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1.
Chin Herb Med ; 16(2): 204-213, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38706819

RESUMEN

Medicinal plants, as medicinal materials and important drug components, have been used in traditional and folk medicine for ages. However, being sessile organisms, they are seriously affected by extreme environmental conditions and abiotic stresses such as salt, heavy metal, temperature, and water stresses. Medicinal plants usually produce specific secondary metabolites to survive such stresses, and these metabolites can often be used for treating human diseases. Recently, medicinal plants have been found to partner with endophytic fungi to form a long-term, stable, and win-win symbiotic relationship. Endophytic fungi can promote secondary metabolite accumulation in medicinal plants. The close relationship can improve host plant resistance to the abiotic stresses of soil salinity, drought, and extreme temperatures. Their symbiosis also sheds light on plant growth and active compound production. Here, we show that endophytic fungi can improve the host medicinal plant resistance to abiotic stress by regulating active compounds, reducing oxidative stress, and regulating the cell ion balance. We also identify the deficiencies and burning issues of available studies and present promising research topics for the future. This review provides guidance for endophytic fungi research to improve the ability of medicinal plants to resist abiotic stress. It also suggests ideas and methods for active compound accumulation in medicinal plants and medicinal material development during the response to abiotic stress.

2.
Bioorg Chem ; 147: 107418, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703441

RESUMEN

A key approach in developing green chemistry involves converting solar energy into chemical energy of biomolecules through photocatalysis. Photocatalysis can facilitate the regeneration of nicotinamide cofactors during redox processes. Nicotinamide cofactor biomimetics (NCBs) are economical substitutes for natural cofactors. Here, photocatalytic regeneration of NADH and reduced NCBs (NCBsred) using graphitic carbon nitride (g-C3N4) was developed. The process involves g-C3N4 as the photocatalyst, Cp*Rh(bpy)H2O2+ as the electron mediator, and Triethanolamine as the electron donor, facilitating the reduction of NAD+ and various oxidative NCBs (NCBsox) under light irradiation. Notably, the highest reduction yield of 48.32 % was achieved with BANA+, outperforming the natural cofactor NAD+. Electrochemical analysis reveals that the reduction efficiency and capacity of cofactors relies on their redox potentials. Additionally, a coupled photo-enzymatic catalysis system was explored for the reduction of 4-Ketoisophorone by Old Yellow Enzyme XenA. Among all the NCBsox and NAD+, the highest conversion ratio of over 99 % was obtained with BANA+. After recycled for 8 times, g-C3N4 maintained over 93.6 % catalytic efficiency. The photocatalytic cofactor regeneration showcases its outstanding performance with NAD+ as well as NCBsox. This work significantly advances the development of photocatalytic cofactor regeneration for artificial cofactors and its potential application.


Asunto(s)
Biocatálisis , Oxidación-Reducción , Procesos Fotoquímicos , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Estructura Molecular , NAD/química , NAD/metabolismo , Biomimética , Niacinamida/química , Niacinamida/metabolismo , Compuestos de Nitrógeno/química , Grafito
3.
Environ Res ; 251(Pt 1): 118389, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38460661

RESUMEN

Phytoremediation has emerged as a common technique for remediating Cd pollution in farmland soil. Moreover, phosphorus, an essential element for plants, can alter the pectin content of plant cell walls and facilitate the accumulation of Cd in plant tissues, thereby enhancing phytoremediation efficiency. Therefore, pot experiments were conducted in order to investigate the effect of phosphorus levels on Cd extraction, phosphorus transformation and phosphorus-related genes during phytoremediation. The results revealed that an optimal application of suitable phosphate fertilizers elevated the soil's pH and electrical conductivity (EC), facilitated the conversion of soil from insoluble phosphorus into available forms, augmented the release of pertinent enzyme activity, and induced the expression of phosphorus cycling-related genes. These enhancements in soil conditions significantly promoted the growth of ryegrass. When applying phosphorus at a rate of 600 mg/kg, ryegrass exhibited plant height, dry weight, and chlorophyll relative content that were 1.27, 1.26, and 1.18 times higher than those in the control group (P0), while the Cd content was 1.12 times greater than that of P0. The potentially toxic elements decline ratio and bioconcentration factor were 42.86% and 1.17 times higher than those of P0, respectively. Consequently, ryegrass demonstrated the highest Cd removal efficiency under these conditions. Results from redundancy analysis (RDA) revealed a significant correlation among pH, total phosphorus, heavy metal content, phosphorus forms, soil enzyme activity, and phosphorus-related genes. In conclusion, this study suggests applying an optimal amount of suitable phosphate fertilizers can enhance restoration efficiency, leading to a reduction in soil Cd content and ultimately improving the safety of crop production in farmlands.

4.
Chemosphere ; 354: 141670, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462184

RESUMEN

UV/H2O2 has been used as an advanced oxidation process to remove organic micropollutants from drinking water. It is essential to quench residual H2O2 to prevent increased chlorine demand during chlorination/chloramination and within distribution systems. Granular activated carbon (GAC) filter can quench the residual oxidant and eliminate some of the dissolved organic matter. However, knowledge on the kinetics and governing factors of GAC quenching of residual H2O2 from UV/H2O2 and the mechanism underlying the enhancement of the process by HCO3- is limited. Therefore, this study aimed to analyse the kinetics and influential factors, particularly the significant impact of bicarbonate (HCO3-). H2O2 decomposition by GAC followed first-order kinetics, and the rate constants normalised by the GAC dosage (kn) were steady (1.6 × 10-3 L g-1 min-1) with variations in the GAC dosage and initial H2O2 concentration. Alkaline conditions favour H2O2 quenching. The content of basic groups exhibited a stronger correlation with the efficiency of GAC in quenching H2O2 than did the acidic groups, with their specific kn values being 8.9 and 2.4 min-1 M-1, respectively. The presence of chloride, sulfate, nitrate, and dissolved organic matter inhibited H2O2 quenching, while HCO3- promoted it. The interfacial hydroxyl radical (HO•) zones were visualised on the GAC surface, and HCO3- addition increased the HO• concentration. HCO3- increased the concentration of persistent free radicals (PFRs) on the GAC surface, which mainly contributed to HO• generation. A significant enhancement of HCO3- on H2O2 quenching by GAC was also verified in real water. This study revealed the synergistic mechanism of HCO3- and GAC on H2O2 quenching and presents the potential applications of residual H2O2 in the H2O2-based oxidation processes.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico/análisis , Peróxido de Hidrógeno/análisis , Bicarbonatos , Materia Orgánica Disuelta , Contaminantes Químicos del Agua/análisis , Oxidación-Reducción , Agua Potable/análisis , Cinética , Rayos Ultravioleta
5.
Cells ; 13(6)2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38534334

RESUMEN

Histone deacetylase 6 (HDAC6) plays a crucial role in the acetylation of non-histone proteins and is notably implicated in angiogenesis, though its underlying mechanisms were previously not fully understood. This study conducted transcriptomic and proteomic analyses on vascular endothelial cells with HDAC6 knockdown, identifying endoglin (ENG) as a key downstream protein regulated by HDAC6. This protein is vital for maintaining vascular integrity and plays a complex role in angiogenesis, particularly in its interaction with bone morphogenetic protein 9 (BMP9). In experiments using human umbilical vein endothelial cells (HUVECs), the pro-angiogenic effects of BMP9 were observed, which diminished following the knockdown of HDAC6 and ENG. Western blot analysis revealed that BMP9 treatment increased SMAD1/5/9 phosphorylation, a process hindered by HDAC6 knockdown, correlating with reduced ENG expression. Mechanistically, our study indicates that HDAC6 modulates ENG transcription by influencing promoter activity, leading to increased acetylation of transcription factor SP1 and consequently altering its transcriptional activity. Additionally, the study delves into the structural role of HDAC6, particularly its CD2 domain, in regulating SP1 acetylation and subsequently ENG expression. In conclusion, the present study underscores the critical function of HDAC6 in modulating SP1 acetylation and ENG expression, thereby significantly affecting BMP9-mediated angiogenesis. This finding highlights the potential of HDAC6 as a therapeutic target in angiogenesis-related processes.


Asunto(s)
Células Endoteliales , Factor 2 de Diferenciación de Crecimiento , Humanos , Histona Desacetilasa 6/metabolismo , Factor 2 de Diferenciación de Crecimiento/metabolismo , Endoglina/metabolismo , Fosforilación , Células Endoteliales/metabolismo , Angiogénesis , Proteómica , Factores de Transcripción/metabolismo
6.
Antioxid Redox Signal ; 40(1-3): 86-109, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37548532

RESUMEN

Significance: As a new important gas signaling molecule like nitric oxide (NO) and carbon dioxide (CO), hydrogen sulfide (H2S), which can be produced by endogenous H2S-producing enzymes through l-cysteine metabolism in mammalian cells, has attracted wide attention for long. H2S has been proved to play an important regulatory role in numerous physiological and pathophysiological processes. However, the deep mechanisms of those different functions of H2S still remain uncertain. A better understanding of the mechanisms can help us develop novel therapeutic strategies. Recent Advances: H2S can play a regulating role through various mechanisms, such as regulating epigenetic modification, protein expression levels, protein activity, protein localization, redox microenvironment, and interaction with other gas signaling molecules such as NO and CO. In addition to discussing the molecular mechanisms of H2S from the above perspectives, this article will review the regulation of H2S on common signaling pathways in the cells, including the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), mitogen-activated protein kinase (MAPK), Janus kinase (JAK)/signal transducer, and activator of transcription (STAT) signaling pathway. Critical Issues: Although there are many studies on the mechanism of H2S, little is known about its direct target molecules. This article will also review the existing reports about them. Furthermore, the interaction between direct target molecules of H2S and the downstream signaling pathways involved also needs to be clarified. Future Directions: An in-depth discussion of the mechanism of H2S and the direct target molecules will help us achieving a deeper understanding of the physiological and pathophysiological processes regulated by H2S, and lay a foundation for developing new clinical therapeutic drugs in the future. Innovation: This review focuses on the regulation of H2S on signaling pathways and the direct target molecules of H2S. We also provide details on the underlying mechanisms of H2S functions from the following aspects: epigenetic modification, regulation of protein expression levels, protein activity, protein localization, redox microenvironment, and interaction with other gas signaling molecules such as NO and CO. Further study of the mechanisms underlying H2S will help us better understand the physiological and pathophysiological processes it regulates, and help develop new clinical therapeutic drugs in the future. Antioxid. Redox Signal. 40, 86-109.


Asunto(s)
Gasotransmisores , Sulfuro de Hidrógeno , Animales , Sulfuro de Hidrógeno/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/fisiología , Gasotransmisores/metabolismo , Óxido Nítrico/metabolismo , Mamíferos/metabolismo
7.
Ultrason Sonochem ; 100: 106642, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37838531

RESUMEN

The fluctuation of dissolved oxygen is one of the primary cause of disruptions to the consistent operation of partial nitrification, and the level of dissolved oxygen is mainly controlled by the aeration rate. This study investigated the influence of ultrasonic treatment on the stability of partial nitrification of activated sludge under different aeration conditions. After being treated with ultrasound (energy density = 0.20 W·mL-1, treatment time = 10 min), partial nitrification process operated stably for 67 days, with the nitrite accumulation rate above 83.89 %. The effluent contained 42.50 mg·L-1 of nitrite, much higher than the control reactor (0.30 mg·L-1). The gap between the specific ammonia and nitrite oxidation rates widened continuously as the aeration rate increased, and nitrite-oxidizing bacteria activity did not recover even under conditions with a very high oxygen content. Further analysis showed that ultrasonic treatment had obvious stripping effect on excess extracellular polymeric substances (EPS), especially loosely bound EPS and protein. Additionally, long-term ultrasonic treatment promoted the enrichment of Nitrosomonas and strongly inhibited Nitrotoga. Based on these findings, it appears that under conditions of high aeration rate, ultrasound effectively suppress the recovery of Nitrotoga activity and improve the stability of partial nitrification.


Asunto(s)
Reactores Biológicos , Nitrificación , Reactores Biológicos/microbiología , Nitritos , Aguas del Alcantarillado/microbiología , Oxígeno , Oxidación-Reducción , Nitrógeno
8.
Heliyon ; 9(9): e19777, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809971

RESUMEN

In this study, the co-digestion system with Navel orange residues (NOR) and Waste activated sludge (WAS) was established, by pre-treating the NOR and setting different volatile solids (VS) ratios of NOR to WAS to motivate the production of volatile fatty acids (VFA). The pre-treatment method (pH 7 and temperature 70 °C) promoted the release of dissolved organic matter, and the concentration of soluble chemical oxygen demand (SCOD) increased by 45.56% compared with the untreated group (pH 3 and temperature 20 °C). In the co-digestion system, the highest VFA yield (5716.69 mg/L) was obtained at VS ratio of 2. When the VS ratio was increased to 4, the imbalance in proportions of carbon and nitrogen affected VFA production, and the high concentration of essential oils (EO) present in the NOR inhibited the methane production; the cumulative yield of methane gas decreased by 24.10% compared with the yield obtained when the VS ratio was 2. Analysis of microbial community revealed that an increase in the number of VFA-producing microbial populations and the abundance of Methanobacteria resulted in the accumulation of acetic acid. This study demonstrated that co-digestion of NOR with WAS improve VFA production, thus realizing the utilization of solid wastes and reducing environmental pollution.

9.
Environ Sci Pollut Res Int ; 30(51): 111244-111255, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37814045

RESUMEN

A combined temporal and spatial research approach helps us to evaluate the ecological status of a river scientifically and comprehensively. To understand the response mechanisms of bacteria in the Li River to different environments, we conducted a 1-year study (2020-2021) and collected water samples from 18 sections of the river in October, January, April, and August. 16S sequencing was used to study the composition and structure of bacterial communities in Li River at different temporal and spatial scales. The results showed that NO3--N, TP, T, pH, and DO were significantly different on spatial and temporal scales. Alpha diversity of planktonic bacteria in Li River fluctuated significantly with the season, reaching its highest in summer. Proteobacteria remained the most dominant phylum in all seasons, but the differential microorganisms varied between seasons. Although the abundance of metabolic functions of planktonic bacteria did not show significant differences between seasons, we found that DO, TP, T, and COD were the key environmental factors affecting bacterial metabolism. In addition, the co-occurrence network analysis showed that the autumn network had a higher number of nodes and edges and exhibited a high degree of complexity, while the summer network had the highest degree of modularity and exhibited greater stability. These results deepen our knowledge of the response mechanisms of river microorganisms to temporal and spatial changes and provide a scientific reference for the study of river ecosystems.


Asunto(s)
Ecosistema , Plancton , Estaciones del Año , Ríos/química , Bacterias/genética , China , ARN Ribosómico 16S
10.
Am J Physiol Cell Physiol ; 325(5): C1252-C1266, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37694287

RESUMEN

Hydrogen sulfide (H2S) promotes microangiogenesis and revascularization after ischemia. Neovascularization starts with the destruction of intercellular junctions and is accompanied by various endothelial cell angiogenic behaviors. Follistatin-like 1 (FSTL1) is a cardiovascular-protective myokine that works against ischemic injury. The present study examined whether FSTL1 was involved in H2S-induced angiogenesis and explored the underlying molecular mechanism. We observed that H2S accelerated blood perfusion after ischemia in the mouse hindlimb ischemia model. Western blot analysis showed that H2S stabilized FSTL1 transcript and increased FSTL1 and Human antigen R (HuR) levels in skeletal muscle. RNA-interference HuR significantly inhibited the H2S-promoted increase in FSTL1 levels. Exogenous FSTL1 promoted the wound-healing migration of human umbilical vein endothelial cells (HUVECs) and increased monolayer endothelial barrier permeability. Immunostaining showed that FSTL1 increased interendothelial gap formation and decreased VE-Cadherin, Occludin, Connexin-43, and Claudin-5 expression. In addition, FSTL1 significantly increased the phosphorylation of Src and VEGFR2. However, the Src inhibitor, not the VEGFR2 inhibitor, could block FSTL1-induced effects in angiogenesis. In conclusion, we demonstrated that H2S could upregulate the expression of FSTL1 by increasing the HuR levels in skeletal muscle, and paracrine FSTL1 could initiate angiogenesis by opening intercellular junctions via the Src signaling pathway.NEW & NOTEWORTHY The myocyte-derived paracrine protein FSTL1 acts on vascular endothelial cells and initiates the process of angiogenesis by opening the intercellular junction via activating Src kinase. H2S can significantly upregulate FSTL1 protein levels in skeletal muscles by increasing HuR expression.

11.
Anal Chim Acta ; 1278: 341712, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37709455

RESUMEN

Retention and transport behaviours of microplastics (MPs) and their associated pollutants in porous media are of great concern. The homogeneity of the studied MPs in artificially controlled lab-scale studies makes rapid and accurate MP quantification feasible. In this study, an economical ethanol-diluted turbidimetry method for polypropylene (PP) and polyethylene (PE) MPs was developed. With ethanol dilution, the MP dispersion system exhibited an excellent suspension performance. Strong linear relationships were observed between MP concentrations and turbidities in both low (<1.3 mg L-1) and high (<170 mg L-1) MP concentration ranges. Solution density and MP agglomeration governed the MP suspension performance. For low surface tension and high molecular mass, the addition of ethanol decreased the contact angles of PP-MPs with solutions from 81.73 to 15.5°, and consequently improved the MP suspension performance. The suspension system was optimised to an ethanol/water (v/v) ratio of 3:2 and 4:1 for PP- and PE-MPs, when the slopes of standard curves were determined to be 1.252 and 0.471 with the recovery of 100.54 ± 3.09% and 103.19 ± 1.66%, and the limit of detection and quantification values of 0.025 and 0.082 mg L-1, and 0.060 and 0.201 mg L-1, respectively. Solution pH, salinity, and dissolved organic matter in the selected range induced acceptable fluctuations in the MP recovery and matrix effect values. The Derjaguin-Landau-Verwey-Overbeek (DLVO) energy barriers were calculated to be > 20 kT, indicating excellent tolerance to the solution matrix. Additionally, applications in real water samples were validated to demonstrate the potential of the developed method.

12.
Plants (Basel) ; 12(14)2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37514342

RESUMEN

Amendments with activators or microorganisms to enhance phytoremediation in toxic-metal-polluted soils have been widely studied. In this research, the production of indoleacetic acid, siderophore, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase by phosphate-solubilizing bacteria was investigated during a pure culture experiment. Pot experiments were performed using Cd-polluted soil with the following treatments: control (CK, only ultrapure water), orange-peel-based activator (OG), and a combination of phosphate-solubilizing bacteria (Acinetobacter pitti) and OG (APOG). Ryegrass plant height and fresh weight, Cd content in ryegrass, total and available Cd soil content, soil enzyme activity, and soil bacterial diversity were determined in this work. The findings showed that the height of ryegrass in OG and APOG increased by 14.78% and 21.23%. In the APOG group, a decreased ratio of Cd was 3.37 times that of CK, and the bioconcentration factor was 1.28 times that of CK. The neutral phosphatase activity of APOG was 1.33 times that of CK and catalase activity was 1.95 times that of CK. The activity of urease was increased by 35.48%. APOG increased the abundance of beneficial bacteria and Proteobacteria was the dominant bacterium, accounting for 57.38% in APOG. Redundancy analysis (RDA) showed that nutrient elements were conducive to the propagation of the dominant bacteria, the secretion of enzymes, and the extraction rate of Cd in the soil. The possible enhancement mechanism of phytoremediation of cadmium by A. pitti combined with OG was that, on the one hand, APOG increased soil nutrient elements and enzyme activities promoted the growth of ryegrass. On the other hand, APOG activated Cd and boosted the movement of Cd from soil to ryegrass. This research offers insight for the combination of phosphate-solubilizing bacteria with an orange-peel-based activator to improve phytoremediation of Cd-contaminated soils and also provides a new way for the resource utilization of fruit residue.

13.
Cell Rep ; 42(7): 112750, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37421623

RESUMEN

The present study examines whether there is a mechanism beyond the current concept of post-translational modifications to regulate the function of a protein. A small gas molecule, hydrogen sulfide (H2S), was found to bind at active-site copper of Cu/Zn-SOD using a series of methods including radiolabeled binding assay, X-ray absorption near-edge structure (XANES), and crystallography. Such an H2S binding enhanced the electrostatic forces to guide the negatively charged substrate superoxide radicals to the catalytic copper ion, changed the geometry and energy of the frontier molecular orbitals of the active site, and subsequently facilitated the transfer of an electron from the superoxide radical to the catalytic copper ion and the breakage of the copper-His61 bridge. The physiological relevance of such an H2S effect was also examined in both in vitro and in vivo models where the cardioprotective effects of H2S were dependent on Cu/Zn-SOD.


Asunto(s)
Cobre , Sulfuro de Hidrógeno , Cobre/metabolismo , Superóxido Dismutasa/metabolismo , Dominio Catalítico , Superóxidos , Zinc/metabolismo
14.
Sheng Li Xue Bao ; 75(3): 317-327, 2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37340641

RESUMEN

The present study aimed to investigate the protective effect of S-propargyl-cysteine (SPRC) on atherosclerosis progression in mice. A mouse model of vulnerable atherosclerotic plaque was created in ApoE-/- mice by carotid artery tandem stenosis (TS) combined with a Western diet. Macrophotography, lipid profiles, and inflammatory markers were measured to evaluate the antiatherosclerotic effects of SPRC compared to atorvastatin as a control. Histopathological analysis was performed to assess the plaque stability. To explore the protective mechanism of SPRC, human umbilical vein endothelial cells (HUVECs) were cultured in vitro and challenged with oxidized low-density lipoprotein (ox-LDL). Cell viability was determined with a Cell Counting Kit-8 (CCK-8). Endothelial nitric oxide synthase (eNOS) phosphorylation and mRNA expression were detected by Western blot and RT-qPCR respectively. The results showed that the lesion area quantified by en face photographs of the aortic arch and carotid artery was significantly less, plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) were reduced, plaque collagen content was increased and matrix metalloproteinase-9 (MMP-9) was decreased in 80 mg/kg per day SPRC-treated mice compared with model mice. These findings support the role of SPRC in plaque stabilization. In vitro studies revealed that 100 µmol/L SPRC increased the cell viability and the phosphorylation level of eNOS after ox-LDL challenge. These results suggest that SPRC delays the progression of atherosclerosis and enhances plaque stability. The protective effect may be at least partially related to the increased phosphorylation of eNOS in endothelial cells.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , Animales , Humanos , Ratones , Colesterol/metabolismo , Cisteína/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Lipoproteínas LDL/farmacología , Óxido Nítrico Sintasa de Tipo III/genética , Óxido Nítrico Sintasa de Tipo III/metabolismo , Fosforilación , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología
15.
Chembiochem ; 24(15): e202300066, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37132452

RESUMEN

The utilization of unnatural nicotinamide cofactors for reactions catalyzed by oxidoreductases has gained increasing interest. Totally synthetic nicotinamide cofactor biomimetics (NCBs) are cost-effective and convenient to synthesize. Thus, it has become increasingly important to develop enzymes that accept NCBs. Here, we have engineered SsGDH to favor a newly synthesized unnatural cofactor 3-carbamoyl-1-(4-carboxybenzyl) pyridin-1-ium (BANA+ ). Using in situ ligand minimization tool, sites 44 and 114 were identified as hotspots for mutagenesis. All the double mutants demonstrated 2.7-7.7-fold improvements in catalytic activity, and the best double mutant E44D/E114 L exhibited 10.6-fold increased catalytic efficiency toward BANA+ . These results provide valuable information for the rational engineering of oxidoreductases with versatile NCBs-dependency, as well as the design of novel biomimetic cofactors.


Asunto(s)
Biomimética , Glucosa 1-Deshidrogenasa , Glucosa 1-Deshidrogenasa/genética , Oxidorreductasas/genética , Niacinamida , Catálisis
16.
J Environ Manage ; 343: 118181, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37229857

RESUMEN

With the recent increases in energy demands, the dust hazards of coal mining caused by transportation, loading and unloading and other processes are becoming increasingly serious. To control dust in open pit coal mines more environmentally friendly and efficiently, and to promote the use and development of non-in situ high-yield urease microorganisms for dust suppression in coal mines, Bacillus pasteurii was selected for dust suppression experiments in this article. Additionally, the growth of microorganisms in the coal dust microenvironment was simulated, and the effect of microbial mineralization products on the calorific value of upper coal dust was further studied. Our findings indicated that Bacillus pasteurii induced dust suppression by forming a calcite precipitate with non-uniform particle size to coal dust cementation. Moreover, after a single spray, the wind erosion resistance efficiency was 84% when the wind speed was set at 10 m/s. The growth of microorganisms and urease activity in the coal dust leachate were largely equal to those in the control group, reaching a peak at approximately 24 h, that the maximum growth quantity of OD600 was about 1.5, and the maximum urease activity was 11 mmol·L-1·min-1. The difference between the peak heat release rate of mixed coal dust and pure coal was only 4.82 kW/m2, which would not affect the value of coal products. Non in-situ Bacillus pasteurii can be growth metabolized normally in the microenvironment of coal dust. Finally, the mechanism of coal dust suppression by mineralization of microbial bacterial solution to form calcium carbonate was described by a reaction equation, which is important for further application and development of microbial dust suppressants.


Asunto(s)
Minas de Carbón , Sporosarcina , Polvo/análisis , Ureasa , Carbonato de Calcio , Minerales , Carbón Mineral/análisis
17.
J Environ Sci (China) ; 128: 139-149, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36801030

RESUMEN

Granular activated carbon (GAC) filtration can be employed to synchronously quench residual H2O2 from the upstream UV/H2O2 process and further degrade dissolved organic matter (DOM). In this study, rapid small-scale column tests (RSSCTs) were performed to clarify the mechanisms underlying the interactions between H2O2 and DOM during the GAC-based H2O2 quenching process. It was observed that GAC can catalytically decompose H2O2, with a long-lasting high efficiency (>80% for approximately 50,000 empty-bed volumes). DOM inhibited GAC-based H2O2 quenching via a pore-blocking effect, especially at high concentrations (10 mg/L), with the adsorbed DOM molecules being oxidized by the continuously generated ·OH; this further deteriorated the H2O2 quenching efficiency. In batch experiments, H2O2 could enhance DOM adsorption by GAC; however, in RSSCTs, it deteriorated DOM removal. This observation could be attributed to the different ·OH exposure in these two systems. It was also observed that aging with H2O2 and DOM altered the morphology, specific surface area, pore volume, and the surface functional groups of GAC, owing to the oxidation effect of H2O2 and ·OH on the GAC surface as well as the effect of DOM. Additionally, the changes in the content of persistent free radicals in the GAC samples were insignificant following different aging processes. This work contributes to enhancing understanding regarding the UV/H2O2-GAC filtration scheme, and promoting the application in drinking water treatment.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico , Materia Orgánica Disuelta , Peróxido de Hidrógeno , Adsorción
18.
Curr Microbiol ; 80(2): 73, 2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36622432

RESUMEN

The presence and diversity of endophytic fungi associated with host plants are important not just for host plant growth and defense, but also impact the production of medicinal secondary metabolites. However, the correlation between endophytic fungi and crocin production in Crocus sativus (CS) remains underexplored. Here, we explore the relationship between endophytic fungal diversity and crocin content among different CS tissues and field sites. Specifically, we isolated endophytic fungi from five different field sites (Shanghai, Jiande, Huzhou, Anhui, and Hebei) and five different tissues (corm, scape, leaf, petal, and stigma) and analyzed fungal community diversity, richness, and evenness. We identified a total of 32 endophytic fungal taxa, assigned to 7 orders within 4 classes (Eurotiomycetes, Agaricomycetes, Dothideomycetes, and Sordariomycetes). The most dominant order was Eurotiales, and the most dominant genera were Penicillium and Talaromyces. Species richness tended to be highest in belowgrown tissues, such as corm and scape. Additionally, several fungal taxa were found to be either site- or tissue-specific. Three genera in particular were correlated with crocin content: Penicillium, Sistotrema, and Bjerkandera. Given the fact that endophytic microorganisms can both promote the production of secondary metabolites in host plants and potentially produce secondary metabolites themselves, further study is required to understand the mechanistic relationship between these and other fungal genera and crocin production.


Asunto(s)
Ascomicetos , Crocus , Penicillium , Hongos , Endófitos , China , Penicillium/genética
19.
Proc Natl Acad Sci U S A ; 120(3): e2205315120, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36623195

RESUMEN

Human land-use results in widespread range change across taxa. Anthropogenic pressures can result in species' realized niches expanding, shifting, or contracting. Marginalization occurs when contraction constrains species to the geographic or ecological extremes of their historic niche. Using 4,785 terrestrial mammal species, we show that range contraction results in niche space and habitat diversity loss. Additionally, ecological marginalization is a common consequence of range contraction caused by human land use change. Remnant populations become located in the climatic and topographic extremes of their historic niche that are more likely to be at the periphery of their historic niche at greater distances from historic niche centroids. This ecological marginalization is associated with poor performance and increased extinction risk independent of geographic range loss. Range loss and marginalization may create a "double whammy" in vulnerable groups, such as large-bodied species and species with small geographical range size. Our results reveal a hitherto unrecognized conservation threat that is vital to incorporate into conservation assessment and management.


Asunto(s)
Ecosistema , Mamíferos , Animales , Humanos , Geografía , Extinción Biológica
20.
Respir Res ; 23(1): 372, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36550474

RESUMEN

PURPOSE: To investigate the prognostic value of quantitative analysis of CT among patients with idiopathic pulmonary fibrosis (IPF) by quantifying the fibrosis extent and to attempt to provide precise medium-long term prognostic predictions for individual patients. METHODS: This was a retrospective cohort study that included 95 IPF patients in Zhongshan Hospital, Fudan University. 64 patients firstly diagnosed with IPF from 2009 to 2015 was included as the derivation cohort. Information regarding sex, age, the Gender-Age-Physiology (GAP) index, high-resolution computed tomography (HRCT) images, survival status, and pulmonary function parameters including forced vital capacity (FVC), FVC percent predicted (FVC%pred), diffusing capacity of carbon monoxide (DLCO), DLCO percent predicted (DLCO%pred), carbon monoxide transfer coefficient (KCO), KCO percent predicted (KCO%pred) were collected. 31 patients were included in the validation cohort. The Synapse 3D software was used to quantify the fibrotic lung volume (FLV) and total lung volume (TLV). The ratio of FLV to TLV was calculated and labeled CTFLV/TLV%, reflecting the extent of fibrosis. All the physiological variants and CTFLV/TLV% were analyzed for the dimension of survival through both univariate analysis and multivariate analysis. Formulas for predicting the probability of death based on the baseline CTFLV/TLV% were calculated by logistic regression, and validated by the validation cohort. RESULTS: The univariate analysis indicated that CTFLV/TLV% along with DLCO%pred, KCO%pred and GAP index were significantly correlated with survival. However, only CTFLV/TLV% was meaningful in the multivariate analysis for prognostic prediction (HR 1.114, 95% CI 1.047-1.184, P = 0.0006), and the best cutoff was 11%, based on receiver operating characteristic (ROC) curve analysis. The survival times for the CTFLV/TLV% ≤ 11% and CTFLV/TLV% > 11% groups were significantly different. Given the CTFLV/TLV% data, the death probability of a patient at 1 year, 3 years and 5 years could be calculated by using a particular formula. The formulas were tested by the validation cohort, showed high sensitivity (88.2%), specificity (92.8%) and accuracy (90.3%). CONCLUSION: Quantitative volume analysis of CT might be useful for evaluating the extent of fibrosis in the lung. The CTFLV/TLV% could be a valuable biomarker for precisely predicting the medium-long term prognosis of individual patients with IPF.


Asunto(s)
Monóxido de Carbono , Fibrosis Pulmonar Idiopática , Humanos , Estudios Retrospectivos , Fibrosis Pulmonar Idiopática/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Capacidad Vital , Pronóstico , Fibrosis
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