RESUMEN
Food waste (FW) and its biogas residue were considered as sources of terrestrial microplastics (MPs) and phthalic acid esters (PAEs) contamination. However, there was a lack of research and understanding of the MPs and PAEs pollution problem in FW dry anaerobic digestion process (DADP). The MPs and PAEs in three stages of the DADP with the largest monomer disposal scale in China were identified. At the biogas residue extrusion stage, MPs abundance and PAEs concentration reached the highest values, which were 3.63 ± 0.45 × 103 N·kg-1 and 3.62 ± 0.72 mg·kg-1, respectively. Furthermore, there was a significant positive correlation between MPs and PAEs throughout the process (p < 0.05). Although bacteria and fungi with plastic degradation potential were present in all stages, the contamination problem of MPs and PAEs cannot be completely solved through DADP. This study provides a scientific basis for preventing and controlling the pollution of MPs and PAEs.
Asunto(s)
Biodegradación Ambiental , Ésteres , Alimento Perdido y Desperdiciado , Microplásticos , Ácidos Ftálicos , Anaerobiosis , Bacterias/metabolismo , Ésteres/metabolismo , Hongos/metabolismo , Ácidos Ftálicos/metabolismo , Eliminación de Residuos/métodosRESUMEN
Alternative plasticizers such as diisononyl-1,2-cyclohexanedicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHTP), and di(2-ethylhexyl) adipate (DEHA) are progressively replacing phthalates in many consumer and professional products because of adverse effects on reproduction associated with some phthalates. Human exposures to these phthalate substitutes can occur through ingestion, skin absorption and inhalation. Skin uptake can lead to greater concentration at the target organs compared to ingestion because the skin exposure route bypasses the first-pass effect. Skin absorption studies are almost absent for these alternative plasticizers. We therefore wanted first, to characterize skin absorption of a mixture containing DINCH, DEHA and DEHTP in vitro using a flow-through diffusion cell system with ex vivo human skin, quantifying their respective monoester metabolites (mono-isononyl-cyclohexane-1,2-dicarboxylate (MINCH), mono-2-ethylhexyl adipate (MEHA), mono-2-ethylhexyl terephthalate (MEHTP), respectively); second, to validate these results by exposing five human volunteers to this mixture on their forearm and quantifying the corresponding urinary metabolites (including the monoesters and their oxidation products). Our study showed that two of these alternative plasticizers, DEHTP and DINCH, did not permeate skin showing as quantifiable metabolite levels in vitro and only traces of DEHA were quantified as its monoester metabolite, MEHA. Permeation coefficient (Kp) 0.06 and 55.8*10-7 cm/h for neat and emulsified DEHA, respectively, while the permeation rate (J) remained low for both (0.005 and 0.001⯵g/cm2/h, respectively). Participants exposed to a mixture of these three plasticizers did not have noteworthy urinary concentrations of their respective metabolites after 24â¯hours post-application. However, the alternative plasticizer mixture was completely absorbed after six hours post-application on the forearms of the human volunteers, and the urinary elimination curves showed a slight increase after 24â¯hours post-application. Further studies on skin absorption of these substances should follow the urinary elimination kinetics of these metabolites more than 24â¯hours post-application. We also recommend quantifying the parent compounds in the in vitro diffusion experiments.
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Adipatos , Ácidos Dicarboxílicos , Ácidos Ftálicos , Plastificantes , Absorción Cutánea , Humanos , Plastificantes/farmacocinética , Plastificantes/toxicidad , Plastificantes/metabolismo , Ácidos Dicarboxílicos/farmacocinética , Ácidos Dicarboxílicos/metabolismo , Ácidos Dicarboxílicos/orina , Adipatos/metabolismo , Adipatos/farmacocinética , Adipatos/orina , Ácidos Ftálicos/farmacocinética , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/orina , Adulto , Femenino , Piel/metabolismo , Ácidos Ciclohexanocarboxílicos/farmacocinética , Ácidos Ciclohexanocarboxílicos/metabolismo , Masculino , Adulto Joven , GlicolesRESUMEN
Dienelactone hydrolase (DLH) is one of numerous hydrolytic enzymes with an α/ß-hydrolase fold, which catalyze the hydrolysis of dienelactone to maleylacetate. The DLHs share remarkably similar tertiary structures and a conserved arrangement of catalytic residues. This study presents the crystal structure and comprehensive functional characterization of a novel thermostable DLH from the bacterium Hydrogenobacter thermophilus (HtDLH). The crystal structure of the HtDLH, solved at a resolution of about 1.67â¯Å, exhibits a canonical α/ß-hydrolase fold formed by eight ß-sheet strands in the core, with one buried α-helix and six others exposed to the solvent. The structure also confirmed the conserved catalytic triad of DHLs formed by Cys121, Asp170, and His202 residues. The HtDLH forms stable homodimers in solution. Functional studies showed that HtDLH has the expected esterase activity over esters with short carbon chains, such as p-nitrophenyl acetate, reaching optimal activity at pH 7.5 and 70⯰C. Furthermore, HtDLH maintains more than 50â¯% of its activity even after incubation at 90⯰C for 16â¯h. Interestingly, HtDLH exhibits catalytic activity towards polyethylene terephthalate (PET) monomers, including bis-1,2-hydroxyethyl terephthalate (BHET) and 1-(2-hydroxyethyl) 4-methyl terephthalate, as well as other aliphatic and aromatic esters. These findings associated with the lack of activity on amorphous PET indicate that HtDLH has characteristic of a BHET-degrading enzyme. This work expands our understanding of enzyme families involved in PET degradation, providing novel insights for plastic biorecycling through protein engineering, which could lead to eco-friendly solutions to reduce the accumulation of plastic in landfills and natural environments.
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Hidrolasas de Éster Carboxílico , Estabilidad de Enzimas , Especificidad por Sustrato , Cristalografía por Rayos X , Hidrolasas de Éster Carboxílico/metabolismo , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/genética , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/química , Ésteres/metabolismo , Ésteres/química , Modelos Moleculares , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Conformación Proteica , Concentración de Iones de Hidrógeno , Cinética , Hidrólisis , Dominio Catalítico , TemperaturaRESUMEN
Plastic additives, such as phthalates, are ubiquitous contaminants that can have detrimental impacts on marine organisms and overall ecosystems' health. Valuable information about the status and resilience of marine ecosystems can be obtained through the monitoring of key indicator species, such as cetaceans. In this study, fatty acid profiles and phthalates were examined in blubber biopsies of free-ranging individuals from two delphinid species (short-finned pilot whale - Globicephala macrorhynchus, n = 45; common bottlenose dolphin - Tursiops truncatus, n = 39) off Madeira Island (NE Atlantic). This investigation aimed to explore the relations between trophic niches (epipelagic vs. mesopelagic), contamination levels, and the health status of individuals within different ecological and biological groups (defined by species, residency patterns and sex). Multivariate analysis of selected dietary fatty acids revealed a clear niche segregation between the two species. Di-n-butylphthalate (DBP), diethyl phthalate (DEP), and bis(2-ethylhexyl) phthalate (DEHP) were the most prevalent among the seven studied phthalates, with the highest concentration reached by DEHP in a bottlenose dolphin (4697.34 ± 113.45 ng/g). Phthalates esters (PAEs) concentration were higher in bottlenose dolphins (Mean ∑ PAEs: 947.56 ± 1558.34 ng/g) compared to pilot whales (Mean ∑ PAEs: 229.98 ± 158.86 ng/g). In bottlenose dolphins, DEHP was the predominant phthalate, whereas in pilot whales, DEP and DBP were more prevalent. Health markers suggested pilot whales might suffer from poorer physiological conditions than bottlenose dolphins, although high metabolic differences were seen between the two species. Phthalate levels showed no differences by ecological or biological groups, seasons, or years. This study is the first to assess the extent of plastic additive contamination in free-ranging cetaceans from a remote oceanic island system, underscoring the intricate relationship between ecological niches and contaminant exposure. Monitoring these chemicals and their potential impacts is vital to assess wild population health, inform conservation strategies, and protect critical species and habitats.
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Delfín Mular , Monitoreo del Ambiente , Ácidos Grasos , Ácidos Ftálicos , Contaminantes Químicos del Agua , Calderón , Animales , Ácidos Ftálicos/metabolismo , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Ácidos Grasos/metabolismo , Calderón/metabolismo , Masculino , Delfín Mular/metabolismo , Femenino , Ecosistema , Biomarcadores/metabolismo , Dietilhexil Ftalato/metabolismoRESUMEN
Simultaneous biodegradation of multiple micropollutantslike polycyclic aromatic hydrocarbons (PAHs) and phthalates (PAEs) by microbial consortia remain unclear. Here, four distinct bacterial consortia capable of degrading PAHs and PAEs were domesticated from sludge and its composts. PAH-degrading consortium HS and PAE-degrading consortium EC2 displayed the highest degradation efficiencies for PAHs (37 %-99 %) and PAEs (98 %-99 %), respectively, being significantly higher than those of individual member strains. Consortia HS and EC2 could simultaneously degrade both PAHs and PAEs. Remarkably, a synthetic consortium Syn by co-culturing consortia HS and EC2 demonstrated proficient simultaneous biodegradation for both PAHs (65 %-98 %) and PAEs (91 %-97 %). These consortia changed their community structure with enriching pollutant-degrading genera and extracellular polymeric substance contents to promote simultaneous biodegradation of multiple pollutants. Moreover, consortium Syn significantly enhanced degradation of both PAHs and PAEs in soil and sludge. This study provides strong candidates for simultaneous bioremediation of complex polluted environments by PAHs and PAEs.
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Biodegradación Ambiental , Consorcios Microbianos , Ácidos Ftálicos , Hidrocarburos Policíclicos Aromáticos , Aguas del Alcantarillado , Contaminantes del Suelo , Aguas del Alcantarillado/microbiología , Hidrocarburos Policíclicos Aromáticos/metabolismo , Contaminantes del Suelo/metabolismo , Ácidos Ftálicos/metabolismo , Bacterias/metabolismo , Microbiología del SueloRESUMEN
Synthetic aromatic esters, widely employed in agriculture, food, and chemical industries, have become emerging environmental pollutants due to their strong hydrophobicity and poor bioavailability. This study attempted to address this issue by extracellularly expressing the promiscuous aminopeptidase (Aps) from Pseudomonas aeruginosa GF31 in B. subtilis, achieving an impressive enzyme activity of 13.7 U/mg. Notably, we have demonstrated, for the first time, the Aps-mediated degradation of diverse aromatic esters, including but not limited to pyrethroids, phthalates, and parabens. A biochemical characterization of Aps reveals its esterase properties and a broader spectrum of substrate profiles. The degradation rates of p-nitrobenzene esters (p-NB) with different side chain structures vary under the action of Aps, showing a preference for substrates with relatively longer alkyl side chains. The structure-dependent degradability aligns well with the binding energies between Aps and p-NB. Molecular docking and enzyme-substrate interaction elucidate that hydrogen bonding, hydrophobic interactions, and π-π stacking collectively stabilize the enzyme-substrate conformation, promoting substrate hydrolysis. These findings provide new insights into the enzymatic degradation of aromatic ester pollutants, laying a foundation for the further development and modification of promiscuous enzymes.
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Aminopeptidasas , Proteínas Bacterianas , Ésteres , Simulación del Acoplamiento Molecular , Pseudomonas aeruginosa , Hidrólisis , Ésteres/metabolismo , Ésteres/química , Aminopeptidasas/metabolismo , Aminopeptidasas/química , Aminopeptidasas/genética , Especificidad por Sustrato , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Pseudomonas aeruginosa/enzimología , Biodegradación Ambiental , Cinética , Bacillus subtilis/enzimología , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismoRESUMEN
Phthalates used in the industry penetrate the environment and negatively affect humans and animals. Hair samples seem to be the best matrix for studies on long-term exposure to phthalates, but till now they were used only in investigations on humans. Moreover, the knowledge of the wild terrestrial animal exposure to phthalates is extremely limited. This study aimed to establish of concentration levels of selected phthalate metabolites (i.e. monomethyl phthalate-MMP, monoethyl phthalate-MEP, mono-isobutyl phthalate-MiBP, monobutyl phthalate-MBP, monobenzyl phthalate-MBzP, mono-cyclohexyl phthalate-MCHP, mono(2-ethylhexyl) phthalate-MEHP and mono-n-octyl phthalate-MOP) in wild boar hair samples using liquid chromatography with mass spectrometry (LC-MS) analysis. MEHP was noted in 90.7% of samples with mean 66.17 ± 58.69 pg/mg (median 49.35 pg/mg), MMP in 59.3% with mean 145.1 ± 310.6 pg/mg (median 64.45 pg/mg), MiBP in 37.0% with mean 56.96 ± 119.4 pg/mg (median < limit of detection-LOD), MBP in 35.2% with mean 19.97 ± 34.38 pg/mg (median < LOD) and MBzP in 1.9% with concentration below limit of quantification. MEP, MCHP, and MOP have not been found in wild boar hair samples during this study. The results have shown that wild boars are exposed to phthalates and hair samples may be used as a matrix during studies on levels of phthalate metabolites in wild animals.
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Cabello , Ácidos Ftálicos , Sus scrofa , Animales , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/análisis , Cabello/química , Cabello/metabolismo , Sus scrofa/metabolismo , Cromatografía Liquida , Monitoreo del Ambiente/métodos , PorcinosRESUMEN
Phthalate esters (PAEs) are emerging hazardous and toxic chemicals that are extensively used as plasticizers or additives. Diethyl phthalate (DEP) and dimethyl phthalate (DMP), two kinds of PAEs, have been listed as the priority pollutants by many countries. PAE hydrolases are the most effective enzymes in PAE degradation, among which family IV esterases are predominate. However, only a few PAE hydrolases have been characterized, and as far as we know, no crystal structure of any PAE hydrolases of the family IV esterases is available to date. HylD1 is a PAE hydrolase of the family IV esterases, which can degrade DMP and DEP. Here, the recombinant HylD1 was characterized. HylD1 maintained a dimer in solution, and functioned under a relatively wide pH range. The crystal structures of HylD1 and its complex with monoethyl phthalate were solved. Residues involved in substrate binding were identified. The catalytic mechanism of HylD1 mediated by the catalytic triad Ser140-Asp231-His261 was further proposed. The hylD1 gene is widely distributed in different environments, suggesting its important role in PAEs degradation. This study provides a better understanding of PAEs hydrolysis, and lays out favorable bases for the rational design of highly-efficient PAEs degradation enzymes for industrial applications in future.
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Ácidos Ftálicos , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Ésteres/química , Hidrólisis , Cristalografía por Rayos X , Catálisis , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/metabolismo , Hidrolasas de Éster Carboxílico/genéticaRESUMEN
Field research on phthalate monoesters (MPEs) and their relationships with phthalate esters (PAEs) is limited, especially in wild fishes. Here, PAEs and MPEs were measured in surface water, sediment, and wild fish collected from a representative river basin with high economic development. Several metabolites of emerging plasticizers, such as mono(3,5,5-trimethyl-1-hexyl) phthalate and mono(6-oxo-2-propylheptyl) phthalate, have already existed in fish with high detection frequencies (95 % and 100 %). Monobutyl phthalate and mono(2-ethylhexyl) phthalate were the predominant MPEs in fish and natural environment (surface water and sediment), while bis(2-ethylhexyl) phthalate was the most abundant PAEs in all matrices. The total concentrations (median) of 9 PAEs and 16 MPEs were 5980 and 266 ng/L in water, 231 and 10.6 ng/g (dw) in sediment, and 209 and 32.5 ng/g (ww) in fish, respectively. The occurrence of MPEs was highly related to their parent PAEs, with similar spatial distribution characteristics in the aquatic environments. Moreover, municipal wastewater discharge was recognized as the main source of MPEs in the research area. Fish species can accumulate targeted chemicals, and it seems more MPEs were from the PAE degradation in fish other than the direct uptake of MPEs in water. Parent PAEs showed higher ecological risk than their corresponding metabolites.
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Monitoreo del Ambiente , Ésteres , Peces , Sedimentos Geológicos , Ácidos Ftálicos , Contaminantes Químicos del Agua , Ácidos Ftálicos/análisis , Ácidos Ftálicos/metabolismo , Contaminantes Químicos del Agua/análisis , Animales , Peces/metabolismo , Sedimentos Geológicos/química , Sedimentos Geológicos/análisis , Ésteres/análisis , Ríos/química , Plastificantes/análisis , Plastificantes/metabolismo , Medición de RiesgoRESUMEN
It has been well-investigating that individual phthalates (PAEs) or polycyclic aromatic hydrocarbons (PAHs) affect public health. However, there is still a gap that the mixture of PAEs and PAHs impacts birth outcomes. Through innovative methods for mixtures in epidemiology, we used a metabolome Exposome-Wide Association Study (mExWAS) to evaluate and explain the association between exposure to PAEs and PAHs mixtures and birth outcomes. Exposure to a higher level of PAEs and PAHs mixture was associated with lower birth weight (maximum cumulative effect: 143.5 g) rather than gestational age. Mono(2-ethlyhexyl) phthalate (MEHP) (posterior inclusion probability, PIP = 0.51), 9-hydroxyphenanthrene (9-OHPHE) (PIP = 0.53), and 1-hydroxypyrene (1-OHPYR) (PIP = 0.28) were identified as the most important compounds in the mixture. In mExWAS, we successfully annotated four overlapping metabolites associated with both MEHP/9-OHPHE/1-OHPYR and birth weight, including arginine, stearamide, Arg-Gln, and valine. Moreover, several lipid-related metabolism pathways, including fatty acid biosynthesis and degradation, alpha-linolenic acid, and linoleic acid metabolism, were disturbed. In summary, these findings may provide new insights into the underlying mechanisms by which PAE and PAHs affect fetal growth.
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Metaboloma , Ácidos Ftálicos , Hidrocarburos Policíclicos Aromáticos , Hidrocarburos Policíclicos Aromáticos/metabolismo , Ácidos Ftálicos/metabolismo , Humanos , Femenino , Embarazo , Metaboloma/efectos de los fármacos , Peso al Nacer/efectos de los fármacos , Exposoma , Contaminantes Ambientales/metabolismo , Exposición Materna/estadística & datos numéricos , Recién Nacido , AdultoRESUMEN
BACKGROUND: Emerging evidence has shown the potential involvement of phthalates (PAEs) exposure in the development of dementia with Lewy bodies (DLB). Metabolomics can reflect endogenous metabolites variation in the progress of disease after chemicals exposure. However, little is known about the association between PAEs, gut microbiota and metabolome in DLB. OBJECTIVE: We aim to explore the intricate relationship among urinary PAEs metabolites (mPAEs), dysbiosis of gut bacteria, and metabolite profiles in DLB. METHODS: A total of 43 DLB patients and 45 normal subjects were included in this study. Liquid chromatography was used to analyze the levels of mPAEs in the urine of the two populations. High-throughput sequencing and liquid chromatography-mass spectrometry were used to analyze gut microbiota and the profile of gut metabolome, respectively. The fecal microbiota transplantation (FMT) experiment was performed to verify the potential role of mPAEs on gut dysbiosis contribute to aggravating cognitive dysfunction in α-synuclein tg DLB/PD mice. RESULTS: The DLB patients had higher DEHP metabolites (MEOHP, MEHHP and MEHP), MMP and MnBP, lower MBP and MBzP than the control group and different microbiota. A significantly higher abundance of Ruminococcus gnavus and lower Prevotella copri, Prevotella stercorea and Bifidobacterium were observed in DLB. Higher 3 DEHP metabolites, MMP, MnBP and lower MBP and MBzP were significantly negatively associated with Prevotella copri, Prevotella stercorea and Bifidobacterium. Additionally, using metabolomics, we found that altered bile acids, short-chain fatty acids and amino acids metabolism are linked to these mPAEs. We further found that FMT of fecal microbiota from highest DEHP metabolites donors significantly impaired cognitive function in the germ-free DLB/PD mice. CONCLUSION: Our study suggested that PAEs exposure may alter the microbiota-gut-brain axis and providing novel insights into the interactions among environmental perturbations and microbiome-host in pathogenesis of DLB.
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Exposición a Riesgos Ambientales , Microbioma Gastrointestinal , Enfermedad por Cuerpos de Lewy , Metaboloma , Ácidos Ftálicos , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Ácidos Ftálicos/metabolismo , Metaboloma/efectos de los fármacos , Ratones , Animales , Masculino , Femenino , Anciano , Enfermedad por Cuerpos de Lewy/metabolismo , Enfermedad por Cuerpos de Lewy/microbiología , Disbiosis/inducido químicamente , Disbiosis/microbiología , Persona de Mediana EdadRESUMEN
More than 8 billion tons of plastic waste has been generated, posing severe environmental consequences and health risks. Due to prolonged exposure, microplastic particles are found in human blood and other bodily fluids. Despite a lack of toxicity studies regarding microplastics, harmful effects for humans seem plausible and cannot be excluded. As small plastic particles readily translocate from the gut to body fluids, enzyme-based treatment of serum could constitute a promising future avenue to clear synthetic polymers and their corresponding oligomers via their degradation into monomers of lower toxicity than the material they originate from. Still, whereas it is known that the enzymatic depolymerization rate of synthetic polymers varies by orders of magnitude depending on the buffer and media composition, the activity of plastic-degrading enzymes in serum was unknown. Here, we report how an engineered PETase, which we show to be generally trans-selective via induced fit docking, can depolymerize two different microplastic-like substrates of the commodity polymer polyethylene terephthalate (PET) into its non-toxic monomer terephthalic acid (TPA) alongside mono(2-hydroxyethyl)terephthalate (MHET) in human serum at 37 °C. We show that the application of PETase does not influence cell viability in vitro. Our work highlights the potential of applying biocatalysis in biomedicine and represents a first step towards finding a future solution to the problem that microplastics in the bloodstream may pose.
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Microplásticos , Tereftalatos Polietilenos , Humanos , Tereftalatos Polietilenos/química , Tereftalatos Polietilenos/metabolismo , Microplásticos/química , Burkholderiales/química , Burkholderiales/metabolismo , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismoRESUMEN
Poly(butylene adipate-co-terephthalate) (PBAT) is widely utilized in the production of food packaging and mulch films. Its extensive application has contributed significantly to global solid waste, posing numerous environmental challenges. Recently, enzymatic recycling has emerged as a promising eco-friendly solution for the management of plastic waste. Here, we systematically investigate the depolymerization mechanism of PBAT catalyzed by cutinase TfCutSI with molecular docking, molecular dynamics simulations, and quantum mechanics/molecular mechanics calculations. Although the binding affinities for acid ester and terephthalic acid ester bonds are similar, a regioselective depolymerization mechanism and a "chain-length" effect on regioselectivity were proposed and evidenced. The regioselectivity is highly associated with specific structural parameters, namely Substrate@O4-Met@H7 and Substrate@C1-Ser@O1 distances. Notably, the binding mode of BTa captured by X-ray crystallography does not facilitate subsequent depolymerization. Instead, a previously unanticipated binding mode, predicted through computational analysis, is confirmed to play a crucial role in BTa depolymerization. This finding proves the critical role of computational modelling in refining experimental results. Furthermore, our results revealed that both the hydrogen bond network and enzyme's intrinsic electric field are instrumental in the formation of the final product. In summary, these novel molecular insights into the PBAT depolymerization mechanism offer a fundamental basis for enzyme engineering to enhance industrial plastic recycling.
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Simulación del Acoplamiento Molecular , Poliésteres , Polimerizacion , Poliésteres/química , Poliésteres/metabolismo , Simulación de Dinámica Molecular , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Estereoisomerismo , Hidrolasas de Éster CarboxílicoRESUMEN
Population studies reveal widespread exposure to phthalates. Understanding their absorption, distribution, metabolism, and excretion is vital to reduce exposure. However, data on skin absorption remain limited. We thus aim to characterize the skin permeation of three phthalates in a mixture, neat or in emulsion; di(2-ethylhexyl) phthalate (d4-DEHP), dibutyl phthalate (d4-DBP), and diethyl phthalate (d4-DEP), by comparing in vitro human skin (800⯵m) permeation (24â¯hours) results using flow-through diffusion cells with urine results obtained from volunteers exposed to the same mixture applied to a forearm (40â¯cm2). Metabolites were analyzed in receptor fluids and urine. Phthalates crossed the skin barrier and metabolized into monoesters before elimination. Increased permeation was observed for phthalates in emulsion compared to neat substances, with polyethylene glycol (PEG) in the receptor fluid enhancing emulsion permeation, but not affecting neat substances. In vitro results mirrored in vivo findings: DEP showed rapid permeation (J: â¼2â¯ug/cm2/h) and urinary excretion peaking at six hours post-application, whereas DBP exhibited slower kinetics (J: â¼0.1â¯ug/cm2/h), with a urinary peak at 15-17â¯hours post-application. DEHP had minimal permeation (J: â¼0.0002â¯ug/cm2/h) with no observable urinary peak. These findings underscore the importance of comprehending phthalate skin absorption for effective exposure mitigation strategies.
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Dibutil Ftalato , Ácidos Ftálicos , Absorción Cutánea , Piel , Humanos , Ácidos Ftálicos/farmacocinética , Ácidos Ftálicos/orina , Ácidos Ftálicos/metabolismo , Adulto , Masculino , Dibutil Ftalato/farmacocinética , Dibutil Ftalato/orina , Dibutil Ftalato/metabolismo , Piel/metabolismo , Femenino , Dietilhexil Ftalato/farmacocinética , Dietilhexil Ftalato/metabolismo , Dietilhexil Ftalato/orina , Adulto Joven , Persona de Mediana Edad , Administración Cutánea , EmulsionesRESUMEN
Plant uptake of organic contaminants generally occurs through either root, gas-phase foliar, or particle-phase foliar uptake. Understanding these pathways is essential for food-system practitioners to reduce human exposures, and to clean contaminated-sites with phytoremediation. Herein, we conducted a field-based experiment using an improved specific exposure chamber to elucidate the uptake pathways of organophosphate esters, phthalates, and polycyclic aromatic compounds, and quantitatively assessed their contributions to organic contaminant accumulations in field-grown rice. For most target compounds, all three uptake pathways (root, foliar gas, and foliar particle uptakes) contributed substantially to the overall contaminant burden in rice. Compounds with lower octanol-water partition coefficients (Kow) were more readily translocated from roots to leaves, and compounds with higher octanol-air partition coefficients (Koa) tended to enter rice leaves mostly through particle deposition. Most compounds were mostly stored in the inner leaves (55.3-98.2 %), whereas the relatively volatile compounds were more readily absorbed by the waxy layer and then transferred to the inner leaves. Air particle desorption was a key process regulating foliar uptake of low-volatility compounds. The results can help us to better understand and predict the environmental fate of those contaminants, and develop more effective management strategies for reducing their human exposure through food ingestion.
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Oryza , Ácidos Ftálicos , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Oryza/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Ácidos Ftálicos/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/análisis , Organofosfatos/metabolismo , Ésteres/metabolismo , Monitoreo del AmbienteRESUMEN
Phthalate esters (PAEs), as a major plasticizer with multi-biotoxicity, are frequently detected in marine environments, and potentially affecting the survival of aquatic organisms. In the study, three typical PAEs (dimethyl phthalate [DMP], dibutyl phthalate [DBP] and di(2-ethylhexyl) phthalate [DEHP]) were selected to investigate the accumulation patterns and ecotoxicological effects on Mytilus coruscus (M. coruscus). In M. coruscus, the accumulation was DEHP>DBP>DMP, and the bioaccumulation in tissues was digestive glands>gills>gonads>muscles. Meanwhile, the activities of superoxide dismutase (SOD) and catalase (CAT) showed an activation-decrease-activation trend of stress, with more pronounced concentration effects. Glutathione reductase (GSH) activity was significantly increased, and its expression was more sensitive to be induced at an early stage. The metabolic profiles of the gonads, digestive glands and muscle tissues were significantly altered, and DEHP had a greater effect on the metabolic profiles of M. coruscus, with the strongest interference. PAEs stress for 7 d significantly altered the volatile components of M. coruscus, with potential implications for their nutritional value. This study provides a biochemical, metabolomic, and nutritional analysis of DMP, DBP, and DEHP toxic effects on M. coruscus from a multidimensional perspective, which provides support for ecotoxicological studies of PAEs on marine organisms. ENVIRONMENTAL IMPLICATION: Phthalate esters (PAEs), synthetic compounds from phthalic acid, are widespread in the environment, household products, aquatic plants, animals, and crops, posing a significant threat to human health. However, the majority of toxicological studies examining the effects of PAEs on aquatic organisms primarily focus on non-economic model organisms like algae and zebrafish. Relatively fewer studies have been conducted on marine organisms, particularly economically important shellfish. So, this study is innovative and necessary. This study provides a biochemical, metabolomic, and nutritional analysis of DMP, DBP, and DEHP toxic effects on mussels, and supports the ecotoxicology of PAEs on marine organisms.
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Mytilus , Ácidos Ftálicos , Plastificantes , Contaminantes Químicos del Agua , Animales , Ácidos Ftálicos/toxicidad , Ácidos Ftálicos/metabolismo , Mytilus/efectos de los fármacos , Mytilus/metabolismo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/metabolismo , Plastificantes/toxicidad , Plastificantes/metabolismo , Superóxido Dismutasa/metabolismo , Antioxidantes/metabolismo , Dietilhexil Ftalato/toxicidad , Dietilhexil Ftalato/metabolismo , Catalasa/metabolismo , Dibutil Ftalato/toxicidad , Dibutil Ftalato/metabolismo , Glutatión Reductasa/metabolismo , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Ésteres/metabolismo , Ésteres/toxicidad , Estrés Oxidativo/efectos de los fármacosRESUMEN
The concerning of plastic pollution in different ecosystems has been worsened by the widespread presence. Phthalate esters (PAEs), plasticizers found in everyday products, can migrate into the environment, especially into the oceans. Researches on their effects on cetaceans are still rare. Metabolomics helps assess perturbations induced by exposure to PAEs, which act as persistent endocrine disruptors. Four PAEs (dimethyl phthalate - DMP, diethyl phthalate - DEP, dibutyl phthalate - DBP, and di(2-ethylhexyl phthalate - DEHP) were analyzed, along with cholesterol and fatty acid profiles of P. blainvillei's blubber samples collected in southern Brazil. The study reveals pervasive contamination by PAEs - especially DEHP, present in all samples - with positive correlations between DEP content and animal size and weight, as well as between the DEHP amount and the C17:1 fatty acid. These findings will be relevant to conservation efforts aimed at this threatened species and overall marine ecosystems.
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Delfines , Monitoreo del Ambiente , Ésteres , Metaboloma , Ácidos Ftálicos , Contaminantes Químicos del Agua , Animales , Brasil , Ácidos Ftálicos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Ésteres/análisis , Ésteres/metabolismo , Delfines/metabolismo , Tejido Adiposo/metabolismo , Dietilhexil Ftalato/metabolismo , Plastificantes , Disruptores Endocrinos/análisis , Masculino , Femenino , Dibutil FtalatoRESUMEN
Phthalate isomers are key intermediates in the biodegradation of pollutants including waste polyethylene terephthalate (PET) plastics and plasticizers. So far, an increasing number of phthalate isomer-degrading strains have been isolated, and their degradation pathways show significant diversity. In this paper, we comprehensively review the current status of research on the degrading bacteria, degradation characteristics, aerobic and anaerobic degradation pathways, and degradation genes (clusters) of phthalate isomers, and discuss the current shortcomings and challenges. Moreover, the degradation process of phthalate isomers produces many important aromatic precursor molecules, which can be used to produce higher-value derivative chemicals, and the modification of their degradation pathways holds good prospects. Therefore, this review also highlights the current progress made in modifying the phthalate isomer degradation pathway and explores its potential for high-value applications.
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Bacterias , Biodegradación Ambiental , Ácidos Ftálicos , Ácidos Ftálicos/metabolismo , Bacterias/metabolismo , Bacterias/genética , Bacterias/clasificación , Isomerismo , Plastificantes/metabolismo , Contaminantes Ambientales/metabolismo , Redes y Vías Metabólicas , Tereftalatos Polietilenos/metabolismo , Tereftalatos Polietilenos/químicaRESUMEN
The mono(2-hydroxyethyl) terephthalate hydrolase (MHETase) from Ideonella sakaiensis carries out the second step in the enzymatic depolymerization of poly(ethylene terephthalate) (PET) plastic into the monomers terephthalic acid (TPA) and ethylene glycol (EG). Despite its potential industrial and environmental applications, poor recombinant expression of MHETase has been an obstacle to its industrial application. To overcome this barrier, we developed an assay allowing for the medium-throughput quantification of MHETase activity in cell lysates and whole-cell suspensions, which allowed us to screen a library of engineered variants. Using consensus design, we generated several improved variants that exhibit over 10-fold greater whole-cell activity than wild-type (WT) MHETase. This is revealed to be largely due to increased soluble expression, which biochemical and structural analysis indicates is due to improved protein folding.
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Burkholderiales , Burkholderiales/enzimología , Burkholderiales/genética , Burkholderiales/metabolismo , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/química , Hidrolasas/metabolismo , Hidrolasas/genética , Hidrolasas/química , Solubilidad , Tereftalatos Polietilenos/metabolismo , Tereftalatos Polietilenos/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Ingeniería de Proteínas/métodos , Pliegue de Proteína , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Modelos MolecularesRESUMEN
Phthalate esters (PAEs) are widely used as plasticizers and cause serious complex pollution problem in environment. Thus, strains with efficient ability to simultaneously degrade various PAEs are required. In this study, a newly isolated strain Rhodococcus sp. AH-ZY2 can degrade 500 mg/L Di-n-octyl phthalate completely within 16 h and other 500 mg/L PAEs almost completely within 48 h at 37 °C, 180 rpm, and 2 % (v/v) inoculum size of cultures with a OD600 of 0.8. OD600 = 0.8, 2 % (v/v). Twenty genes in its genome were annotated as potential esterase and four of them (3963, 4547, 5294 and 5359) were heterogeneously expressed and characterized. Esterase 3963 and 4547 is a type I PAEs esterase that hydrolyzes PAEs to phthalate monoesters. Esterase 5294 is a type II PAEs esterase that hydrolyzes phthalate monoesters to phthalate acid (PA). Esterase 5359 is a type III PAEs esterase that simultaneously degrades various PAEs to PA. Molecular docking results of 5359 suggested that the size and indiscriminate binding feature of spacious substrate binding pocket may contribute to its substrate versatility. AH-ZY2 is a potential strain for efficient remediation of PAEs complex pollution in environment. It is first to report an esterase that can efficiently degrade mixed various PAEs.