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1.
Proc Natl Acad Sci U S A ; 121(13): e2313239121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38498710

RESUMO

High-entropy alloy nanoparticles (HEANs) possessing regulated defect structure and electron interaction exhibit a guideline for constructing multifunctional catalysts. However, the microstructure-activity relationship between active sites of HEANs for multifunctional electrocatalysts is rarely reported. In this work, HEANs distributed on multi-walled carbon nanotubes (HEAN/CNT) are prepared by Joule heating as an example to explain the mechanism of trifunctional electrocatalysis for oxygen reduction, oxygen evolution, and hydrogen evolution reaction. HEAN/CNT excels with unmatched stability, maintaining a 0.8V voltage window for 220 h in zinc-air batteries. Even after 20 h of water electrolysis, its performance remains undiminished, highlighting exceptional endurance and reliability. Moreover, the intrinsic characteristics of the defect structure and electron interaction for HEAN/CNT are investigated in detail. The electrocatalytic mechanism of trifunctional electrocatalysis of HEAN/CNT under different conditions is identified by in situ monitoring and theoretical calculation. Meanwhile, the electron interaction and adaptive regulation of active sites in the trifunctional electrocatalysis of HEANs were further verified by density functional theory. These findings could provide unique ideas for designing inexpensive multifunctional high-entropy electrocatalysts.

2.
Small ; 20(7): e2305390, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37797192

RESUMO

A FeCo/DA@NC catalyst with the well-defined FeCoN6 moiety is customized through a novel and ultrafast Joule heating technique. This catalyst demonstrates superior oxygen reduction reaction activity and stability in an alkaline environment. The power density and charge-discharge cycling of znic-air batteries driven by FeCo/DA@NC also surpass those of Pt/C catalyst. The source of the excellent oxygen reduction reaction activity of FeCo/DA@NC originates from the significantly changed charge environment and 3d orbital spin state. These not only improve the bonding strength between active sites and oxygen-containing intermediates, but also provide spare reaction sites for oxygen-containing intermediates. Moreover, various in situ detection techniques reveal that the rate-determining step in the four-electron oxygen reduction reaction is *O2 protonation. This work provides strong support for the precise design and rapid preparation of bimetallic catalysts and opens up new ideas for understanding orbital interactions during oxygen reduction reactions.

3.
Environ Geochem Health ; 46(10): 373, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167340

RESUMO

Combined electrokinetic remediation employing reducing agents represents an extensively utilized approach for the remediation of hexavalent chromium (Cr(VI))-contaminated soil. In this investigation, electrokinetic remediation of artificially contaminated kaolin was conducted utilizing a separate circulation system for the anolyte, with a 0.5M solution of acetic acid (HAc) as the electrolyte and foamed iron serving as the anode. The experimental outcomes demonstrated that employing HAc as the electrolyte enhances the electromigration of Cr(VI) and establishes an acidic milieu conducive to the reduction of Cr(VI) by foamed iron, thereby facilitating the rapid reduction of Cr(VI) accumulated in the anolyte through electrokinetic remediation. In the self-prepared contaminated kaolin, the initial concentration of Cr(VI) was 820.26 mg/L. Following the remediation process under optimal experimental conditions, the concentration was significantly reduced to 11.6 mg/L, achieving a removal efficiency of Cr(VI) in the soil of 98.59%. In the optimal experimental setup, the Cr(VI) concentration in the anolyte was reduced to 0.05 mg/L, which is below the EPA's Safe Drinking Water Act standard for Cr(VI) content of 0.1 mg/L. The removal mechanism of Cr(VI) from the electrolyte primarily involves reduction, precipitation, and co-precipitation, with the foamed iron playing a predominant role. HAc and foamed iron exhibit a synergistic effect. The findings of this study substantiate that the integration of foamed iron with HAc is efficacious for the electrokinetic remediation of soil contaminated with Cr(VI).


Assuntos
Ácido Acético , Cromo , Eletrodos , Recuperação e Remediação Ambiental , Ferro , Caulim , Poluentes do Solo , Cromo/química , Recuperação e Remediação Ambiental/métodos , Caulim/química , Poluentes do Solo/química , Ácido Acético/química , Ferro/química , Eletrólitos/química
4.
Angew Chem Int Ed Engl ; 62(27): e202303871, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37133306

RESUMO

A novel type of covalent organic frameworks has been developed by assembling definite cobalt-nitrogen-carbon configurations onto carbon nanotubes using linkers that have varying electronic effects. This innovative approach has resulted in an efficient electrocatalyst for oxygen reduction, which is understood by a combination of in situ spectroelectrochemistry and the bond order theorem. The strong interaction between the electron-donating carbon nanotubes and the electron-accepting linker mitigates the trend of charge loss at cobalt sites, while inducing the generation of high spin state. This enhances the adsorption strength and electron transfer between the cobalt center and reactants/intermediates, leading to an improved oxygen reduction capability. This work not only presents an effective strategy for developing efficient non-noble metal electrocatalysts through reticular chemistry, but also provides valuable insights into regulating the electronic configuration and charge behavior of active sites in designing high-performance electrocatalysts.

5.
Plant Physiol ; 187(1): 303-320, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-34618128

RESUMO

The energy allocation for vegetative and reproductive growth is regulated by developmental signals and environmental cues, which subsequently affects seed output. However, the molecular mechanism underlying how plants coordinate yield-related traits to control yield in changing source-sink relationships remains largely unknown. Here, we discovered the lectin receptor-like kinase LecRK-VIII.2 as a specific receptor-like kinase that coordinates silique number, seed size, and seed number to determine seed yield in Arabidopsis (Arabidopsis thaliana). The lecrk-VIII.2 mutants develop smaller seeds, but more siliques and seeds, leading to increased yield. In contrast, the plants overexpressing LecRK-VIII.2 form bigger seeds, but less siliques and seeds, which results in similar yield to that of wild-type plants. Interestingly, LecRK-VIII.2 promotes the growth of the rosette, root, and stem by coordinating the source-sink relationship. Additionally, LecRK-VIII.2 positively regulates cell expansion and proliferation in the seed coat, and maternally controls seed size. The genetic and biochemical analyses demonstrated that LecRK-VIII.2 acts upstream of the mitogen-activated protein kinase (MAPK) gene MPK6 to regulate silique number, seed size, and seed number. Collectively, these findings uncover LecRK-VIII.2 as an upstream component of the MAPK signaling pathway to control yield-related traits and suggest its potential for crop improvement aimed at developing plants with stable yield, a robust root system, and improved lodging resistance.


Assuntos
Arabidopsis , Proteínas Quinases Ativadas por Mitógeno , Transdução de Sinais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas Quinases Ativadas por Mitógeno/genética
6.
Mar Drugs ; 20(6)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35736191

RESUMO

Carbohydrate-active enzymes (CAZymes) are an important characteristic of bacteria in marine systems. We herein describe the CAZymes of Paenibacillus algicola HB172198T, a novel type species isolated from brown algae in Qishui Bay, Hainan, China. The genome of strain HB172198T is a 4,475,055 bp circular chromosome with an average GC content of 51.2%. Analysis of the nucleotide sequences of the predicted genes shows that strain HB172198T encodes 191 CAZymes. Abundant putative enzymes involved in the degradation of polysaccharides were identified, such as alginate lyase, agarase, carrageenase, xanthanase, xylanase, amylases, cellulase, chitinase, fucosidase and glucanase. Four of the putative polysaccharide lyases from families 7, 15 and 38 were involved in alginate degradation. The alginate lyases of strain HB172198T exhibited the maximum activity 152 U/mL at 50 °C and pH 8.0, and were relatively stable at pH 7.0 and temperatures lower than 40 °C. The average degree of polymerization (DP) of the sodium alginate oligosaccharide (AOS) degraded by the partially purified alginate lyases remained around 14.2, and the thin layer chromatography (TCL) analysis indicated that it contained DP2-DP8 oligosaccharides. The complete genome sequence of P. algicola HB172198T will enrich our knowledge of the mechanism of polysaccharide lyase production and provide insights into its potential applications in the degradation of polysaccharides such as alginate.


Assuntos
Paenibacillus , Polissacarídeo-Liases , Polissacarídeos , Alginatos/metabolismo , Oligossacarídeos/metabolismo , Paenibacillus/metabolismo , Polissacarídeo-Liases/metabolismo , Polissacarídeos/metabolismo , Especificidade por Substrato
7.
BMC Genomics ; 22(1): 298, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892645

RESUMO

BACKGROUND: Chloroplasts are important semi-autonomous organelles in plants and algae. Unlike higher plants, the chloroplast genomes of green algal linage have distinct features both in organization and expression. Despite the architecture of chloroplast genome having been extensively studied in higher plants and several model species of algae, little is known about the transcriptional features of green algal chloroplast-encoded genes. RESULTS: Based on full-length cDNA (Iso-Seq) sequencing, we identified widely co-transcribed polycistronic transcriptional units (PTUs) in the green alga Caulerpa lentillifera. In addition to clusters of genes from the same pathway, we identified a series of PTUs of up to nine genes whose function in the plastid is not understood. The RNA data further allowed us to confirm widespread expression of fragmented genes and conserved open reading frames, which are both important features in green algal chloroplast genomes. In addition, a newly fragmented gene specific to C. lentillifera was discovered, which may represent a recent gene fragmentation event in the chloroplast genome. With the newly annotated exon-intron boundary information, gene structural annotation was greatly improved across the siphonous green algae lineages. Our data also revealed a type of non-canonical Group II introns, with a deviant secondary structure and intronic ORFs lacking known splicing or mobility domains. These widespread introns have conserved positions in their genes and are excised precisely despite lacking clear consensus intron boundaries. CONCLUSION: Our study fills important knowledge gaps in chloroplast genome organization and transcription in green algae, and provides new insights into expression of polycistronic transcripts, freestanding ORFs and fragmented genes in algal chloroplast genomes. Moreover, we revealed an unusual type of Group II intron with distinct features and conserved positions in Bryopsidales. Our data represents interesting additions to knowledge of chloroplast intron structure and highlights clusters of uncharacterized genes that probably play important roles in plastids.


Assuntos
Clorófitas , RNA , Clorófitas/genética , Cloroplastos/genética , Íntrons/genética , Filogenia , Análise de Sequência de RNA
8.
BMC Plant Biol ; 21(1): 380, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34407757

RESUMO

BACKGROUND: The C2H2-type zinc finger proteins (C2H2-ZFPs) are one of major classes of transcription factors that play important roles in plant growth, development and stress responses. Limit information about the C2H2-ZF genes hinders the molecular breeding in bread wheat (Triticum aestivum). RESULTS: In this study, 457 C2H2-ZFP proteins (including 253 splice variants), which contain four types of conserved domain (named Q, M, Z, and D), could be further classified into ten subsets. They were identified to be distributed in 21 chromosomes in T. aestivum. Subset-specific motifs, like NPL-, SFP1-, DL- (EAR-like-motif), R-, PL-, L- and EK-, might make C2H2-ZFP diverse multifunction. Interestingly, NPL- and SFP1-box were firstly found to be located in C2H2-ZFP proteins. Synteny analyses showed that only 4 pairs of C2H2 family genes in T. aestivum, 65 genes in B. distachyon, 66 genes in A. tauschii, 68 genes in rice, 9 genes in Arabidopsis, were syntenic relationships respectively. It indicated that TaZFPs were closely related to genes in Poaceae. From the published transcriptome data, totally 198 of 204 TaC2H2-ZF genes have expression data. Among them, 25 TaC2H2-ZF genes were certificated to be significantly differentially expressed in 5 different organs and 15 different development stages by quantitative RT-PCR. The 18 TaC2H2-ZF genes were verified in response to heat, drought, and heat & drought stresses. According to expression pattern analysis, several TaZFPs, like Traes_5BL_D53A846BE.1, were not only highly expressed in L2DAAs, RTLS, RMS, but also endowed tolerance to drought and heat stresses, making them good candidates for molecular breeding. CONCLUSIONS: This study systematically characterized the TaC2H2-ZFPs and their potential roles in T. aestivum. Our findings provide new insights into the C2H2-ZF genes in T. aestivum as well as a foundation for further studies on the roles of TaC2H2-ZF genes in T. aestivum molecular breeding.


Assuntos
Dedos de Zinco CYS2-HIS2/genética , Perfilação da Expressão Gênica , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Triticum/genética , Triticum/metabolismo , Dedos de Zinco/genética , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genoma de Planta , Filogenia
9.
Int J Syst Evol Microbiol ; 70(3): 1639-1643, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32125262

RESUMO

A Gram-stain-negative, aerobic, rod-shaped bacterium with peritrichous flagella, designated strain HB161719T, was isolated from coastal sand collected from Tanmen Port in Hainan, PR China. The isolate was found to grow with 2-11 % (w/v) NaCl, at 15-45 °C and pH 6.0-10.0, with an optima of 2-3 % NaCl, 37 °C and pH 7.0, respectively. Chemotaxonomic analysis showed that Q-8 was detected as the sole respiratory quinone and that iso-C15 : 0 and summed features 3, 8 and 9 were the major cellular fatty acids. The G+C content of the genomic DNA was 58.2 mol%. Analysis of the 16S rRNA gene sequence of the strain showed an affiliation with the genus Microbulbifer, sharing 98.7, 98.4, 97.8 and 97.8 % sequence similarities to the closest relatives of Microbulbifer okinawensis ABABA23T, Microbulbifer pacificus SPO729T, Microbulbifer taiwanensis CC-LN1-12T and Microbulbifer gwangyangensis GY2T, respectively. Low DNA-DNA hybridization values showed that it formed a distinct genomic species. The combined phenotypic and molecular features supported that strain HB161719T represents a novel species of the genus Microbulbifer, for which the name Microbulbifer harenosus sp. nov. is proposed. The type strain is HB161719T (=CGMCC 1.13584T=JCM 32688T).


Assuntos
Alteromonadaceae/classificação , Filogenia , Areia/microbiologia , Alginatos/metabolismo , Alteromonadaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
10.
Int J Syst Evol Microbiol ; 70(3): 1516-1521, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935177

RESUMO

An alginate lyase-excreting bacterium, designated strain HB161718T, was isolated from coastal sand collected from Tanmen Port in Hainan, PR China. Cells were Gram-stain-negative rods and motile with a single polar flagellum. Its major isoprenoid quinone was ubiquinone 8 (Q-8), and its cellular fatty acid profile mainly consisted of C16 : 1 ω7c and/or C16 : 1 ω6c, C18 : 1 ω6c and/or C18 : 1 ω7c, C16 : 0, C17 : 0 10-methyl and C16 : 0 N alcohol. The G+C content of the genomic DNA was 44.1 mol%. 16S rRNA gene sequence analysis suggested that strain HB161718T belonged to the genus Alteromonas, sharing 99.5, 99.4, 99.2, 98.9 and 98.5 % sequence similarities to its closest relatives, Alteromonas macleodii JCM 20772T, Alteromonas gracilis 9a2T, Alteromonas australica H17T, Alteromonas marina SW-47T and Alteromonas mediterranea DET, respectively. The low values of DNA-DNA hybridization and average nucleotide identity showed that it formed a distinct genomic species. The combined phenotypic and molecular features supported the conclusion that strain HB161718T represents a novel species of the genus Alteromonas, for which the name Alteromonas portus sp. nov. is proposed. The type strain is HB161718T (=CGMCC 1.13585T=JCM 32687T).


Assuntos
Alteromonas/classificação , Filogenia , Polissacarídeo-Liases , Areia/microbiologia , Alteromonas/enzimologia , Alteromonas/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
11.
Int J Syst Evol Microbiol ; 70(9): 5087-5092, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32790602

RESUMO

A Gram-stain-variable, facultatively anaerobic, endospore-forming, rod-shaped bacterium, designated HB172198T, was isolated from brown alga collected at Qishui Bay, Hainan, PR China. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain HB172198T belonged to the genus Paenibacillus, and the closest phylogenetically related species was Paenibacillus lemnae NBRC 109972T (97.6% similarity). The other 16S rRNA gene sequence similarities were under 97.0%. The whole genome average nucleotide identity value between strain HB172198T and the closest type strain was 75.3% and the in silico DNA-DNA hybridization value was 20.2%. The predominant isoprenoid quinone was menaquinone 7 and the major fatty acids were anteiso-C15:0, C16:0, anteiso-C17:0, iso C16:0 and C16:1 ω11c. The combined phylogenetic relatedness, phenotypic and genotypic features supported the conclusion that strain HB172198T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus algicola sp. nov. is proposed. The type strain is HB172198T (=CGMCC 1.13583T=JCM 32683T).


Assuntos
Paenibacillus/classificação , Phaeophyceae/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Paenibacillus/enzimologia , Paenibacillus/isolamento & purificação , Polissacarídeo-Liases , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Int J Syst Evol Microbiol ; 68(10): 3080-3083, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30152750

RESUMO

A novel aerobic actinomycete, designated as HA15955T, was isolated from a mangrove mud sample collected in Sanya, China. Scanning electron microscopy revealed that HA15955T produced straight to spiral spore chains with smooth cylindrical spores. 16S rRNA gene sequence similarity showed that strain HA15955T belonged to the genus Streptomyces, was most closely related to Streptomyces speibonae NRRL B-24240T (98.7 % similarity) and formed a distinct subclade. The low relatedness value of DNA-DNA hybridization showed that it formed a distinct genomic species. Based on phenotypic, genotypic and phylogenetic data, strain HA15955T should be classified as a novel species of the genus Streptomyces, for which the name Streptomycescaeni sp. nov. is proposed. The type strain is HA15955T (=CGMCC 4.7426T=DSM 105693T).


Assuntos
Filogenia , Rhizophoraceae/microbiologia , Microbiologia do Solo , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/genética , Streptomyces/isolamento & purificação
14.
Int J Syst Evol Microbiol ; 68(10): 3144-3148, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30179151

RESUMO

A novel aerobic actinomycete, designated HA15826T, was isolated from a mangrove soil sample collected in Sanya, China. Scanning electron microscopy revealed that the isolate produced straight to slightly flexural spore chains with rough cylindrical spores. Chemotaxonomic tests showed that the cell wall contained meso-diaminopimelic acid and the major fatty acids were iso-C16 : 0, 10-methyl-C17 : 0, C17 : 1ω8c and C16 : 0. 16S rRNA gene sequence similarity analysis showed that strain HA15826T belonged to the genus Nonomuraea, being most closely related to Nonomuraea dietziae DSM 44320T (98.7 %), Nonomuraea candida HMC10T (98.4 %), Nonomuraea africana IFO 14745T (98.4 %), Nonomuraea roseola IFO 14685T (98.2 %) and Nonomuraea recticatena IFO 14525T (98.1 %). The DNA G+C content of the type strain is 73.2 %. DNA-DNA relatedness and comparative analyses of physiological, biochemical and chemotaxonomic data allowed genotypic and phenotypic differentiation of strain HA15826T from the closely related species. Thus, strain HA15826T should be classified as a novel species of the genus Nonomuraea, for which the name Nonomuraeamangrovi sp. nov. is proposed. The type strain is HA15826T (=CGMCC 4.7425T=DSM 105694T).


Assuntos
Actinomycetales/classificação , Filogenia , Rhizophoraceae/microbiologia , Microbiologia do Solo , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Int J Syst Evol Microbiol ; 67(4): 795-799, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27902310

RESUMO

Two Gram-stain-positive, facultatively aerobic, endospore-forming and rod-shaped bacteria, designated DB13031T and DB13311, were isolated from the soil of the Jiaxi Nature Reserve in Hainan, PR China. 16S rRNA gene analysis of strains DB13031T and DB13311 showed that they fell within the Paenibacillus cluster, with highest similarities to Paenibacillus cucumis AP-115T (98.4 and 98.3 %, respectively), Paenibacillus barcinonensis BP-23T (98.3 and 98.2 %, respectively) and Paenibacillus oceanisediminis L10T (97.7 and 97.7 %, respectively). The DNA-DNA hybridization values between strain DB13031T and the type strains of its closest related species were 48.2, 38.1 and 43.5 %. Strain DB13031T contained menaquinone-7 (MK-7) as the predominant isoprenoid quinone and anteiso-C15 : 0, iso-C16 : 0 and C16 : 0 as the major cellular fatty acids. The cell-wall peptidoglycan was of the A1γ type and the major polar lipid profiles were diphosphatidylglycerol, phosphatidylethanolamine, four unknown aminophospholipids and four unknown phospholipids. Based on the phenotypic and genotypic data, it is proposed that the two isolates represent a novel species of the genus Paenibacillus, for which the name Paenibacillus silvae sp. nov. is proposed. The type strain is DB13031T (=CGMCC 1.12770T=DSM 28013T).


Assuntos
Paenibacillus/classificação , Filogenia , Floresta Úmida , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/isolamento & purificação , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
BMC Plant Biol ; 15: 149, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26084405

RESUMO

BACKGROUND: Miniature inverted repeat transposable elements (MITEs) are important components of eukaryotic genomes, with hundreds of families and many copies, which may play important roles in gene regulation and genome evolution. However, few studies have investigated the molecular mechanisms involved. In our previous study, a Tourist-like MITE, Monkey King, was identified from the promoter region of a flowering time gene, BnFLC.A10, in Brassica napus. Based on this MITE, the characteristics and potential roles on gene regulation of the MITE family were analyzed in Brassicaceae. RESULTS: The characteristics of the Tourist-like MITE family Monkey King in Brassicaceae, including its distribution, copies and insertion sites in the genomes of major Brassicaceae species were analyzed in this study. Monkey King was actively amplified in Brassica after divergence from Arabidopsis, which was indicated by the prompt increase in copy number and by phylogenetic analysis. The genomic variations caused by Monkey King insertions, both intra- and inter-species in Brassica, were traced by PCR amplification. Genomic sequence analysis showed that most complete Monkey King elements are located in gene-rich regions, less than 3kb from genes, in both the B. rapa and A. thaliana genomes. Sixty-seven Brassica expressed sequence tags carrying Monkey King fragments were also identified from the NCBI database. Bisulfite sequencing identified specific DNA methylation of cytosine residues in the Monkey King sequence. A fragment containing putative TATA-box motifs in the MITE sequence could bind with nuclear protein(s) extracted from leaves of B. napus plants. A Monkey King-related microRNA, bna-miR6031, was identified in the microRNA database. In transgenic A. thaliana, when the Monkey King element was inserted upstream of 35S promoter, the promoter activity was weakened. CONCLUSION: Monkey King, a Brassicaceae Tourist-like MITE family, has amplified relatively recently and has induced intra- and inter-species genomic variations in Brassica. Monkey King elements are most abundant in the vicinity of genes and may have a substantial effect on genome-wide gene regulation in Brassicaceae. Monkey King insertions potentially regulate gene expression and genome evolution through epigenetic modification and new regulatory motif production.


Assuntos
Brassicaceae/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Sequências Repetidas Invertidas/genética , Arabidopsis/genética , Composição de Bases/genética , Sequência de Bases , Mapeamento Cromossômico , Simulação por Computador , Metilação de DNA/genética , Ensaio de Desvio de Mobilidade Eletroforética , Genoma de Planta , MicroRNAs/genética , MicroRNAs/metabolismo , Dados de Sequência Molecular , Mutagênese Insercional/genética , Proteínas Nucleares/metabolismo , Filogenia , Plantas Geneticamente Modificadas , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Especificidade da Espécie
17.
Int J Syst Evol Microbiol ; 65(9): 3086-3090, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26297343

RESUMO

A novel aerobic actinomycete, designated HA11110(T), was isolated from a mangrove soil sample collected in Haikou, China. It formed white aerial mycelium and pale yellow substrate mycelium on Gause's synthetic agar no. 1. Scanning electron microscopy revealed that cells of HA11110(T) produced straight to spiral spore chains with spiny spores. Chemotaxonomic tests showed that the cell wall contained LL-diaminopimelic acid and the major fatty acids were iso-C16 : 0, anteiso-C15 : 0 and iso-C14 : 0.16S rRNA gene sequence similarity showed that strain HA11110(T) belonged to the genus Streptomyces, most closely related to Streptomyces fenghuangensis GIMN4.003(T) (99.1%), Streptomyces nanhaiensis SCSIO 01248(T) (98.8%) and Streptomyces radiopugnans R97(T) (98.8%). However, DNA-DNA hybridization studies of strain HA11110T with these three closest relatives showed relatedness values of 58.4, 49.7 and 47.2%, respectively. On the basis of phenotypic and genotypic data, strain HA11110(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces mangrovi sp. nov. is proposed. The type strain is HA11110(T) ( = CGMCC 4.7117(T)= DSM 42113(T)).


Assuntos
Streptomyces , China , DNA Bacteriano/genética , Ácido Diaminopimélico , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Hibridização de Ácido Nucleico/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Microbiologia do Solo , Streptomyces/classificação
18.
Front Plant Sci ; 15: 1440951, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39297014

RESUMO

Introduction: The Grain for Green Project (GGP) by the Chinese government was an important vegetation restoration project in ecologically fragile and severely degraded karst regions. Soil fungi play a facilitating role in the cycling of nutrients both above and below the ground, which is crucial for maintaining ecosystem function and stability. In karst regions, their role is particularly critical due to the unique geological and soil characteristics, as they mitigate soil erosion, enhance soil fertility, and promote vegetation growth. However, little is known about how the implementation of this project shifts the co-occurrence network topological features and assembly processes of karst soil fungi, which limits our further understanding of karst vegetation restoration. Methods: By using MiSeq high-throughput sequencing combined with null model analysis technology, we detected community diversity, composition, co-occurrence networks, and assembly mechanisms of soil fungi under three GGP patterns (crop, grassland, and plantation) in the southwestern karst region. Results: Ascomycota and Basidiomycota were the main fungal phyla in all the karst soils. Returning crop to plantation and grassland had no significant effect on α diversity of soil fungi (P > 0.05), but did significantly affect the ß diversity (P = 0.001). Soil moisture and total nitrogen (TN) were the main factors affecting the community structure of soil fungi. Compared with crop, soil fungi networks in grassland and plantation exhibited a higher nodes, edges, degree, and relatively larger network size, indicating that vegetation restoration enhanced fungal interactions. The soil fungi networks in grassland and plantation were more connected than those in crop, implying that the interaction between species was further strengthened after returning the crop to plantation and grassland. In addition, null-model analysis showed that the assembly process of soil fungal communities from crop to grassland and plantation shifted from an undominant process to dispersal limitation. Discussion: These data indicated that GGP in karst region changed the composition and assembly mechanisms of the soil fungal community and enhanced the interaction between fungal species, which can contribute to a better understanding of the fungal mechanisms involved in the restoration of degraded karst soils through vegetation recovery.

19.
Plants (Basel) ; 13(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38611471

RESUMO

The mitogen-activated protein kinase (MAPK) cascades act as crucial signaling modules that regulate plant growth and development, response to biotic/abiotic stresses, and plant immunity. MAP3Ks can be activated through MAP4K phosphorylation in non-plant systems, but this has not been reported in plants to date. Here, we identified a total of 234 putative TaMAPK family members in wheat (Triticum aestivum L.). They included 48 MAPKs, 17 MAP2Ks, 144 MAP3Ks, and 25 MAP4Ks. We conducted systematic analyses of the evolution, domain conservation, interaction networks, and expression profiles of these TaMAPK-TaMAP4K (representing TaMAPK, TaMAP2K, TaMAP3K, and TaMAP4K) kinase family members. The 234 TaMAPK-TaMAP4Ks are distributed on 21 chromosomes and one unknown linkage group (Un). Notably, 25 of these TaMAP4K family members possessed the conserved motifs of MAP4K genes, including glycine-rich motif, invariant lysine (K) motif, HRD motif, DFG motif, and signature motif. TaMAPK3 and 6, and TaMAP4K10/24 were shown to be strongly expressed not only throughout the growth and development stages but also in response to drought or heat stress. The bioinformatics analyses and qRT-PCR results suggested that wheat may activate the MAP4K10-MEKK7-MAP2K11-MAPK6 pathway to increase drought resistance in wheat, and the MAP4K10-MAP3K8-MAP2K1/11-MAPK3 pathway may be involved in plant growth. In general, our work identified members of the MAPK-MAP4K cascade in wheat and profiled their potential roles during their response to abiotic stresses and plant growth based on their expression pattern. The characterized cascades might be good candidates for future crop improvement and molecular breeding.

20.
Virol Sin ; 39(1): 156-168, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38253258

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen responsible for coronavirus disease 2019 (COVID-19), continues to evolve, giving rise to more variants and global reinfections. Previous research has demonstrated that barcode segments can effectively and cost-efficiently identify specific species within closely related populations. In this study, we designed and tested RNA barcode segments based on genetic evolutionary relationships to facilitate the efficient and accurate identification of SARS-CoV-2 from extensive virus samples, including human coronaviruses (HCoVs) and SARSr-CoV-2 lineages. Nucleotide sequences sourced from NCBI and GISAID were meticulously selected and curated to construct training sets, encompassing 1733 complete genome sequences of HCoVs and SARSr-CoV-2 lineages. Through genetic-level species testing, we validated the accuracy and reliability of the barcode segments for identifying SARS-CoV-2. Subsequently, 75 main and subordinate species-specific barcode segments for SARS-CoV-2, located in ORF1ab, S, E, ORF7a, and N coding sequences, were intercepted and screened based on single-nucleotide polymorphism sites and weighted scores. Post-testing, these segments exhibited high recall rates (nearly 100%), specificity (almost 30% at the nucleotide level), and precision (100%) performance on identification. They were eventually visualized using one and two-dimensional combined barcodes and deposited in an online database (http://virusbarcodedatabase.top/). The successful integration of barcoding technology in SARS-CoV-2 identification provides valuable insights for future studies involving complete genome sequence polymorphism analysis. Moreover, this cost-effective and efficient identification approach also provides valuable reference for future research endeavors related to virus surveillance.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , RNA , Reprodutibilidade dos Testes , Sequência de Bases
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