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1.
ChemMedChem ; : e202400326, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38993102

RESUMO

Proteolysis-targeting chimeras (PROTACs) have emerged as a promising technology for inducing targeted protein degradation by leveraging the intrinsic ubiquitin-proteasome system (UPS). While the potential druggability of PROTACs toward undruggable proteins has accelerated their rapid development and the wide-range of applications across diverse disease contexts, off-tissue effect and side-effects of PROTACs have recently received attentions to improve their efficacy. To address these issues, spatial or temporal target protein degradation by PROTACs has been spotlighted. In this review, we explore chemical strategies for modulating protein degradation in a cell type-specific (spatio-) and time-specific (temporal-) manner, thereby offering insights for expanding PROTAC applications to overcome the current limitations of target protein degradation strategy.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38993132

RESUMO

Endothelial dysfunction (ED) serves as the pathological basis for various cardiovascular diseases. Guanosine triphosphate cyclopyrrolone 1 (GCH1) emerges as a pivotal protein in sustaining nitric oxide (NO) production within endothelial cells, yet it undergoes degradation under oxidative stress, contributing to endothelial cell dysfunction. Citronellal (CT), a monoterpenoid, has been shown to ameliorate endothelial dysfunction induced by in atherosclerosis rats. However, whether CT can inhibit the degradation of GCH1 protein is not clear. It has been reported that ubiquitination may play a crucial role in regulating GCH1 protein levels and activities. However, the specific E3 ligase for GCH1 and the molecular mechanism of GCH1 ubiquitination remains unclear. Using data-base exploration analysis, we find that the levels of the E3 ligase Smad-ubiquitination regulatory factor 2 (Smurf2) negatively correlate with those of GCH1 in vascular tissues and HUVECs. We observe that Smurf2 interacts with GCH1 and promotes its degradation via the proteasome pathway. Interestingly, ectopic Smurf2 expression not only decreases GCH1 levels but also reduces cell proliferation and reactive oxygen species (ROS) levels, mostly because of increased GCH1 accumulation. Furthermore, we identify BH 4/eNOS as downstream of GCH1. Taken together, our results indicate that CT can obviously improve vascular endothelial injury in Type 1 diabetes mellitus (T1DM) rats and reverse the expressions of GCH1 and Smurf2 proteins in aorta of T1DM rats. Smurf2 promotes ubiquitination and degradation of GCH1 through proteasome pathway in HUVECs. We conclude that the Smurf2-GCH1 interaction might represent a potential target for improving endothelial injury.

3.
Animals (Basel) ; 14(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38998042

RESUMO

For protein evaluation of feedstuffs for ruminants, the Streptomyces griseus protease test provides a solely enzymatic method for estimating ruminal protein degradation. Since plant proteins are often structured in carbohydrate complexes, the use of carbohydrase during the test might improve its accuracy. It is advisable to co-incubate protease and carbohydrase, risking that the carbohydrase activity is reduced under the influence of the protease. The present study was conducted to investigate this impact by using α-amylase or the multi-enzyme complex Viscozym® L as carbohydrase. The detection of active protease was determined fluorescence photometrically using internally quenched fluorogenic substrates (IQFS). Cellulose, pectin, and starch degradation were determined spectrophotometrically using 3,5-dinitro salicylic acid as a colorimetric agent. The Streptomyces griseus protease mixture proved to be active for the selected IQFS immediately after the start of measurements (p < 0.05). Starch hydrolysis catalyzed by α-amylase or Viscozym® L, respectively, was decreased by co-incubation with protease mixture by maximal 3% or 37%, respectively, at 5 h incubation time (p > 0.05). Pectin and cellulose hydrolysis catalyzed by Viscozym® L, respectively, was not significantly influenced by co-incubation with a protease mixture (p > 0.05). Although a decrease in carbohydrase activity during co-incubation with Streptomyces griseus protease occurred, it was only numerical and might be counteracted by an adapted carbohydrase activity.

4.
Int J Mol Sci ; 25(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38999979

RESUMO

This study presents a pioneering synthesis of a direct Z-scheme Y2TmSbO7/GdYBiNbO7 heterojunction photocatalyst (YGHP) using an ultrasound-assisted hydrothermal synthesis technique. Additionally, novel photocatalytic nanomaterials, namely Y2TmSbO7 and GdYBiNbO7, were fabricated via the hydrothermal fabrication technique. A comprehensive range of characterization techniques, including X-ray diffractometry, Fourier-transform infrared spectroscopy, Raman spectroscopy, UV-visible spectrophotometry, X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray energy-dispersive spectroscopy, fluorescence spectroscopy, photocurrent testing, electrochemical impedance spectroscopy, ultraviolet photoelectron spectroscopy, and electron paramagnetic resonance, was employed to thoroughly investigate the morphological features, composition, chemical, optical, and photoelectric properties of the fabricated samples. The photocatalytic performance of YGHP was assessed in the degradation of the pesticide acetochlor (AC) and the mineralization of total organic carbon (TOC) under visible light exposure, demonstrating eximious removal efficiencies. Specifically, AC and TOC exhibited removal rates of 99.75% and 97.90%, respectively. Comparative analysis revealed that YGHP showcased significantly higher removal efficiencies for AC compared to the Y2TmSbO7, GdYBiNbO7, or N-doped TiO2 photocatalyst, with removal rates being 1.12 times, 1.21 times, or 3.07 times higher, respectively. Similarly, YGHP demonstrated substantially higher removal efficiencies for TOC than the aforementioned photocatalysts, with removal rates 1.15 times, 1.28 times, or 3.51 times higher, respectively. These improvements could be attributed to the Z-scheme charge transfer configuration, which preserved the preferable redox capacities of Y2TmSbO7 and GdYBiNbO7. Furthermore, the stability and durability of YGHP were confirmed, affirming its potential for practical applications. Trapping experiments and electron spin resonance analyses identified active species generated by YGHP, namely •OH, •O2-, and h+, allowing for comprehensive analysis of the degradation mechanisms and pathways of AC. Overall, this investigation advances the development of efficient Z-scheme heterostructural materials and provides valuable insights into formulating sustainable remediation strategies for combatting AC contamination.


Assuntos
Luz , Toluidinas , Catálise , Toluidinas/química , Fotólise , Poluentes Químicos da Água/química , Processos Fotoquímicos , Espectroscopia Fotoeletrônica , Gadolínio/química
5.
Int J Mol Sci ; 25(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000062

RESUMO

The present work focuses on the synthesis of a vanadium nitride (VN)/carbon nanocomposite material via the thermal decomposition of vanadyl phthalocyanine (VOPC). The morphology and chemical structure of the synthesized compounds were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoemission spectroscopy (XPS). The successful syntheses of the VOPC and non-metalated phthalocyanine (H2PC) precursors were confirmed using FTIR and XRD. The VN particles present a needle-like morphology in the VN synthesized by the sol-gel method. The morphology of the VN/C composite material exhibited small clusters of VN particles. The XRD analysis of the thermally decomposed VOPC indicated a mixture of amorphous carbon and VN nanoparticles (VN(TD)) with a cubic structure in the space group FM-3M consistent with that of VN. The XPS results confirmed the presence of V(III)-N bonds in the resultant material, indicating the formation of a VN/C nanocomposite. The VN/C nanocomposite synthesized through thermal decomposition exhibited a high carbon content and a cluster-like distribution of VN particles. The VN/C nanocomposite was used as an anode material in LIBs, which delivered a specific capacity of 307 mAh g-1 after 100 cycles and an excellent Coulombic efficiency of 99.8 at the 100th cycle.


Assuntos
Carbono , Nanocompostos , Nanocompostos/química , Carbono/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Indóis/química , Vanádio/química , Compostos de Vanádio/química , Espectroscopia Fotoeletrônica
6.
ACS Nano ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995623

RESUMO

Given the pressing depletion of lithium resources, sodium-ion batteries (SIBs) stand out as a cost-effective alternative for energy storage solutions in the near future. Layered transition metal oxides (LTMOs) emerge as the leading cathode materials for SIBs due to their superior specific capacities and abundant raw materials. Nonetheless, achieving long-term stability in LTMOs for SIBs remains a challenge due to the inevitable structural degradation during charge-discharge cycles. The complexity and diversity of cation configurations/superstructures within the transition metal layers (TMO2) further complicate the understanding for newcomers. Therefore, it is critical to summarize and discuss the factors leading to structural degradation and the available strategies for enhancing LTMOs' stability. In this review, the cationic configurations of TMO2 layers are introduced from a crystallographic perspective. It then identifies and examines four key factors responsible for structural decay, alongside the impacts of various modification strategies. Finally, more effective and practical research approaches for investigating LTMOs have been proposed. The work aims to enhance the comprehension of the structural deterioration of LTMOs and facilitate a substantial improvement in their cycle life and energy density.

7.
PNAS Nexus ; 3(7): pgae271, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39010939

RESUMO

Aflatoxins (AFs) are carcinogenic fungal toxins contaminating up to 25% of the global food supply. Over half of the world's population is exposed to unmonitored levels of AFs, mostly aflatoxin B1 (AFB1). Despite numerous efforts over the past 60 years, there are no solutions to remove AFs safely from food. Here, we present a safe and effective AF-degrading product called "D-Tox", a filtered culture broth of Aspergillus oryzae grown in a food-grade liquid medium. When 5 ppm of AFB1 is added to D-Tox, ∼90% is degraded at 48 and 24 hr at room temperature and 50°C, respectively. Moreover, when varying amounts (0.1 ppm ∼ 100 ppm) of AFB1 are added to D-Tox at 100°C, over 95% of AFB1 is degraded in 1 hr, suggesting a nonenzymatic process. Examining degradation of 100 ppm AFB1 reveals that aflatoxin D1 (AFD1) is the major transient degradant of AFB1, indicating that degradation occurs irreversibly by lactone ring hydrolysis followed by decarboxylation. D-Tox further degrades AFD1 to unknown fragmented products. Importantly, the practical application of D-Tox is also demonstrated, as more than 70% of AFB1 is degraded when wheat, corn, and peanuts naturally contaminated with high levels of AFB1 (0.3 ∼ 4.5 ppm) are boiled in D-Tox for 1 hr. Additionally, D-Tox can degrade other lactone-ring containing mycotoxins, including patulin and ochratoxin. D-Tox exhibits no cytotoxicity under the conditions tested in MCF-7 breast cancer cell lines. In summary, D-Tox is a safe and effective AF-detoxifying product that can enhance global food safety.

8.
Sci Total Environ ; : 174590, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38981546

RESUMO

The Etoliko Lagoon in western Greece has experienced extensive human modification since the 20th century, both on the surrounding land and in the aquatic environment. To examine human impacts and disentangle climatic from anthropogenic changes, we present a suite of biomarker records that span the past two centuries (~1790-2011). Specifically, we use terrigenous (n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and phytosterols) and aquatic (dinosterol, brassicasterol, cholesterol, and stigmasterol) biomarkers to document changes in nutrient inputs, combustion, and algal productivity. During most of the 19th and 20th centuries, aquatic communities respond to temperature, forced mainly by solar irradiance and volcanic activity, and precipitation, controlled largely by summer and winter North Atlantic Oscillation (NAO) patterns that determine freshwater runoff. PAHs illustrate the acceleration of coal combustion during the 1800s, and declining concentrations since the 1950s correspond to the implementation of emission controls and reductions in rainfall that likely inhibited PAH transport. As human pressures increased in the late 1900s and water column anoxia grew, the absence of a clear human waste and eutrophication signal suggests that other factors also contributed to limited oxygen availability. Overall, environmental degradation of the late 20th and early 21st centuries is clear and can be attributed to a combination of especially arid conditions and human interferences that altered lagoon hydrography, trophic state, and aquatic community composition.

9.
Sci Total Environ ; : 174445, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38981547

RESUMO

Biobased biodegradable polymers (BBP) derived from different renewable resources are commonly considered as attractive alternative to petroleum-based polymers, such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), etc. It is because they can address the issues of serious environmental problems resulted from accumulation of plastic wastes. In the review current methods of obtaining of most abundant BBP, polylactic acid (PLA) and polyhydroxybutyrate (PHB), have been studied with an emphasis on the toxicity of compounds used for their production and additives improving consumer characteristics of PLA and PHB based market products. Substantial part of additives was the same used for traditional polymers. Analysis of the data on the response of different organisms and plants on exposure to these materials and their degradation products confirmed the doubts about real safety of BBP. Studies of safer additives are scarce and are of vital importance. Meanwhile, technologies of recycling of traditional petroleum-based polymers were shown to be well-developed, which cannot be said about PLA or PHB based polymers, and their blends with petroleum-based polymers. Therefore, development of more environmentally friendly components and sustainable technologies of production are necessary before following market expansion of biobased biodegradable products.

10.
Sci Total Environ ; 947: 174384, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964389

RESUMO

The characteristics of lake dissolved organic matter (DOM) pool and lake ecosystem interact, and studying the responses between sediment DOM characteristics and lake ecosystem changes may shed light on the inherent connection between ecosystem evolution and carbon biogeochemical cycles. Lakes in cold and arid regions are sensitive to changes and accumulate large amounts of carbon as DOM, which may provide a window into more explicit relationships between ecosystem evolution and changes in sediment DOM characteristics in time dimension. However, considerable blind spots exist in the responses between the sediment DOM and ecosystem evolution on time scale and the underlying mechanisms. In this study, multiple approaches were combined to investigate the relationship between the variation trend of sediment DOM characteristics and the evolution of fragile lake ecosystems across three different lake ecosystems in cold and arid regions of China. A strong positive relationship between sediment DOM stabilities, especially humification, and ecosystem degradation was found, consistent for the three lakes. Ultra-high-resolution mass spectrometry and structural equation modeling revealed that the changes of ecosystems affected sediment DOM stability through direct pathways (0.24), such as the contents of terrestrial DOM in lake DOM pool, and indirect pathways, including algae-mediated (0.43) and salinity-mediated pathways (0.22), which all increased the contents of refractory DOM in the lake DOM pool and sediments. Based on the fact that DOM stability changes could act on the ecosystem in turn, a possible positive feedback mechanism between ecosystem degradation and increased DOM stability was further inferred. These results suggested that the continuous increased stability of sediment DOM in may implies ecosystem degradation of lakes in the cold and arid regions. This study provides a new perspective for recognizing ecosystem evolution through sediment DOM and improves the understanding of the interaction of lake ecosystem evolution and the biogeochemical cycle of DOM.

11.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000226

RESUMO

E3 ubiquitin ligases (UBLs), as enzymes capable of specifically recognizing target proteins in the process of protein ubiquitination, play crucial roles in regulating responses to abiotic stresses such as drought, salt, and temperature. Abscisic acid (ABA), a plant endogenous hormone, is essential to regulating plant growth, development, disease resistance, and defense against abiotic stresses, and acts through a complex ABA signaling pathway. Hormone signaling transduction relies on protein regulation, and E3 ubiquitin ligases play important parts in regulating the ABA pathway. Therefore, this paper reviews the ubiquitin-proteasome-mediated protein degradation pathway, ABA-related signaling pathways, and the regulation of ABA-signaling-pathway-related genes by E3 ubiquitin ligases, aiming to provide references for further exploration of the relevant research on how plant E3 ubiquitin ligases regulate the ABA pathway.


Assuntos
Ácido Abscísico , Transdução de Sinais , Ubiquitina-Proteína Ligases , Ubiquitina-Proteína Ligases/metabolismo , Ácido Abscísico/metabolismo , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Ubiquitinação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo
12.
Biol Aujourdhui ; 218(1-2): 41-54, 2024.
Artigo em Francês | MEDLINE | ID: mdl-39007776

RESUMO

The review is focused on recent drug discovery advances based on targeted protein degradation strategies. This new area of research has exploded leading to the development of potential drugs useful in a large variety of human diseases. They first target disease relevant proteins difficult to counteract with other classical strategies and extend now to aggregates, organelles, nucleic acids or lipidic droplets. These degraders engaged either the ubiquitin-proteasome system for PROTACs and molecular glues (first generation), or the lysosomal system via endosome-lysosome degradation (LYTACs) and autophagy-lysosome degradation (ATTEC, AUTAC, AUTOTAC) (following generations of degraders). PROTACs have expanded from the orthodox heterobifunctional ones to new derivatives such as homo-PROTACs, pro-PROTACs, CLIPTACs, HaloPROTACs, PHOTOTACs, Bac-PROTACs, AbTACs, ARN-PROTACs. The small molecular-weight molecular glues induce the formation of new ternary complexes which implicate the targeted protein and an ubiquitin ligase E3 allowing the protein ubiquinitation followed by its proteasomal degradation. Lysosomal degraders (LYTAC, ATTEC, AUTAC, AUTOTAC) specifically recognize extracellular and membrane proteins or dysfunctional organelles and transport them into lysosomes where they are degraded. They overcome the limitations observed with proteasomal degradations induced by PROTAC and molecular glues and demonstrate their potential to treat human diseases, especially neurodegenerative ones. Pharmaceutical companies are engaged at the world level to develop these new potential drugs targeting cancers, immuno-inflammatory and neurodegenerative diseases as well as a variety of other ones. Efficiency and risks for these novel therapeutic strategies are discussed.


Title: Induction de proximité et dégradation de cibles thérapeutiques par les nouveaux dégradeurs : quels concepts, quels développements, quel futur ? Abstract: La recherche dans le domaine de la dégradation ciblée des protéines s'est considérablement développée conduisant à l'élaboration de nouveaux outils chimiques à visée thérapeutique, les dégradeurs, potentiellement utiles dans diverses pathologies. Une grande variété d'objets à dégrader appartenant à divers compartiments intra- ou extracellulaires (protéines, complexes ou agrégats, organelles, acides nucléiques, gouttelettes lipidiques) a été ciblée à l'aide de ligands déjà existants, d'autres restent à découvrir. Les molécules de première génération, PROTAC et colles moléculaires, utilisent le système ubiquitine-protéasome pour détruire spécifiquement des protéines pathogéniques, certaines considérées jusqu'à présent comme inaccessibles en tant que cibles thérapeutiques. Au cours des cinq dernières années, ont été développés de nouveaux types de PROTAC hétéro-bifonctionnels comme les homo-PROTAC, pro-PROTAC, CLIPTAC, HaloPROTAC, PHOTOTAC, Bac-PROTAC, mais aussi des PROTAC macromoléculaires comme les AbTAC et ARN-PROTAC. Du fait de la grande diversité des substrats dégradés par les lysosomes, de nouveaux dégradeurs impliquant deux voies distinctes ont été ensuite produits : les chimères LYTAC pour la voie endosome-lysosome et les chimères ATTEC, AUTAC et AUTOTAC pour la voie autophagie-lysosome, augmentant ainsi considérablement le champ d'action des dégradeurs. Ces nouvelles molécules reconnaissent spécifiquement des protéines et/ou des organelles et permettent leur transport dans les lysosomes où ils sont dégradés. Les succès obtenus, que ce soit par dégradation protéasomale ou lysosomale pour plusieurs dizaines de dégradeurs (preuves de concepts et études cliniques en cours), expliquent l'intérêt quasi mondial des industries pharmaceutiques pour ces nouvelles molécules. Les challenges posés par leur développement et leur utilisation en clinique sont discutés.


Assuntos
Lisossomos , Proteólise , Humanos , Proteólise/efeitos dos fármacos , Lisossomos/metabolismo , Animais , Proteínas/metabolismo , Descoberta de Drogas/tendências , Descoberta de Drogas/métodos , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/fisiologia , Terapia de Alvo Molecular/métodos , Terapia de Alvo Molecular/tendências , Autofagia/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-39007977

RESUMO

This current study explored the effect of pyrite on the treatment of chlorophenolic compounds (CP) by Fenton process with micron-sized zero-valent iron (ZVI) as the catalyst. The experiments were conducted in batch reactors with 100 mg L-1 CP, 0-0.02 M H2O2, and variable pyrite and ZVI doses (0-1 g L-1). Our findings show that while the reactor with 1 g L-1 ZVI as the only catalyst achieved only 10% CP removal efficiency due to rapid ZVI surface passivation and ZVI particle aggregation, the CP removal efficiency increased with increasing pyrite dose and reached 100% within couple of minutes in reactors with 0.8 g L-1 pyrite and 0.2 g L-1 ZVI. The CP removal was mainly driven by the oxidative treatment of CPs with some strong radicals such as hydroxyl radicals (•OH) while the adsorption onto the catalyst surface was only responsible for 10 to 25% of CP removals, depending on the type of CP studied. The positive impact of pyrite on CP removal by the ZVI/H2O2 system could be attributed to the ability of pyrite to (1) create an acidic environment for optimum Fenton process, (2) provide support material for ZVI to minimize ZVI particle agglomeration, and (3) stimulate iron redox cycling for improved surface site generation. Following oxidative Fenton treatment, the degradation intermediate products of CPs, including some aromatic compounds (benzoquinone, hydroquinone, etc.) and organic acids (e.g., acetic acid), became more biodegradable in comparison to their mother compounds. Overall, the treatment systems with a mixture of ZVI and pyrite as catalyst materials could offer a suitable cost-effective technology for the treatment of wastewater containing biologically non- or low-degradable toxic compounds such as chlorophenols.

14.
Artigo em Inglês | MEDLINE | ID: mdl-39008233

RESUMO

Bismuth-doped metal oxides exhibit favourable photocatalytic features when exposed to both sunlight and UV light. In this approach, Bi0/TiO2 and Bi+3/TiO2 photocatalysts were prepared and their structural and optical properties are analysed using various characterization techniques. These developed photocatalysts were further tested for the photocatalytic elimination of Nitrobenzene in UV light and sunlight and compared with the performance of bare TiO2. The catalyst Bi+3/TiO2 performed better in UV light with 72.31% degradation, and 4.74 × 10-6 mol.litre-1.min-1 initial rate of reaction. However, when exposed to sunlight, Bi0/TiO2 outperformed with 73.85% degradation, and 4.63 × 10-6 mol.min-1 initial rate of reaction. This significant increase in photocatalytic activity of Bi0/TiO2 under sunlight could be accredited to increased light harvesting and enhanced efficiency in charge carrier separation, both of which were made possible by bismuth-induced surface plasmon resonance.

15.
Sensors (Basel) ; 24(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39001059

RESUMO

This paper presents an innovative technique, Advanced Predictor of Electrical Parameters, based on machine learning methods to predict the degradation of electronic components under the effects of radiation. The term degradation refers to the way in which electrical parameters of the electronic components vary with the irradiation dose. This method consists of two sequential steps defined as 'recognition of degradation patterns in the database' and 'degradation prediction of new samples without any kind of irradiation'. The technique can be used under two different approaches called 'pure data driven' and 'model based'. In this paper, the use of Advanced Predictor of Electrical Parameters is shown for bipolar transistors, but the methodology is sufficiently general to be applied to any other component.

16.
Bioorg Chem ; 151: 107629, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003942

RESUMO

Melanin is a complex brown pigment, primarily responsible for the skin pigmentation. Therefore, cosmetic industries have always been in search of potent oxidative enzymes useful for melanin degradation, and to promise a fair complexion after using their products. In the present study, lignin peroxidase from Pseudomonas fluorescence LiP-RL5 isolate has been immobilized on super-paramagnetic nanoparticles to enhance its stability and reusability. The chitosan coated enzyme-nanomaterial complex (LiP@MFO-Chit) showed higher melanin decolorization (47.30 ± 2.3 %) compared to the graphene oxide coated nanoparticles (LiP@MFO-GO) (41.60 ± 1.6 %). Synthesized enzyme nanoparticle complexes showed microbicidal effect on skin infection causing pathogen, Pantoea agglomerans with an inhibitory zone of 6.0 ± 0.9 mm and 250 µg/100 µl minimum inhibitory concentration, and a 7.0 ± 1.5 mm zone and 170 µg/100 µl MIC for LiP@MFO-GO and LiP@MFO-Chit, respectively. Antioxidant potential of LiP@MFO-Chit and LiP@MFO-GO nano-conjugates showed a substantial DPPH scavenging activity of 75.7 % and 88.3 %, respectively. Therefore, LiP-nanoparticle hybrid complexes analyzed in this study are not only effective as skin whitening agents but they are potential molecules against various microbial skin infections as well as useful for different other biomedical applications like biorefinery, drug delivery, and dermatology, etc.

17.
Mar Pollut Bull ; 206: 116710, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39004058

RESUMO

The deep-water area in the central Bohai Sea (BS) serves as a spawning ground and nursery for fish, shrimp, and crabs. Frequent hypoxia will affect the ecological environment in the central BS. Data from an on-site investigation of the central BS in the spring and summer of 2022 were used to analyze the relevant factors generating the occurrence of hypoxia in the central BS through the eutrophication index E, apparent oxygen consumption (AOU), and Spearman correlation. The hypoxia area was largely distributed in the study area's deep water section, and stratification was the main cause of hypoxia at the bottom. Organic matter mineralization, degradation, and biological respiration further exacerbated the hypoxia. In the summer of 2022, temperature stratification was the dominant factor influencing hypoxia.

18.
Fungal Genet Biol ; : 103913, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004162

RESUMO

Schizophyllum commune is a mushroom-forming fungus notable for its distinctive fruiting bodies with split gills. It is used as a model organism to study mushroom development, lignocellulose degradation and mating type loci. It is a hypervariable species with considerable genetic and phenotypic diversity between the strains. In this study, we systematically phenotyped 16 dikaryotic strains for aspects of mushroom development and 18 monokaryotic strains for lignocellulose degradation. There was considerable heterogeneity among the strains regarding these phenotypes. The majority of the strains developed mushrooms with varying morphologies, although some strains only grew vegetatively under the tested conditions. Growth on various carbon sources showed strain-specific profiles. The genomes of seven monokaryotic strains were sequenced and analyzed together with six previously published genome sequences. Moreover, the related species Schizophyllum fasciatum was sequenced. Although there was considerable genetic variation between the genome assemblies, the genes related to mushroom formation and lignocellulose degradation were well conserved. These sequenced genomes, in combination with the high phenotypic diversity, will provide a solid basis for functional genomics analyses of the strains of S. commune.

19.
Sci Total Environ ; : 174722, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004358

RESUMO

Communities in stream ecosystems often respond asymmetrically to increase and release of stressors, as indicated by slow and incomplete recovery. The Asymmetric Response Concept (ARC) posits that this is due to a shift in the relative importance of three mechanisms: tolerance, dispersal, and biotic interactions. In complex natural communities, these mechanisms may produce alternative outcomes through poorly understood indirect effects. To understand how the three mechanisms respond to different temporal stressor scenarios, we studied multiple scenarios using a stream food web model. We asked the following questions: Do groups of species decline as expected on the basis of individual tolerance rankings derived from laboratory experiments when they are embedded in a complex dynamic food web? Does the response of ecosystem function match that of communities? To address these questions, we aggregated data on individual tolerances at the level of functional groups and studied how single and multiple stressors affect food web dynamics and nutrient cycling. Multiple stressor scenarios involved different intensities of salt and temperature increase. Functional groups exhibited a different relative tolerance ranking between the laboratory and dynamic food web contexts. Salt as a single stressor had only minor and transient effects at low level but led to the loss of one or more functional groups at high level. In contrast, high temperature, alone or in combination with salt, caused the loss of functional groups at all tested levels. Patterns often differed between the response of communities and ecosystem function. We discuss our findings with respect to the ARC.

20.
Sci Total Environ ; : 174554, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39004366

RESUMO

This study investigates P. ostreatus and A. bisporus biodegradation capacity of low density polyethylene (LDPE) oxidised to simulate environmental weathering. Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were used to analyse the degradation of LDPE treated with fungal cultures. Molecular implications of LDPE degradation by P. ostreatus and A. bisporus were evaluated by Reverse transcription followed by quantitative PCR (qRT-PCR) of lac, mnp and lip genes expression. After 90 days of incubation, FT-IR analysis showed, for both fungal treatments, an increasing in the intensity of peaks related to the asymmetric C-C-O stretching (1160 to 1000 cm-1) and the -OH stretching (3700 to 3200 cm-1) due to the formation of alcohols and carboxylic acid, indicating depolymerisation of LDPE. This was confirmed by the SEM analysis, where a widespread alteration of the surface morphology was observed for treated LDPE fragments. Results revealed that the exposure of P. ostreatus to oxidised LDPE treatment led to a significant increase in the expression of the lac6, lac7, lac9, lac10 and mnp2 genes, while A. bisporus showed an over-expression in lac2 and lac12 genes. The obtained results offer new perspectives for a biotechnological use of P. ostreatus and A. bisporus for plastic bioremediation.

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