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1.
Synth Syst Biotechnol ; 9(3): 577-585, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38708056

RESUMO

Strengthening the expression level of integrated genes on the genome is crucial for consistently expressing key enzymes in microbial cell factories for efficient bioproduction in synthetic biology. In comparison to plasmid-based multi-copy expression, the utilization of chromosomal multi-copy genes offers increased stability of expression level, diminishes the metabolic burden on host cells, and enhances overall genetic stability. In this study, we developed the "BacAmp", a stabilized gene integration expression and copy number amplification system for high-level expression in Bacillus subtilis, which was achieved by employing a combination of repressor and non-natural amino acids (ncAA)-dependent expression system to create a reversible switch to control the key gene recA for homologous recombination. When the reversible switch is turned on, genome editing and gene amplification can be achieved. Subsequently, the reversible switch was turned off therefore stabilizing the gene copy number. The stabilized gene amplification system marked by green fluorescent protein, achieved a 3-fold increase in gene expression by gene amplification and maintained the average gene copy number at 10 after 110 generations. When we implemented the gene amplification system for the regulation of N-acetylneuraminic acid (NeuAc) synthesis, the copy number of the critical gene increased to an average of 7.7, which yielded a 1.3-fold NeuAc titer. Our research provides a new avenue for gene expression in synthetic biology and can be applied in metabolic engineering in B. subtilis.

2.
Environ Pollut ; 351: 124084, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38697245

RESUMO

Due to the potential impacts of microplastics (MPs) and nanoplastics (NPs) on algal growth and thereby affect the climate-relevant substances, dimethylsulfoniopropionate (DMSP) and dimethyl sulfide (DMS), we studied the polystyrene (PS) MPs and NPs of 1 µm and 80 nm impacts on the growth, chlorophyll content, reactive oxygen species (ROS), antioxidant enzyme activity, and DMS/DMSP production in Emiliania huxleyi. E. huxleyi is a prominent oceanic alga that plays a key role in DMS and DMSP production. The results revealed that high concentrations of MPs and NPs inhibited the growth, carotenoid (Car), and Chl a concentrations of E. huxleyi. However, short-time exposure to low concentrations of PS MPs and NPs stimulated the growth of E. huxleyi. Furthermore, high concentrations of MPs and NPs resulted in an increase in the superoxide anion radical (O2.-) production rate and a decrease in the malondialdehyde (MDA) content compared with the low concentrations. Exposure to MPs and NPs at 5 mg L-1 induced superoxide dismutase (SOD) activity as a response to scavenging ROS. High concentrations of MPs and NPs significantly inhibited the production of DMSP and DMS. The findings of this study support the potential ecotoxicological impacts of MPs and NPs on algal growth, antioxidant system, and dimethylated sulfur compounds production, which maybe potentially impact the global climate.

3.
Int J Biol Macromol ; : 132452, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777007

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease. Little is known about how gene expression and chromatin structure are regulated in NAFLD due to lack of suitable model. Ducks naturally develop fatty liver similar to serious human non-alcoholic fatty liver (NAFL) without adipose inflammation and liver fibrosis, thus serves as a good model for investigating molecular mechanisms of adipose metabolism and anti-inflammation. Here, we constructed a NAFLD model without adipose inflammation and liver fibrosis in ducks. By performing dynamic pathological and transcriptomic analyses, we identified critical genes involving in regulation of the NF-κB and MHCII signaling, which usually lead to adipose inflammation and liver fibrosis. We further generated dynamic three-dimensional chromatin maps during liver fatty formation and recovery. This showed that ducks enlarged hepatocyte cell nuclei to reduce inter-chromosomal interaction, decompress chromatin structure, and alter strength of intra-TAD and loop interactions during fatty liver formation. These changes partially contributed to the tight control the NF-κB and the MHCII signaling. Our analysis uncovers duck chromatin reorganization might be advantageous to maintain liver regenerative capacity and reduce adipose inflammation. These findings shed light on new strategies for NAFLD control.

4.
Sleep Breath ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38772968

RESUMO

PURPOSE: Major Depressive Disorder (MDD) and Insomnia Disorder (ID) are prevalent psychiatric conditions often occurring concurrently, leading to substantial impairment in daily functioning. Understanding the neurobiological underpinnings of these disorders and their comorbidity is crucial for developing effective interventions. This study aims to analyze changes in functional connectivity within attention networks and default mode networks in patients with depression and insomnia. METHODS: The functional connectivity alterations in individuals with MDD, ID, comorbid MDD and insomnia (iMDD), and healthy controls (HC) were assessed from a cohort of 174 participants. They underwent rs-fMRI scans, demographic assessments, and scale evaluations for depression and sleep quality. Functional connectivity analysis was conducted using region-of-interest (ROI) and whole-brain methods. RESULTS: The MDD and iMDD groups exhibited higher Hamilton Depression Scale (HAMD) scores compared to HC and ID groups (P < 0.001). Both ID and MDD groups displayed enhanced connectivity between the left and right orbital frontal cortex compared to HC (P < 0.05), while the iMDD group showed reduced connectivity compared to HC and ID groups (P < 0.05). In the left insula, reduced connectivity with the right medial superior frontal gyrus was observed across patient groups compared to HC (P < 0.05), with the iMDD group showing increased connectivity compared to MDD (P < 0.05). Moreover, alterations in functional connectivity between the left thalamus and left temporal pole were found in iMDD compared to HC and MDD (P < 0.05). Correlation analyses revealed associations between abnormal connectivity and symptom severity in MDD and ID groups. CONCLUSIONS: Our findings demonstrate distinct patterns of altered functional connectivity in individuals with MDD, ID, and iMDD compared to healthy controls. These findings contribute to a better understanding of the pathophysiology of depression and insomnia, which could be used as a reference for the diagnosis and treatments of these patients.

5.
ACS Synth Biol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748665

RESUMO

Betulinic acid (BA) is a lupane-type triterpenoid with potent anticancer and anti-HIV activities. Its great potential in clinical applications necessitates the development of an efficient strategy for BA synthesis. This study attempted to achieve efficient BA biosynthesis in Saccharomyces cerevisiae using systematic metabolic engineering strategies. First, a de novo BA biosynthesis pathway in S. cerevisiae was constructed, which yielded a titer of 14.01 ± 0.21 mg/L. Then, by enhancing the BA synthesis pathway and dynamic inhibition of the competitive pathway, a greater proportion of the metabolic flow was directed toward BA synthesis, achieving a titer of 88.07 ± 5.83 mg/L. Next, acetyl-CoA and NADPH supply was enhanced, which increased the BA titer to 166.43 ± 1.83 mg/L. Finally, another BA synthesis pathway in the peroxisome was constructed. Dual regulation of the peroxisome and cytoplasmic metabolism increased the BA titer to 210.88 ± 4.76 mg/L. Following fed-batch fermentation process modification, the BA titer reached 682.29 ± 8.16 mg/L. Overall, this work offers a guide for building microbial cell factories that are capable of producing terpenoids with efficiency.

6.
Nat Commun ; 15(1): 2978, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582790

RESUMO

After decades of efforts, some fundamental physics for electrical switching of magnetization is still missing. Here, we report the discovery of the long-range intralayer Dzyaloshinskii-Moriya interaction (DMI) effect, which is the chiral coupling of orthogonal magnetic domains within the same magnetic layer via the mediation of an adjacent heavy metal layer. The effective magnetic field of the long-range intralayer DMI on the perpendicular magnetization is out-of-plane and varies with the interfacial DMI constant, the applied in-plane magnetic fields, and the magnetic anisotropy distribution. Striking consequences of the effect include asymmetric current/field switching of perpendicular magnetization, hysteresis loop shift of perpendicular magnetization in the absence of in-plane direct current, and sharp in-plane magnetic field switching of perpendicular magnetization. Utilizing the intralayer DMI, we demonstrate programable, complete Boolean logic operations within a single spin-orbit torque device. These results will stimulate investigation of the long-range intralayer DMI effect in a variety of spintronic devices.

7.
BMC Ophthalmol ; 24(1): 145, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38561680

RESUMO

BACKGROUND: The purpose of this study was to analyze myopic regression after corneal refractive surgery (CRS) in civilian pilots and to explore the factors that may cause long-term myopic regression. METHODS: We included civilian pilots who had undergone CRS to correct their myopia and who had at least 5 years of follow-up. We collected retrospective data and completed eye examinations and a questionnaire to assess their eye habits. RESULTS: A total of 236 eyes were evaluated in this study. 211 eyes had Intrastromal ablations (167 eyes had laser in situ keratomileusis, LASIK, 44 eyes had small incision lenticule extraction, SMILE) and 25 eyes had subepithelial ablations (15 eyes had laser epithelial keratomileusis, LASEK and 10 eyes had photorefractive keratectomy, PRK). The mean preoperative spherical equivalent (SE) was - 2.92 ± 1.11 D (range from - 1.00 to -5.00 D). A total of 56 eyes (23.6%) suffered from myopic regression after CRS. Comparisons of individual and eye characteristics between the regression and non-regression groups revealed statistically significant differences in age, cumulative flight time, postoperative SE (at 6 months and current), uncorrected visual acuity (UCVA), accommodative amplitude (AA), positive relative accommodation (PRA), postoperative period, types of CRS and eye habits. Generalized propensity score weighting (GPSW) was used to balance the distribution of covariates among different age levels, types of CRS, cumulative flying time, postoperative period and continuous near-work time. The results of GPS weighted logistic regression demonstrated that the associations between age and myopic regression, types of CRS and myopic regression, continuous near-work time and myopic regression were significant. Cumulative flying time and myopic regression, postoperative period and myopic regression were no significant. Specifically, the odds ratio (OR) for age was 1.151 (P = 0.022), and the OR for type of CRS was 2.769 (P < 0.001). The OR for continuous near-work time was 0.635 with a P value of 0.038. CONCLUSIONS: This is the first report to analyze myopic regression after CRS in civilian pilots. Our study found that for each year increase in age, the risk of civilian pilots experiencing myopic regression was increased. Intrastromal ablations had a lower risk of long-term myopia regression than subepithelial ablations. There is a higher risk of myopic progression with continuous near-work time > 45 min and poor accommodative function may be related factors in this specific population.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ , Miopia , Ceratectomia Fotorrefrativa , Humanos , Lactente , Estudos Retrospectivos , Córnea/cirurgia , Ceratectomia Fotorrefrativa/métodos , Acuidade Visual , Refração Ocular , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Resultado do Tratamento
8.
Mar Environ Res ; 197: 106481, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593647

RESUMO

Marine distribution of dimethylsulfoniopropionate (DMSP) and its cleavage product dimethyl sulfide (DMS) is greatly affected by the community structures of bacteria, phytoplankton, and zooplankton. Spatial distributions of dissolved and particulate DMSP (DMSPd,p), and DMS were measured and their relationships with DMSP lyase activity (DLA), abundance of DMSP-consuming bacteria (DCB), and the community structures of phytoplankton, zooplankton, and bacteria were determined during summer in the South China Sea (SCS). The depth distributions of DMSPd,p exhibited a similar trend with Chl a, reaching their maxima in the mixing layer. The DMS concentration was positively correlated with DCB abundance and DLA, indicating that DCB and DMSP lyase had a significant effect on DMS production. High DMS concentrations in the horizontal distribution coincided with high DCB abundance and DLA and may be due to the rapid growth of phytoplankton resulting from the high dissolved inorganic nitrogen concentration brought by the cold vortices. Moreover, the highest copepod abundance at station G3 coincided with the highest DMS concentrations there among stations B4, F2, and G3. These results suggest that copepod may play an important role in DMS production. The bacterial SAR11 clade was positively correlated with DLA, indicating its significant contribution to DMSP degradation in the SCS. These findings contribute to the understanding of the effect of the community assemblage on DMSP/DMS distributions in the SCS dominated by mesoscale vortices.


Assuntos
Água do Mar , Compostos de Sulfônio , Animais , Água do Mar/química , Enxofre/metabolismo , Compostos de Sulfônio/química , Compostos de Sulfônio/metabolismo , Sulfetos/metabolismo , Bactérias/metabolismo , Fitoplâncton , China , Zooplâncton/metabolismo
9.
Nucleic Acids Res ; 52(8): 4739-4755, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38567723

RESUMO

Mutagenesis driving genetic diversity is vital for understanding and engineering biological systems. However, the lack of effective methods to generate in-situ mutagenesis in multiple genomic loci combinatorially limits the study of complex biological functions. Here, we design and construct MultiduBE, a dCas12a-based multiplexed dual-function base editor, in an all-in-one plasmid for performing combinatorial in-situ mutagenesis. Two synthetic effectors, duBE-1a and duBE-2b, are created by amalgamating the functionalities of cytosine deaminase (from hAPOBEC3A or hAID*Δ ), adenine deaminase (from TadA9), and crRNA array processing (from dCas12a). Furthermore, introducing the synthetic separator Sp4 minimizes interference in the crRNA array, thereby facilitating multiplexed in-situ mutagenesis in both Escherichia coli and Bacillus subtilis. Guided by the corresponding crRNA arrays, MultiduBE is successfully employed for cell physiology reprogramming and metabolic regulation. A novel mutation conferring streptomycin resistance has been identified in B. subtilis and incorporated into the mutant strains with multiple antibiotic resistance. Moreover, surfactin and riboflavin titers of the combinatorially mutant strains improved by 42% and 15-fold, respectively, compared with the control strains with single gene mutation. Overall, MultiduBE provides a convenient and efficient way to perform multiplexed in-situ mutagenesis.


Assuntos
Bacillus subtilis , Sistemas CRISPR-Cas , Escherichia coli , Edição de Genes , Mutagênese , Escherichia coli/genética , Bacillus subtilis/genética , Edição de Genes/métodos , Plasmídeos/genética , Citosina Desaminase/genética , Citosina Desaminase/metabolismo , Mutação , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/genética , Aminoidrolases
10.
Sci China Life Sci ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38679670

RESUMO

Betaine-homocysteine methyltransferase (BHMT) regulates protein methylation and is correlated with tumorigenesis; however, the effects and regulation of BHMT in hepatocarcinogenesis remain largely unexplored. Here, we determined the clinical significance of BHMT in the occurrence and progression of hepatocellular carcinoma (HCC) using tissue samples from 198 patients. BHMT was to be frequently found (86.6%) expressed at relatively low levels in HCC tissues and was positively correlated with the overall survival of patients with HCC. Bhmt overexpression effectively suppressed several malignant phenotypes in hepatoma cells in vitro and in vivo, whereas complete knockout of Bhmt (Bhmt-/-) produced the opposite effect. We combined proteomics, metabolomics, and molecular biological strategies and detected that Bhmt-/- promoted hepatocarcinogenesis and tumor progression by enhancing the activity of glucose-6-phosphate dehydrogenase (G6PD) and PPP metabolism in DEN-induced HCC mouse and subcutaneous tumor-bearing models. In contrast, restoration of Bhmt with an AAV8-Bhmt injection or pharmacological inhibition of G6PD attenuated hepatocarcinogenesis. Additionally, coimmunoprecipitation identified monomethylated modifications of the G6PD, and BHMT regulated the methylation of G6PD. Protein sequence analysis, generation and application of specific antibodies, and site-directed mutagenesis indicated G6PD methylation at the arginine residue 246. Furthermore, we established bidirectionally regulated BHMT cellular models combined with methylation-deficient G6PD mutants to demonstrate that BHMT potentiated arginine methylation of G6PD, thereby inhibiting G6PD activity, which in turn suppressed hepatocarcinogenesis. Taken together, this study reveals a new methylation-regulatory mechanism in hepatocarcinogenesis owing to BHMT deficiency, suggesting a potential therapeutic strategy for HCC treatment.

11.
Animals (Basel) ; 14(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38672292

RESUMO

Eggshell gloss is an important characteristic for the manifestation of eggshell appearance. However, no study has yet identified potential candidate genes for eggshell gloss between high-gloss (HG) and low-gloss (LG) chickens. The aim of this study was to perform a preliminary investigation into the formation mechanism of eggshell gloss and to identify potential genes. The eggshell gloss of 300-day-old Rhode Island Red hens was measured from three aspects. Uterine tissues of the selected HG and LG (n = 5) hens were collected for RNA-seq. Blood samples were also collected for whole-genome resequencing (WGRS). RNA-seq analysis showed that 150 differentially expressed genes (DEGs) were identified in the uterine tissues of HG and LG hens. These DEGs were mainly enriched in the calcium signaling pathway and the neuroactive ligand-receptor interaction pathway. Importantly, these two pathways were also significantly enriched in the WGRS analysis results. Further joint analysis of WGRS and RNA-seq data revealed that 5-hydroxytryptamine receptor 1F (HTR1F), zinc finger protein 536 (ZNF536), NEDD8 ubiquitin-like modifier (NEDD8), nerve growth factor (NGF) and calmodulin 1 (CALM1) are potential candidate genes for eggshell gloss. In summary, our research provides a reference for the study of eggshell gloss and lays a foundation for improving egg glossiness in layer breeding.

12.
ESC Heart Fail ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629342

RESUMO

AIMS: In an era of evolving diagnostic possibilities, existing diagnostic systems are not fully sufficient to promptly recognize patients with early-stage hypertrophic cardiomyopathy (HCM) without symptomatic and instrumental features. Considering the sudden death of HCM, developing a novel diagnostic model to clarify the patients with early-stage HCM and the immunological characteristics can avoid misdiagnosis and attenuate disease progression. METHODS AND RESULTS: Three hundred eighty-five samples from four independent cohorts were systematically retrieved. The weighted gene co-expression network analysis, differential expression analysis (|log2(foldchange)| > 0.5 and adjusted P < 0.05), and protein-protein interaction network were sequentially performed to identify HCM-related hub genes. With a machine learning algorithm, the least absolute shrinkage and selection operator regression algorithm, a stable diagnostic model was developed. The immune-cell infiltration and biological functions of HCM were also explored to characterize its underlying pathogenic mechanisms and the immune signature. Two key modules were screened based on weighted gene co-expression network analysis. Pathogenic mechanisms relevant to extracellular matrix and immune pathways have been discovered. Twenty-seven co-regulated genes were recognized as HCM-related hub genes. Based on the least absolute shrinkage and selection operator algorithm, a stable HCM diagnostic model was constructed, which was further validated in the remaining three cohorts (n = 385). Considering the tight association between HCM and immune-related functions, we assessed the infiltrating abundance of various immune cells and stromal cells based on the xCell algorithm, and certain immune cells were significantly different between high-risk and low-risk groups. CONCLUSIONS: Our study revealed a number of hub genes and novel pathways to provide potential targets for the treatment of HCM. A stable model was developed, providing an efficient tool for the diagnosis of HCM.

13.
J Agric Food Chem ; 72(15): 8693-8703, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38574273

RESUMO

Ovalbumin (OVA) is the principal protein constituent of eggs. As an alternative to eggs, cell-cultured OVA can reduce the environmental impact of global warming and land use. Escherichia coli Nissle 1917 (EcN), a probiotic with specific endogenous cryptic plasmids that stably exist in cells without the addition of antibiotics, was chosen as the host for the efficient heterologous expression of the OVA. OVA yield reached 20 mg·L-1 in shake flasks using the OVA expression cassette containing a tac promoter (Ptac) upstream of the OVA-coding sequences on the endogenous plasmid pMUT2. Subsequently, we improved the level of the expression of the OVA by employing a dual promoter (PP5 combined with Ptac via a sigma factor binding site 24) and ribosome binding site (RBS) substitution. These enhancements increased the level of production of OVA in shake flasks to 30 and 42 mg·L-1, respectively. OVA by EcNP-P28 harboring plasmid L28 equipped with both dual promoter and the strong RBS8 reached 3.70 g·L-1 in a 3 L bioreactor. Recombinant OVA and natural OVA showed similar biochemical characteristics, including secondary structure, isoelectric point, amino acid composition, and thermal stability. This is currently the highest OVA production reported among prokaryotes. We successfully constructed an antibiotic-free heterologous protein expression system for EcN.


Assuntos
Escherichia coli , Probióticos , Escherichia coli/genética , Escherichia coli/metabolismo , Antibacterianos/metabolismo , Ovalbumina/genética , Ovalbumina/metabolismo , Plasmídeos/genética
14.
J Org Chem ; 89(10): 7047-7057, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38669210

RESUMO

An efficient method for the construction of C-P(V) and C-P(III) bonds via the iron-catalyzed phosphorylation of alcohols under ligand-free conditions is disclosed. This strategy represents a straightforward process to prepare a series of phosphine oxides and phosphine compounds in good to excellent yields from the readily available alcohols and P-H compounds. A plausible mechanism is also proposed. We anticipate that this mode of transforming simple alcohols would apply in chemical synthesis widely.

15.
J Virol ; 98(5): e0157323, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38572974

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and characterized by dysregulated immune response. Studies have shown that the SARS-CoV-2 accessory protein ORF7b induces host cell apoptosis through the tumor necrosis factor alpha (TNF-α) pathway and blocks the production of interferon beta (IFN-ß). The underlying mechanism remains to be investigated. In this study, we found that ORF7b facilitated viral infection and production, and inhibited the RIG-I-like receptor (RLR) signaling pathway through selectively interacting with mitochondrial antiviral-signaling protein (MAVS). MAVS439-466 region and MAVS Lys461 were essential for the physical association between MAVS and ORF7b, and the inhibition of the RLR signaling pathway by ORF7b. MAVSK461/K63 ubiquitination was essential for the RLR signaling regulated by the MAVS-ORF7b complex. ORF7b interfered with the recruitment of tumor necrosis factor receptor-related factor 6 (TRAF6) and the activation of the RLR signaling pathway by MAVS. Furthermore, interfering peptides targeting the ORF7b complex reversed the ORF7b-suppressed MAVS-RLR signaling pathway. The most potent interfering peptide V disrupts the formation of ORF7b tetramers, reverses the levels of the ORF7b-inhibited physical association between MAVS and TRAF6, leading to the suppression of viral growth and infection. Overall, this study provides a mechanism for the suppression of innate immunity by SARS-CoV-2 infection and the mechanism-based approach via interfering peptides to potentially prevent SARS-CoV-2 infection.IMPORTANCEThe pandemic coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and continues to be a threat to public health. It is imperative to understand the biology of SARS-CoV-2 infection and find approaches to prevent SARS-CoV-2 infection and ameliorate COVID-19. Multiple SARS-CoV-2 proteins are known to function on the innate immune response, but the underlying mechanism remains unknown. This study shows that ORF7b inhibits the RIG-I-like receptor (RLR) signaling pathway through the physical association between ORF7b and mitochondrial antiviral-signaling protein (MAVS), impairing the K63-linked MAVS polyubiquitination and its recruitment of tumor necrosis factor receptor-related factor 6 (TRAF6) to MAVS. The most potent interfering peptide V targeting the ORF7b-MAVS complex may reverse the suppression of the MAVS-mediated RLR signaling pathway by ORF7b and prevent viral infection and production. This study may provide new insights into the pathogenic mechanism of SARS-CoV-2 and a strategy to develop new drugs to prevent SARS-CoV-2 infection.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , COVID-19 , Proteína DEAD-box 58 , SARS-CoV-2 , Transdução de Sinais , Fator 6 Associado a Receptor de TNF , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Humanos , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Proteína DEAD-box 58/metabolismo , Células HEK293 , COVID-19/virologia , COVID-19/imunologia , COVID-19/metabolismo , Ubiquitinação , Receptores Imunológicos/metabolismo , Animais , Proteínas Virais Reguladoras e Acessórias/metabolismo , Proteínas Virais Reguladoras e Acessórias/genética , Interferon beta/metabolismo , Apoptose , Imunidade Inata , Fator de Necrose Tumoral alfa/metabolismo
16.
J Agric Food Chem ; 72(17): 9974-9983, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38625685

RESUMO

5-Methyltetrahydrofolate (5-MTHF) is the sole active form of folate functioning in the human body and is widely used as a nutraceutical. Unlike the pollution from chemical synthesis, microbial synthesis enables green production of 5-MTHF. In this study, Escherichia coli BL21 (DE3) was selected as the host. Initially, by deleting 6-phosphofructokinase 1 and overexpressing glucose-6-phosphate 1-dehydrogenase and 6-phosphogluconate dehydrogenase, the glycolysis pathway flux decreased, while the pentose phosphate pathway flux enhanced. The ratios of NADH/NAD+ and NADPH/NADP+ increased, indicating elevated NAD(P)H supply. This led to more folate being reduced and the successful accumulation of 5-MTHF to 44.57 µg/L. Subsequently, formate dehydrogenases from Candida boidinii and Candida dubliniensis were expressed, which were capable of catalyzing the reaction of sodium formate oxidation for NAD(P)H regeneration. This further increased the NAD(P)H supply, leading to a rise in 5-MTHF production to 247.36 µg/L. Moreover, to maintain the balance between NADH and NADPH, pntAB and sthA, encoding transhydrogenase, were overexpressed. Finally, by overexpressing six key enzymes in the folate to 5-MTHF pathway and employing fed-batch cultivation in a 3 L fermenter, strain Z13 attained a peak 5-MTHF titer of 3009.03 µg/L, the highest level reported in E. coli so far. This research is a significant step toward industrial-scale microbial 5-MTHF production.


Assuntos
Escherichia coli , Engenharia Metabólica , NADP , Oxirredução , Tetra-Hidrofolatos , Tetra-Hidrofolatos/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , NADP/metabolismo , Candida/metabolismo , Candida/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , NAD/metabolismo , Formiato Desidrogenases/metabolismo , Formiato Desidrogenases/genética
17.
Chem Sci ; 15(15): 5642-5652, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38638228

RESUMO

Passivation treatment is an effective method to suppress various defects in perovskite solar cells (PSCs), such as cation vacancies, under-coordinated Pb2+ or I-, and Pb-I antisite defects. A thorough understanding of the diversified impacts of different defect passivation methods (DPMs) on the device performance will be beneficial for making wise DPM choices. Herein, we choose a hydrophobic Lewis acid tris(pentafluorophenyl)borane (BCF), which can dissolve in both the perovskite precursor and anti-solvent, as the passivation additive. BCF treatment can immobilize organic cations via forming hydrogen bonds. Three kinds of DPMs based on BCF are applied to modify perovskite films in this work. It is found that the best DPM with BCF dissolved in anti-solvent can not only passivate multiple defects in perovskite, but also inhibit δ phase perovskite and improve the stability of devices. Meanwhile, DPM with BCF dissolved in both the perovskite precursor and anti-solvent can cause cracks and voids in perovskite films and deteriorate device performance, which should be avoided in practical applications. As a result, PSCs based on optimal DPMs of BCF present an increased efficiency of 22.86% with negligible hysteresis as well as improved overall stability. This work indicates that the selection and optimization of DPMs have an equally important influence on the photovoltaic performance of PSCs as the selection of passivation additives.

18.
Adv Healthc Mater ; : e2304136, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38551143

RESUMO

Oncolytic virus therapy is currently regarded as a promising approach in cancer immunotherapy. It has greater therapeutic advantages for colorectal cancer that is prone to distant metastasis. However, the therapeutic efficacy and clinical application of viral agents alone for colorectal cancer remain suboptimal. In this study, an engineered oncolytic vaccinia virus (OVV-Luc) that expresses the firefly luciferase gene is developed and loaded Chlorin e6 (Ce6) onto the virus surface through covalent coupling, resulting in OVV-Luc@Ce6 (OV@C). The OV@C infiltrates tumor tissue and induces endogenous luminescence through substrate catalysis, resulting in the production of reactive oxygen species. This unique system eliminates the need for an external light source, making it suitable for photodynamic therapy (PDT) in deep tissues. Moreover, this synergistic effect between PDT and viral immunotherapy enhances dendritic cell maturation, macrophage polarization, and reversal of the immunosuppressive microenvironment. This synergistic effect has the potential to convert a "cold" into a "hot" tumor, it offers valuable insights for clinical translation and application.

19.
Sci Total Environ ; 926: 172018, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547988

RESUMO

The improper disposal of large amounts of phosphogypsum generated during the production process of the phosphorus chemical industry (PCI) still exists. The leachate formed by phosphogypsum stockpiles could pose a threat to the ecological environment and human health. Nevertheless, information regarding the harmful effects of phosphogypsum leachate on organisms is still limited. Herein, the physicochemical characteristics of phosphogypsum leachate were analyzed, and its toxicity effect on zebrafish (Danio rerio), particularly in terms of hepatotoxicity and potential mechanisms, were evaluated. The results indicated that P, NH3-N, TN, F-, As, Cd, Cr, Co, Ni, Zn, Mn, and Hg of phosphogypsum leachate exceeded the V class of surface water environmental quality standards (GB 3838-2002) to varying degrees. Acute toxicity test showed that the 96 h LC50 values of phosphogypsum leachate to zebrafish was 2.08 %. Under exposure to phosphogypsum leachate, zebrafish exhibited concentration-dependent liver damage, characterized by vacuolization and infiltration of inflammatory cells. The increased in Malondialdehyde (MDA) content and altered activities of antioxidant enzymes in the liver indicated the induction of oxidative stress and oxidative damage. The expression of apoptosis-related genes (P53, PUMA, Caspase3, Bcl-2, and Bax) were up-regulated at low dosage group and down-regulated at medium and high dosage groups, suggesting the occurrence of hepatocyte apoptosis or necrosis. Additionally, phosphogypsum leachate influenced the composition of the zebrafish gut microbiota by reducing the relative abundance of Bacteroidota, Aeromonas, Flavobacterium, Vibrio, and increasing that of Rhodobacter and Pirellula. Correlation analysis revealed that gut microbiota dysbiosis was associated with phosphogypsum leachate-induced hepatotoxicity. Altogether, exposure to phosphogypsum leachate caused liver damage in zebrafish, likely through oxidative stress and apoptosis, with the intestinal flora also playing a significant role. These findings contribute to understanding the ecological toxicity of phosphogypsum leachate and promote the sustainable development of PCI.


Assuntos
Sulfato de Cálcio , Doença Hepática Induzida por Substâncias e Drogas , Poluentes Químicos da Água , Animais , Humanos , Peixe-Zebra/metabolismo , Estresse Oxidativo , Fósforo/metabolismo , Poluentes Químicos da Água/metabolismo
20.
Int Immunopharmacol ; 130: 111765, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447414

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) displayed poor response to programmed death-1 (PD-1) blockade therapy. Regulatory T cells (Tregs) was one of major immunosuppressive components in Tumor microenvironment and plays a vital role in the resistance of immunotherapy. Coinhibitory receptors regulate function of regulatory Tregs and are associated with resistance of PD-1 blockade. However, the coinhibitory receptors expression and differentiated status of Tregs in AML patients remain to be unclear. METHODS: Phenotypic determination of Tregs and CD8+ T cells in bone marrow of healthy donors and AML patients was performed by flow cytometry. Coculture experiments of AML and Tregs in vitro were performed and the concentrations of lactate acid (LA) in the supernatant were examined by ELISA. RESULTS: More Tregs differentiated into effector subsets in AML patients. However, PD-1 and T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) expression on Tregs were comparable in healthy donors and AML patients. Further analysis showed that PD-1+ and PD-1+TIGIT+Tregs are more abundant in the bone marrow of patients with higher leukemic load. Moreover, PD-1+ Tregs accumulation was associated with higher level of senescent CD4+ T cells and increased frequencies of exhausted CD4+ as well as CD8+ T cells. Notably, neither Tregs nor their effector subsets were decreased among patients in complete remission. PD-1 expression was significantly downregulated in Tregs after achieving complete remission. Mechanistically, both AML cell line (KG-1α) and primary AML blasts produced high concentration of LA. Blockade of LA by lactate transporter inhibitor abrogated the upregulation of PD-1 by AML cells. CONCLUSION: PD-1+ Tregs accumulation in bone marrow in higher leukemic burden setting was linked to lactate acid secreted by AML blasts and decreased after disease remission. Our findings provided a novel insight into Tregs in AML and possible mechanism for resistance of PD-1 blockade in AML.


Assuntos
Medula Óssea , Leucemia Mieloide Aguda , Humanos , Medula Óssea/patologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Ácido Láctico , Carga Tumoral , Leucemia Mieloide Aguda/metabolismo , Microambiente Tumoral
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