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1.
Mol Biol Evol ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850168

RESUMO

We developed phyloBARCODER (https://github.com/jun-inoue/phyloBARCODER), a new web tool that can identify short DNA sequences to the species level using metabarcoding. phyloBARCODER estimates phylogenetic trees based on uploaded anonymous DNA sequences and reference sequences from databases. Without such phylogenetic contexts, alternative, similarity-based methods independently identify species names and anonymous sequences of the same group by pairwise comparisons between queries and database sequences, with the caveat that they must match exactly or very closely. By putting metabarcoding sequences into a phylogenetic context, phyloBARCODER accurately identifies (1) species or classification of query sequences and (2) anonymous sequences associated with the same species or even with populations of query sequences, with clear and accurate explanations. Version 1 of phyloBARCODER stores a database comprising all eukaryotic mitochondrial gene sequences. Moreover, by uploading their own databases, phyloBARCODER users can conduct species identification specialized for sequences obtained from a local geographic region or those of non-mitochondrial genes, e.g., ITS or rbcL.

2.
Small ; 20(27): e2310239, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38299473

RESUMO

Solid-state hydrogen storage materials are safe and lightweight hydrogen carriers. Among the various solid-state hydrogen carriers, hydrogen boride (HB) sheets possess a high gravimetric hydrogen capacity (8.5 wt%). However, heating at high temperatures and/or strong ultraviolet illumination is required to release hydrogen (H2) from HB sheets. In this study, the electrochemical H2 release from HB sheets using a dispersion system in an organic solvent without other proton sources is investigated. H2 molecules are released from the HB sheets under the application of a cathodic potential. The Faradaic efficiency for H2 release from HB sheets reached >90%, and the onset potential for H2 release is -0.445 V versus Ag/Ag+, which is more positive than those from other proton sources, such as water or formic acid, under the same electrochemical conditions. The total electrochemically released H2 in a long-time experiment reached ≈100% of the hydrogen capacity of HB sheets. The H2 release from HB sheets is driven by a small bias; thus, they can be applied as safe and lightweight hydrogen carriers with economical hydrogen release properties.

3.
Fungal Genet Biol ; 170: 103860, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38114016

RESUMO

Fusarium oxysporum f. sp. cepae (Foc) is the causative agent of Fusarium basal rot disease in onions, which leads to catastrophic global crop production losses. Therefore, the interaction of Foc with its host has been actively investigated, and the pathogen-specific (PS) regions of the British strain Foc_FUS2 have been identified. However, it has not been experimentally determined whether the identified PS region plays a role in pathogenicity. To identify the pathogenicity chromosome in the Japanese strain Foc_TA, we initially screened effector candidates, defined as small proteins with a signal peptide that contain two or more cysteines, from genome sequence data. Twenty-one candidate effectors were identified, five of which were expressed during infection. Of the expressed effector candidates, four were located on the 4-Mb-sized chromosome in Foc_TA. To clarify the relationship between pathogenicity and the 4-Mb-sized chromosome in Foc_TA, nine putative 4-Mb-sized chromosome loss strains were generated by treatment with benomyl (a mitotic inhibitor drug). A pathogenicity test with putative 4-Mb-sized chromosome loss strains showed that these strains were impaired in their pathogenicity toward onions. Genome analysis of three putative 4-Mb-sized chromosome loss strains revealed that two strains lost a 4-Mb-sized chromosome in common, and another strain maintained a 0.9-Mb region of the 4-Mb-sized chromosome. Our findings show that the 4-Mb-sized chromosome is the pathogenicity chromosome in Foc_TA, and the 3.1-Mb region within the 4-Mb-sized chromosome is required for full pathogenicity toward onion.


Assuntos
Fusarium , Virulência/genética , Fusarium/genética , Cromossomos , Doenças das Plantas/genética
4.
Phys Chem Chem Phys ; 25(22): 15531-15538, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37249577

RESUMO

Two-dimensional hydrogen boride (HB) sheets prepared via the ion-exchange reaction from magnesium diboride (MgB2) are known to possess several intriguing properties for a wide range of applications; however, previous reports have shown that the sheets prepared using this method contain small amounts of reactive components, making them unsuitable for certain applications. Therefore, developing a method for preparing HB sheets that exhibit long-term stability and do not contain reactive species is essential. In this study, we developed an effective treatment method for achieving long-term stabilization of HB sheets. We found that by pre-treating the HB sheets with water and then filtering the dried product from an acetonitrile dispersion, we could achieve excellent long-term stability over nine months. This stability was maintained even outside of a glovebox, with no H2 released by the decomposition and/or reaction. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) absorption spectroscopy measurements revealed that the sample exhibited pure HB characteristics with negatively charged boron and B-H-B and terminal B-H bonds, even after nine months of storage. Furthermore, based on thermal desorption spectroscopy (TDS) measurements, the presence of reactive species in the as-prepared HB sheets is attributed to fluctuating B-H bonds with relatively weak binding energies that can be removed using the method developed in this study.

5.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769262

RESUMO

Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici (FOL), is a devastating soilborne disease in tomatoes. Magnesium oxide nanoparticles (MgO NPs) induce strong immunity against Fusarium wilt in tomatoes. However, the mechanisms underlying this immunity remain poorly understood. Comparative transcriptome analysis and microscopy of tomato roots were performed to determine the mechanism of MgO NP-induced immunity against FOL. Eight transcriptomes were prepared from tomato roots treated under eight different conditions. Differentially expressed genes were compared among the transcriptomes. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that in tomato roots pretreated with MgO NPs, Rcr3 encoding apoplastic protease and RbohD encoding NADPH oxidase were upregulated when challenge-inoculated with FOL. The gene encoding glycine-rich protein 4 (SlGRP4) was chosen for further analysis. SlGRP4 was rapidly transcribed in roots pretreated with MgO NPs and inoculated with FOL. Immunomicroscopy analysis showed that SlGRP4 accumulated in the cell walls of epidermal and vascular vessel cells of roots pretreated with MgO NPs, but upon FOL inoculation, SlGRP4 further accumulated in the cell walls of cortical tissues within 48 h. The results provide new insights into the probable mechanisms of MgO NP-induced tomato immunity against Fusarium wilt.


Assuntos
Fusarium , Nanopartículas , Solanum lycopersicum , Solanum lycopersicum/genética , Fusarium/genética , Óxido de Magnésio , Doenças das Plantas/genética
6.
Molecules ; 27(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36500350

RESUMO

Hydrogen boride (HB) sheets are two-dimensional materials comprising a negatively charged hexagonal boron network and positively charged hydrogen atoms with a stoichiometric ratio of 1:1. Herein, we report the spontaneous formation of highly dispersed Ni nanoclusters on HB sheets. The spontaneous reduction reaction of Ni ions by the HB sheets was monitored by in-situ measurements with an ultraviolet-visible spectrometer. Acetonitrile solutions of Ni complexes and acetonitrile dispersions of the HB sheets were mixed in several molar ratios (the HB:Ni molar ratio was varied from 100:0.5 to 100:20), and the changes in the absorbance were measured over time. In all cases, the results suggest that Ni metal clusters grow on the HB sheets, considering the increase in absorbance with time. The absorbance peak position shifts to the higher wavelength as the Ni ion concentration increases. Transmission electron microscopy images of the post-reaction products indicate the formation of Ni nanoclusters, with sizes of a few nanometers, on the HB sheets, regardless of the preparation conditions. These highly dispersed Ni nanoclusters supported on HB sheets will be used for catalytic and plasmonic applications and as hydrogen storage materials.


Assuntos
Hidrogênio , Catálise , Microscopia Eletrônica de Transmissão , Concentração de Íons de Hidrogênio
7.
Phys Chem Chem Phys ; 23(13): 7724-7734, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32870215

RESUMO

Two-dimensional hydrogen boride (HB) sheets were recently demonstrated to act as a solid acid catalyst in their hydrogen-deficient state. However, both the active sites and the mechanism of the catalytic process require further elucidation. In this study, we analyzed the conversion of ethanol adsorbed on HB sheets under vacuum during heating using in situ Fourier transform infrared (FT-IR) absorption spectroscopy with isotope labelling. Up to 450 K, the FT-IR peak associated with the OH group of the adsorbed ethanol molecule disappeared from the spectrum, which was attributed to a dehydration reaction with a hydrogen atom from the HB sheet, resulting in the formation of an ethyl species. At temperatures above 440 K, the number of BD bonds markedly increased in CD3CH2OH, compared to CH3CD2OH; the temperature dependence of the formation rate of BD bonds was similar to that of the dehydration reaction rate of ethanol on HB sheets under steady-state conditions. The rate-determining step of the dehydration of ethanol on HB was thus ascribed to the dehydrogenation of the methyl group of the ethyl species on the HB sheets, followed by the immediate desorption of ethylene. These results show that the catalytic ethanol dehydration process on HB involves the hydrogen atoms of the HB sheets. The obtained mechanistic insights are expected to promote the practical application of HB sheets as catalysts.

8.
Int J Mol Sci ; 22(12)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205396

RESUMO

Members of the lectin receptor-like kinase (LecRLKs) family play a vital role in innate plant immunity. Few members of the LecRLKs family have been characterized in rice and Arabidopsis, respectively. However, little literature is available about LecRLKs and their role against fungal infection in cucumber. In this study, 60 putative cucumber LecRLK (CsLecRLK) proteins were identified using genome-wide analysis and further characterized into L-type LecRLKs (24) and G-type LecRLKs (36) based on domain composition and phylogenetic analysis. These proteins were allocated to seven cucumber chromosomes and found to be involved in the expansion of the CsLecRLK gene family. Subcellular localization of CsaLecRLK9 and CsaLecRLK12 showed green fluorescence signals in the plasma membrane of leaves. The transcriptional profiling of CsLecRLK genes showed that L-type LecRLKs exhibited functional redundancy as compared to G-type LecRLKs. The qRT-PCR results indicated that both L- and G-type LecRLKs showed significant response against plant growth-promoting fungi (PGPF-Trichoderma harzianum Rifai), powdery mildew pathogen (PPM-Golovinomyces orontii (Castagne) V.P. Heluta), and combined (PGPF+PPM) treatments. The findings of this study contribute to a better understanding of the role of cucumber CsLecRLK genes in response to PGPF, PPM, and PGPF+PPM treatments and lay the basis for the characterization of this important functional gene family.


Assuntos
Cucumis sativus/enzimologia , Erysiphe/imunologia , Imunidade Vegetal , Proteínas Quinases/genética , Estresse Fisiológico , Cromossomos de Plantas , Cucumis sativus/genética , Cucumis sativus/imunologia , Perfilação da Expressão Gênica , Genes de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo
9.
J Neurophysiol ; 119(5): 1934-1946, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442560

RESUMO

Multisite optical recording has revealed that the neural excitation wave induced by a sensory stimulation begins at a focus and propagates in the cortex. This wave is considered to be important for computation in the sensory cortex, particularly the integration of sensory information; however, the nature of this wave remains largely unknown. In the present study, we examined the interaction between two waves in the rat sensory cortex induced by hindlimb and forelimb stimuli with different interstimulus intervals. We classified the resultant patterns as follows: 1) the collision of two waves, 2) the hindlimb response being evoked while the forelimb-induced wave is passing the hindlimb focus, and 3) the hindlimb response being evoked after the forelimb-induced wave has passed the hindlimb focus. In pattern 1, the two waves fused into a single wave, but the propagation pattern differed from that predicted by the superimposition of two singly induced propagation courses. In pattern 2, the state of the interaction between the two waves varied depending on the phase of optical signals constituting the forelimb-induced wave around the hindlimb focus. Although no hindlimb-induced wave was observed in the rising phase, the propagating velocity of the forelimb-induced wave increased. At the peak, neither the hindlimb-induced response nor a modulatory effect on the forelimb-induced wave was detected. In pattern 3, the hindlimb-induced wave showed a reduced amplitude and spatial extent. These results indicate that the state of the interaction between waves was strongly influenced by the relative timing of sensory inputs. NEW & NOTEWORTHY Sensory stimulation-induced cortical excitation propagates as a wave and spreads over a wide area of the sensory cortex. To elucidate the characteristics of this relatively unknown phenomenon, we examined the interaction between two individually induced waves in the somatosensory cortex. Either the waves collided or the preceding wave affected the emergence of the following one. Our results indicate that the state of the interaction was strongly influenced by the relative timing of sensory inputs.


Assuntos
Ondas Encefálicas/fisiologia , Potenciais Evocados/fisiologia , Membro Anterior/fisiologia , Membro Posterior/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Estimulação Elétrica , Feminino , Imagem Óptica , Ratos , Ratos Sprague-Dawley , Análise Espaço-Temporal
10.
Z Naturforsch C J Biosci ; 74(1-2): 55-59, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30864389

RESUMO

A strain of Bacillus methylotrophicus was isolated from a soil sample collected in Aswan eastern desert, which is known for its extremely arid climate. After fermentation of the strain in liquid culture and subsequent extraction, a bioassay-guided isolation procedure yielded five compounds: 2-benzyl-4H-pyran-4-one, named bacillopyrone (1), pyrophen (2), macrolactin A (3) and the cyclopeptides malformin A1 (4), and bacillopeptin A (5). The structures were determined by interpretation of nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HR-MS) data. This is the first report on the isolation of compounds 1 and 2 from Bacillus species; compound 1 was reported previously as synthetic product. Bacillopyrone (1) exhibited moderate activity against the Gram-negative Chromobacterium violaceum with minimum inhibitory concentration 266.6 µg/mL, while macrolactin A (3) and malformin A1 (4) inhibited Staphylococcus aureus (minimum inhibitory concentrations 13.3 and 133.3 µg/mL, respectively).


Assuntos
Antibacterianos/metabolismo , Bacillus/metabolismo , Peptídeos Cíclicos/química , Pironas/química , Microbiologia do Solo , Antibacterianos/química , Bacillus/química , Bacillus/isolamento & purificação , Chromobacterium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Peptídeos Cíclicos/isolamento & purificação , Peptídeos Cíclicos/farmacologia , Fenilalanina/análogos & derivados , Fenilalanina/química , Fenilalanina/isolamento & purificação , Fenilalanina/farmacologia , Pironas/isolamento & purificação , Pironas/farmacologia , Staphylococcus aureus/efeitos dos fármacos
11.
J Am Chem Soc ; 139(39): 13761-13769, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28926230

RESUMO

Two-dimensional (2D) materials are promising for applications in a wide range of fields because of their unique properties. Hydrogen boride sheets, a new 2D material recently predicted from theory, exhibit intriguing electronic and mechanical properties as well as hydrogen storage capacity. Here, we report the experimental realization of 2D hydrogen boride sheets with an empirical formula of H1B1, produced by exfoliation and complete ion-exchange between protons and magnesium cations in magnesium diboride (MgB2) with an average yield of 42.3% at room temperature. The sheets feature an sp2-bonded boron planar structure without any long-range order. A hexagonal boron network with bridge hydrogens is suggested as the possible local structure, where the absence of long-range order was ascribed to the presence of three different anisotropic domains originating from the 2-fold symmetry of the hydrogen positions against the 6-fold symmetry of the boron networks, based on X-ray diffraction, X-ray atomic pair distribution functions, electron diffraction, transmission electron microscopy, photo absorption, core-level binding energy data, infrared absorption, electron energy loss spectroscopy, and density functional theory calculations. The established cation-exchange method for metal diboride opens new avenues for the mass production of several types of boron-based 2D materials by countercation selection and functionalization.

12.
Sci Technol Adv Mater ; 18(1): 857-869, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29152018

RESUMO

We propose a method to predict grain growth based on data assimilation by using a four-dimensional variational method (4DVar). When implemented on a multi-phase-field model, the proposed method allows us to calculate the predicted grain structures and uncertainties in them that depend on the quality and quantity of the observational data. We confirm through numerical tests involving synthetic data that the proposed method correctly reproduces the true phase-field assumed in advance. Furthermore, it successfully quantifies uncertainties in the predicted grain structures, where such uncertainty quantifications provide valuable information to optimize the experimental design.

13.
Phytopathology ; 105(4): 525-32, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25412011

RESUMO

Fusarium oxysporum f. sp. cepae causes Fusarium basal rot in onion (common onion) and Fusarium wilt in Welsh onion. Although these diseases have been detected in various areas in Japan, knowledge about the genetic and pathogenic variability of F. oxysporum f. sp. cepae is very limited. In this study, F. oxysporum f. sp. cepae was isolated from onion and Welsh onion grown in 12 locations in Japan, and a total of 55 F. oxysporum f. sp. cepae isolates (27 from onion and 28 from Welsh onion) were characterized based on their rDNA intergenic spacer (IGS) and translation elongation factor-1α (EF-1α) nucleotide sequences, vegetative compatibility groups (VCGs), and the presence of the SIX (secreted in xylem) homologs. Phylogenetic analysis of IGS sequences showed that these isolates were grouped into eight clades (A to H), and 20 onion isolates belonging to clade H were monophyletic and assigned to the same VCG. All the IGS-clade H isolates possessed homologs of SIX3, SIX5, and SIX7. The SIX3 homolog was located on a 4 Mb-sized chromosome in the IGS-clade H isolates. Pathogenicity tests using onion seedlings showed that all the isolates with high virulence were in the IGS-clade H. These results suggest that F. oxysporum f. sp. cepae isolates belonging to the IGS-clade H are genetically and pathogenically different from those belonging to the other IGS clades.


Assuntos
Fusarium/genética , Cebolas/microbiologia , Doenças das Plantas/microbiologia , Sequência de Bases , Mapeamento Cromossômico , Primers do DNA/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fusarium/isolamento & purificação , Fusarium/patogenicidade , Marcadores Genéticos/genética , Japão , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Raízes de Plantas/microbiologia , Plântula/genética , Análise de Sequência de DNA , Virulência/genética
14.
Biosci Biotechnol Biochem ; 78(7): 1112-22, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25229844

RESUMO

To investigate the involvement of Allium roylei metabolites in the plant's defenses, a comprehensive analysis of the content of cysteine sulfoxides, flavonols, polyphenols, ascorbic acid, and saponins was carried out in the various organs of this species. Metabolomics high performance liquid chromatography (HPLC), spectral-based analysis, and histochemcial studies have given important insight to the validity of saponins as a key component involved in plant protection. The root-basal stem, bulb, and leaf extracts exhibited 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity with inhibition concentration (IC(50)) ranging from 0.649 to 0.757 mg/mL. The antimicrobial properties of the saponin and flavonoid crude extracts were evaluated. The saponin extracts demonstrated significant antifungal activity depending on the applied concentration, and the growth inhibition rate of the tested fungal pathogens ranged from 1.07 to 47.76%. No appreciable antibacterial activity was recorded in the same sample.


Assuntos
Allium/metabolismo , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Ácido Ascórbico/metabolismo , Transporte Biológico , Flavonoides/metabolismo , Flavonoides/farmacologia , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Especificidade de Órgãos , Polifenóis/metabolismo , Saponinas/metabolismo , Saponinas/farmacologia , Sulfóxidos/metabolismo
15.
Pathogens ; 13(7)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39057818

RESUMO

Here, 12 Fusarium strains, previously described as F. oxysporum f. sp. cepae (Foc), were examined via multi-locus sequencing of calmodulin (cmdA), RNA polymerase II second largest subunit (rpb2), and translation elongation factor 1-alpha (tef1), to verify the taxonomic position of Foc in the newly established epitype of F. oxysporum. The strains in this study were divided into two clades: F. nirenbergiae and Fusarium sp. To further determine the host specifications of the strains, inoculation tests were performed on onion bulbs and Welsh onion seedlings as potential hosts. Four strains (AC145, AP117, Ru-13, and TA) isolated from diseased onions commonly possessed the secreted in xylem (SIX)-3, 5, 7, 9, 10, 12, and 14 genes and were pathogenic and highly aggressive to onion bulbs, whereas all strains except for one strain (AF97) caused significant inhibition of Welsh onion growth. The inoculation test also revealed that the strains harboring the SIX9 gene were highly aggressive to both onion and Welsh onion and the gene was expressed during infection of both onions and Welsh onions, suggesting the important role of the SIX9 gene in pathogenicity. This study provides insights into the evolutionary pathogenicity differentiation of Fusarium strains causing Fusarium basal rot and wilt diseases in Allium species.

16.
J Pestic Sci ; 49(1): 52-57, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38450088

RESUMO

Flusulfamide inhibits germination of Plasmodiophora brassicae resting spores to suppress clubroot disease, but its mechanism of action on the germination of P. brassicae resting spores remains unclear. In this study, P. brassicae resting spores were treated with flusulfamide and visualized using transmission electron microscopy (TEM). The gene expression of P. brassicae resting spores was analyzed using RT-PCR, followed by immunoblotting analysis. TEM results revealed that flusulfamide suppressed the primary zoosporogenesis of P. brassicae resting spores during the early phase, and RT-PCR results revealed that flusulfamide affected the gene expression during the germination of the resting spores. Immunoblot and RT-qPCR analyses revealed that PbCyp3, an immunophilin (peptidyl-prolyl-isomerase) gene, was highly expressed, resulting in the unusual accumulation of PbCYP3 protein in P. brassicae resting spores immediately after treatment with flusulfamide. This suggests that flusulfamide may cause aberrant folding of proteins involved in primary zoosporogenesis, thereby inhibiting germination.

17.
Microorganisms ; 11(12)2023 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-38138005

RESUMO

Fusarium oxysporum f. sp. cepae (Foc) causes basal rot disease in Allium species, including onions (Allium cepa L.) and shallots (A. cepa L. Aggregatum group). Among Allium species, shallots can be crossbred with onions and are relatively more resistant to Foc than onions. Thus, shallots are considered a potential disease-resistant resource for onions. However, the mechanisms underlying the molecular interactions between shallots and Foc remain unclear. This study demonstrated that SIX5, an effector derived from Foc (FocSIX5), acts as an avirulence effector in shallots. We achieved this by generating a FocSIX5 gene knockout mutant in Foc, for which experiments which revealed that it caused more severe wilt symptoms in Foc-resistant shallots than the wild-type Foc and FocSIX5 gene complementation mutants. Moreover, we demonstrated that a single amino acid substitution (R67K) in FocSIX5 was insufficient to overcome shallot resistance to Foc.

18.
J Fungi (Basel) ; 9(4)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37108886

RESUMO

Pearl millet [Pennisetum glaucum (L.) R. Br.] is the essential food crop for over ninety million people living in drier parts of India and South Africa. Pearl millet crop production is harshly hindered by numerous biotic stresses. Sclerospora graminicola causes downy mildew disease in pearl millet. Effectors are the proteins secreted by several fungi and bacteria that manipulate the host cell structure and function. This current study aims to identify genes encoding effector proteins from the S. graminicola genome and validate them through molecular techniques. In silico analyses were employed for candidate effector prediction. A total of 845 secretory transmembrane proteins were predicted, out of which 35 proteins carrying LxLFLAK (Leucine-any amino acid-Phenylalanine-Leucine-Alanine-Lysine) motif were crinkler, 52 RxLR (Arginine, any amino acid, Leucine, Arginine), and 17 RxLR-dEER putative effector proteins. Gene validation analysis of 17 RxLR-dEER effector protein-producing genes was carried out, of which 5genes were amplified on the gel. These novel gene sequences were submitted to NCBI. This study is the first report on the identification and characterization of effector genes in Sclerospora graminicola. This dataset will aid in the integration of effector classes that act independently, paving the way to investigate how pearl millet responds to effector protein interactions. These results will assist in identifying functional effector proteins involving the omic approach using newer bioinformatics tools to protect pearl millet plants against downy mildew stress. Considered together, the identified effector protein-encoding functional genes can be utilized in screening oomycetes downy mildew diseases in other crops across the globe.

19.
Genome ; 55(11): 797-807, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23199574

RESUMO

This study was carried out to evaluate the antifungal effect of Allium cepa Aggregatum group (shallot) metabolites on Fusarium oxysporum and to determine the shallot chromosome(s) related to Fusarium wilt resistance using a complete set of eight Allium fistulosum - shallot monosomic addition lines. The antifungal effects of hexane, butanol, and water extraction fractions from bulbs of shallot on 35 isolates of F. oxysporum were examined using the disc diffusion method. Only hexane and butanol fractions showed high antifungal activity. Shallot showed no symptom of disease after inoculation with F. oxysporum f. sp. cepae. The phenolic content of the roots and the saponin content of root exudates of inoculated shallot increased to much higher levels than those of the control at 3 days after inoculation. Application of freeze-dried shallot root exudates to seeds of A. fistulosum soaked in a spore suspension of F. oxysporum resulted in protection of seedlings against infection. Among eight monosomic addition lines and A. fistulosum, FF+2A showed the highest resistance to Fusarium wilt. This monosomic addition line also showed a specific saponin band derived from shallot on the thin layer chromatography profile of saponins in the eight monosomic addition lines. The chromosome 2A of shallot might possess some of the genes related to Fusarium wilt resistance.


Assuntos
Allium/química , Allium/genética , Cromossomos de Plantas/genética , Fusarium/efeitos dos fármacos , Doenças das Plantas/imunologia , Extratos Vegetais/farmacologia , Allium/imunologia , Allium/microbiologia , Cromatografia em Camada Fina , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Fusarium/patogenicidade , Micélio , Fenóis/análise , Fenóis/isolamento & purificação , Fenóis/farmacologia , Doenças das Plantas/microbiologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Exsudatos de Plantas/química , Exsudatos de Plantas/isolamento & purificação , Exsudatos de Plantas/farmacologia , Raízes de Plantas/química , Raízes de Plantas/genética , Raízes de Plantas/imunologia , Raízes de Plantas/microbiologia , Saponinas/análise , Saponinas/isolamento & purificação , Saponinas/farmacologia , Plântula/química , Plântula/genética , Plântula/imunologia , Plântula/microbiologia , Sementes/química , Sementes/genética , Sementes/imunologia , Sementes/microbiologia , Esporos Fúngicos
20.
Pathogens ; 11(12)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36558767

RESUMO

Fusarium oxysporum f. sp. radicis-lycopersici (Forl) causes crown and root rot disease in tomato, effecting severe economic losses. However, research on the pathogenicity genes and infection strategy of Forl is limited compared to that on F. oxysporum f. sp. lycopersici (Fol). In this study, we characterized FoMC69 gene in Forl as a homolog of MC69 required for pathogenicity in rice blast pathogen-Magnaporthe oryzae. Gene expression analysis revealed that FoMC69 expressionin Forl is higher than that in Folin planta. FoMC69-knockout mutant of Forl had significantly reduced root rot symptoms compared to the wild-type strain, and full pathogenicity was restored by complementation. By contrast, ΔFoMC69 mutant of Fol presented the same symptoms as the wild type, suggesting that FoMC69 of Forl, but not of Fol, was essential for full virulence in tomato plants. Morphological differences between the Forl and ΔFoMC69 in the roots were observed by fluorescent labeling using WGA-FITC. Chlamydospores of the ΔFoMC69 mutant of Forlcontinuously increased during infection and were three times higher than that of the wild type at 21 days post-inoculation. These observations suggest that FoMC69 of Forl is required for virulence to tomato plants by involving the normal development and germination of chlamydospores.

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