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1.
Nature ; 629(8011): 467-473, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38471529

RESUMO

Prokaryotes have evolved intricate innate immune systems against phage infection1-7. Gabija is a highly widespread prokaryotic defence system that consists of two components, GajA and GajB8. GajA functions as a DNA endonuclease that is inactive in the presence of ATP9. Here, to explore how the Gabija system is activated for anti-phage defence, we report its cryo-electron microscopy structures in five states, including apo GajA, GajA in complex with DNA, GajA bound by ATP, apo GajA-GajB, and GajA-GajB in complex with ATP and Mg2+. GajA is a rhombus-shaped tetramer with its ATPase domain clustered at the centre and the topoisomerase-primase (Toprim) domain located peripherally. ATP binding at the ATPase domain stabilizes the insertion region within the ATPase domain, keeping the Toprim domain in a closed state. Upon ATP depletion by phages, the Toprim domain opens to bind and cleave the DNA substrate. GajB, which docks on GajA, is activated by the cleaved DNA, ultimately leading to prokaryotic cell death. Our study presents a mechanistic landscape of Gabija activation.


Assuntos
Bacillus cereus , Proteínas de Bactérias , Bacteriófagos , Microscopia Crioeletrônica , Imunidade Inata , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/química , Adenosina Trifosfatases/ultraestrutura , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Apoproteínas/química , Apoproteínas/imunologia , Apoproteínas/metabolismo , Apoproteínas/ultraestrutura , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/ultraestrutura , Bacteriófagos/imunologia , DNA/metabolismo , DNA/química , Clivagem do DNA , Magnésio/química , Magnésio/metabolismo , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Viabilidade Microbiana , Bacillus cereus/química , Bacillus cereus/imunologia , Bacillus cereus/metabolismo , Bacillus cereus/ultraestrutura , Estrutura Quaternária de Proteína , DNA Primase/química , DNA Primase/metabolismo , DNA Primase/ultraestrutura , DNA Topoisomerases/química , DNA Topoisomerases/metabolismo , DNA Topoisomerases/ultraestrutura
2.
Artigo em Inglês | MEDLINE | ID: mdl-38305772

RESUMO

Three Gram-stain-negative, rod-shaped, non-spore-forming bacteria were isolated from activated sludge samples. The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that the three strains, designated HXWNR29T, HXWNR69T and HXWNR70T, had the highest sequence similarity to the type strains Flavobacterium cheniae NJ-26T, Flavobacterium channae KSM-R2A30T and Flavobacterium amniphilum KYPY10T with similarities of 97.66 %, 98.66 and 98.14 %, respectively. The draft genomes of these three strains were 2.93 Mbp (HXWNR29T), 2.69 Mbp (HXWNR69T) and 2.65 Mbp (HXWNR70T) long with DNA G+C contents of 31.84 %, 32.83 % and 34.66 %, respectively. These genomes contained many genes responsible for carbohydrate degradation and antibiotic resistance. The major fatty acids (>5 %) included iso-C15 : 0, iso-C15 : 0 3-OH and iso-C17 : 0 3-OH. The major menaquinone was MK-6 for all the three strains. The average nucleotide identity (ANI; 72.7-88.5 %) and digital DNA-DNA hybridization (dDDH; 19.6-35.3 %) results further indicated that these three strains represented three novel species within the genus Flavobacterium, for which the names Flavobacterium odoriferum sp. nov. (type strain HXWNR29T = KCTC 92446T = CGMCC 1.61821T), Flavobacterium fragile sp. nov. (type strain HXWNR69T = KCTC 92468T = CGMCC 1.61442T) and Flavobacterium luminosum sp. nov. (type strain HXWNR70T = KCTC 92447T = CGMCC 1.61443T) are proposed.


Assuntos
Ácidos Graxos , Flavobacterium , Ácidos Graxos/química , Esgotos , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Vitamina K 2
3.
Anal Chem ; 95(12): 5256-5266, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36917632

RESUMO

Myxobacteria are fascinating prokaryotes featuring a potent capacity for producing a wealth of bioactive molecules with intricate chemical topology as well as intriguing enzymology, and thus it is critical to developing an efficient pipeline for bioprospecting. Herein, we construct the database MyxoDB, the first public compendium solely dedicated to myxobacteria, which enabled us to provide an overview of the structural diversity and taxonomic distribution of known myxobacterial natural products. Moreover, we demonstrated that the cutting-edge NMR-based metabolomics was effective to differentiate the biosynthetic priority of myxobacteria, whereby MyxoDB could greatly streamline the dereplication of multifarious known compounds and accordingly speed up the discovery of new compounds. This led to the rapid identification of a class of linear di-lipopeptides (archangimins) and a rare rearranged sterol (corasterol) that were endowed with unique chemical architectures and/or biosynthetic enzymology. We also showcased that NMR-based metabolomics, MyxoDB, and genomics can also work concertedly to accelerate the targeted discovery of a polyketidic compound pyxipyrrolone C. All in all, this study sets the stage for the discovery of many more novel natural products from underexplored myxobacterial resources.


Assuntos
Produtos Biológicos , Myxococcales , Produtos Biológicos/química , Bioprospecção , Imageamento por Ressonância Magnética , Metabolômica
4.
Artigo em Inglês | MEDLINE | ID: mdl-35666677

RESUMO

Two Gram-negative, rod-shaped, non-spore-forming bacteria, designated SM9T and SM2T, were isolated from Taklamakan Desert soil samples. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strains SM9T and SM2T had the highest sequence similarity to the type strains Microvirga indica BCRC 80972T and Microvirga soli NBRC 112417T with similarity values of 98.2 and 97.7 %, respectively, and Microvirga was among the predominant genera in the desert soil. The draft genomes of these two strains were 4.56 Mbp (SM9T) and 5.08 Mbp (SM2T) long with 65.1 mol% (SM9T) and 63.5 mol% (SM2T) G+C content. To adapt to the desert environment, these two strains possessed pathways for the synthesis of stress metabolite trehalose. The major fatty acids (>5 %) included C18 : 1 ω9c in SM2T, but C16 : 0, C18 : 0 and C19 : 0 cyclo ω8c in SM9T, while the major menaquinone was ubiquinone 10 in both strains. The major polar lipids of SM9T and SM2T were phosphatidylglycerol, phosphatidylethanolamine and phospholipid. The average nucleotide identity and digital DNA-DNA hybridization results further indicated that strains SM9T and SM2T were distinguished from phylogenetically related species and represented two novel species within the genus Microvirga, for which the names Microvirga roseola sp. nov. (type strain SM2T=KCTC 72792T=CGMCC 1.17776T) and Microvirga lenta sp. nov. (type strain SM9T=KCTC 82729T=CCTCC AB 2021131T) are proposed.


Assuntos
Bradyrhizobiaceae , Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Bradyrhizobiaceae/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo
5.
Artigo em Inglês | MEDLINE | ID: mdl-35482520

RESUMO

A Gram-stain-negative, non-motile, moderately halophilic and facultatively anaerobic bacterium, designated YR4-1T, was isolated from a saline-alkali and sorghum-planting soil sample collected in Dongying, Shandong Province, PR China. Growth occurred at 28-45 °C with the presence of 4.0-20.0 % (w/v) NaCl and pH 6.0-9.0. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that YR4-1T shared the highest similarity of 92.1-92.4 % with the valid published species of Aliifodinibius. The isolate formed a separate clade at the genus level in recently described family Balneolaceae. The draft genome of strain YR4-1T is 3.83 Mbp long with 44.0 mol% G+C content. The strain possesses several genes involved in the osmotic stress response mechanism and diverse metabolic pathways, probably for the living in saline environment. This may lead to a better understanding of the underrepresented Balneolaceae lineage. The major menaquinone was MK-7. The main polar lipid profile was composed of diphosphatidylglycerol, phosphatidylglycerol, phosphoglycolipids, aminophosphoglycolipid, one glycolipid, and four unidentified lipids. The predominant cellular fatty acids were iso-C15 : 0 (35.7 %) and anteiso-C15 : 0 (33.5 %). On the basis of its phenotypic, chemotaxonomic and phylogenetic features, strain YR4-1T represents a novel species of a new genus, for which the name Halalkalibacterium roseum gen. nov., sp. nov. is proposed. The type strain is YR4-1T (=CGMCC 1.17777T=KCTC 72795T).


Assuntos
Ácidos Graxos , Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Int J Mol Sci ; 23(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36077020

RESUMO

The NAC (NAM, ATAF1/2, and CUC2) transcription factors are one of the largest families of transcription factors in plants and play an important role in plant development and the response to adversity. In this study, we cloned a new NAC gene, SlNAC10, from the halophyte Suaeda liaotungensis K. The gene has a total length of 1584 bp including a complete ORF of 1107 bp that encodes 369 amino acids. The SlNAC10-GFP fusion protein is located in the nucleus and SlNAC10 has a transcription activation structural domain at the C-terminus. We studied the expression characteristics of SlNAC10 and found that it was highest in the leaves of S. liaotungensis and induced by drought, salt, cold, and abscisic acid (ABA). To analyze the function of SlNAC10 in plants, we obtained SlNAC10 transgenic Arabidopsis. The growth characteristics and physiological indicators of transgenic Arabidopsis were measured under salt and drought stress. The transgenic Arabidopsis showed obvious advantages in the root length and survival rate; chlorophyll fluorescence levels; and the antioxidant enzyme superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, and the proline content was higher than that of the wild-type (WT) Arabidopsis, whereas the relative electrolyte leakage and malondialdehyde (MDA) content were lower than those of the wild-type Arabidopsis. We explored the regulatory role of SlNAC10 on proline synthesis-related enzyme genes and found that SlNAC10 binds to the AtP5CS1, AtP5CS2, and AtP5CR promoters and regulates their downstream gene transcription. To sum up, SlNAC10 as a transcription factor improves salt and drought tolerance in plants possibly by regulating proline synthesis.


Assuntos
Arabidopsis , Chenopodiaceae , Arabidopsis/metabolismo , Chenopodiaceae/genética , Chenopodiaceae/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Prolina/metabolismo , Cloreto de Sódio/metabolismo , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
New Phytol ; 211(1): 138-48, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26879496

RESUMO

We recently identified a defense-related tomato (Solanum lycopersicum) NAC (NAM, ATAF1,2, CUC2) transcription factor, NAC1, that is subjected to ubiquitin-proteasome system-dependent degradation in plant cells. In this study, we identified a tomato ubiquitin ligase (termed SEVEN IN ABSENTIA3; SINA3) that ubiquitinates NAC1, promoting its degradation. We conducted coimmunoprecipitation and bimolecular fluorescence complementation to determine that SINA3 specifically interacts with the NAC1 transcription factor in the nucleus. Moreover, we found that SINA3 ubiquitinates NAC1 in vitro and promotes NAC1 degradation via polyubiquitination in vivo, indicating that SINA3 is a ubiquitin ligase that ubiquitinates NAC1, promoting its degradation. Our real-time PCR analysis indicated that, in contrast to our previous finding that NAC1 mRNA abundance increases upon Pseudomonas infection, the SINA3 mRNA abundance decreases in response to Pseudomonas infection. Moreover, using Agrobacterium-mediated transient expression, we found that overexpression of SINA3 interferes with the hypersensitive response cell death triggered by multiple plant resistance proteins. These results suggest that SINA3 ubiquitinates a defense-related NAC transcription factor for degradation and plays a negative role in defense signaling.


Assuntos
Proteínas de Plantas/metabolismo , Solanum lycopersicum/fisiologia , Fatores de Transcrição/metabolismo , Núcleo Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteólise , Pseudomonas/patogenicidade , Transdução de Sinais , Nicotiana/genética , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
9.
Int J Mol Sci ; 16(11): 26582-98, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26556351

RESUMO

Rapid and complex immune responses are induced in plants upon pathogen recognition. One form of plant defense response is a programmed burst in transcription and translation of pathogenesis-related proteins, of which many rely on ER processing. Interestingly, several ER stress marker genes are up-regulated during early stages of immune responses, suggesting that enhanced ER capacity is needed for immunity. Eukaryotic cells respond to ER stress through conserved signaling networks initiated by specific ER stress sensors tethered to the ER membrane. Depending on the nature of ER stress the cell prioritizes either survival or initiates programmed cell death (PCD). At present two plant ER stress sensors, bZIP28 and IRE1, have been described. Both sensor proteins are involved in ER stress-induced signaling, but only IRE1 has been additionally linked to immunity. A second branch of immune responses relies on PCD. In mammals, ER stress sensors are involved in activation of PCD, but it is unclear if plant ER stress sensors play a role in PCD. Nevertheless, some ER resident proteins have been linked to pathogen-induced cell death in plants. In this review, we will discuss the current understanding of plant ER stress signaling and its cross-talk with immune signaling.


Assuntos
Estresse do Retículo Endoplasmático , Imunidade Vegetal , Fenômenos Fisiológicos Vegetais , Transdução de Sinais , Animais , Apoptose , Interações Hospedeiro-Patógeno
10.
Drug Des Devel Ther ; 18: 2775-2791, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38984208

RESUMO

Background: Psoriasis is a common chronic inflammatory skin condition. The emergence of psoriasis has been linked to dysbiosis of the microbiota on the skin surface and an imbalance in the immunological microenvironment. In this study, we investigated the therapeutic impact of topical thymopentin (TP5) on imiquimod (IMQ)-induced psoriasis in mice, as well as the modulatory influence of TP5 on the skin immune milieu and the skin surface microbiota. Methods: The IMQ-induced psoriasis-like lesion mouse model was used to identify the targets and molecular mechanisms of TP5. Immunofluorescence was employed to identify differences in T-cell subset expression before and after TP5 therapy. Changes in the expression of NF-κB signaling pathway components were assessed using Western blotting (WB). 16S rRNA sequencing and network pharmacology were used to detect changes in the skin flora before and after TP5 administration. Results: In vivo, TP5 reduced IMQ-induced back inflammation in mice. H&E staining revealed decreased epidermal thickness and inflammatory cell infiltration with TP5. Masson staining revealed decreased epidermal and dermal collagen infiltration after TP5 administration. Immunohistochemistry showed that TP5 treatment dramatically reduced IL-17 expression. Results of the immunoinfiltration analyses showed psoriatic lesions with more T-cell subsets. According to the immunofluorescence results, TP5 dramatically declined the proportions of CD4+, Th17, ROR+, and CD8+ T cells. WB revealed that TP5 reduced NF-κB pathway expression in skin tissues from IMQ-induced psoriasis model mice. 16S rRNA sequencing revealed a significant increase in Burkholderia and Pseudomonadaceae_Pseudomonas and a significant decrease in Staphylococcaceae_Staphylococcus, Aquabacterium, Herbaspirillum, and Balneimonas. Firmicutes dominated the skin microbial diversity after TP5 treatment, while Bacteroidetes, Verrucomicrobia, TM7, Proteobacteria, Actinobacteria, Acidobacteria, Gemmatimonadetes, and other species dominated in the IMQ group. Conclusion: TP5 may treat psoriasis by modulating the epidermal flora, reducing NF-κB pathway expression, and influencing T-cell subsets.


Assuntos
Imiquimode , Psoríase , Pele , Timopentina , Psoríase/tratamento farmacológico , Psoríase/induzido quimicamente , Psoríase/imunologia , Psoríase/patologia , Animais , Camundongos , Pele/efeitos dos fármacos , Pele/patologia , Imiquimode/farmacologia , Timopentina/farmacologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Feminino , Microbiota/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL
11.
Noncoding RNA Res ; 9(3): 901-912, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38616861

RESUMO

Background: DNA methylation is a crucial epigenetic alteration involved in diverse biological processes and diseases. Nevertheless, the precise role of DNA methylation in chemotherapeutic drug-induced alopecia remains unclear. This study examined the role and novel processes of DNA methylation in regulating of chemotherapeutic drug-induced alopecia. Methods: A mouse model of cyclophosphamide (CTX)-induced alopecia was established. Hematoxylin-eosin staining and immunohistochemical staining for the Ki67 proportion and a mitochondrial membrane potential assay (JC-1) were performed to assess the structural integrity and proliferative efficiency of the hair follicle stem cells (HFSCs). Immunofluorescence staining and real-time fluorescence quantitative PCR (RT-qPCR) were performed to determine the expression levels of key HFSC markers, namely Lgr5, CD49f, Sox9, CD200, and FZD10. Differential DNA methylation levels between the normal and CTX-induced model groups were determined through simple methylation sequencing and analyzed using bioinformatics tools. The expression levels of miR-365-1, apoptosis markers, and DAP3 were detected through RT-qPCR and western blotting. In parallel, primary mouse HFSCs were extracted and used as a cell model, which was constructed using 4-hydroperoxycyclophosphamide. The luciferase reporter gene assay was conducted to confirm miR-365-1 binding to DAP3. To measure the expression of relevant indicators, superoxide dismutase (SOD) and malondialdehyde (MDA) kits were used. Methylation-specific PCR (MS-PCR) was performed to determine DNA methylation levels. The regulatory relationship within HFSCs was confirmed through plasmid overexpression of miR-365-1 and DAP3. Result: In the alopecia areata model, a substantial number of apoptotic cells were observed within the hair follicles on the mouse backs. Immunofluorescence staining revealed that the expression of HFSC markers significantly reduced in the CTX group. Both RT-qPCR and western blotting demonstrated a noteworthy difference in DNA methyltransferase expression. Simple methylation sequencing unveiled that DNA methylation substantially increased within the dorsal skin of the CTX group. Subsequent screening identified miR-365-1 as the most differentially expressed miRNA. miR-365-1 was predicted and confirmed to bind to the target gene DAP3. In the CTX group, SOD and ATP expression markedly reduced, whereas MDA levels were significantly elevated. Cellular investigations revealed 4-HC-induced cell cycle arrest and decreased expression of HFSC markers. MS-PCR indicated hypermethylation modification of miR-365-1 in the 4-HC-induced HFSCs. The luciferase reporter gene experiment confirmed the binding of miR-365-1 to the DAP3 promoter region. miR-365-1 overexpression dramatically reduced apoptotic protein expression in the HFSCs. However, this effect was slightly reversed after DAP3 overexpression in lentivirus. Conclusion: This study explored the occurrence of miR-365-1 DNA methylation in chemotherapeutic drug-induced alopecia. The results unveiled that miR-365-1 reduces cell apoptosis by targeting DAP3 in HFSCs, thereby revealing the role of DNA methylation of the miR-365-1 promoter in chemotherapeutic drug-induced alopecia.

12.
Phytomedicine ; 132: 155856, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39024674

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a common skin condition that causes chronic and recurring eczema lesions. Prior research has indicated that Cannabis fructus, the mature fruit of Cannabis sativa, has an antioxidant effect. Historically, Cannabis fructus has been used in cosmetics and medicine. However, there is limited knowledge regarding its biological components and the mechanisms by which it prevents and treats AD. OBJECTIVES: HPLC-ESI-MS/MS analysis was utilized to identify the main compounds of Cannabis fructus, and trilinolein was extracted using chromatographic techniques. The potential of trilinolein in the prevention of AD was assessed, and its underlying mechanisms of action were elucidated. METHODS: The distribution of distinct cellular subpopulations and the principal biological processes implicated in the pathogenesis of AD were assessed through a comparative study involving chronic AD patients and healthy controls (HCs). Differential gene expression was validated in clinical samples from the lesions of AD patients and the healthy skin of controls. The pharmacodynamic activity of trilinolein was validated in dinitrochlorobenzene (DNCB)-induced BALB/c mice and in IL-4- and TNF-α-induced HaCaT cells. Proteomics analyse was employed to investigate its mechanisms. RESULTS: Single-cell transcriptome analysis revealed that chronic AD is characterized by abnormal keratinocyte differentiation and oxidative stress damage. When topically applied, trilinolein can effectively improve AD-like skin lesions induced by DNCB. It increases the expression of terminal differentiation proteins and decreases the expression of NADPH oxidase 2 (NOX2), with a therapeutic effect comparable to that of the positive control drug crisaborole. Additionally, trilinolein reduced ROS fluorescence intensity, restored mitochondrial morphology and membrane potential, and decreased mitochondrial DNA (mtDNA) release in keratinocytes stimulated with IL-4 and TNF-α. Moreover, trilinolein increased the protein expression of AhR, CYP1A1, and Nrf2 in a dose-dependent manner. The effect of trilinolein on keratinocyte terminal differentiation proteins and ROS levels was blocked by the addition of an AhR inhibitor. CONCLUSION: The study suggests that trilinolein from Cannabis fructus alleviates NOX2-dependent mitochondrial dysfunction and repair the skin barrier via AhR-Nrf2 pathway, making it a promising agent for the prevention and treatment of AD.

13.
Biochem Biophys Res Commun ; 431(3): 501-5, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23333384

RESUMO

The highly conserved eukaryotic co-chaperone SGT1 (suppressor of the G2 allele of skp1) is an important signaling component of plant defense responses and positively regulates disease resistance conferred by many resistance (R) proteins. In this study, we investigated the contribution of SGT1 in the Prf-mediated defense responses in both Nicotiana benthamiana and tomato (Solanum lycopersicum). SGT1 was demonstrated to interact with Prf in plant cells by co-immunoprecipitation. The requirement of SGT1 in the accumulation of Prf or autoactive Prf(D1416V) was determined by the degradation of these proteins in N. benthamiana, in which SGT1 was repressed by virus-induced gene silencing (VIGS). Pseudomonas pathogen assay on the SGT1-silenced tomato plants implicates SGT1 is required for the Prf-mediated full resistance to Pseudomonas syringae pv. tomato (Pst). These results suggest that, in both N. benthamiana and tomato, SGT1 contributes to the Prf-mediated defense responses by stabilizing Prf protein via its co-chaperone activity.


Assuntos
Chaperonas Moleculares/metabolismo , Nicotiana/microbiologia , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Pseudomonas syringae , Solanum lycopersicum/microbiologia , Apoptose , Solanum lycopersicum/metabolismo , Transdução de Sinais , Nicotiana/metabolismo
14.
Colloids Surf B Biointerfaces ; 223: 113149, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36706480

RESUMO

Noninvasive human health monitoring requires the development of efficient electrochemical sensors for the quantitative analysis of infinitesimal biomolecules. In this work, we reported a novel hierarchical nanosheet assemblies (HSA) of copper-based metal-organic frameworks (MOFs) as an electrochemical sensor for ascorbic acid (AA) detection. Copper 1,4-benzenedicarboxylate (CuBDC) HSA was constructed by three steps of in situ growth on stone paper, including hydrolysis, anion exchange, and heteroepitaxy growth. The monodispersed two-dimensional MOFs nanosheet units were aligned in an orderly manner and arranged into three-dimensional hierarchical assemblies. The CuBDC HSA-based AA sensor displayed a high sensitivity of 396.8 µA mM-1 cm-2 and a low detection limit of 0.1 µM. Excellent selectivity, stability and reproducibility were also obtained. Benefiting from the advantages of ultrathin nanosheets and nature-inspired hierarchy, this unique architecture facilitated reactant dispersion and maximized the accessible active sites and charge-transport capability and thus had superior catalytic ability for the electro-oxidation of ascorbic acid compared to bulk MOFs. Moreover, the CuBDC HSA sensor performed AA level detection in juice samples with acceptable accuracy and verified the feasibility for sweat AA sensing. This novel MOFs architecture holds great potential as an electrochemical sensor to detect AA for noninvasive human health monitoring in the future.


Assuntos
Cobre , Estruturas Metalorgânicas , Humanos , Cobre/química , Estruturas Metalorgânicas/química , Ácido Ascórbico/análise , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodos
15.
Imeta ; 2(4): e133, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38868220

RESUMO

The prevalence of cadmium (Cd)-polluted agricultural soils is increasing globally, and arbuscular mycorrhizal fungi (AMF) can reduce the absorption of heavy metals by plants and improve mineral nutrition. However, the immobilization of the rhizosphere on cadmium is often overlooked. In this study, Glomus mosseae and Medicago sativa were established as symbiotes, and Cd migration and environmental properties in the rhizosphere were analyzed. AMF reduced Cd migration, and Cd2+ changed to an organic-bound state. AMF symbiosis treatment and Cd exposure resulted in microbial community variation, exhibiting a distinct deterministic process (|ßNTI| > 2), which ultimately resulted in a core microbiome function of heavy metal resistance and nutrient cycling. AMF increased available N and P, extracellular enzyme activity (LaC, LiP, and CAT), organic matter content (TOC, EOC, and GRSP), and Eh of the rhizosphere soil, significantly correlating with decreased Cd migration (p < 0.05). Furthermore, AMF significantly affected root metabolism by upregulating 739 metabolites, with flavonoids being the main factor causing microbiome variation. The structural equation model and variance partial analysis revealed that the superposition of the root metabolites, microbial, and soil exhibited the maximum explanation rate for Cd migration reduction (42.4%), and the microbial model had the highest single explanation rate (15.5%). Thus, the AMF in the rhizosphere microenvironment can regulate metabolite-soil-microbial interactions, reducing Cd migration. In summary, the study provides a new scientific explanation for how AMF improves plant Cd tolerance and offers a sustainable solution that could benefit both the environment and human health.

16.
Nat Commun ; 14(1): 4534, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37500635

RESUMO

Locomotor activities can enhance learning, but the underlying circuit and synaptic mechanisms are largely unknown. Here we show that locomotion facilitates aversive olfactory learning in C. elegans by activating mechanoreceptors in motor neurons, and transmitting the proprioceptive information thus generated to locomotion interneurons through antidromic-rectifying gap junctions. The proprioceptive information serves to regulate experience-dependent activities and functional coupling of interneurons that process olfactory sensory information to produce the learning behavior. Genetic destruction of either the mechanoreceptors in motor neurons, the rectifying gap junctions between the motor neurons and locomotion interneurons, or specific inhibitory synapses among the interneurons impairs the aversive olfactory learning. We have thus uncovered an unexpected role of proprioception in a specific learning behavior as well as the circuit, synaptic, and gene bases for this function.


Assuntos
Caenorhabditis elegans , Junções Comunicantes , Animais , Caenorhabditis elegans/genética , Junções Comunicantes/fisiologia , Interneurônios/fisiologia , Propriocepção/fisiologia , Aprendizagem da Esquiva , Locomoção/fisiologia
17.
Nanoscale Adv ; 4(6): 1545-1550, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36134365

RESUMO

Racetrack memory with the advantages of small size and high reading speed is proposed based on current-induced domain wall (DW) motion in a ferromagnetic (FM) nanowire. Walker breakdown that restricts the enhancement of DW velocity in a single FM nanowire can be depressed by inter-wire magnetostatic coupling in a double FM nanowire system. However, this magnetostatic coupling also limits the working current density in a small range. In the present work, based on micromagnetic calculation, we have found that when there is a moderate difference of magnetic anisotropy constant between two FM nanowires, the critical current density for triggering the DW motion can be reduced while that for breaking the inter-wire coupling can be enhanced significantly to a magnitude of 1013 A m-2, which is far above the working current density in current electronic devices. The manipulation of working current density is relevant to the modification of DW structure and inter-wire magnetostatic coupling due to the difference of the anisotropy constants between the two nanowires and paves a way to develop racetrack memory that can work in a wide range of current.

18.
Zhongguo Zhen Jiu ; 42(6): 673-5, 2022 Jun 12.
Artigo em Zh | MEDLINE | ID: mdl-35712953

RESUMO

The paper introduces professor GAO Shu-zhong's understanding on "seeking yin from yang needling method" and its clinical application on the basis of "qi street" and "four seas" theories. Through professor GAO's clinical practice for years, he integrates and extendes the theories of "seeking yin from yang", "qi street" and "four seas" in Huangdi Neijing (The Yellow Emperor's Inner Classic). In this specific acupuncture method, in reference with the theories of "qi street" and "four seas", acupuncture is exerted on yang part of body, e.g. the back and lumber region to treat the diseases of yin parts, e.g. the chest and abdomen, which is differentiated as yin-yang imbalance in pathogenesis. In order to fully explain the clinical curative effect of "seeking yin from yang needling method", the common diseases in clinic, e.g. the disorders of heart, spleen and stomach systems, as well as the gynecology are taken as examples in the paper.


Assuntos
Terapia por Acupuntura , Acupuntura , Terapia por Acupuntura/história , Humanos , Masculino , Qi , Procedimentos Cirúrgicos Vasculares , Yin-Yang
19.
Medicine (Baltimore) ; 100(49): e28080, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34889257

RESUMO

BACKGROUND: Adenomyosis (AM) is a disease in which the endometrium (including glands and stroma) invades the myometrium and grows. The main clinical symptoms include menorrhagia, dysmenorrhea, chronic pelvic pain, metrorrhagia, and dyspareunia, which will seriously affect the physical and mental health of patients, and most of which occur in women of childbearing age. Acupuncture, as a special external treatment of Traditional Chinese medicine, has shown good effects in the treatment of adenomyosis. At present, there is a lack of systematic review on acupuncture in the treatment of adenomyosis. We conduct this study to evaluate the efficacy and safety of acupuncture in the treatment of adenomyosis. METHODS: We will search Chinese and English databases: Medline, Pubmed, EMBASE, Cochrane library, China National Knowledge Infrastructure (CNKI), Chinese Scientific and Journal Database, Wan Fang database (Wanfang), Chinese Biomedical Literature Database (CBM) to identify articles of randomized clinical trials of acupuncture for adenomyosis. All above electronic databases will be searched from inception to September 30, 2021. RevMan 5.3 software will be used to conduct this systematic review. No language and publication status restrictions will be applied. RESULTS: The study will prove the efficacy and safety of acupuncture for adenomyosis. CONCLUSION: We plan to submit this systematic review to a peer-reviewed journal. TRIAL REGISTRATION NUMBER: CRD42021277136.


Assuntos
Terapia por Acupuntura , Adenomiose/terapia , Dismenorreia/terapia , Feminino , Humanos , Infertilidade/terapia , Menorragia/terapia , Metanálise como Assunto , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
20.
Syst Appl Microbiol ; 44(6): 126274, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34763291

RESUMO

Polyangium belongs to Polyangiaceae family of Myxococcales, a taxonomic group well-known for their extraordinary social lifestyle and diverse novel gene clusters of secondary metabolites. A yellow-golden strain, designated SDU3-1T, and two rose pink strains, designated SDU13 and SDU14T, were isolated from a soil sample. These three strains were aerobic, mesophilic, not salt-tolerant and were able to prey on living microorganisms. SDU13 and SDU14T formed solitary sporangioles under starvation conditions, while SDU3-1T had no fruiting body structures. They showed 95.9-97.0% (SDU3-1T) or 98.7-98.9% (SDU13 and SDU14T) 16S rRNA gene similarity with the type strains of Polyangium, but were phylogenetically separate from them based on the 16S rRNA gene and genome sequences. Their genomes were 12.3 Mbp (SDU3-1T), 13.9 Mbp (SDU13) and 13.8 Mbp (SDU14T) with the G + C content range of 68.3-69.4 mol%. The average nucleotide identity and DNA-DNA hybridization analyses of genomes further indicated that these three strains belonged to two new species in Polyangium. Their major fatty acids were C18:1ω9c, C16:0 and C18:0. The polyphasic taxonomic characterization suggest that the three strains represent two novel species in the genus Polyangium, for which the names Polyangium aurulentum sp. nov. and Polyangium jinanense sp. nov. are proposed, and the type strains are SDU3-1T (=CGMCC 1.16875T = KCTC 72136T) and SDU14T (=CCTCC AB 2021123T = KCTC 82625T), respectively.


Assuntos
Myxococcales , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos , Hibridização de Ácido Nucleico , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo
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