiotic and metabolic pathways, while negatively impacting extracellular matrix formation and organization. Interestingly, BaP exposure positively regulated inflammation markers in larvae and increased the recruitment of neutrophils. A direct interaction between neutrophils and bone extracellular matrix or bone forming cells was observed in vivo, suggesting a role for neutrophils in the mechanisms underlying BaP osteotoxicity. Our work provides novel data on the cellular and molecular players involved in BaP osteotoxicity and brings new insights into a possible role for neutrophils in inflammatory bone reduction.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Peixe-Zebra , Animais , Benzo(a)pireno/toxicidade , Humanos , Larva , Pirenos
7.
Ecotoxicol Environ Saf ; 227: 112939, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34717220

RESUMO

Haze problem is an important factor threatening human health. PM2.5 is the main culprit haze. 1-Nitropyrene (1-NP) is the main nitrated polycyclic aromatic hydrocarbon, the toxic component of PM2.5 particles. The effects of 1-NP on various organs and reproductive health have been extensively and deeply studied, but the effects of 1-NP on embryo implantation and endometrial receptivity remain to be determined. The purpose of this study was to investigate the adverse effects of 1-NP on mouse embryo implantation and human endometrial receptivity. In early pregnancy, CD1 mice were given 2 mg/kg 1-NP by oral gavage, which resulted in a decreased embryo implantation number on day 5, inhibited leukemic inhibitory factor (LIF)/STAT3 pathway, decreased expression of estrogen receptor and progesterone receptor, and disrupted regulation of uterine cell proliferation. In addition, in a human in vitro implantation model, 1-NP was found to significantly inhibit the adhesion rate between trophoblast spheroids and endometrial epithelial cells, possibly by inhibiting the expression of receptivity molecules in Ishikawa cells. Promoting reactive oxygen species (ROS) production may be an additional mechanism by which it inhibits trophoblast spheroid adhesion. In this study, we used an in vivo mouse pregnancy model and an in vitro human embryo implantation model to demonstrate that 1-NP can impair endometrial receptivity and compromise embryo implantation.


Assuntos
Implantação do Embrião , Endométrio , Animais , Feminino , Camundongos , Gravidez , Pirenos , Espécies Reativas de Oxigênio , Útero
8.
J Hazard Mater ; 416: 126202, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492965

RESUMO

The present study was conducted to compare the efficiency of different microbial mixed-cultures consists of fifteen oil-degrading microorganisms with different combinations. The investigation was targeted toward the removal of 500 mg/l pyrene and 1% w/v tetracosane, as single compounds or mixture. Sequential Fungal-Bacterial Mixed-Culture (SMC) in which bacteria added one week after fungi, recorded 60.76% and 73.48% degradation for pyrene and tetracosane; about 10% more than Traditional Fungal-Bacterial Mixed-Culture (TMC). Co-degradation of pollutants resulted in 24.65% more pyrene degradation and 6.41% less tetracosane degradation. The non-specified external enzymes of fungi are responsible for initial attacks on hydrocarbons. Delayed addition of bacteria and co-contamination would result in higher growth of fungi which increases pyrene degradation. The addition of Rhamnolipid potently increased the extent of pyrene and tetracosane degradation by approximately 16% and 23% and showed twice better performance than Tween-80 in 20 times less concentration. The results indicated the importance of having sufficient knowledge on the characteristics of the contaminated site and its contaminants as well as oil-degrading species. Gaining this knowledge and using it properly, such as the later addition of bacteria (new method of mixed-cultures inoculation) to the contaminated culture, can serve as a promising approach.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Alcanos , Bactérias , Biodegradação Ambiental , Fungos , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos , Microbiologia do Solo , Poluentes do Solo/análise
9.
ACS Appl Mater Interfaces ; 13(36): 43696-43707, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34470205

RESUMO

Graphene is a two-dimensional semiconducting material whose application for diagnostics has been a real game-changer in terms of sensitivity and response time, variables of paramount importance to stop the COVID-19 spreading. Nevertheless, strategies for the modification of docking recognition and antifouling elements to obtain covalent-like stability without the disruption of the graphene band structure are still needed. In this work, we conducted surface engineering of graphene through heterofunctional supramolecular-covalent scaffolds based on vinylsulfonated-polyamines (PA-VS). In these scaffolds, one side binds graphene through multivalent π-π interactions with pyrene groups, and the other side presents vinylsulfonated pending groups that can be used for covalent binding. The construction of PA-VS scaffolds was demonstrated by spectroscopic ellipsometry, Raman spectroscopy, and contact angle measurements. The covalent binding of -SH, -NH2, or -OH groups was confirmed, and it evidenced great chemical versatility. After field-effect studies, we found that the PA-VS-based scaffolds do not disrupt the semiconducting properties of graphene. Moreover, the scaffolds were covalently modified with poly(ethylene glycol) (PEG), which improved the resistance to nonspecific proteins by almost 7-fold compared to the widely used PEG-monopyrene approach. The attachment of recognition elements to PA-VS was optimized for concanavalin A (ConA), a model lectin with a high affinity to glycans. Lastly, the platform was implemented for the rapid, sensitive, and regenerable recognition of SARS-CoV-2 spike protein and human ferritin in lab-made samples. Those two are the target molecules of major importance for the rapid detection and monitoring of COVID-19-positive patients. For that purpose, monoclonal antibodies (mAbs) were bound to the scaffolds, resulting in a surface coverage of 436 ± 30 ng/cm2. KD affinity constants of 48.4 and 2.54 nM were obtained by surface plasmon resonance (SPR) spectroscopy for SARS-CoV-2 spike protein and human ferritin binding on these supramolecular scaffolds, respectively.


Assuntos
Biomarcadores/análise , COVID-19/diagnóstico , Grafite/química , Imunoensaio/métodos , Glicoproteína da Espícula de Coronavírus/análise , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Etilenos/química , Ferritinas/imunologia , Ferritinas/metabolismo , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Poliaminas/química , Polietilenoglicóis/química , Pirenos/química , Teoria Quântica , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Semicondutores , Glicoproteína da Espícula de Coronavírus/imunologia , Ácidos Sulfônicos/química , Ressonância de Plasmônio de Superfície
10.
J Org Chem ; 86(19): 13360-13370, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34528793

RESUMO

A first and short total synthesis of the marine sponge 2,3'-bis(indolyl)ethylamine (2,3'-BIEA) alkaloid (±)-gelliusine E was performed in both a three-step divergent approach and a one-pot three-component approach with an overall yield of up to 58%. A key feature of the novel strategy is PTSA-catalyzed transindolylation of the readily synthesized 3,3'-BIEAs with tryptamine derivatives. The structure of the isolated natural product is revised as protonated (±)-gelliusine E (4'). By design, this modular route allows the rapid synthesis of other members of the 2,3'-BIEA family, for example, (±)-6,6'-bis-(debromo)-gelliusine F and analogues with step economy, operational simplicity, and reduced waste. Furthermore, their cytotoxicity in breast cancer cells was investigated.


Assuntos
Produtos Biológicos , Poríferos , Animais , Catálise , Etilaminas , Pirenos
11.
Ecotoxicol Environ Saf ; 225: 112789, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560613

RESUMO

A slow degradation rate and low transformation efficiency are the main problems in the biodegradation of polycyclic aromatic hydrocarbons (PAHs). This study selected pyrene as the target PAH to investigate the effect of ferrous ion and ferric ion on pyrene degradation. The driving effect and mechanism, including the interaction between pyrene and iron ions and the bacterial physiological response during the biodegradation process by Rhodococcus ruber strain L9, were investigated. The results showed that iron ions did not enhance bacterial growth but improved bacteria's pyrene removal capacity, contributing to the total efficiency of pyrene biodegradation. The process started with an initial formation of "cation-π" between Fe (III) and pyrene, which subsequently drove the pyrene removal process and accelerated the bacterial metabolic process. Moreover, a significant increase in the protein concentration, catechol dioxygenase (C12O and C23O) activities, and intracellular protein regulation in crude enzyme solution indicate a positive response of the bacteria during the iron ion-enhanced pyrene degradation process.


Assuntos
Ferro , Rhodococcus , Íons , Pirenos
12.
Anal Chim Acta ; 1178: 338807, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482879

RESUMO

In this work, we have designed and synthesized a new fluorescent molecular probe, DPY comprising of pyrene-diacetylpyridine conjugate, which was found to be sensitive to hydrazine as well as protonation. DPY is characterised by a strong emission both in solution (λem = 530 nm) as well as in solid state (λem = 610 nm), attributed to intramolecular charge-transfer. The probe responds to hydrazine with a ratiometric fluorescence emission change from yellow to blue, due to chalcone cyclisation reaction of α, ß-unsaturated carbonyl group resulting in the pyrazoline compound, DPY-Hy, imparting a strong greenish-blue emission in solution. Further, the strong fluorescence emission of DPY in powder and thin film was quenched upon exposure to TFA, and revived upon exposure to TEA. For developing on-site detection protocol, when DPY was drop-casted on nonfluorescent silica plate a vivid naked-eye colour change from orange-red to dark blue was realized. Interestingly, in the aggregated state, DPY exhibited a broad range emission from green to orange in a mixed solvent system of THF:H2O. A plausible explanation of the photophysical events is substantiated with theoretical calculations.


Assuntos
Chalcona , Chalconas , Corantes Fluorescentes , Hidrazinas , Pirenos
13.
Chemistry ; 27(59): 14582-14585, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34472671

RESUMO

Herein is reported a circularly polarized luminescent (CPL) probe that can respond to the chirality of nucleic acids. An achiral nanostructure was prepared by the hybridization of symmetric serinol nucleic acid (SNA) containing pyrene-modified residues. When chiral oligomers that were complementary to the SNA were added, they induced helicity into the SNA nanowire. Efficient circular dichroism (CD) signal amplification was observed when pyrene was attached to uracil bases through a rigid alkynyl linker. Both CPL and CD signals were observed; they depended on the chirality of the added acyclic threoninol nucleic acid (aTNA) oligomer. This system can be used to convert the chirality of chiral biomolecules into chiroptical signals.


Assuntos
Nanoestruturas , Ácidos Nucleicos , Amino Álcoois , Butileno Glicóis , Luminescência , Propanolaminas , Propilenoglicóis , Pirenos
14.
Molecules ; 26(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34443404

RESUMO

Novel dyes were prepared by simple "click CuAAC" attachment of a triarylborane-alkyne to the azide side chain of an amino acid yielding triarylborane dye 1 which was conjugated with pyrene (dye 2) forming a triarylborane-pyrene FRET pair. In contrast to previous cationic triarylboranes, the novel neutral dyes interact only with proteins, while their affinity to DNA/RNA is completely abolished. Both the reference triarylborane amino acid and triarylborane-pyrene conjugate bind to BSA and the hDPP III enzyme with high affinities, exhibiting a strong (up to 100-fold) fluorescence increase, whereby the triarylborane-pyrene conjugate additionally retained FRET upon binding to the protein. Furthermore, the triarylborane dyes, upon binding to the hDPP III enzyme, did not impair its enzymatic activity under a wide range of experimental conditions, thus being the first non-covalent fluorimetric markers for hDPP III, also applicable during enzymatic reactions with hDPP III substrates.


Assuntos
Corantes/química , Cicloexanos/química , Corantes Fluorescentes/química , Fluorometria , Indóis/química , Alcinos/química , Aminoácidos/química , Azidas/química , Pirenos/química
15.
Environ Pollut ; 289: 117936, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34391044

RESUMO

Pyrene (Pyr), a widely used tetracyclic aromatic hydrocarbon, enters soil in large quantities and causes environmental pollution due to its production and mining. In order to systematically study the biotoxicity of pyrene to model organisms Eisenia fetida in soil, experiments were carried out from four dimensions: animal, tissue, cell and molecule. Experimental results proved that the mortality rate increased with increasing concentration and time of exposure to pyrene, while the mean body weight and spawning rate decreased. Meanwhile, when the pyrene concentration reached 900 mg/kg, the seminal vesicle and longitudinal muscle of the earthworm showed obvious atrophy. Experimental results at the cellular level showed that pyrene induced cell membrane damage and Ca2+ influx triggered mitochondrial membrane depolarization and a surge in ROS levels. Oxidative stress causes damage to proteins and lipids and DNA inside cells. When the mortality rate was 91.67 %, the Olive Tail Movement (OTM) of the comet experiment reached 15. The results of molecular level tests showed that pyrene inhibited the activity of Cu/Zn-superoxide dismutase (Cu/Zn-SOD) mainly by changing the microenvironment and secondary structure of amino acid Tyr 108. The weakened function of direct antioxidant enzymes may be the root cause of the excessive increase of reactive oxygen species (ROS) in cells. The systematic approach used in this study enriches the network of toxic pathways in toxicological studies, and basic data on the biological toxicity of pyrene can provide support for future soil contamination detection.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Catalase/metabolismo , Dano ao DNA , Oligoquetos/metabolismo , Estresse Oxidativo , Pirenos/toxicidade , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Superóxido Dismutase/metabolismo
16.
Sci Total Environ ; 800: 149485, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392205

RESUMO

Pyrene is a model contaminant of high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs), which are compounds that have potential carcinogenic effects and pose a serious threat to human health. Finding effective pyrene-degrading bacteria is crucial for removing PAHs from soil. In this study, DNA-based stable isotope probing (DNA-SIP) technology was used to investigate pyrene degraders in PAH-contaminated oilfield soil during natural attenuation (NA), bioaugmentation (BA) and biostimulation (BS). The results show that BA played an important role in pyrene degradation with the highest pyrene removal rate (~95%) after 12 days incubation, followed by removal rates of ~90% for NA and ~30% for BS. In addition, 6 novel pyrene degraders were identified, while 12 well-known PAH degraders were demonstrated to participate in the biodegradation of pyrene. Additionally, the external homologous strains introduced during BA promoted the degradation of pyrene, but not by directly participating in the metabolism of the target compound. Rhamnolipid supplementation during BS promoted the involvement of more microorganisms in the degradation of pyrene, which was beneficial to identifying more pyrene degraders via DNA-SIP. These findings provide new insight into the effects of external homologous strains and supplementary rhamnolipids on pyrene degradation.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , DNA , Humanos , Isótopos , Campos de Petróleo e Gás , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos , Solo , Microbiologia do Solo , Poluentes do Solo/análise
17.
J Photochem Photobiol B ; 223: 112279, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34425416

RESUMO

A novel highly selective and sensitive turn-on fluorescent chemosensor PCE to recognize Zn2+ has been developed. The sensor PCE displays a remarkable fluorescent enhancement at 456 nm (λex = 340 nm) with Zn2+ without the interference of other biologically important relevant metal ions in aqueous acetonitrile solution. Job's plot and mass spectral studies divulge such the interaction of PCE by Zn2+ was 1:1 binding stoichiometry. The association constant and detection limit of PCE to recognize Zn2+ was found to be 0.948 × 104 M-1 and 4.82 × 10-7 M respectively. The nature of turn-on fluorescence sensor was supported by TD-DFT calculations. And the synthesized probe PCE was able to image intracellular Zn2+ in living cells using confocal imaging techniques. PCE-Zn ensemble showed the remarkable fluorescence enhancement with ATP selectively among other biologically important phosphates. 31P NMR experiments suggesting that the triphosphates unit of ATP is intact with the PCEZn. PCE-Zn ensemble can be utilized for monitoring ATP in live cells.


Assuntos
Trifosfato de Adenosina/análise , Corantes Fluorescentes/química , Pirenos/química , Zinco/química , Trifosfato de Adenosina/química , Teoria da Densidade Funcional , Corantes Fluorescentes/análise , Células HeLa , Humanos , Íons/química , Limite de Detecção , Espectroscopia de Ressonância Magnética , Microscopia de Fluorescência , Teoria Quântica , Bases de Schiff/química , Zinco/metabolismo
18.
Environ Pollut ; 289: 117863, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352636

RESUMO

Bio-stimulation of the indigenous microbial community is considered as an effective strategy for the bioremediation of polluted environments. This examination explored the near effects of various bio-stimulants on pyrene degradation, prokaryotic community compositions, and functions using 16S rRNA amplicon sequencing and qPCR. At first, the results displayed significant differences (p < 0.05) between the prokaryotic community structures of the control group, PYR (contains pyrene only), and bio-stimulants amended groups. Among the bio-stimulants, biochar, oxalic acid, salicylate, NPK, and ammonium sulfate augmented the pyrene degradation potential of microbial communities. Moreover, the higher abundance of genera, such as Flavobacterium, Hydrogenophaga, Mycobacterium, Rhodococcus, Flavihumibacter, Pseudomonas, Novosphingobium, etc., across the treatments indicated that these genera play a vital role in pyrene metabolism. Based on the higher abundance of GP-RHD and nidA genes, we speculated that Gram-positive prokaryotic communities are more competent in pyrene dissipation than Gram-negative. Furthermore, the marked abundance of nifH, and pqqC genes in the NPK and SA treatments, respectively, suggested that different bio-stimulants might enrich certain bacterial assemblages. Besides, the significant distinctions (p < 0.05) between the bacterial consortia of HA (humic acid) and SA (sodium acetate) groups from NPK, OX (oxalic acid), UR (urea), NH4, and SC (salicylate) groups also suggested that different bio-stimulants might induce distinct ecological impacts influencing the succession of prokaryotic communities in distinct directions. This work provides new insight into the bacterial degradation of pyrene using the bio-stimulation technique. It suggests that it is equally important to investigate the community structure and functions along with studying their impacts on degradation when devising a bio-stimulation technology.


Assuntos
Mycobacterium , Hidrocarbonetos Policíclicos Aromáticos , Biodegradação Ambiental , Mycobacterium/genética , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos , RNA Ribossômico 16S
19.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360967

RESUMO

Microbial biodegradation is one of the acceptable technologies to remediate and control the pollution by polycyclic aromatic hydrocarbon (PAH). Several bacteria, fungi, and cyanobacteria strains have been isolated and used for bioremediation purpose. This review paper is intended to provide key information on the various steps and actors involved in the bacterial and fungal aerobic and anaerobic degradation of pyrene, a high molecular weight PAH, including catabolic genes and enzymes, in order to expand our understanding on pyrene degradation. The aerobic degradation pathway by Mycobacterium vanbaalenii PRY-1 and Mycobactetrium sp. KMS and the anaerobic one, by the facultative bacteria anaerobe Pseudomonas sp. JP1 and Klebsiella sp. LZ6 are reviewed and presented, to describe the complete and integrated degradation mechanism pathway of pyrene. The different microbial strains with the ability to degrade pyrene are listed, and the degradation of pyrene by consortium is also discussed. The future studies on the anaerobic degradation of pyrene would be a great initiative to understand and address the degradation mechanism pathway, since, although some strains are identified to degrade pyrene in reduced or total absence of oxygen, the degradation pathway of more than 90% remains unclear and incomplete. Additionally, the present review recommends the use of the combination of various strains of anaerobic fungi and a fungi consortium and anaerobic bacteria to achieve maximum efficiency of the pyrene biodegradation mechanism.


Assuntos
Klebsiella/metabolismo , Mycobacterium/metabolismo , Pseudomonas/metabolismo , Pirenos/metabolismo , Klebsiella/genética , Consórcios Microbianos , Mycobacterium/genética , Oxigênio/metabolismo , Pseudomonas/genética
20.
Nucleic Acids Res ; 49(15): 8947-8960, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34365512

RESUMO

Several sequences forming G-quadruplex are highly conserved in regulatory regions of genomes of different organisms and affect various biological processes like gene expression. Diverse G-quadruplex properties can be modulated via their interaction with small polyaromatic molecules such as pyrene. To investigate how pyrene interacts with G-rich DNAs, we incorporated deoxyuridine nucleotide(s) with a covalently attached pyrene moiety (Upy) into a model system that forms parallel G-quadruplex structures. We individually substituted terminal positions and positions in the pentaloop of the c-kit2 sequence originating from the KIT proto-oncogene with Upy and performed a detailed NMR structural study accompanied with molecular dynamic simulations. Our results showed that incorporation into the pentaloop leads to structural polymorphism and in some cases also thermal destabilization. In contrast, terminal positions were found to cause a substantial thermodynamic stabilization while preserving topology of the parent c-kit2 G-quadruplex. Thermodynamic stabilization results from π-π stacking between the polyaromatic core of the pyrene moiety and guanine nucleotides of outer G-quartets. Thanks to the prevalent overall conformation, our structures mimic the G-quadruplex found in human KIT proto-oncogene and could potentially have antiproliferative effects on cancer cells.


Assuntos
Quadruplex G , Proteínas Proto-Oncogênicas c-kit/genética , Desoxiuridina/química , Humanos , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Regiões Promotoras Genéticas , Pirenos/química , Termodinâmica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...