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1.
Nature ; 632(8027): 1124-1130, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39048829

RESUMO

Methanogenic archaea are main contributors to methane emissions, and have a crucial role in carbon cycling and global warming. Until recently, methanogens were confined to Euryarchaeota, but metagenomic studies revealed the presence of genes encoding the methyl coenzyme M reductase complex in other archaeal clades1-4, thereby opening up the premise that methanogenesis is taxonomically more widespread. Nevertheless, laboratory cultivation of these non-euryarchaeal methanogens was lacking to corroborate their potential methanogenic ability and physiology. Here we report the isolation of a thermophilic archaeon LWZ-6 from an oil field. This archaeon belongs to the class Methanosuratincolia (originally affiliated with 'Candidatus Verstraetearchaeota') in the phylum Thermoproteota. Methanosuratincola petrocarbonis LWZ-6 is a strict hydrogen-dependent methylotrophic methanogen. Although previous metagenomic studies speculated on the fermentative potential of Methanosuratincolia members, strain LWZ-6 does not ferment sugars, peptides or amino acids. Its energy metabolism is linked only to methanogenesis, with methanol and monomethylamine as electron acceptors and hydrogen as an electron donor. Comparative (meta)genome analysis confirmed that hydrogen-dependent methylotrophic methanogenesis is a widespread trait among Methanosuratincolia. Our findings confirm that the diversity of methanogens expands beyond the classical Euryarchaeota and imply the importance of hydrogen-dependent methylotrophic methanogenesis in global methane emissions and carbon cycle.


Assuntos
Archaea , Euryarchaeota , Metano , Archaea/metabolismo , Archaea/genética , Archaea/classificação , Archaea/isolamento & purificação , Metabolismo Energético , Euryarchaeota/classificação , Euryarchaeota/metabolismo , Genoma Arqueal , Hidrogênio/metabolismo , Metano/biossíntese , Metano/metabolismo , Metanol/metabolismo , Campos de Petróleo e Gás/microbiologia , Oxirredução , Oxirredutases/metabolismo , Oxirredutases/genética , Filogenia , Ciclo do Carbono
3.
Plant Cell Environ ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39262218

RESUMO

Nicotiana benthamiana, a widely acknowledged laboratory model plant for molecular studies, exhibits lethality to certain insect pests and can serve as a dead-end trap plant for pest control in the field. However, the underlying mechanism of N. benthamiana's resistance against insects remains unknown. Here, we elucidate that the lethal effect of N. benthamiana on the whitefly Bemisia tabaci arises from the toxic glandular trichome exudates. By comparing the metabolite profiles of trichome exudates, we found that 51 metabolites, including five O-acyl sugars (O-AS) with medium-chain acyl moieties, were highly accumulated in N. benthamiana. Silencing of two O-AS biosynthesis genes, branched-chain keto acid dehydrogenase (BCKD) and Isopropyl malate synthase-C (IPMS-C), significantly reduced the O-AS levels in N. benthamiana and its resistance against whiteflies. Additionally, we demonstrated that the higher expression levels of BCKD and IPMS-C in the trichomes of N. benthamiana contribute to O-AS synthesis and consequently enhance whitefly resistance. Furthermore, overexpression of NbBCKD and NbIPMS-C genes in the cultivated tobacco Nicotiana tabacum enhanced its resistance to whiteflies. Our study revealed the metabolic and molecular mechanisms underlying the lethal effect of N. benthamiana on whiteflies and presents a promising avenue for improving whitefly resistance.

4.
Oral Dis ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720551

RESUMO

OBJECTIVE: Our previous studies have found that the composition ratio of Prevotella melaninogenica (Pm) on buccal mucosa surface of oral lichen planus (OLP) patients increased significantly compared with control. Furthermore, Pm could invade the epithelium of OLP patients. This study aimed to further explore the impact of Pm on oral keratinocytes. MATERIALS AND METHODS: The Pm-human oral keratinocyte (HOK) co-culture model was established to detect monolayer permeability, zona occludens-1 (ZO-1) expression, and intracellular survival of Pm. We performed RNA-seq followed by identification of differentially expressed genes (DEGs) and Gene Ontology (GO) analysis, with a particular focus on myosin light chain kinase (MLCK). An MLCK inhibitor ML-7 was utilized in Pm-HOK co-culture model to assess its effects on monolayer permeability and ZO-1 expression. RESULTS: HOK monolayer permeability was increased, and ZO-1 expression was decreased after co-culture (p < 0.05). Pm could survive in HOK cells. RNA-seq revealed MLCK was an upregulated common DEG. The expression of MLCK in the Pm-HOK co-culture model was upregulated. Inhibition of MLCK rescued the increased epithelial permeability, and ZO-1 expression was upregulated (p < 0.05). CONCLUSION: MLCK may be involved in disrupting epithelial barrier function by Pm.

5.
Nucleic Acids Res ; 50(D1): D1238-D1243, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34986599

RESUMO

Literature-described targets of herbal ingredients have been explored to facilitate the mechanistic study of herbs, as well as the new drug discovery. Though several databases provided similar information, the majority of them are limited to literatures before 2010 and need to be updated urgently. HIT 2.0 was here constructed as the latest curated dataset focusing on Herbal Ingredients' Targets covering PubMed literatures 2000-2020. Currently, HIT 2.0 hosts 10 031 compound-target activity pairs with quality indicators between 2208 targets and 1237 ingredients from more than 1250 reputable herbs. The molecular targets cover those genes/proteins being directly/indirectly activated/inhibited, protein binders, and enzymes substrates or products. Also included are those genes regulated under the treatment of individual ingredient. Crosslinks were made to databases of TTD, DrugBank, KEGG, PDB, UniProt, Pfam, NCBI, TCM-ID and others. More importantly, HIT enables automatic Target-mining and My-target curation from daily released PubMed literatures. Thus, users can retrieve and download the latest abstracts containing potential targets for interested compounds, even for those not yet covered in HIT. Further, users can log into 'My-target' system, to curate personal target-profiling on line based on retrieved abstracts. HIT can be accessible at http://hit2.badd-cao.net.


Assuntos
Bases de Dados Factuais , Bases de Dados de Produtos Farmacêuticos , Descoberta de Drogas , Medicamentos de Ervas Chinesas/classificação , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa , Ligação Proteica/efeitos dos fármacos , Proteínas/efeitos dos fármacos
6.
Opt Express ; 31(13): 22144-22156, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381295

RESUMO

Aiming at the problems of narrow working bandwidth, low efficiency, and complex structure of existing terahertz chiral absorption, we propose a chiral metamirror composed of C-shaped metal split ring and L-shaped vanadium dioxide (VO2). This chiral metamirror is composed of three layers of structure, a gold substrate at the bottom, the first polyethylene cyclic olefin copolymer (Topas) dielectric layer and VO2-metal hybrid structure as the top. Our theoretical results led us to show that this chiral metamirror has a circular dichroism (CD) value greater than 0.9 at 5.70 to 8.55 THz and has a maximum value of 0.942 at f = 7.18 THz. In addition, by adjusting the conductivity of VO2, the CD value can be continuously adjustable from 0 to 0.942, which means that the proposed chiral metamirror supports the free switching of the CD response between the on and off states, and the CD modulation depth exceeds 0.99 in the range of 3 to 10 THz. Moreover, we discuss the influence of structural parameters and the change of incident angle on the performance of the metamirror. Finally, we believe that the proposed chiral metamirror has important reference value in the terahertz range for constructing chiral light detectors, CD metamirrors, switchable chiral absorbers and spin-related systems. This work will provide a new idea for improving the terahertz chiral metamirror operating bandwidth and promote the development of terahertz broadband tunable chiral optical devices.

7.
Opt Lett ; 48(19): 5153-5156, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773408

RESUMO

The deep application of chiral metasurfaces requires higher flexibility. Herein, we propose a multidimensional tunable chiral graphene metasurface, which uses coherent control to obtain more than 0.8 circular conversion dichroism (CCD) at 2.4 THz as a transmission structure. Its operating frequency can be changed in the 1.3-2.4 THz range, while the amplitude has almost perfect modulation depth in the range of 0-0.8. The mechanism of differential absorption was analyzed through numerical simulation. The device designed is easy to obtain reverse CCD, which is used for unit layout and proves its advantages in near-field imaging. Our work has broadened the path for the development of chiral metasurfaces towards higher degrees of freedom.

8.
Appl Opt ; 62(23): 6205-6211, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37707089

RESUMO

In this paper, a nested micro-ring refractive index sensor based on a subwavelength grating waveguide and the Vernier effect is proposed. In this scheme, the nested micro-ring structure is combined with a subwavelength grating structure to enhance the contact area between the optical field and the analyte, and the wavelength offset is doubled through the Vernier effect. The proposed sensor can effectively increase sensing sensitivity, taking into account the improvement of the free spectral range. This structure enables the device to reach a sensitivity of 8030 nm/RIU near 1550 nm wavelength in a deionized water environment, with a detection limit of 5.659×10-5 RIU and free spectral range of 41.956 nm. The device suggested in this study has a greater reduced footprint than the conventional micro-ring resonant sensor, measuring just 35µm×25µm. Due to its high integration, high sensitivity, and large free spectral range compared to conventional micro-ring resonant sensors, such structures are of great value in biosensing and environmental monitoring.

9.
Appl Opt ; 62(28): 7346-7353, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855501

RESUMO

Electro-optic modulators are essential devices on silicon photonic chips in modern optical communication networks. This paper presents a compact, low-loss electro-optic modulator. The modulation efficiency is greatly improved by embedding the lower half of the slot waveguide into the buried oxide layer and inserting graphene at the junction. The interaction of graphene with an optical field in a waveguide is studied using the finite element method. The functions of phase modulation and absorption modulation are realized by changing the gate voltage to change the chemical potential of graphene. The semi-embedded slot waveguide optical modulator has a length of 50 µm. After simulation verification, it can be used as an electro-absorption modulator and can achieve a modulation depth of 26.38 dB and an insertion loss of 0.60 dB. When used as an electro-refractive modulator, it can be realized with a linear change of phase from zero to π; the total insertion loss is only 0.59 dB. The modulator has a modulation bandwidth of 79.6 GHz, and the energy consumption as electro-absorption and electro-refraction modulation are 0.51 and 1.92 pj/bit, respectively. Compared with common electro-optic modulators, the electro-optic modulator designed in this paper has a higher modulation effect and also takes into account the advantages of low insertion loss and low energy consumption. This research is helpful for the design of higher-performance optical communication network devices.

10.
J Cell Biochem ; 123(9): 1481-1494, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35894175

RESUMO

The functions of oral mucosa include barrier, sensation, and secretion. The barrier protection function is particularly important, which includes physical barrier and immunological barrier. Few studies have revealed the function of oral mucosa by displaying the map of normal oral mucosal cells from the perspective of single cells. Here, single-cell transcriptome sequencing was used to bring a relatively comprehensive map of the normal oral mucosal cells. In total, 26,398 cells from three cases of normal oral mucosa were analyzed by single-cell RNA-sequencing and 14 distinct cell groups were defined, 7 of which were immune cells. We performed subgroup classification and heterogeneity analysis of epithelial cells, T cells, and macrophagocytes, which found a subpopulation of epithelial cells with high expression of major histocompatibility complex class II molecules, a subpopulation CD8+ GZMK+ T cells, and two kinds of active macrophagocytes. Meanwhile, we identified ligand-receptor pairs among the major cell types to explore the interactions and how they maintain the homeostasis of normal oral mucosa. Based on these results, the epithelial barrier function, immunological barrier function, and potential maintenance function of stromal cells in the oral mucosa were described at the single-cell level, which provides basic data resources for further studies of oral mucosal diseases.


Assuntos
Células Epiteliais , Mucosa Bucal , Mucosa Intestinal/metabolismo , Ligantes , RNA/metabolismo , Análise de Sequência de RNA
11.
Int J Mol Sci ; 23(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35054827

RESUMO

Watermelon (Citrullus lanatus) is an important horticultural crop worldwide, but peel cracking caused by peel hardness severely decreases its quality. Lignification is one of the important functions of class III peroxidase (PRX), and its accumulation in the plant cell wall leads to cell thickening and wood hardening. For in-depth physiological and genetical understanding, we studied the relationship between peel hardness and lignin accumulation and the role of PRXs affecting peel lignin biosynthesis using genome-wide bioinformatics analysis. The obtained results showed that lignin accumulation gradually increased to form the peel stone cell structure, and tissue lignification led to peel hardness. A total of 79 ClPRXs (class III) were identified using bioinformatics analysis, which were widely distributed on 11 chromosomes. The constructed phylogenetics indicated that ClPRXs were divided into seven groups and eleven subclasses, and gene members of each group had highly conserved intron structures. Repeated pattern analysis showed that deletion and replication events occurred during the process of ClPRX amplification. However, in the whole-protein sequence alignment analysis, high homology was not observed, although all contained four conserved functional sites. Repeated pattern analysis showed that deletion and replication events occurred during ClPRXs' amplification process. The prediction of the promoter cis-acting element and qRT-PCR analysis in four tissues (leaf, petiole, stem, and peel) showed different expression patterns for tissue specificity, abiotic stress, and hormone response by providing a genetic basis of the ClPRX gene family involved in a variety of physiological processes in plants. To our knowledge, we for the first time report the key roles of two ClPRXs in watermelon peel lignin synthesis. In conclusion, the extensive data collected in this study can be used for additional functional analysis of ClPRXs in watermelon growth and development and hormone and abiotic stress response.


Assuntos
Citrullus/crescimento & desenvolvimento , Biologia Computacional/métodos , Lignina/biossíntese , Peroxidase/genética , Parede Celular/metabolismo , Mapeamento Cromossômico , Citrullus/genética , Citrullus/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Peroxidase/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas
12.
FASEB J ; 34(3): 4415-4429, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31965641

RESUMO

Although the key role of renal fibrosis in the progression of chronic kidney disease (CKD) is well known, the causes of renal fibrosis are not fully clarified. In this study, interferon regulatory factor 1 (IRF-1), a mammalian transcription factor, was highly expressed in fibrotic kidney of CKD patients. Concordantly, the expression level of IRF-1 was significantly elevated in the kidney of unilateral ureteral obstruction (UUO) and Adriamycin nephropathy (ADR) mice. In tubular epithelial cells, overexpression of IRF-1 could induce profibrotic markers expression, which accompanied by dramatic downregulation of Klotho, an important inhibitor of renal fibrosis. Luciferase reporter analysis and ChIP assay revealed that IRF-1 repressed Klotho expression by downregulation of C/EBP-ß, which regulates Klotho gene transcription via directly binding to its promoter. Further investigation showed that tumor necrosis factor-alpha may be an important inducement for the increase of IRF-1 in tubular epithelial cells after UUO and genetic deletion of IRF-1 attenuated renal fibrosis in UUO mice. Hence, these findings demonstrate that IRF-1 contributes to the pathogenesis of renal fibrosis by downregulation of Klotho, and suppresses IRF-1 may be a potential therapeutic target for CKD.


Assuntos
Glucuronidase/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Rim/metabolismo , Rim/patologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Animais , Western Blotting , Linhagem Celular , Imunoprecipitação da Cromatina , Glucuronidase/genética , Células HEK293 , Humanos , Imunoprecipitação , Fator Regulador 1 de Interferon/genética , Rim/efeitos dos fármacos , Proteínas Klotho , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Fator de Necrose Tumoral alfa/farmacologia , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
13.
Molecules ; 26(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299452

RESUMO

In recent decades, demands for novel insecticides against mosquitoes are soaring, yet candidate chemicals with desirable properties are limited. Kathon is a broad-spectrum isothiazolinone microbicide, but other applications remain uncharacterized. First, we treated larvae of Culex quinquefasciatus and Aedes albopictus, two major mosquito vectors of human viral diseases, with Kathon at 15 mg/L (a concentration considered safe in cosmetic and body care products), and at lower concentrations, and found that Kathon treatment resulted in high mortality of larvae. Second, sublethal concentration of Kathon can cause significantly prolonged larval development of C. quinquefasciatus. Third, we explored the effects of two constituents of Kathon, chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT), on the survival of larvae, and found that CMIT was the major toxic component. Further, we explored the mechanisms of action of Kathon against insect cells and found that Kathon reduces cell viability and adenosine triphosphate production but promotes the release of lactate dehydrogenase in Drosophila melanogaster S2 cells. Our results indicate that Kathon is highly toxic to mosquito larvae, and we highlight its potential in the development of new larvicides for mosquito control.


Assuntos
Culicidae/efeitos dos fármacos , Tiazóis/química , Tiazóis/farmacologia , Aedes/efeitos dos fármacos , Animais , Anopheles/efeitos dos fármacos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Culex/efeitos dos fármacos , Culicidae/metabolismo , Inseticidas/química , Larva/efeitos dos fármacos , Controle de Mosquitos/métodos , Mosquitos Vetores
14.
Mol Ther ; 27(5): 1051-1065, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30853453

RESUMO

Renal fibrosis is the main pathological characteristic of chronic kidney disease (CKD), whereas the underlying mechanisms of renal fibrosis are not clear yet. Herein, we found an increased expression of microRNA-34a (miR-34a) in renal tubular epithelial cells of patients with renal fibrosis and mice undergoing unilateral ureteral obstruction (UUO). In miR-34a-/- mice, miR-34a deficiency attenuated the progression of renal fibrosis following UUO surgery. The miR-34a overexpression promoted epithelial-to-mesenchymal transition (EMT) in cultured human renal tubular epithelial HK-2 cells, which was accompanied by sharp downregulation of Klotho, an endogenous inhibitor of renal fibrosis. Luciferase reporter assay revealed that miR-34a downregulated Klotho expression though direct binding with the 3' UTR of Klotho. Conversely, overexpression of Klotho prevented miR-34a-induced EMT in HK-2 cells. Furthermore, results showed that miR-34a was induced by transforming growth factor ß1 (TGF-ß1) through p53 activation, whereas dihydromyricetin could inhibit TGF-ß1-induced miR-34a overexpression. Accordingly, dihydromyricetin administration dramatically restored the aberrant upregulation of miR-34a and Klotho reduction in obstructed kidney, and markedly ameliorated renal fibrosis in the Adriamycin nephropathy and UUO model mice. These findings suggested that miR-34a plays an important role in the progression of renal fibrosis, which provides new insights into the pathogenesis and treatment of CKD.


Assuntos
Fibrose/tratamento farmacológico , Glucuronidase/genética , Nefropatias/tratamento farmacológico , MicroRNAs/genética , Fator de Crescimento Transformador beta1/genética , Animais , Linhagem Celular , Modelos Animais de Doenças , Doxorrubicina/toxicidade , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose/induzido quimicamente , Fibrose/genética , Fibrose/patologia , Flavonóis/farmacologia , Glucuronidase/antagonistas & inibidores , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/genética , Nefropatias/patologia , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Proteínas Klotho , Camundongos , MicroRNAs/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Obstrução Ureteral/induzido quimicamente , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/genética , Obstrução Ureteral/patologia
15.
Plant Dis ; 2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33373281

RESUMO

Maize (Zea mays L.) stalk rot, caused primarily by the soil-borne fungal pathogen Fusarium spp., reduces maize quality and yield worldwide. This study was undertaken to develop and utilize a rapid continuous injection inoculation technique to evaluate maize inbred lines for resistance to Fusarium spp. under field conditions, which could facilitate the identification and development of new sources of host resistance to manage the disease. Continuous injection inoculation is a rapid, stable, and simple method that can evaluate the resistance of maize inbred lines to Fusarium stalk rot (FSR) within 20 days. To verify the feasibility and reliability of inoculation method, Fusarium graminearum, F. proliferatum, and F. subglutinans were isolated, identified, and inoculated into maize at the six-leaf stage (V6) by a veterinary adjustable bottle continuous vaccination syringe. Our results showed that out of a total of 97 inbred maize lines, six (6.2%) showed high resistance to maize stalk rot, 20 showed resistance (20.6%), 32 were susceptible (33.0%), and 39 were very susceptible (40.2%). Based on simple sequence repeat (SSR) markers, an analysis of molecular variance indicated a significant correlation between population of the inbred maize line and resistance to FSR (P = 0.001). Overall, this study provided a systematic, rapid, stable, and simple identification method for maize inbred lines resistant to FSR in the field. At the same time, this method was also suitable for genetic diversity analysis of maize inbred lines resistant to FSR.

16.
J Environ Sci (China) ; 86: 50-64, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787190

RESUMO

Production of biochemicals from waste streams has been attracting increasing worldwide interest to achieve climate protection goals. Chain elongation (CE) for production of medium-chain carboxylic acids (MCCAs, especially caproate, enanthate and caprylate) from diverse biowaste has emerged as a potential economic and environmental technology for a sustainable society. The present mini review summarizes the research utilizing various synthetic or real waste-derived substrates available for MCCA production. Additionally, the microbial characteristics of the CE process are surveyed and discussed. Considering that a large proportion of recalcitrantly biodegradable biowaste and residues cannot be further utilized by CE systems and remain to be treated and disposed, we propose here a loop concept of bioconversion of biowaste to MCCAs making full use of the biowaste with zero emission. This could make possible an alternative technology for synthesis of value-added products from a wide range of biowaste, or even non-biodegradable waste (such as, plastics and rubbers). Meanwhile, the remaining scientific questions, unsolved problems, application potential and possible developments for this technology are discussed.


Assuntos
Eliminação de Resíduos de Serviços de Saúde/métodos , Caproatos , Caprilatos , Ácidos Carboxílicos
17.
Appl Environ Microbiol ; 84(22)2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30217839

RESUMO

Carbon chain elongation (CCE), a reaction within the carboxylate platform that elongates short-chain to medium-chain carboxylates by mixed culture, has attracted worldwide interest. The present study provides insights into the microbial diversity and predictive microbial metabolic pathways of a mixed-culture CCE microbiome on the basis of a comparative analysis of the metagenome and metatranscriptome. We found that the microbial structure of an acclimated chain elongation microbiome was a highly similar to that of the original inoculating biogas reactor culture; however, the metabolic activities were completely different, demonstrating the high stability of the microbial structure and flexibility of its functions. Additionally, the fatty acid biosynthesis (FAB) pathway, rather than the well-known reverse ß-oxidation (RBO) pathway for CCE, was more active and pivotal, though the FAB pathway had more steps and consumed more ATP, a phenomenon that has rarely been observed in previous CCE studies. A total of 91 draft genomes were reconstructed from the metagenomic reads, of which three were near completion (completeness, >97%) and were assigned to unknown strains of Methanolinea tarda, Bordetella avium, and Planctomycetaceae The last two strains are likely new-found active participators of CCE in the mixed culture. Finally, a conceptual framework of CCE, including both pathways and the potential participators, was proposed.IMPORTANCE Carbon chain elongation means the conversion of short-chain volatile fatty acids to medium-chain carboxylates, such as n-caproate and n-caprylate with electron donors under anaerobic condition. This bio-reaction can both expand the resource of valuable biochemicals and broaden the utilization of low-grade organic residues in a sustainable biorefinery context. Clostridium kluyveri is conventionally considered model microbe for carbon chain elongation which uses the reverse ß-oxidation pathway. However, little is known about the detailed microbial structure and function of other abundant microorganism in a mixed culture (or open culture) of chain elongation. We conducted the comparative metagenomic and metatranscriptomic analysis of a chain elongation microbiome to throw light on the underlying functional microbes and alternative pathways.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Carbono/metabolismo , Microbiota , Trifosfato de Adenosina/metabolismo , Bactérias/classificação , Bactérias/isolamento & purificação , Biocombustíveis/análise , Reatores Biológicos/microbiologia , Genoma Bacteriano , Metagenoma
18.
Front Neurol ; 15: 1340085, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327626

RESUMO

Background and purpose: Perforator artery disease (PAD) is an important subtype of ischemic stroke. The risk factors affecting the prognosis of patients with PAD are unclear. This study aimed to investigate the risk factors affecting the unfavorable prognosis of PAD. Methods: Patients with PAD were enrolled from Dushu Lake Hospital Affiliated to Soochow University and diagnosed as stroke with PAD during the period from September 2021 to July 2023 and followed up with a modified Rankin Scale (mRS) after 90 days, defining the mRS of 0-2 as a group with favorable prognosis, and 3-6 as a group with unfavorable functional outcome. Logistic regression was used to identify predictors for PAD. Multiple logistic regression analysis and receiver operating characteristics (ROC) were used to identify predictors of unfavorable prognosis. Results: Of the 181 enrolled patients, 48 (26.5%) were identified with unfavorable prognosis. On multivariate analysis, increased age (OR = 1.076, 95% CI: 1.012 ~ 1.144, p = 0.019), higher National Institutes of Health Stroke Scale (NIHSS) score at admission (OR = 2.930, 95% CI: 1. 905 ~ 4.508, p < 0.001), and increased neutrophil-to-lymphocyte ratio (NLR) (OR = 3.028, 95% CI: 1.615 ~ 5.675, p = 0.001) were independent risk factors for unfavorable prognosis in patients with PAD, and the area under the receiver operating characteristic curve was 0.590, 0.905, and 0.798, and the multi-factor diagnostic model (Model 2) showed reliable diagnostic specificity and sensitivity (area under the curve = 0.956, p < 0.001, specificity 0.805, sensitivity 0.958, accuracy 0.845). Conclusion: Increased baseline NLR and NIHSS score and aging may be independent risk factors for unfavorable prognosis of patients with PAD. NLR can be used as a potential biological indicator to predict the prognosis of stroke with PAD.

19.
Pest Manag Sci ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258464

RESUMO

BACKGROUND: The whitefly Bemisia tabaci is one of the world's foremost agricultural pests. Recently, we found that a wild relative of tobacco (Nicotiana benthamiana) demonstrates remarkable attractiveness and nearly 100% lethality towards whiteflies. Therefore, it can act as a dead-end trap crop for whitefly control in the field. However, the underlying mechanism of the significant attractiveness of N. benthamiana towards whiteflies is unclear. RESULTS: Binary-choice assays and olfactory experiments showed that compared to common tobacco (N. tabacum), the volatile of N. benthamiana has a greater attraction to whiteflies. Then we analyzed and compared volatiles from these two Nicotiana species by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). We identified 16 chemical compounds that are more abundant in N. benthamiana than in N. tabacum. Seven compounds were further tested with olfactometer assays and we found that, among them, undecane strongly attracted whiteflies. Further experiments revealed that even 0.005 µg mL-1 undecane is attractive to whiteflies. We also silenced the genes that may influence the biosynthesis of undecane and found the production of undecane decreased after silencing NbCER3, and that N. benthamiana plants with less undecane lost their attraction to whiteflies. In addition, we found that applying 0.005 µg mL-1 undecane on yellow sticky traps can increase the number of stuck insects on the traps by ≈40%. CONCLUSION: Undecane from the volatile of N. benthamiana is a critical chemical signal that attracts whiteflies and NbCER3 involved in the biosynthesis of undecane. Undecane may be used to improve the efficiency of yellow sticky traps for whitefly control. © 2024 Society of Chemical Industry.

20.
iScience ; 26(9): 107658, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37664633

RESUMO

Humans can distinguish flying birds from drones based solely on motion features when no image information is available. However, it remains unclear which motion features of animate motion induce our animacy perception. To address this, we first analyzed the differences in centroid motion between birds and drones, and discovered that birds exhibit greater acceleration, angular speed, and trajectory fluctuations. We further determined the order of their importance in evoking animacy perception was trajectory fluctuations, acceleration, and speed. More interestingly, people judge whether a moving object is alive using a feature-matching strategy, implying that animacy perception is induced in a key feature-triggered way rather than relying on the accumulation of evidence. Our findings not only shed light on the critical motion features that induce animacy perception and their relative contributions but also have important implications for developing target classification algorithms based on motion features.

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