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1.
Angew Chem Int Ed Engl ; : e202416947, 2024 Sep 29.
Article in English | MEDLINE | ID: mdl-39343739

ABSTRACT

Lithium-carbon dioxide (Li-CO2) and Li-air batteries hold great potential in achieving carbon neutral given their ultrahigh theoretical energy density and eco-friendly features. However, these Li-gas batteries still suffer from low discharging-charging rate and poor cycling life due to sluggish decomposition kinetics of discharge products especially Li2CO3. Here we report the theory-guided design and preparation of unconventional phase metal heteronanostructures as cathode catalysts for high-performance Li-CO2/air batteries. The assembled Li-CO2 cells with unconventional phase 4H/face-centered cubic (fcc) ruthenium-nickel heteronanostructures deliver a narrow discharge-charge gap of 0.65 V, excellent rate capability and long-term cycling stability over 200 cycles at 250 mA g-1. The constructed Li-air batteries can steadily run for above 150 cycles in ambient air. Electrochemical mechanism studies reveal that 4H/fcc Ru-Ni with high-electroactivity facets can boost redox reaction kinetics and tune discharge reactions towards Li2C2O4 path, alleviating electrolyte/catalyst failures induced by the aggressive singlet oxygen from solo decomposition of Li2CO3.

2.
Sheng Wu Gong Cheng Xue Bao ; 40(9): 3282-3295, 2024 Sep 25.
Article in Chinese | MEDLINE | ID: mdl-39319740

ABSTRACT

In recent years, artificial intelligence has been employed to empower synthetic biology, demonstrating great potential in the simulation and prediction of protein structures as well as the design and optimization of regulatory elements and metabolic networks. Integrating artificial intelligence into the teaching of Synthetic Biology is in line with the development trends of synthetic biology and can promote the cultivation of interdisciplinary high-level talents and collaborative innovation. This paper expounds the idea of integrating artificial intelligence into the teaching of Synthetic Biology from establishing interdisciplinary course contents and teaching methods, simultaneously considering the fundamentals and application of artificial intelligence in synthetic biology, cultivating independent learning and innovative practice abilities, and enhancing the ethics education related to artificial intelligence. Furthermore, a system integrating artificial intelligence with the teaching contents of Synthetic Biology is designed, which focuses on supplementing fundamentals of artificial intelligence and incorporating artificial intelligence into the classroom and experimental teaching contents of Synthetic Biology. Moreover, with the course of Synthetic Biology in Jiangnan University as an example, this paper presents the pathway of integrating artificial intelligence into the teaching of this course under the background of discipline crossing. Finally, the teaching effects are expected.


Subject(s)
Artificial Intelligence , Synthetic Biology , Synthetic Biology/education , Teaching
3.
Bioresour Technol ; 413: 131493, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39284374

ABSTRACT

The 5-hydroxyectoine is a natural protective agent with long-lasting moisturising and radiation resistance properties. It can be naturally synthesized by some extremophiles using the "bacterial milking" process, but this can corrode bioreactors and downstream purification may cause environmental pollution. In this study, an engineered Escherichia coli (E. coli) strain was constructed for the 5-hydroxyectoine production. First, three ectoine hydroxylases were characterised and the enzyme from Halomonas elongata was the most effective. The L-2,4-diaminobutyrate transaminase mutant was introduced into the engineered strain, which could accumulate 2.8 g/L 5-hydroxyectoine in shake flasks. By activating the glyoxylate cycle and balancing the α-ketoglutarate distribution, the 5-hydroxyectoine titer was further increased to 3.4 g/L. Finally, the optimized strain synthesized 58 g/L 5-hydroxyectoine via a semi-continuous feeding process in a NaCl-free medium. Overall, this study reported the highest titer of 5-hydroxyectoine synthesized by E. coli and established a low-salt fermentation process through the aforementioned efforts.

4.
Adv Mater ; : e2407889, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39240011

ABSTRACT

Electrochemical nitrate reduction reaction (NO3RR) is emerging as a promising strategy for nitrate removal and ammonia (NH3) production using renewable electricity. Although great progresses have been achieved, the crystal phase effect of electrocatalysts on NO3RR remains rarely explored. Here, the epitaxial growth of unconventional 2H Cu on hexagonal close-packed (hcp) IrNi template, resulting in the formation of three IrNiCu@Cu nanostructures, is reported. IrNiCu@Cu-20 shows superior catalytic performance, with NH3 Faradaic efficiency (FE) of 86% at -0.1 (vs reversible hydrogen electrode [RHE]) and NH3 yield rate of 687.3 mmol gCu -1 h-1, far better than common face-centered cubic Cu. In sharp contrast, IrNiCu@Cu-30 and IrNiCu@Cu-50 covered by hcp Cu shell display high selectivity toward nitrite (NO2 -), with NO2 - FE above 60% at 0.1 (vs RHE). Theoretical calculations have demonstrated that the IrNiCu@Cu-20 has the optimal electronic structures for NO3RR due to the highest d-band center and strongest reaction trend with the lowest energy barriers. The high electroactivity of IrNiCu@Cu-20 originates from the abundant low coordination of Cu sites on the surface, which guarantees the fast electron transfer to accelerate the intermediate conversions. This work provides a feasible tactic to regulate the product distribution of NO3RR by crystal phase engineering of electrocatalysts.

5.
Bioresour Technol ; 412: 131403, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39222859

ABSTRACT

The cyclohexane organic acid 3-dehydroshikimate (DHS) has potent antioxidant activity and is widely utilised in chemical and pharmaceutical industries. However, its production requires a long fermentation with a suboptimal yield and low productivity, and a disproportionate growth-to-production ratio impedes the upscaling of DHS synthesis in microbial cell factories. To overcome these limitations, competing and degradation pathways were knocked-out and key enzymes were balanced in an engineered Escherichia coli production strain, resulting in 12.2 g/L DHS. Furthermore, to achieve equilibrium between cell growth and DHS production, a CRISPRi-based temperature-responsive multi-component repressor system was developed to dynamically control the expression of critical genes (pykF and aroE), resulting in a 30-fold increase in DHS titer. After 33 h fermentation in 5 L bioreactor, the DHS titer, productivity and yield reached 94.2 g/L, 2.8 g/L/h and 55 % glucose conversion, respectively. The results provided valuable insight into the production of DHS and its derivatives.


Subject(s)
Escherichia coli , Fermentation , Metabolic Engineering , Shikimic Acid , Temperature , Escherichia coli/metabolism , Shikimic Acid/metabolism , Metabolic Engineering/methods , Metabolic Networks and Pathways , Bioreactors , Glucose/metabolism
6.
Sheng Wu Gong Cheng Xue Bao ; 40(9): 3011-3024, 2024 Sep 25.
Article in Chinese | MEDLINE | ID: mdl-39319721

ABSTRACT

Neohesperidin is a flavonoid glycoside widely used in the food and pharmaceutical industries. The current production of neohesperidin mainly relies on extraction from plants. Microbial fermentation demonstrates a promising prospect as an environmentally friendly, efficient, and economical method. In this study, we designed and constructed the biosynthetic pathway of neohesperidin in an Escherichia coli strain by introducing the glycosyltransferase UGT73B2 from Arabidopsis thaliana, rhamnose synthase VvRHM-NRS from Vitis vinifera, and rhamnose transferase Cm1,2RhaT from Citrus maxima. After optimization of the module and the uridine diphosphate (UDP)-glucose synthetic pathway, the engineered strain produced 4.64 g/L neohesperidin in a 5 L bioreactor, and the molar conversion rate of hesperetin was 45.8%. This has been the highest titer reported to date for the biosynthesis of neohesperidin in microorganisms. This study lays a foundation for the construction and application of strains with high yields of neohesperidin and provides a potential choice for the microbial production of other flavonoid glycosides.


Subject(s)
Escherichia coli , Hesperidin , Metabolic Engineering , Hesperidin/metabolism , Hesperidin/biosynthesis , Hesperidin/analogs & derivatives , Escherichia coli/genetics , Escherichia coli/metabolism , Glycosyltransferases/genetics , Glycosyltransferases/metabolism , Arabidopsis/genetics , Citrus , Fermentation , Biosynthetic Pathways/genetics , Vitis
7.
J Agric Food Chem ; 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39269285

ABSTRACT

Methane, a byproduct of agricultural activities, has shown potential as a nonedible substrate for biomanufacturing. The production of succinate by a methanotrophic bacterium utilizing methane presents an innovative route for the sustainable synthesis of chemicals. In this study, Methylotuvimicrobium buryatense 5GB1S was genetically modified through the reconstruction of an artificial serine cycle to enable the bioconversion of both methane and CO2 into succinate. The 13C labeling analysis confirmed the CO2 fixing in M. buryatense 5GB1S, leading to a 46% improvement in carbon conversion efficiency and a 107% increase in succinate production compared to the wild-type strain. The transcriptome data on carbon metabolisms was assessed to guide future optimizations for strengthening the overall carbon flux from methane to succinate. Finally, the maximum succinate titer of 299.36 mg/L was achieved under oxygen-limited conditions in 3 L bioreactors, which resulted in the volumetric productivity of 199.60 mg/L/day, representing a 23-fold enhancement compared to the wild-type strain. This study offers a new strategy for upcycling greenhouse gases into succinate in a sustainable manner through methanotrophic-based biomanufacturing.

8.
Adv Sci (Weinh) ; : e2407712, 2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39206778

ABSTRACT

Pulmonary arterial hypertension (PAH) is associated with aberrant pulmonary vascular smooth muscle cell (PASMC) function and vascular remodeling. MiR-30d plays an important role in the pathogenesis of several cardiovascular disorders. However, the function of miR-30d in PAH progression remained unknown. Our study shows that circulating miR-30d level is significantly reduced in the plasma from PAH patients. In miR-30d transgenic (TG) rats, overexpressing miR-30d attenuates monocrotaline (MCT)-induced pulmonary hypertension (PH) and pulmonary vascular remodeling. Increasing miR-30d also inhibits platelet-derived growth factor-bb (PDGF-bb)-induced proliferation and migration of human PASMC. Metadherin (MTDH) and phosphodiesterase 5A (PDE5A) are identified as direct target genes of miR-30d. Meanwhile, nuclear respiratory factor 1 (NRF1) acts as a positive upstream regulator of miR-30d. Using miR-30d knockout (KO) rats treated with sildenafil, a PDE5A inhibitor that is used in clinical PAH therapies, it is further found that suppressing miR-30d partially attenuates the beneficial effect of sildenafil against MCT-induced PH and vascular remodeling. The present study shows a protective effect of miR-30d against PAH and pulmonary vascular remodeling through targeting MTDH and PDE5A and reveals that miR-30d modulates the beneficial effect of sildenafil in treating PAH. MiR-30d should be a prospective target to treat PAH and pulmonary vascular remodeling.

9.
J Agric Food Chem ; 72(35): 19436-19446, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39180741

ABSTRACT

Dihydroquercetin is a vital flavonoid compound with a wide range of physiological activities. However, factors, such as metabolic regulation, limit the heterologous synthesis of dihydroquercetin in microorganisms. In this study, flavanone 3-hydroxylase (F3H) and flavanone 3'-hydroxylase (F3'H) were screened from different plants, and their co-expression in Saccharomyces cerevisiae was optimized. Promoter engineering and redox partner engineering were used to optimize the corresponding expression of genes involved in the dihydroquercetin synthesis pathway. Dihydroquercetin production was further improved through multicopy integration pathway genes and systems metabolic engineering. By increasing NADPH and α-ketoglutarate supply, the catalytic efficiency of F3'H and F3H was improved, thereby effectively increasing dihydroquercetin production (235.1 mg/L). Finally, 873.1 mg/L dihydroquercetin titer was obtained by fed-batch fermentation in a 5-L bioreactor, which is the highest dihydroquercetin production achieved through de novo microbial synthesis. These results established a pivotal groundwork for flavonoids synthesis.


Subject(s)
Metabolic Engineering , Quercetin , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics , Quercetin/analogs & derivatives , Quercetin/metabolism , Quercetin/biosynthesis , Fermentation , Mixed Function Oxygenases/genetics , Mixed Function Oxygenases/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Biosynthetic Pathways
10.
Int J Mol Sci ; 25(16)2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39201766

ABSTRACT

Sulfate transporters (SULTRs) are essential for the transport and absorption of sulfate in plants and serve as critical transport proteins within the sulfur metabolism pathway, significantly influencing plant growth, development, and stress adaptation. A bioinformatics analysis of SULTR genes in soybean was performed, resulting in the identification and classification of twenty-eight putative GmSULTRs into four distinct groups. In this study, the characteristics of the 28 GmSULTR genes, including those involved in collinearity, gene structure, protein motifs, cis-elements, tissue expression patterns, and the response to abiotic stress and plant hormone treatments, were systematically analyzed. This study focused on conducting a preliminary functional analysis of the GmSULTR3;1a gene, wherein a high expression level of GmSULTR3;1a in the roots, stems, and leaves was induced by a sulfur deficiency and GmSULTR3;1a improved the salt tolerance. A further functional characterization revealed that GmSULTR3;1a-overexpressing soybean hairy roots had higher SO42-, GSH, and methionine (Met) contents compared with the wild-type (WT) plant. These results demonstrate that the overexpression of GmSULTR3;1a may promote the sulfur assimilation metabolism and increase the content of sulfur-containing amino acids in plants.


Subject(s)
Gene Expression Regulation, Plant , Glycine max , Plant Proteins , Stress, Physiological , Sulfate Transporters , Glycine max/genetics , Glycine max/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Stress, Physiological/genetics , Sulfate Transporters/genetics , Sulfate Transporters/metabolism , Multigene Family , Phylogeny , Sulfur/metabolism , Plant Roots/metabolism , Plant Roots/genetics , Salt Tolerance/genetics , Sulfates/metabolism , Plants, Genetically Modified/genetics , Gene Expression Profiling
11.
Bioresour Technol ; 411: 131189, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39127360

ABSTRACT

Vanillin is an important flavouring agent applied in food, spices, pharmaceutical industries and other fields. Microbial biosynthesis of vanillin is considered a sustainable and economically feasible alternative to traditional chemical synthesis. In this study, Escherichia coli K12 MG1655 was used for the de novo synthesis of VAN by screening highly active carboxylic acid reductases and catechol O-methyltransferases, optimising the protocatechuic acid pathway, and regulating competitive metabolic pathways. Additionally, major alcohol by-products were identified and decreased by deleting three endogenous aldo-keto reductases and three alcohol dehydrogenases. Finally, a highest VAN titer was achieved to 481.2 mg/L in a 5 L fermenter from glucose. This work provides a valuable example of pathway engineering and screens several enzyme variants for the first time in E. coli.


Subject(s)
Benzaldehydes , Escherichia coli K12 , Metabolic Engineering , Benzaldehydes/metabolism , Metabolic Engineering/methods , Escherichia coli K12/metabolism , Escherichia coli K12/genetics , Fermentation
12.
ACS Synth Biol ; 13(8): 2567-2576, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39092670

ABSTRACT

Collagen II (COL2) is the major component of cartilage tissue and is widely applied in pharmaceuticals, food, and cosmetics. In this study, COL fragments were extracted from human COL2 for secretory expression in Pichia pastoris. Three variants were successfully secreted by shake flask cultivation with a yield of 73.3-100.7 mg/L. The three COL2 variants were shown to self-assemble into triple-helix at 4 °C and capable of forming higher order assembly of nanofiber and hydrogel. The bioactivities of the COL2 variants were validated, showing that sample 205 exhibited the best performance for inducing fibroblast differentiation and cell migration. Meanwhile, sample 205 and 209 exhibited higher capacity for inducing in vitro blood clotting than commercial mouse COL1. To overexpress sample 205, the expression cassettes were constructed with different promoters and signal peptides, and the fermentation condition was optimized, obtaining a yield of 172 mg/L for sample 205. Fed-batch fermentation was carried out using a 5 L bioreactor, and the secretory protease Pep4 was knocked out to avoid sample degradation, finally obtaining a yield of 3.04 g/L. Here, a bioactive COL2 fragment was successfully identified and can be overexpressed in P. pastoris; the variant may become a potential biomaterial for skin care.


Subject(s)
Collagen Type II , Humans , Collagen Type II/genetics , Collagen Type II/metabolism , Mice , Animals , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Recombinant Proteins/biosynthesis , Fermentation , Pichia/genetics , Pichia/metabolism , Cell Movement/genetics , Fibroblasts/metabolism , Cell Differentiation , Bioreactors , Saccharomycetales/genetics , Saccharomycetales/metabolism , Nanofibers/chemistry
13.
Appl Microbiol Biotechnol ; 108(1): 432, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39102054

ABSTRACT

Infections caused by Staphylococcus aureus pose a significant global public problem. Therefore, new antibiotics and therapeutic strategies are needed to combat this pathogen. This investigation delves into the effects of iclaprim, a newly discovered inhibitor of folic acid synthesis, on S. aureus virulence. The phenotypic and genotypic effects of iclaprim were thoroughly examined in relation to virulence factors, biofilm formation, and dispersal, as well as partial virulence-encoding genes associated with exoproteins, adherence, and regulation in S. aureus MW2, N315, and ATCC 25923. Then, the in vivo effectiveness of iclaprim on S. aureus pathogenicity was explored by a Galleria mellonella larvae infection model. The use of iclaprim at sub-inhibitory concentrations (sub-MICs) resulted in a reduction of α-hemolysin (Hla) production and a differential effect on the activity of coagulase in S. aureus strains. The results of biofilm formation and eradication assay showed that iclaprim was highly effective in depolymerizing the mature biofilm of S. aureus strains at concentrations of 1 MIC or greater, however, inhibited the biofilm-forming ability of only strains N315 and ATCC 25923 at sub-MICs. Interestingly, treatment of strains with sub-MICs of iclaprim resulted in significant stimulation or suppression of most virulence-encoding genes expression. Iclaprim did not affect the production of δ-hemolysin or staphylococcal protein A (SpA), nor did it impact the total activity of proteases, nucleases, and lipases. In vivo testing showed that sub-MICs of iclaprim significantly improves infected larvae survival. The present study offered valuable insights towards a better understating of the influence of iclaprim on different strains of S. aureus. The findings suggest that iclaprim may have potential as an anti-virulence and antibiofilm agent, thus potentially mitigating the pathogenicity of S. aureus and improving clinical outcomes associated with infections caused by this pathogen. KEY POINTS: • Iclaprim effectively inhibits α-hemolysin production and biofilm formation in a strain-dependent manner and was an excellent depolymerizing agent of mature biofilm • Iclaprim affected the mRNA expression of virulence-encoding genes associated with exoproteins, adherence, and regulation • In vivo study in G. mellonella larvae challenged with S. aureus exhibited that iclaprim improves larvae survival.


Subject(s)
Anti-Bacterial Agents , Biofilms , Larva , Microbial Sensitivity Tests , Staphylococcal Infections , Staphylococcus aureus , Virulence Factors , Staphylococcus aureus/drug effects , Staphylococcus aureus/pathogenicity , Staphylococcus aureus/genetics , Biofilms/drug effects , Animals , Virulence Factors/genetics , Anti-Bacterial Agents/pharmacology , Virulence/drug effects , Staphylococcal Infections/microbiology , Staphylococcal Infections/drug therapy , Larva/microbiology , Moths/microbiology , Hemolysin Proteins/genetics , Folic Acid/pharmacology , Folic Acid/biosynthesis , Folic Acid Antagonists/pharmacology , Coagulase/metabolism , Disease Models, Animal , Pyrimidines
14.
Brief Bioinform ; 25(5)2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39101501

ABSTRACT

Engineering enzyme-substrate binding pockets is the most efficient approach for modifying catalytic activity, but is limited if the substrate binding sites are indistinct. Here, we developed a 3D convolutional neural network for predicting protein-ligand binding sites. The network was integrated by DenseNet, UNet, and self-attention for extracting features and recovering sample size. We attempted to enlarge the dataset by data augmentation, and the model achieved success rates of 48.4%, 35.5%, and 43.6% at a precision of ≥50% and 52%, 47.6%, and 58.1%. The distance of predicted and real center is ≤4 Å, which is based on SC6K, COACH420, and BU48 validation datasets. The substrate binding sites of Klebsiella variicola acid phosphatase (KvAP) and Bacillus anthracis proline 4-hydroxylase (BaP4H) were predicted using DUnet, showing high competitive performance of 53.8% and 56% of the predicted binding sites that critically affected the catalysis of KvAP and BaP4H. Virtual saturation mutagenesis was applied based on the predicted binding sites of KvAP, and the top-ranked 10 single mutations contributed to stronger enzyme-substrate binding varied while the predicted sites were different. The advantage of DUnet for predicting key residues responsible for enzyme activity further promoted the success rate of virtual mutagenesis. This study highlighted the significance of correctly predicting key binding sites for enzyme engineering.


Subject(s)
Machine Learning , Binding Sites , Protein Engineering/methods , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Acid Phosphatase/chemistry , Acid Phosphatase/genetics , Acid Phosphatase/metabolism , Substrate Specificity , Bacillus anthracis/genetics , Bacillus anthracis/enzymology , Klebsiella/genetics , Klebsiella/enzymology , Ligands , Protein Binding , Models, Molecular , Neural Networks, Computer
15.
J Ethnopharmacol ; 335: 118626, 2024 Dec 05.
Article in English | MEDLINE | ID: mdl-39053716

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Banxia Xiexin Decoction (BXD) is one of the seven classic prescriptions of the special decoction method (SDM) of "removing dregs and decocting again", which has been widely used in inflammatory bowel diseases such as ulcerative colitis (UC). However, the impacts of SDM have not been fully investigated, either on the components or on the biological effects. AIM OF THE STUDY: This study aimed to investigate the rational of SDM traditionally recorded about BXD, re-decoction after dreg-removal, by comparing with the contemporary general decoction method (GDM) from the perspective of phase states, in the bioactive components from the perspective of phase states, and their corresponding pharmacodynamic effects on a particular UC rat model. METHODS: The BXD decoctions were respectively obtained by SDM and GDM, together with the different samples with different decocting time. The phase state samples (true solution, colloidal phase, and precipitated phase), were also obtained after a series of separation process and characterized. The multi-components in the in-process decoctions, original decoctions and phase state samples were quantitatively determined. HPLC fingerprint spectrum of the samples were also detected and compared with chemometrics analysis. A rat model of ulcerative colitis with cold-heat complex syndrome was established, on which the pharmacodynamic effects of different phases of SDM-made BXD were investigated. RESULTS: The results showed that the contents of eight marker components in SDM-made decoction were significantly higher than those in GDM-made decoction. Compared with the precipitated phases and true solutions, the colloidal phase was confirmed to obtain absolutely higher contents of the components (except berberine). The analysis on HPLC fingerprints also revealed that the profiles of colloidal phase showed the majority of the characteristics of original decoctions, when compared with the other phases. The results showed the BXD group, precipitated phase group and colloidal phase group had certain therapeutic effects on the ulcerative colitis rats with cold-heat complex syndrome, among which the original decoction group showed optimal effects, followed by the colloidal phase. CONCLUSION: The study has provided the experimental evidence of the bioactive components and pharmacodynamic effects on the rational of SDM, as originally recorded about the classic prescription, which might provide useful idea for the interpretation on medicinal properties of TCM compound prescriptions, and contemporary TCM innovative drug developments.


Subject(s)
Colitis, Ulcerative , Drugs, Chinese Herbal , Rats, Sprague-Dawley , Animals , Colitis, Ulcerative/drug therapy , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/chemistry , Male , Rats , Disease Models, Animal , Colon/drug effects , Colon/metabolism , Colon/pathology , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry
16.
Neurochem Res ; 49(10): 2871-2887, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39026086

ABSTRACT

Brain injury caused by stroke has a high rate of mortality and remains a major medical challenge worldwide. In recent years, there has been significant attention given to the use of human Umbilical cord-derived Mesenchymal Stem Cells (hUC-MSCs) for the treatment of stroke in different adult and neonate animal models of stroke. However, using hUC-MSCs by systemic administration to treat ischemic stroke has not been investigated sufficiently. In this study, we conducted various experiments to explore the neuroprotection of hUC-MSCs in rats. Our findings demonstrate that an intravenous injection of a high dose of hUC-MSCs at 2 × 10^7 cells/kg markedly ameliorated brain injury resulting from ischemic stroke. This improvement was observed one day after inducing transient middle cerebral artery occlusion (MCAO) and subsequent reperfusion in rats. Notably, the efficacy of this single administration of hUC-MSCs surpassed that of edaravone, even when the latter was used continuously over three days. Mechanistically, secretory factors derived from hUC-MSCs, such as HGF, BDNF, and TNFR1, ameliorated the levels of MDA and T-SOD to regulate oxidative stress. In particular, TNFR1 also improved the expression of NQO-1 and HO-1, important proteins associated with oxidative stress. More importantly, TNFR1 played a significant role in reducing inflammation by modulating IL-6 levels in the blood. Furthermore, TNFR1 was observed to influence the permeability of the blood-brain barrier (BBB) as demonstrated in the evan's blue experiment and protein expression of ZO-1. This study represented a breakthrough in traditional methods and provided a novel strategy for clinical medication and trials.


Subject(s)
Ischemic Stroke , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Oxidative Stress , Rats, Sprague-Dawley , Umbilical Cord , Animals , Oxidative Stress/physiology , Humans , Mesenchymal Stem Cell Transplantation/methods , Mesenchymal Stem Cells/metabolism , Umbilical Cord/cytology , Male , Ischemic Stroke/metabolism , Ischemic Stroke/therapy , Rats , Inflammation/metabolism , Brain Injuries/metabolism , Brain Injuries/therapy , Neuroprotection/physiology , Infarction, Middle Cerebral Artery/therapy , Infarction, Middle Cerebral Artery/metabolism
17.
Synth Syst Biotechnol ; 9(4): 784-792, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39021361

ABSTRACT

The diterpene ent-copalol is an important precursor to the synthesis of andrographolide and is found only in green chiretta (Andrographis paniculata). De novo biosynthesis of ent-copalol has not been reported, because the catalytic activity of ent-copalyl diphosphate synthase (CPS) is very low in microorganisms. In order to achieve the biosynthesis of ent-copalol, Saccharomyces cerevisiae was selected as the chassis strain, because its endogenous mevalonate pathway and dephosphorylases could provide natural promotion for the synthesis of ent-copalol. The strain capable of synthesizing diterpene geranylgeranyl pyrophosphate was constructed by strengthening the mevalonate pathway genes and weakening the competing pathway. Five full-length ApCPSs were screened by transcriptome sequencing of A. paniculata and ApCPS2 had the best activity and produced ent-CPP exclusively. The peak area of ent-copalol was increased after the ApCPS2 saturation mutation and its configuration was determined by NMR and ESI-MS detection. By appropriately optimizing acetyl-CoA supply and fusion-expressing key enzymes, 35.6 mg/L ent-copalol was generated. In this study, de novo biosynthesis and identification of ent-copalol were achieved and the highest titer ever reported. It provides a platform strain for the further pathway analysis of andrographolide and derivatives and provides a reference for the synthesis of other pharmaceutical intermediates.

18.
Noncoding RNA Res ; 9(4): 1040-1049, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39022686

ABSTRACT

Thoracic aortic dissection (TAD) is a life-threatening vascular disease manifested as intramural bleeding in the medial layers of the thoracic aorta. The key histopathologic feature of TAD is medial degeneration, characterized by depletion of vascular smooth muscle cells (VSMCs) and degradation of extracellular matrix (ECM). MicroRNA, as essential epigenetic regulators, can inhibit the protein expression of target genes without modifying the sequences. This study aimed to elucidate the role and underlying mechanism of miR-20a, a member of the miR-17-92 cluster, in regulating ECM degradation during the pathogenesis of TAD. The expression of the miR-17-92 cluster was significantly increased in synthetic VSMCs derived from TAD lesions compared to contractile VSMCs isolated from normal thoracic aortas. Notably, the expression of miR-20a was increased in VSMCs in response to serum exposure and various stimuli. In TAD lesions, the expression of miR-20a was significantly negatively correlated with that of elastin. Elevated expression of miR-20a was also observed in thoracic aortas of TAD mice induced by ß-aminopropionitrile fumarate and angiotensin II. Overexpression of miR-20a via mimic transfection enhanced the growth and invasive capabilities of VSMCs, with no significant impact on their migratory activity or the expression of phenotypic markers (α-SMA, SM22, and OPN). Silencing of miR-20a with inhibitor transfection mitigated the hyperactivation of MMP2 in VSMCs stimulated by PDGF-bb, as evidenced by reduced levels of active-MMP2 and increased levels of pro-MMP2. Subsequently, TIMP2 was identified as a novel target gene of miR-20a. The role of miR-20a in promoting the activation of MMP2 was mediated by the suppression of TIMP2 expression in VSMCs. In addition, the elevated expression of miR-20a was found to be directly driven by Nanog in VSMCs. Collectively, these findings indicate that miR-20a plays a crucial role in maintaining the homeostasis of the thoracic aortic wall during TAD pathogenesis and may represent a potential therapeutic target for TAD.

19.
Heliyon ; 10(13): e33558, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39071571

ABSTRACT

Herlyn-Werner-Wunderlich syndrome (HWWS) is a rare congenital genitourinary abnormality defined by uterine didelphys, obstructed hemivagina, and ipsilateral urological anomalies. Accurate diagnosis and prompt commencement of therapy can be difficult owing to heterogeneous genitourinary malformation among different patients. This is a case report of a patient with rare HWWS with uterine didelphys, obstructed hemivagina, vagina-ureteral remnant fistula (Gartner's duct cyst), and ipsilateral kidney dysgenesis who complained of intermittent abdominal pain during menstruation. The right ureteral remnant of the patient was distinctive, with three portions. The upper section was connected to the right dysplastic kidney, the lower section formed the fistulous tract with the vagina and bladder, while the middle section communicated with Gartner's Duct Cyst, which merged with the vagina and opened to the posterior cavity of hemivagina. The lower section of the right ureter was excised and ligated during laparoscopic surgery, while the upper section was excised. The patient recovered after surgery. We presented this rare case and conducted a literature review to provide a more comprehensive understanding of HWWS. This could help gynecologists effectively reduce misdiagnosis and missed diagnosis, especially when combined with complicated urinary malformation.

20.
Bioresour Technol ; 406: 131098, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38986886

ABSTRACT

As the highest-demand vitamin, the development of a one-step vitamin C synthesis process has been slow for a long time. In previous research, a Gluconobacter oxydans strain (GKLG9) was constructed that can directly synthesize 2-keto-L-gulonic acid (2-KLG) from glucose, but carbon source utilization remained low. Therefore, this study first identified the gene 4kas (4-keto-D-arabate synthase) to reduce the loss of extracellular carbon and inhibit the browning of fermentation broth. Then, promoter engineering was conducted to enhance the intracellular glucose transport pathway and concentrate intracellular glucose metabolism on the pentose phosphate pathway to provide more reducing power. Finally, by introducing the D-sorbitol pathway, the titer of 2-KLG was increased to 38.6 g/L within 60 h in a 5-L bioreactor, with a glucose-to-2-KLG conversion rate of about 46 %. This study is an important step in the development of single-bacterial one-step fermentation to produce 2-KLG.


Subject(s)
Gluconobacter oxydans , Glucose , Sorbitol , Gluconobacter oxydans/metabolism , Gluconobacter oxydans/genetics , Glucose/metabolism , Sorbitol/metabolism , Fermentation , Metabolic Engineering/methods , Bioreactors , Promoter Regions, Genetic , Sugar Acids/metabolism , Genetic Engineering
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