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International Journal of Environmental... Sep 2022In soil, polycyclic aromatic hydrocarbons (PAHs) are tightly bound to organic components, but surfactants can effectively transform them from a solid to a liquid phase....
In soil, polycyclic aromatic hydrocarbons (PAHs) are tightly bound to organic components, but surfactants can effectively transform them from a solid to a liquid phase. In this study, the biosurfactant rhamnolipid (RL) was selected as the eluent; shaking elution in a thermostatic oscillator improved the elution rate of pyrene, and the effects of RL concentration, temperature, and elution time on the elution effect were compared. After four repeated washings, the maximum elution rate was 75.6% at a rhamnolipid concentration of 20 g/L and a temperature of 45 °C. We found that 38 μm Zero-Valent Iron (ZVI) had a higher primary reaction rate (0.042 h), with a degradation rate of 94.5% when 3 g/L ZVI was added to 21 mM NaSO at 60 °C. Finally, electron paramagnetic resonance (EPR) detected DMPO-OH and DMPO-SO signals, which played a major role in the degradation of pyrene. Overall, these results show that the combination of rhamnolipid elution and persulfate oxidation system effectively remediated pyrene-contaminated soil and provides some implications for the combined remediation with biosurfactants and chemical oxidation.
Topics: Biodegradation, Environmental; Glycolipids; Iron; Polycyclic Aromatic Hydrocarbons; Pyrenes; Sodium Compounds; Soil; Soil Pollutants; Sulfates; Surface-Active Agents
PubMed: 36141785
DOI: 10.3390/ijerph191811518 -
Applied and Environmental Microbiology Dec 1991We studied the mineralization of pyrene, carbazole, and benzo[a]pyrene in soils obtained from three abandoned coal gasification plants in southern Illinois. The soils...
We studied the mineralization of pyrene, carbazole, and benzo[a]pyrene in soils obtained from three abandoned coal gasification plants in southern Illinois. The soils had different histories of past exposure to hydrocarbon contamination and different amounts of total organic carbon, microbial biomass, and microbial activity. Mineralization was measured by using serum bottle radiorespirometry. The levels of indigenous mineralization of 14C-labeled compounds ranged from 10 to 48% for pyrene, from undetectable to 46% for carbazole, and from undetectable to 25% for benzo[a]pyrene following long-term (greater than 180-day) incubations. Pyrene and carbazole were degraded with short or no lag periods in all soils, but benzo[a]pyrene mineralization occurred after a 28-day lag period. Mineralization was not dependent on high levels of microbial biomass and activity in the soils. Bacterial cultures that were capable of degrading pyrene and carbazole were isolated by enrichment, grown in pure culture, and reintroduced into soils. Reintroduction of a pyrene-degrading bacterium enhanced mineralization to a level of 55% within 2 days, compared with a level of 1% for the indigenous population. The carbazole degrader enhanced mineralization to a level of 45% after 7 days in a soil that showed little indigenous carbazole mineralization. The pyrene and carbazole degraders which we isolated were identified as a Mycobacterium sp. and a Xanthamonas sp., respectively. Our results indicated that mineralization of aromatic hydrocarbons can be significantly enhanced by reintroducing isolated polycyclic aromatic hydrocarbon-degrading bacteria.
Topics: Bacteria; Benzo(a)pyrene; Biodegradation, Environmental; Carbazoles; Kinetics; Minerals; Mycobacterium; Pyrenes; Soil Microbiology; Xanthomonas
PubMed: 1785924
DOI: 10.1128/aem.57.12.3462-3469.1991 -
Journal of Chemical Information and... Apr 2024This work presents new experimental viscosity and density data for aromatic and polyaromatic compounds in binary and ternary pyrene, 1-methylnaphthalene, and dodecane...
Viscosities and Densities of Binary and Ternary Mixtures of Aliphatic and Polyaromatic Hydrocarbons: Pyrene +1-Methylnaphthalene + Dodecane at = (293.15 to 343.15) K. Experiment and Modeling.
This work presents new experimental viscosity and density data for aromatic and polyaromatic compounds in binary and ternary pyrene, 1-methylnaphthalene, and dodecane mixtures. The lack of experimental viscosity data for these mixtures requires the development of a new database, which is vital for understanding the behavior of mixtures in more complex systems, such as asphaltenes and fuels. The mixtures proposed in this work have been measured over a temperature range of (293.15 to 343.15) K at atmospheric pressure. Several mixture compositions have been studied at these conditions: 1.0, 2.5, 5.0, 7.5, 10.0, 12.5, and 15.0% pyrene mass fraction. The concentration of pyrene correlates with an increase in the viscosity and density values. At the lowest temperature in binary mixtures, the corresponding values reach 4.4217 mPa·s for viscosity and 1.0447 × 10 kg·m for density, respectively. In ternary mixtures, the introduction of dodecane leads to the lowest maximum values of 3.5555 mPa·s for viscosity and 1.0112 × 10 kg·m for density at the same temperature. The experimental data have been employed for the specific modification of viscosity models. These modifications could facilitate the prediction of the viscosity of mixtures that are more complex than those presented in this work. Various viscosity models have been employed, such as Linear, Ratcliff and Khan, modified UNIFAC-Visco, and Krieger-Dougherty. The settings in the models used reliably reproduce the experiment reliably. However, the Ratcliff model agrees excellently with the experiment, having a low standard deviation (2.0%) compared to other models. Furthermore, a model based on the equation of state of Guo is proposed to predict the viscosity values by modifying the specific parameters and adjusting them to the mixtures proposed in this work. The results from this study are compared to previous work, where pyrene, toluene, and heptane mixtures were analyzed. In this case, we find that the decrease of aggregation grade in the present systems is predicted by the model fixed in this work.
Topics: Pyrenes; Viscosity; Naphthalenes; Alkanes; Temperature; Models, Chemical; Polycyclic Aromatic Hydrocarbons
PubMed: 38500402
DOI: 10.1021/acs.jcim.3c01737 -
Molecules (Basel, Switzerland) Nov 2017In this review, we summarize the recent advances in the use of pyrene-modified oligonucleotides as a platform for functional nucleic acid-based constructs. Pyrene is of... (Review)
Review
In this review, we summarize the recent advances in the use of pyrene-modified oligonucleotides as a platform for functional nucleic acid-based constructs. Pyrene is of special interest for the development of nucleic acid-based tools due to its unique fluorescent properties (sensitivity of fluorescence to the microenvironment, ability to form excimers and exciplexes, long fluorescence lifetime, high quantum yield), ability to intercalate into the nucleic acid duplex, to act as a π-π-stacking (including anchoring) moiety, and others. These properties of pyrene have been used to construct novel sensitive fluorescent probes for the sequence-specific detection of nucleic acids and the discrimination of single nucleotide polymorphisms (SNPs), aptamer-based biosensors, agents for binding of double-stranded DNAs, and building blocks for supramolecular complexes. Special attention is paid to the influence of the design of pyrene-modified oligonucleotides on their properties, i.e., the structure-function relationships. The perspectives for the applications of pyrene-modified oligonucleotides in biomolecular studies, diagnostics, and nanotechnology are discussed.
Topics: Biosensing Techniques; DNA; Fluorescent Dyes; Models, Molecular; Nanotechnology; Nucleic Acid Conformation; Nucleic Acids; Oligonucleotide Probes; Pyrenes; RNA
PubMed: 29189716
DOI: 10.3390/molecules22122108 -
Nature Communications Nov 2020Since the fluorescent reagent N-(1-pyrene)iodoacetamide was first used to label skeletal muscle actin in 1981, the pyrene-labeled actin has become the most widely...
Since the fluorescent reagent N-(1-pyrene)iodoacetamide was first used to label skeletal muscle actin in 1981, the pyrene-labeled actin has become the most widely employed tool to measure the kinetics of actin polymerization and the interaction between actin and actin-binding proteins. Here we report high-resolution cryo-electron microscopy structures of actin filaments with N-1-pyrene conjugated to cysteine 374 and either ADP (3.2 Å) or ADP-phosphate (3.0 Å) in the active site. Polymerization buries pyrene in a hydrophobic cavity between subunits along the long-pitch helix with only minor differences in conformation compared with native actin filaments. These structures explain how polymerization increases the fluorescence 20-fold, how myosin and cofilin binding to filaments reduces the fluorescence, and how profilin binding to actin monomers increases the fluorescence.
Topics: Actin Cytoskeleton; Actins; Adenosine Diphosphate; Adenosine Triphosphate; Binding Sites; Catalytic Domain; Cryoelectron Microscopy; Fluorescence; Hydrophobic and Hydrophilic Interactions; Iodoacetamide; Kinetics; Microfilament Proteins; Phosphates; Polymerization; Protein Binding; Pyrenes
PubMed: 33214556
DOI: 10.1038/s41467-020-19762-1 -
Ecotoxicology and Environmental Safety Dec 2021A slow degradation rate and low transformation efficiency are the main problems in the biodegradation of polycyclic aromatic hydrocarbons (PAHs). This study selected...
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.
Topics: Ions; Iron; Pyrenes; Rhodococcus
PubMed: 34560613
DOI: 10.1016/j.ecoenv.2021.112789 -
Biochimica Et Biophysica Acta Mar 2013Molecular dynamics (MD) simulations of bilayers of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) with varying amounts of cholesterol (0, 5, 20, and 40mol%)...
Molecular dynamics (MD) simulations of bilayers of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) with varying amounts of cholesterol (0, 5, 20, and 40mol%) were carried out in the absence and presence of inserted pyrene molecules. Both fluorophore and bilayer parameters were computed, for characterization of probe location and dynamics, as well as its effects on the host bilayer. In agreement with previous studies in fluid disordered bilayers, pyrene prefers to be located in the hydrophobic acyl chain region of POPC bilayers, close to the glycerol group of lipid molecules and causes ordering of the lipid acyl chains. However, incorporation of pyrene in binary POPC/cholesterol bilayers decreases the acyl chain order parameter (especially near the end of the chains), opposing the ordering effect of cholesterol. These effects are modest and mainly felt locally. Significantly, as the bilayer is enriched with cholesterol, the relative position of pyrene and the POPC carbonyl and phosphocholine groups is invariant, and the local water density around the probe decreases. This work clarifies and supports the cautious use of pyrene Ham effect to effectively measure equivalent polarity in lipid bilayers. Within the time scale of the MD simulations, which is of the magnitude of the fluorescence lifetime of pyrene, the thermally averaged polarity of lipid bilayers is nearly out of influence of spurious uncertainty in the transverse location of pyrene in the bilayers. This renders the values of equivalent polarity measurements through the pyrene Ham effect more reliable and reproducible than previously expected.
Topics: Biophysics; Cholesterol; Computer Simulation; Dose-Response Relationship, Drug; Fluorescent Dyes; Lipid Bilayers; Lipids; Molecular Conformation; Molecular Dynamics Simulation; Phosphatidylcholines; Pyrenes; Temperature; Water
PubMed: 23274277
DOI: 10.1016/j.bbamem.2012.12.014 -
Microbial Ecology Jul 2023Biodegradation of polycyclic aromatic hydrocarbons (PAHs) under completely anaerobic sulfate-reducing conditions is an energetically challenging process. To date,...
Biodegradation of polycyclic aromatic hydrocarbons (PAHs) under completely anaerobic sulfate-reducing conditions is an energetically challenging process. To date, anaerobic degradations of only two-ringed naphthalene and three-ringed phenanthrene by sediment-free and enriched sulfate-reducing bacteria have been reported. In this study, sulfate-reducing enrichment cultures capable of degrading naphthalene and four-ringed PAH, pyrene, were enriched from a contaminated former gas plant site soil. Bacterial community composition analysis revealed that a naphthalene-degrading enrichment culture, MMNap, was dominated (84.90%) by a Gram-positive endospore-forming member of the genus Desulfotomaculum with minor contribution (8.60%) from a member of Clostridium. The pyrene-degrading enrichment, MMPyr, was dominated (97.40%) by a species of Desulfotomaculum. The sequences representing the Desulfotomaculum phylotypes shared 98.80% similarity to each other. After 150 days of incubation, MMNap degraded 195 µM naphthalene with simultaneous reduction of sulfate and accumulation of sulfide. Similarly, MMPyr degraded 114 µM pyrene during 180 days of incubation with nearly stochiometric sulfate consumption and sulfide accumulation. In both cases, the addition of sulfate reduction inhibitor, molybdate (20 mM), resulted in complete cessation of the substrate utilization and sulfate reduction that clearly indicated the major role of the sulfate-reducing Desulfotomaculum in biodegradation of the two PAHs. This study is the first report on anaerobic pyrene degradation by a matrix-free, strictly anaerobic, and sulfate-reducing enrichment culture.
Topics: Anaerobiosis; Sulfates; Naphthalenes; Polycyclic Aromatic Hydrocarbons; Pyrenes; Biodegradation, Environmental
PubMed: 35610382
DOI: 10.1007/s00248-022-02042-4 -
Environmental Health Perspectives Jan 2021The filaggrin protein is important for skin barrier structure and function. Loss-of-function (null) mutations in the filaggrin gene may increase dermal absorption of...
BACKGROUND
The filaggrin protein is important for skin barrier structure and function. Loss-of-function (null) mutations in the filaggrin gene may increase dermal absorption of chemicals.
OBJECTIVE
The objective of the study was to clarify if dermal absorption of chemicals differs depending on genotype.
METHOD
We performed a quantitative real-time polymerase chain reaction (qPCR)-based genetic screen for loss-of-function mutations ( null) in 432 volunteers from the general population in southern Sweden and identified 28 null carriers. In a dermal exposure experiment, we exposed 23 null and 31 wild-type (wt) carriers to three organic compounds common in the environment: the polycyclic aromatic hydrocarbon pyrene, the pesticide pyrimethanil, and the ultraviolet-light absorber oxybenzone. We then used liquid-chromatography mass-spectrometry to measure the concentrations of these chemicals or their metabolites in the subjects' urine over 48 h following exposure. Furthermore, we used long-range PCR to measure repeat copy number variants (CNV), and we performed population toxicokinetic analysis.
RESULTS
Lag times for the uptake and dermal absorption rate of the chemicals differed significantly between null and wt carriers with low (20-22 repeats) and high CNV (23-24 repeats). We found a dose-dependent effect on chemical absorption with increasing lag times by increasing CNV for both pyrimethanil and pyrene, and decreasing area under the urinary excretion rate curve () with increasing CNV for pyrimethanil. null carriers excreted 18% and 110% more metabolite (estimated by ) for pyrimethanil than wt carriers with low and high CNV, respectively.
CONCLUSION
We conclude that genotype influences the dermal absorption of some common chemicals. Overall, null carriers were the most susceptible, with the shortest lag time and highest rate constants for skin absorption, and higher fractions of the applied dose excreted. Furthermore, our results indicate that low CNV resulted in increased dermal absorption of chemicals. https://doi.org/10.1289/EHP7310.
Topics: Benzophenones; Chromatography, Liquid; DNA Copy Number Variations; Environmental Pollutants; Female; Filaggrin Proteins; Genotype; Humans; Intermediate Filament Proteins; Male; Mass Spectrometry; Mutation; Pyrenes; Pyrimidines; Skin Absorption; Sweden
PubMed: 33439052
DOI: 10.1289/EHP7310 -
Organic & Biomolecular Chemistry Oct 2023The supramolecular self-assembly of pyrene-DNA conjugates into nanostructures is presented. DNA functionalized with different types of pyrene isomers at the 3'-end...
The supramolecular self-assembly of pyrene-DNA conjugates into nanostructures is presented. DNA functionalized with different types of pyrene isomers at the 3'-end self-assemble into nano-objects. The shape of the nanostructures is influenced by the type of pyrene isomer appended to the DNA. Multilamellar vesicles are observed with the 1,6- and 1,8-isomers, whereas conjugates of the 2,7-isomer exclusively assemble into spherical nanoparticles. Self-assembled nano-spheres obtained with the 2,7-dialkynyl pyrene isomer were used for the construction of an artificial light-harvesting complex (LHC) in combination with Cy3 as the energy acceptor.
Topics: Nanostructures; DNA; Nanoparticles; Pyrenes
PubMed: 37750811
DOI: 10.1039/d3ob01375h