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1.
Sci Rep ; 14(1): 12823, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834839

RESUMO

The prevalence of cardiovascular disease (CVD) has surged in recent years, making it the foremost cause of mortality among humans. The Electrocardiogram (ECG), being one of the pivotal diagnostic tools for cardiovascular diseases, is increasingly gaining prominence in the field of machine learning. However, prevailing neural network models frequently disregard the spatial dimension features inherent in ECG signals. In this paper, we propose an ECG autoencoder network architecture incorporating low-rank attention (LRA-autoencoder). It is designed to capture potential spatial features of ECG signals by interpreting the signals from a spatial perspective and extracting correlations between different signal points. Additionally, the low-rank attention block (LRA-block) obtains spatial features of electrocardiogram signals through singular value decomposition, and then assigns these spatial features as weights to the electrocardiogram signals, thereby enhancing the differentiation of features among different categories. Finally, we utilize the ResNet-18 network classifier to assess the performance of the LRA-autoencoder on both the MIT-BIH Arrhythmia and PhysioNet Challenge 2017 datasets. The experimental results reveal that the proposed method demonstrates superior classification performance. The mean accuracy on the MIT-BIH Arrhythmia dataset is as high as 0.997, and the mean accuracy and F 1 -score on the PhysioNet Challenge 2017 dataset are 0.850 and 0.843.


Assuntos
Eletrocardiografia , Redes Neurais de Computação , Eletrocardiografia/métodos , Humanos , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Aprendizado de Máquina , Processamento de Sinais Assistido por Computador , Algoritmos , Doenças Cardiovasculares/diagnóstico
2.
Food Chem ; 446: 138805, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38422639

RESUMO

Non-specific binding in fluorescence resonance energy transfer (FRET) remains a challenge in foodborne pathogen detection, resulting in interference of high background signals. Herein, we innovatively reported a dual-mode FRET sensor based on a "noise purifier" for the ultrasensitive quantification of Escherichia coli O157:H7 in food. An efficient FRET system was constructed with polymyxin B-modified nitrogen-sulfur co-doped graphene quantum dots (N, S-GQDs@PMB) as donors and aptamer-modified yellow carbon dots (Y-CDs@Apt) as acceptors. Magnetic multi-walled carbon nanotubes (Fe@MWCNTs) were employed as a "noise purifier" to reduce the interference of the fluorescence background. Under the background purification mode, the sensitivity of the dual-mode signals of the FRET sensor has increased by an order of magnitude. Additionally, smartphone-assisted colorimetric analysis enabled point-of-care detection of E. coli O157:H7 in real samples. The developed sensing platform based on a "noise purifier" provides a promising method for ultrasensitive on-site testing of trace pathogenic bacteria in various foodstuffs.


Assuntos
Nanotubos de Carbono , Pontos Quânticos , Fluorescência , Smartphone , Escherichia coli , Pontos Quânticos/química , Testes Imediatos
3.
Animals (Basel) ; 14(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38200905

RESUMO

Wuzhishan (WZS) pigs, which are minipigs native to Hainan Province in China, are characterized by strong resistance to extreme hot temperatures and humidity. The relationship between their immune response and growth still needs to be clarified. In this study, we used whole genome sequencing (WGS) to detect variations within 37 WZS pigs, 32 Large White (LW) pigs, and 22 Xiangxi black (XXB) pigs, and ~2.49 GB of SNPs were obtained. These data were combined with those of two other pig breeds, and it was found that most of the genes detected (354) were located within the distinct genetic regions between WZS pigs and LW pigs. The network that was constructed using these genes represented a center including 12 hub genes, five of which had structural variations (SVs) within their regulatory regions. Furthermore, RNA-seq and RT-qPCR data for 12 genes were primarily consistent in liver, spleen, and LDM tissues. Notably, the expression of HSPs (HSPD1 and HSPE1) was higher while that of most genes involved in the JAK3-STAT pathway were lower in liver tissue of WZS pigs, compared with LW pigs. This likely not only reduced inflammation-related immune response but also impaired their growth. Our findings demonstrated the role of HSPs in the connection between inflammation and growth rate, while also providing the fundamental genetic selection of the adaptability of WZS pigs.

4.
Food Microbiol ; 119: 104455, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225055

RESUMO

Cronobacter (seven species) can survive in dry powdered infant formula for a long time, but the thorough molecular mechanism of resistance to desiccation remains elusive. Here we examine the regulation mechanism of Cronobacter's tolerance to desiccation by the typical two-component system (TCS) EnvZ/OmpR. When exposed to desiccation conditions, Cronobacter showed higher survival than other pathogens, as well as significantly up-regulated expression of ompR and otsAB genes with markedly decreased survival of their mutants, suggesting their relationship with desiccation tolerance. OmpR directly binds to the promoter of trehalose biosynthesis operon otsBA, significantly enhancing their expression, and boosting the trehalose levels. The ompR-deletion in other six species further confirmed its positive regulation in desiccation tolerance. Our data present a hypothesis that EnvZ/OmpR increases intracellular trehalose levels against damage to the cells, which prompts Cronobacter to survive in desiccation conditions. This study reveals a universal molecular mechanism for desiccation resistance in Cronobacter species.


Assuntos
Cronobacter , Humanos , Lactente , Cronobacter/genética , Trealose , Dessecação , Regiões Promotoras Genéticas , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo
5.
Biosens Bioelectron ; 248: 115991, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38169279

RESUMO

The effective combination of ultra-precise detection and on-demand sterilization stands out as one of the most valuable antifouling methods to combat pathogenic bacteria source and ensure the environment and food safety. Herein, an innovative "five birds one stone" aptasensor has been reported. It integrates magnetic separation, tri-modal precision detection, and efficient sterilization for monitoring of Staphylococcus aureus. Firstly, as a switch of the aptasensor, aptamer-modified potassium chloride-doped carbon dots (apt/KCl@CDs) could be adsorbed onto the surface of magnetic multi-walled carbon nanotube composites (M-MWCNTs) through π-π stacking, which could be replaced by the specific binding of the target bacteria to the aptamer. The mutual interference between the nanomaterials could be eliminated by this reverse magnetosorption strategy, enhancing the test sensitivity. In addition to the fluorescence properties, the peroxidase activity possessed by apt/KCl@CDs enables the conversion of the (3,3',5,5'-tetramethylbenzidine) TMB-H2O2 colorimetric system to a photothermal modal. Then, the ultra-precision detection in the assay was achieved by the fluorescence-colorimetric-photothermal tri-modal sensing from the formation of S. aureus-apt/KCl@CDs in the supernatant. Besides, the efficient sterilization could be ensured by adsorbing the apt/KCl@CDs on the surface of S. aureus, generating toxic •OH for direct attacking cells. This was the first report that was more beneficial for bacterial eradication. The detection limits of fluorescence, colorimetric and photothermal modals were 4.81 cfu/mL, 3.40 cfu/mL and 6.74 cfu/mL, respectively. The magnetic nanoplatform integrating tri-modal detection-sterilization meets the demand for highly sensitive and precise detection in different scenarios, providing immediate control for pathogens and broad application prospects.


Assuntos
Anti-Infecciosos , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Staphylococcus aureus/química , Peróxido de Hidrogênio , Técnicas Biossensoriais/métodos , Bactérias , Fenômenos Magnéticos , Limite de Detecção , Aptâmeros de Nucleotídeos/química
6.
J Am Coll Surg ; 238(4): 436-447, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38214445

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR) T cells targeting the B-cell antigen CD19 are standard therapy for relapsed or refractory B-cell lymphoma and leukemia. CAR T cell therapy in solid tumors is limited due to an immunosuppressive tumor microenvironment and a lack of tumor-restricted antigens. We recently engineered an oncolytic virus (CF33) with high solid tumor affinity and specificity to deliver a nonsignaling truncated CD19 antigen (CD19t), allowing targeting by CD19-CAR T cells. Here, we tested this combination against pancreatic cancer. STUDY DESIGN: We engineered CF33 to express a CD19t (CF33-CD19t) target. Flow cytometry and ELISA were performed to quantify CD19t expression, immune activation, and killing by virus and CD19-CAR T cells against various pancreatic tumor cells. Subcutaneous pancreatic human xenograft tumor models were treated with virus, CAR T cells, or virus+CAR T cells. RESULTS: In vitro, CF33-CD19t infection of tumor cells resulted in >90% CD19t cell-surface expression. Coculturing CD19-CAR T cells with infected cells resulted in interleukin-2 and interferon gamma secretion, upregulation of T-cell activation markers, and synergistic cell killing. Combination therapy of virus+CAR T cells caused significant tumor regression (day 13): control (n = 16, 485 ± 20 mm 3 ), virus alone (n = 20, 254 ± 23 mm 3 , p = 0.0001), CAR T cells alone (n = 18, 466 ± 25 mm 3 , p = NS), and virus+CAR T cells (n = 16, 128 ± 14 mm 3 , p < 0.0001 vs control; p = 0.0003 vs virus). CONCLUSIONS: Engineered CF33-CD19t effectively infects and expresses CD19t in pancreatic tumors, triggering cell killing and increased immunogenic response by CD19-CAR T cells. Notably, CF33-CD19t can turn cold immunologic tumors hot, enabling solid tumors to be targetable by agents designed against liquid tumor antigens.


Assuntos
Vírus Oncolíticos , Neoplasias Pancreáticas , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Vírus Oncolíticos/genética , Vírus Oncolíticos/metabolismo , Linfócitos T/metabolismo , Linfócitos T/transplante , Antígenos CD19/metabolismo , Neoplasias Pancreáticas/terapia , Microambiente Tumoral
7.
BMC Genom Data ; 24(1): 77, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097986

RESUMO

BACKGROUND: Goat products have played a crucial role in meeting the dietary demands of people since the Neolithic era, giving rise to a multitude of goat breeds globally with varying characteristics and meat qualities. The primary objective of this study is to pinpoint the pivotal genes and their functions responsible for regulating muscle fiber growth in the longissimus dorsi muscle (LDM) through DNA methylation modifications in Hainan black goats and hybrid goats. METHODS: Whole-genome bisulfite sequencing (WGBS) was employed to scrutinize the impact of methylation on LDM growth. This was accomplished by comparing methylation differences, gene expression, and their associations with growth-related traits. RESULTS: In this study, we identified a total of 3,269 genes from differentially methylated regions (DMR), and detected 189 differentially expressed genes (DEGs) through RNA-seq analysis. Hypo DMR genes were primarily enriched in KEGG terms associated with muscle development, such as MAPK and PI3K-Akt signaling pathways. We selected 11 hub genes from the network that intersected the gene sets within DMR and DEGs, and nine genes exhibited significant correlation with one or more of the three LDM growth traits, namely area, height, and weight of loin eye muscle. Particularly, PRKG1 demonstrated a negative correlation with all three traits. The top five most crucial genes played vital roles in muscle fiber growth: FOXO3 safeguarded the myofiber's immune environment, FOXO6 was involved in myotube development and differentiation, and PRKG1 facilitated vasodilatation to release more glucose. This, in turn, accelerated the transfer of glucose from blood vessels to myofibers, regulated by ADCY5 and AKT2, ultimately ensuring glycogen storage and energy provision in muscle fibers. CONCLUSION: This study delved into the diverse methylation modifications affecting critical genes, which collectively contribute to the maintenance of glycogen storage around myofibers, ultimately supporting muscle fiber growth.


Assuntos
Cabras , Fosfatidilinositol 3-Quinases , Animais , Humanos , Cabras/genética , Fibras Musculares Esqueléticas , Glucose , Glicogênio , Fatores de Transcrição Forkhead
8.
Food Res Int ; 172: 113143, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689845

RESUMO

Cronobacter malonaticus (C. malonaticus) is a food-borne pathogen inducing severe infections both in infants and adults, and it could survive in dry powdered infant formula (PIF) for a long time, implying its strong tolerance to desiccation. However, the thorough molecular mechanism of resistance to desiccation remains elusive. When C. malonaticus was exposed to desiccation conditions (7, 15, and 30 d), transcriptomic analysis provided a universal adaptation strategy to withstand desiccation with the increased compatible solutes accumulation, activated stress resistance-related regulators, suppressed protein export and bacterial secretion system, and reduced other unessential survival functions including adhesion, invasion, virulence, and flagellar motility. Importantly, type VI secretion system (T6SS) genes exhibited significantly downregulated expressions, as well as markedly increased survival and viability of their mutants after desiccation treatment, revealing the negative regulation of T6SS in desiccation tolerance. Meanwhile, the decreased expressions of T6SS structure genes in other six species further confirmed the vital role of T6SS in desiccation tolerance of Cronobacter spp. Thus, our studies present a novel hypothesis of desiccation resistance in Cronobacter based on type VI secretion system inhibition, causing the reduction of macromolecule secretion such as effectors and hyperosmolality development within the cytomembrane, which allow Cronobacter to survive in desiccation.


Assuntos
Cronobacter , Sistemas de Secreção Tipo VI , Adulto , Lactente , Humanos , Dessecação , Transcriptoma , Cronobacter/genética , Fórmulas Infantis
9.
Front Microbiol ; 14: 1292870, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38352062

RESUMO

The chemical engineering of natural extracts has emerged as an effective strategy for the production of diverse libraries of chemicals, making it integral to drug discovery. A chemical engineering strategy based on the epoxidation and ring-opening reactions was used to prepare diversity-enhanced extracts of Chaetomium madrasense 375. Eleven unnatural cytochalasan derivatives (1-11) with unique functional groups, such as amine and isoxazole, were isolated and characterized from these chemically engineered extracts of C. madrasense 375. The identification of these new structures was accomplished through comprehensive spectroscopic analysis, supplemented by synthetic considerations. Notably, compounds 5 and 13-16 displayed potent phytotoxic effects on Arabidopsis thaliana, while compounds 1, 2, 5, 10, and 12 demonstrated inhibitory activities on LPS-induced NO production in RAW264.7 cells. Among them, compound 1 was found to be able to inhibit the upregulated expression of the inducible nitric oxide synthase (iNOS) protein induced by LPS, while also decreasing the production of pro-inflammatory cytokines (IL-6) and influencing the phosphorylation of p38, ERK1/2, and JNK at 100 µM. Our findings demonstrate that the chemical engineering of natural product extracts can be an efficient technique for the generation of novel bioactive molecules.

10.
Radiology ; 305(2): 410-418, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35819327

RESUMO

Background Recent evidence suggests that presence of an intracranial arterial thrombus with a hyperdense artery sign (HAS) at noncontrast CT (NCCT) is associated with better response to intravenous alteplase. Patients with HAS may benefit more from combined intravenous alteplase and endovascular treatment (EVT). Purpose To investigate whether HAS at NCCT modifies the treatment effect of adding intravenous alteplase on clinical outcome in patients with acute large-vessel occlusion undergoing EVT. Materials and Methods This study is a secondary analysis of a prospective randomized trial (Direct Intra-arterial thrombectomy in order to Revascularize AIS patients with large-vessel occlusion Efficiently in Chinese Tertiary hospitals: A Multicenter randomized clinical Trial [DIRECT-MT]), which compared adding alteplase to EVT versus EVT alone in participants with acute large-vessel occlusion between February 2018 and July 2019. Participants with catheter angiograms and adequate NCCT for HAS evaluation were included. HAS was determined visually by two independent investigators at baseline NCCT. Treatment effect of intravenous alteplase administration according to presence of HAS on the primary clinical outcome (modified Rankin Scale [mRS] score at 90 days) and secondary and safety outcomes were assessed using adjusted multivariable regression models. Results Among 633 included participants (356 men [56%]; median age, 69 years), HAS was observed in 283 participants (45%): 142 of 313 participants (45%) in the EVT-only group and 141 of 320 participants (44%) in the group with added intravenous alteplase. Treatment-by-HAS interaction was observed for the primary outcome (P < .001), whereby a shift in favor of better outcomes with added intravenous alteplase occurred in participants with HAS (adjusted odds ratio [OR]: 1.82; 95% CI: 1.18, 2.79), while an adverse effect was seen in participants without HAS (adjusted OR: 0.62; 95% CI: 0.42, 0.91). This also held true for three secondary outcomes (excellent outcome [mRS score of 0-1 at 90 days], P = .005; good outcome [mRS score of 0-2 at 90 days], P = .008; final successful reperfusion, P = .04) in the adjusted models. Conclusion After acute ischemic stroke, presence of hyperdense artery sign (HAS) at baseline noncontrast CT indicated better outcomes when alteplase was added to endovascular treatment, but adding alteplase to endovascular treatment resulted in worse outcomes in participants without HAS. Clinical trial registration no. NCT03469206 © RSNA, 2022 Online supplemental material is available for this article.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Humanos , Masculino , Artérias , Isquemia Encefálica/etiologia , Procedimentos Endovasculares/métodos , Fibrinolíticos/uso terapêutico , Fibrinolíticos/efeitos adversos , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Ativador de Plasminogênio Tecidual/uso terapêutico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Feminino
11.
ACS Biomater Sci Eng ; 8(7): 3107-3121, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35678715

RESUMO

In tumors, the metabolic demand of cancer cells often outpaces oxygen supply, resulting in a gradient of tumor hypoxia accompanied with heterogeneous resistance to cancer therapeutics. Models recapitulating tumor hypoxia are therefore essential for developing more effective cancer therapeutics. Existing in vitro models often fail to capture the spatial heterogeneity of tumor hypoxia or involve high-cost, complex fabrication/handling techniques. Here, we designed a highly tunable microfluidic device that induces hypoxia through natural cell metabolism and oxygen diffusion barriers. We adopted a cleanroom-free, micromilling-replica-molding strategy and a microfluidic liquid-pinning approach to streamline the fabrication and tumor model establishment. We also implemented a thin-film oxygen diffusion barrier design, which was optimized through COMSOL simulation, to support both two-dimensional (2-D) and three-dimensional (3-D) hypoxic models. We demonstrated that liquid-pinning enables an easy, injection-based micropatterning of cancer cells of a wide range of parameters, showing the high tunability of our design. Human breast cancer and prostate cancer cells were seeded and stained after 24 h of 2-D and 3-D culture to validate the natural induction of hypoxia. We further demonstrated the feasibility of the parallel microfluidic channel design to evaluate dual therapeutic conditions in the same device. Overall, our new microfluidic tumor model serves as a user-friendly, cost-effective, and highly scalable platform that provides spatiotemporal analysis of the hypoxic tumor microenvironments suitable for high-content biological studies and therapeutic discoveries.


Assuntos
Neoplasias da Mama , Técnicas Analíticas Microfluídicas , Humanos , Hipóxia , Masculino , Técnicas Analíticas Microfluídicas/métodos , Microfluídica , Oxigênio/metabolismo , Hipóxia Tumoral , Microambiente Tumoral
12.
Front Microbiol ; 12: 689855, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248914

RESUMO

An effective solution to global human zinc (Zn) deficiency is Zn biofortification of staple food crops, which has been hindered by the low available Zn in calcareous soils worldwide. Many culturable soil microbes have been reported to increase Zn availability in the laboratory, while the status of these microbes in fields and whether there are unculturable Zn-mobilizing microbes remain unexplored. Here, we use the culture-independent metagenomic sequencing to investigate the rhizosphere microbiome of three high-Zn (HZn) and three low-Zn (LZn) wheat cultivars in a field experiment with calcareous soils. The average grain Zn concentration of HZn was higher than the Zn biofortification target 40 mg kg-1, while that of LZn was lower than 40 mg kg-1. Metagenomic sequencing and analysis showed large microbiome difference between wheat rhizosphere and bulk soil but small difference between HZn and LZn. Most of the rhizosphere-enriched microbes in HZn and LZn were in common, including many of the previously reported soil Zn-mobilizing microbes. Notably, 30 of the 32 rhizosphere-enriched species exhibiting different abundances between HZn and LZn possess the functional genes involved in soil Zn mobilization, especially the synthesis and exudation of organic acids and siderophores. Most of the abundant potential Zn-mobilizing species were positively correlated with grain Zn concentration and formed a module with strong interspecies relations in the co-occurrence network of abundant rhizosphere-enriched microbes. The potential Zn-mobilizing species, especially Massilia and Pseudomonas, may contribute to the cultivars' variation in grain Zn concentration, and they deserve further investigation in future studies on Zn biofortification.

13.
Front Chem ; 9: 620589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968893

RESUMO

"Diversity-enhanced extracts" is an effective method of producing chemical libraries for the purpose of drug discovery. Three rare new cytochalasan derivative chaetoglobosins B1-B3 (1-3) were obtained from chemically engineered crude broth extracts of Chaetomium madrasense 375 prepared by reacting with hydrazine monohydrate and four known metabolite chaetoglobosins (4-7) were also identified from the fungus. The structures were identified by NMR and MS analysis and electronic circular dichroism simulation. In addition, the antiproliferative activities of these compounds were also evaluated, and the drug-resistant activities of cytochalasans were evaluated for the first time. Compound 6 possessed potent activity against four human cancer cells (A549, HCC827, SW620, and MDA-MB-231), and two drug-resistant HCC827 cells (Gefitinib-resistant, Osimertinib-resistant) compared with the positive controls.

14.
J Dairy Sci ; 104(8): 8517-8529, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33896635

RESUMO

Escherichia coli O157:H7 (E. coli O157:H7), one of the most widespread foodborne pathogens, can cause a series of diseases and even lead to death. In this study, a highly sensitive method was developed by combining aptamer-exonuclease III (Exo III)-assisted amplification with lateral flow assay (LFA) based on gold nanoparticles (AuNP). The compound of single-stranded (ss) DNA-anti-E. coli O157:H7 aptamer (ssDNA-aptamer) was formed by hybridization between designed target ssDNA and aptamer. When E. coli O157:H7 was present, target bacteria were bound with the aptamer, and the free target ssDNA was hybridized with the probes of the designed hairpin (HP) structure. Exo III digests the 3' double-stranded blunt end of the complex and releases the enzyme product. Because the remaining sequence of the HP of the designed enzyme product was the same as the target ssDNA sequence, the target ssDNA could be amplified. Finally, the enhanced target ssDNA was combined with AuNP-LFA to achieve visual detection of E. coli O157:H7. The quantitative ability of this platform for E. coli O157:H7 was 7.6 × 101 cfu/mL in pure culture, and the detection limit in milk was 8.35 × 102 cfu/mL. This LFA was highly specific to E. coli O157:H7, and the time for detection of E. coli O157:H7 in milk was 4 h. Hence, this system has important application prospects in the detection of pathogenic bacteria in dairy products.


Assuntos
Escherichia coli O157 , Nanopartículas Metálicas , Animais , Exodesoxirribonucleases , Microbiologia de Alimentos , Ouro , Leite
15.
Gigascience ; 10(1)2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33506264

RESUMO

BACKGROUND: Biogas production with anaerobic digestion (AD) is one of the most promising solutions for both renewable energy production and resolving the environmental problem caused by the worldwide increase in organic waste. However, the complex structure of the microbiome in AD is poorly understood. FINDINGS: In this study, we constructed a microbial gene catalog of AD (22,840,185 genes) based on 1,817 Gb metagenomic data derived from digestate samples of 56 full-scale biogas plants fed with diverse feedstocks. Among the gene catalog, 73.63% and 2.32% of genes were taxonomically annotated to Bacteria and Archaea, respectively, and 57.07% of genes were functionally annotated with KEGG orthologous groups. Our results confirmed the existence of core microbiome in AD and showed that the type of feedstock (cattle, chicken, and pig manure) has a great influence on carbohydrate hydrolysis and methanogenesis. In addition, 2,426 metagenome-assembled genomes were recovered from all digestate samples, and all genomes were estimated to be ≥80% complete with ≤10% contamination. CONCLUSIONS: This study deepens our understanding of the microbial composition and function in the AD process and also provides a huge number of reference genome and gene resources for analysis of anaerobic microbiota.


Assuntos
Biocombustíveis , Reatores Biológicos , Anaerobiose , Animais , Bovinos , Genes Microbianos , Esterco , Suínos
16.
Mol Ecol Resour ; 21(1): 287-300, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32939994

RESUMO

Apolygus lucorum (Miridae) is an omnivorous pest that occurs worldwide and is notorious for the serious damage it causes to various crops and substantial economic losses. Although some studies have examined the biological characteristics of the mirid bug, no reference genome is available in Miridae, limiting in-depth studies of this pest. Here, we present a chromosome-scale reference genome of A. lucorum, the first sequenced Miridae species. The assembled genome size was 1.02 Gb with a contig N50 of 785 kb. With Hi-C scaffolding, 1,016 Mb contig sequences were clustered, ordered and assembled into 17 large scaffolds with scaffold N50 length 68 Mb, each corresponding to a natural chromosome. Numerous transposable elements occur in this genome and contribute to the large genome size. Expansions of genes associated with omnivorousness and mesophyll feeding such as those related to digestion, chemosensory perception, and detoxification were observed in A. lucorum, suggesting that gene expansion contributed to its strong environmental adaptability and severe harm to crops. We clarified that a salivary enzyme polygalacturonase is unique in mirid bugs and has significantly expanded in A. lucorum, which may contribute to leaf damage from this pest. The reference genome of A. lucorum not only facilitates biological studies of Hemiptera as well as an understanding of the damage mechanism of mesophyll feeding, but also provides a basis on which to develop efficient control technologies for mirid bugs.


Assuntos
Genoma de Inseto , Herbivoria , Heterópteros , Animais , Produtos Agrícolas , Elementos de DNA Transponíveis , Heterópteros/genética , Poligalacturonase , Saliva/enzimologia
17.
Mol Ecol Resour ; 21(2): 478-494, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33000522

RESUMO

Whole-genome duplication (WGD), contributing to evolutionary diversity and environmental adaptability, has been observed across a wide variety of eukaryotic groups, but not in molluscs. Molluscs are the second largest animal phylum in terms of species numbers, and among the organisms that have successfully adapted to the nonmarine realm through aquatic-terrestrial (A-T) transition. We assembled a chromosome-level reference genome for Achatina immaculata, a globally invasive species, and compared the genomes of two giant African snails (A. immaculata and Achatina fulica) to other available mollusc genomes. Macrosynteny, colinearity blocks, Ks peak and Hox gene clusters collectively suggested a WGD event in the two snails. The estimated WGD timing (~70 million years ago) was close to the speciation age of the Sigmurethra-Orthurethra (within Stylommatophora) lineage and the Cretaceous-Tertiary (K-T) mass extinction, indicating that the WGD may have been a common event shared by all Sigmurethra-Orthurethra species and conferred ecological adaptability allowing survival after the K-T extinction event. Furthermore, the adaptive mechanism of WGD in terrestrial ecosystems was confirmed by the presence of gene families related to the respiration, aestivation and immune defence. Several mucus-related gene families expanded early in the Stylommatophora lineage, and the haemocyanin and phosphoenolpyruvate carboxykinase families doubled during WGD, and zinc metalloproteinase genes were highly tandemly duplicated after WGD. This evidence suggests that although WGD may not have been the direct driver of the A-T transition, it played an important part in the terrestrial adaptation of giant African snails.


Assuntos
Evolução Biológica , Ecossistema , Duplicação Gênica , Caramujos/genética , Animais , Genoma , Filogenia , Caramujos/classificação
18.
Front Microbiol ; 11: 1462, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733410

RESUMO

Mikania micrantha is a noxious invasive plant causing enormous economic losses and ecological damage. Soil microbiome plays an important role in the invasion process of M. micrantha, while little is known about its rhizosphere microbiome composition and function. In this study, we identified the distinct rhizosphere microbial communities of M. micrantha, by comparing them with those of two coexisting native plants (Polygonum chinense and Paederia scandens) and the bulk soils, using metagenomics data from field sampling and pot experiment. As a result, the enrichment of phosphorus-solubilizing bacteria Pseudomonas and Enterobacter was consistent with the increased soil available phosphorus in M. micrantha rhizosphere. Furthermore, the pathogens of Fusarium oxysporum and Ralstonia solanacearum and pathogenic genes of type III secretion system (T3SS) were observed to be less abundant in M. micrantha rhizosphere, which might be attributed to the enrichment of biocontrol bacteria Catenulispora, Pseudomonas, and Candidatus Entotheonella and polyketide synthase (PKS) genes involved in synthesizing antibiotics and polyketides to inhibit pathogens. These findings collectively suggested that the enrichment of microbes involved in nutrient acquisition and pathogen suppression in the rhizosphere of M. micrantha largely enhances its adaptation and invasion to various environments.

19.
Nat Commun ; 11(1): 340, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953413

RESUMO

Mikania micrantha is one of the top 100 worst invasive species that can cause serious damage to natural ecosystems and substantial economic losses. Here, we present its 1.79 Gb chromosome-scale reference genome. Half of the genome is composed of long terminal repeat retrotransposons, 80% of which have been derived from a significant expansion in the past one million years. We identify a whole genome duplication event and recent segmental duplications, which may be responsible for its rapid environmental adaptation. Additionally, we show that M. micrantha achieves higher photosynthetic capacity by CO2 absorption at night to supplement the carbon fixation during the day, as well as enhanced stem photosynthesis efficiency. Furthermore, the metabolites of M. micrantha can increase the availability of nitrogen by enriching the microbes that participate in nitrogen cycling pathways. These findings collectively provide insights into the rapid growth and invasive adaptation.


Assuntos
Genoma de Planta , Mikania/crescimento & desenvolvimento , Mikania/genética , Mikania/fisiologia , Vias Biossintéticas/genética , Vias Biossintéticas/fisiologia , Ciclo do Carbono , Dióxido de Carbono/metabolismo , Cromossomos de Plantas , Ecologia , Ecossistema , Evolução Molecular , Genômica , Espécies Introduzidas , Nitrogênio/metabolismo , Ciclo do Nitrogênio , Fotossíntese/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Análise de Sequência de DNA , Transcriptoma
20.
Microbiome ; 6(1): 211, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30482240

RESUMO

BACKGROUND: Sub-therapeutic antibiotics are widely used as growth promoters in the poultry industry; however, the resulting antibiotic resistance threatens public health. A plant-derived growth promoter, Macleaya cordata extract (MCE), with effective ingredients of benzylisoquinoline alkaloids, is a potential alternative to antibiotic growth promoters. Altered intestinal microbiota play important roles in growth promotion, but the underlying mechanism remains unknown. RESULTS: We generated 1.64 terabases of metagenomic data from 495 chicken intestinal digesta samples and constructed a comprehensive chicken gut microbial gene catalog (9.04 million genes), which is also the first gene catalog of an animal's gut microbiome that covers all intestinal compartments. Then, we identified the distinctive characteristics and temporal changes in the foregut and hindgut microbiota. Next, we assessed the impact of MCE on chickens and gut microbiota. Chickens fed with MCE had improved growth performance, and major microbial changes were confined to the foregut, with the predominant role of Lactobacillus being enhanced, and the amino acids, vitamins, and secondary bile acids biosynthesis pathways being upregulated, but lacked the accumulation of antibiotic-resistance genes. In comparison, treatment with chlortetracycline similarly enriched some biosynthesis pathways of nutrients in the foregut microbiota, but elicited an increase in antibiotic-producing bacteria and antibiotic-resistance genes. CONCLUSION: The reference gene catalog of the chicken gut microbiome is an important supplement to animal gut metagenomes. Metagenomic analysis provides insights into the growth-promoting mechanism of MCE, and underscored the importance of utilizing safe and effective growth promoters.


Assuntos
Benzilisoquinolinas/farmacologia , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Substâncias de Crescimento/farmacologia , Lactobacillus/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Animais , Microbioma Gastrointestinal/genética , Probióticos/farmacologia , Ranunculales/química
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