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1.
Pol J Microbiol ; 70(3): 359-372, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34584530

RESUMO

Latent pathogenic fungi (LPFs) affect plant growth, but some of them may stably colonize plants. LPFs were isolated from healthy Houttuynia cordata rhizomes to reveal this mechanism and identified as Ilyonectria liriodendri, an unidentified fungal sp., and Penicillium citrinum. Sterile H. cordata seedlings were cultivated in sterile or non-sterile soils and inoculated with the LPFs, followed by the plants' analysis. The in vitro antifungal activity of H. cordata rhizome crude extracts on LPF were determined. The effect of inoculation of sterile seedlings by LPFs on the concentrations of rhizome phenolics was evaluated. The rates of in vitro growth inhibition amongst LPFs were determined. The LPFs had a strong negative effect on H. cordata in sterile soil; microbiota in non-sterile soil eliminated such influence. There was an interactive inhibition among LPFs; the secondary metabolites also regulated their colonization in H. cordata rhizomes. LPFs changed the accumulation of phenolics in H. cordata. The results provide that colonization of LPFs in rhizomes was regulated by the colonizing microbiota of H. cordata, the secondary metabolites in the H. cordata rhizomes, and the mutual inhibition and competition between the different latent pathogens.


Assuntos
Fungos , Houttuynia , Interações Microbianas , Extratos Vegetais , Plantas Medicinais , Rizoma , Fungos/efeitos dos fármacos , Houttuynia/microbiologia , Interações Microbianas/fisiologia , Extratos Vegetais/farmacologia , Plantas Medicinais/microbiologia , Rizoma/química , Rizoma/microbiologia , Microbiologia do Solo
2.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073251

RESUMO

Living organisms interact with each other during their lifetime, leading to genomes rearrangement and sequences transfer. These well-known phenomena give these organisms mosaic genomes, which challenge their classification. Moreover, many findings occurred between the IXXth and XXIst century, especially the discovery of giant viruses and candidate phyla radiation (CPR). Here, we tried to provide an updated classification, which integrates 216 representative genomes of the current described organisms. The reclassification was expressed through a genetic network based on the total genomic content, not on a single gene to represent the tree of life. This rhizomal exploration represents, more accurately, the evolutionary relationships among the studied species. Our analyses show a separated branch named fifth TRUC (Things Resisting Uncompleted Classifications). This taxon groups CPRs together, independently from Bacteria, Archaea (which regrouped also Nanoarchaeota and Asgard members), Eukarya, and the giant viruses (recognized recently as fourth TRUC). Finally, the broadening of analysis methods will lead to the discovery of new organisms, which justify the importance of updating the classification at every opportunity. In this perspective, our pragmatic representation could be adjusted along with the progress of evolutionary studies.


Assuntos
Archaea/classificação , Bactérias/classificação , Rizoma , Microbiologia do Solo , Vírus/classificação , Rizoma/microbiologia , Rizoma/virologia
3.
Sci Rep ; 11(1): 6092, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731746

RESUMO

The individual role of biochar, compost and PGPR has been widely studied in increasing the productivity of plants by inducing resistance against phyto-pathogens. However, the knowledge on combined effect of biochar and PGPR on plant health and management of foliar pathogens is still at juvenile stage. The effect of green waste biochar (GWB) and wood biochar (WB), together with compost (Comp) and plant growth promoting rhizobacteria (PGPR; Bacillus subtilis) was examined on tomato (Solanum lycopersicum L.) physiology and Alternaria solani development both in vivo and in vitro. Tomato plants were raised in potting mixture modified with only compost (Comp) at application rate of 20% (v/v), and along with WB and GWB at application rate of 3 and 6% (v/v), each separately, in combination with or without B. subtilis. In comparison with WB amended soil substrate, percentage disease index was significantly reduced in GWB amended treatments (Comp + 6%GWB and Comp + 3%GWB; 48.21 and 35.6%, respectively). Whereas, in the presence of B. subtilis disease suppression was also maximum (up to 80%) in the substrate containing GWB. Tomato plant growth and physiological parameters were significantly higher in treatment containing GWB (6%) alone as well as in combination with PGPR. Alternaria solani mycelial growth inhibition was less than 50% in comp, WB and GWB amended growth media, whereas B. subtilis induced maximum inhibition (55.75%). Conclusively, the variable impact of WB, GWB and subsequently their concentrations in the soil substrate was evident on early blight development and plant physiology. To our knowledge, this is the first report implying biochar in synergism with PGPR to hinder the early blight development in tomatoes.


Assuntos
Alternaria/crescimento & desenvolvimento , Bacillus subtilis/crescimento & desenvolvimento , Carvão Vegetal/farmacologia , Compostagem , Lycopersicon esculentum/microbiologia , Doenças das Plantas/microbiologia , Rizoma/microbiologia , Lycopersicon esculentum/crescimento & desenvolvimento
4.
PLoS One ; 16(2): e0246687, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33556120

RESUMO

Compared with root-associated habitats, little is known about the role of microbiota inside other rice organs, especially the rhizome of perennial wild rice, and this information may be of importance for agriculture. Oryza longistaminata is perennial wild rice with various agronomically valuable traits, including large biomass on poor soils, high nitrogen use efficiency, and resistance to insect pests and disease. Here, we compared the endophytic bacterial and archaeal communities and network structures of the rhizome to other compartments of O. longistaminata using 16S rRNA gene sequencing. Diverse microbiota and significant variation in community structure were identified among different compartments of O. longistaminata. The rhizome microbial community showed low taxonomic and phylogenetic diversity as well as the lowest network complexity among four compartments. Rhizomes exhibited less phylogenetic clustering than roots and leaves, but similar phylogenetic clustering with stems. Streptococcus, Bacillus, and Methylobacteriaceae were the major genera in the rhizome. ASVs belonging to the Enhydrobacter, YS2, and Roseburia are specifically present in the rhizome. The relative abundance of Methylobacteriaceae in the rhizome and stem was significantly higher than that in leaf and root. Noteworthy type II methanotrophs were observed across all compartments, including the dominant Methylobacteriaceae, which potentially benefits the host by facilitating CH4-dependent N2 fixation under nitrogen nutrient-poor conditions. Our data offers a robust knowledge of host and microbiome interactions across various compartments and lends guidelines to the investigation of adaptation mechanisms of O. longistaminata in nutrient-poor environments for biofertilizer development in agriculture.


Assuntos
Oryza/microbiologia , Rizoma/microbiologia , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Perfilação da Expressão Gênica/métodos , Microbiota/genética , Oryza/genética , Oryza/metabolismo , Filogenia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Rizoma/genética , Rizoma/metabolismo
5.
Sci Rep ; 11(1): 1574, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452327

RESUMO

The plant microbiota play a key role in plant productivity, nutrient uptake, resistance to stress and flowering. The flowering of moso bamboo has been a focus of study. The mechanism of flowering is related to nutrient uptake, temperature, hormone balance and regulation of key genes. However, the connection between microbiota of moso bamboo and its flowering is unknown. In this study, samples of rhizosphere soil, rhizomes, roots and leaves of flowering and nonflowering plants were collected, and 16S rRNA amplicon Illumina sequencing was utilized to separate the bacterial communities associated with different flowering stages of moso bamboo. We identified 5442 OTUs, and the number of rhizosphere soil OTUs was much higher than those of other samples. Principal component analysis (PCA) and hierarchical clustering (Bray Curtis dis) analysis revealed that the bacterial microorganisms related to rhizosphere soil and endophytic tissues of moso bamboo differed significantly from those in bulk soil and rhizobacterial and endosphere microbiomes. In addition, the PCA analyses of root and rhizosphere soil revealed different structures of microbial communities between bamboo that is flowering and not flowering. Through the analysis of core microorganisms, it was found that Flavobacterium, Bacillus and Stenotrophomonas played an important role in the absorption of N elements, which may affect the flowering time of moso bamboo. Our results delineate the complex host-microbe interactions of this plant. We also discuss the potential influence of bacterial microbiome in flowering, which can provide a basis for the development and utilization of moso bamboo.


Assuntos
Rizoma/microbiologia , Sasa/microbiologia , Bacillus/genética , Bacillus/metabolismo , Bactérias/genética , Bactérias/metabolismo , Flavobacterium/genética , Flavobacterium/metabolismo , Flores/genética , Flores/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Microbiota/genética , Nutrientes/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Poaceae/genética , Poaceae/microbiologia , RNA Ribossômico 16S/genética , Rizosfera , Sasa/genética , Solo/química , Microbiologia do Solo , Stenotrophomonas/genética , Stenotrophomonas/metabolismo
6.
Probiotics Antimicrob Proteins ; 13(1): 32-39, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32537712

RESUMO

Pitchers are the unique structures of carnivorous plants used for the trapping of insects and other small invertebrates. The digestion of captured prey here is assisted by the bacteria, which have been associated with pitchers. These bacterial communities can therefore expect to have a variety of plant beneficial functions. In this study, the bacterial isolate NhPBG1 from the pitcher of Nepenthes hamblack was screened for activity against Pythium aphanidermatum, Rhizoctonia solani, Fusarium oxysporum, and Colletotrichum accutatum and was found to have the inhibitory activity towards all the tested phytopathogens. Interestingly, the isolate was found to have hyper-inhibitory effect against P. aphanidermatum. Further to this, the isolate was also shown to be positive for plant beneficial traits such as indole-3-acetic acid (IAA) and ammonia production, phosphate, potassium and zinc solubilization, nitrogen fixation, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. BLAST analysis of the 16S rDNA sequence of NhPBG1 has identified it as Paraburkholderia sp. Also, the Zingiber officinale rhizome pre-treated with NhPBG1 was found to get protected from P. aphanidermatum induced infection, whereas the control showed symptoms of infection. This was further confirmed by the microscopic evaluation of the presence of fungal mycelia in the tissues of control. However, the mycelial invasion could not be detected in the NhPBG1 treated rhizome. The metabolite profiling of NhPBG1 by GC-MS has identified variety of general metabolites, while the antifungal compounds pyocyanin and 1-hydroxyphenazine could be identified by the LC-MS/MS analysis.


Assuntos
Antifúngicos , Agentes de Controle Biológico , Burkholderiaceae/isolamento & purificação , Fungos/crescimento & desenvolvimento , Gengibre/microbiologia , Rizoma/microbiologia , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Agentes de Controle Biológico/isolamento & purificação , Agentes de Controle Biológico/farmacologia
7.
Methods Mol Biol ; 2232: 23-29, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33161535

RESUMO

The microbiome is known to influence plant fitness and differs significantly between plant compartments. To characterize the communities associated with different plant compartments, it is necessary to separate plant tissues in a manner that is suitable for microbiome analysis. Here, we describe a standardized protocol for sampling the microbiomes associated with bulk soil, the apical and basal ectorhizosphere, the apical and ectorhizosphere, the rhizome, pseudostem, and leaves of Musa spp. The approach can easily be modified for work with other plants.


Assuntos
Microbiota/genética , Biologia Molecular/métodos , Folhas de Planta/microbiologia , Rizoma/genética , Musa/genética , Musa/microbiologia , Folhas de Planta/genética , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Rizoma/microbiologia
8.
PLoS One ; 15(12): e0241057, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33351824

RESUMO

By assessing diversity variations of bacterial communities under different rhizocompartment types (i.e., roots, rhizosphere soil, root zone soil, and inter-shrub bulk soil), we explore the structural difference of bacterial communities in different root microenvironments under desert leguminous plant shrubs. Results will enable the influence of niche differentiation of plant roots and root soil on the structural stability of bacterial communities under three desert leguminous plant shrubs to be examined. High-throughput 16S rRNA genome sequencing was used to characterize diversity and structural differences of bacterial microbes in the rhizocompartments of three xeric leguminous plants. Results from this study confirm previous findings relating to niche differentiation in rhizocompartments under related shrubs, and they demonstrate that diversity and structural composition of bacterial communities have significant hierarchical differences across four rhizocompartment types under leguminous plant shrubs. Desert leguminous plants showed significant hierarchical filtration and enrichment of the specific bacterial microbiome across different rhizocompartments (P < 0.05). The dominant bacterial microbiome responsible for the differences in microbial community structure and composition across different niches of desert leguminous plants mainly consisted of Proteobacteria, Actinobacteria, and Bacteroidetes. All soil factors of rhizosphere and root zone soils, except for NO3-N and TP under C. microphylla and the two Hedysarum spp., recorded significant differences (P < 0.05). Moreover, soil physicochemical factors have a significant impact on driving the differentiation of bacterial communities under desert leguminous plant shrubs. By investigating the influence of niches on the structural difference of soil bacterial communities with the differentiation of rhizocompartments under desert leguminous plant shrubs, we provide data support for the identification of dominant bacteria and future preparation of inocula, and provide a foundation for further study of the host plants-microbial interactions.


Assuntos
Fabaceae/microbiologia , Microbiota/genética , Rizosfera , Biodiversidade , Caragana/microbiologia , China , Biologia Computacional , Clima Desértico , Genoma Bacteriano , Interações entre Hospedeiro e Microrganismos/genética , Raízes de Plantas/microbiologia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rizoma/microbiologia , Microbiologia do Solo
9.
BMC Microbiol ; 20(1): 291, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32957914

RESUMO

BACKGROUND: The dried roots and rhizomes of medicinal licorices are widely used worldwide as a traditional medicinal herb, which are mainly attributed to a variety of bioactive compounds that can be extracted from licorice root. Endophytes and plants form a symbiotic relationship, which is an important source of host secondary metabolites. RESULTS: In this study, we used high-throughput sequencing technology and high-performance liquid chromatography to explore the composition and structure of the endophytic bacterial community and the content of bioactive compounds (glycyrrhizic acid, liquiritin and total flavonoids) in different species of medicinal licorices (Glycyrrhiza uralensis, Glycyrrhiza glabra, and Glycyrrhiza inflata) and in different planting years (1-3 years). Our results showed that the contents of the bioactive compounds in the roots of medicinal licorices were not affected by the species, but were significantly affected by the main effect growing year (1-3) (P < 0.05), and with a trend of stable increase in the contents observed with each growing year. In 27 samples, a total of 1,979,531 effective sequences were obtained after quality control, and 2432 effective operational taxonomic units (OTUs) were obtained at 97% identity. The phylum Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes, and the genera unified-Rhizobiaceae, Pseudomonas, Novosphingobium, and Pantoea were significantly dominant in the 27 samples. Distance-based redundancy analysis (db-RDA) showed that the content of total flavonoids explained the differences in composition and distribution of endophytic bacterial communities in roots of cultivated medicinal liquorices to the greatest extent. Total soil salt was the most important factor that significantly affected the endophytic bacterial community in soil factors, followed by ammonium nitrogen and nitrate nitrogen. Among the leaf nutrition factors, leaf water content had the most significant effect on the endophytic bacterial community, followed by total phosphorus and total potassium. CONCLUSIONS: This study not only provides information on the composition and distribution of endophytic bacteria in the roots of medicinal licorices, but also reveals the influence of abiotic factors on the community of endophytic bacteria and bioactive compounds, which provides a reference for improving the quality of licorice.


Assuntos
Flavonoides/biossíntese , Glycyrrhiza uralensis/microbiologia , Glycyrrhiza/microbiologia , Raízes de Plantas/microbiologia , Rizoma/microbiologia , Actinobacteria/classificação , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Amônia/farmacologia , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Código de Barras de DNA Taxonômico , DNA Bacteriano/genética , Endófitos/fisiologia , Firmicutes/classificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Flavanonas/biossíntese , Flavanonas/isolamento & purificação , Flavonoides/classificação , Flavonoides/isolamento & purificação , Glucosídeos/biossíntese , Glucosídeos/isolamento & purificação , Glycyrrhiza/efeitos dos fármacos , Glycyrrhiza/metabolismo , Glycyrrhiza uralensis/efeitos dos fármacos , Glycyrrhiza uralensis/metabolismo , Ácido Glicirrízico/isolamento & purificação , Ácido Glicirrízico/metabolismo , Consórcios Microbianos/efeitos dos fármacos , Consórcios Microbianos/genética , Nitratos/farmacologia , Filogenia , Raízes de Plantas/metabolismo , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Rhizobiaceae/classificação , Rhizobiaceae/genética , Rhizobiaceae/isolamento & purificação , Rizoma/metabolismo , Estações do Ano , Metabolismo Secundário , Solo/química , Microbiologia do Solo , Simbiose
10.
Fitoterapia ; 146: 104711, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32860875

RESUMO

Penctrimertone (1), a novel citrinin dimer bearing a 6/6/6/6 tetracyclic ring scaffold, along with two known compounds xerucitrinic acid A (2) and citrinin (3) were isolated from the endophytic fungus Penicillium sp. T2-11. Their structures were unequivocally established by a comprehensive interpretation of the spectroscopic data, with the stereochemistry for 1 was defined by a combination of TDDFT-ECD calculations and the DP4+ probability analysis based on NMR chemical shift calculations. Bioassays revealed that compound 1 exhibited noticeable antimicrobial activities and moderate cytotoxicity. A plausible biosynthetic pathway of 1 was also proposed.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Citrinina/farmacologia , Gastrodia/microbiologia , Penicillium/química , Antibacterianos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Linhagem Celular Tumoral , Queixo , Citrinina/isolamento & purificação , Endófitos/química , Humanos , Estrutura Molecular , Rizoma/microbiologia
11.
World J Microbiol Biotechnol ; 36(5): 77, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32399738

RESUMO

Protease mediated proteolysis has been widely implicated in virulence of necrotrophic fungal pathogens. This is counteracted in plants by evolving new and effective antimicrobial peptides (AMP) that constitute important components of innate immune system. Peptide extraction from rhizome of Zingiber zerumbet was optimized using ammonium sulphate (50-80% w/v) and acetone (60 and 100% v/v) with maximal protein recovery of 1.2 ± 0.4 mg/g obtained using 100% acetone. Evaluation of inhibitory potential of Z. zerumbet rhizome protein extract to prominent hydrolases of necrotrophic Pythium myriotylum revealed maximal inhibition of proteases (75.8%) compared to other hydrolytic enzymes. Protein was purified by Sephacryl S200HR resin resulting in twofold purification and protease inhibition of 84.4%. Non-reducing polyacrylamide gel electrophoresis (PAGE) of the fractions yielded two bands of 75 kDa and 25 kDa molecular size. Peptide mass fingerprint of the protein bands using matrix assisted laser desorption/ionization (MALDI)-time of flight (TOF) mass spectroscopy (MS) and subsequent MASCOT searches revealed peptide match to methylesterase from Arabidopsis thaliana (15%) and to hypothetical protein from Oryza sativa (98%) respectively. Further centrifugal filter purification using Amicon Ultra (10,000 MW cut-off) filter, yielded a prominent band of 25 kDa size. Concentration dependent inhibition of zoospore viability by Z. zerumbet AMP designated as ZzAMP was observed with maximal inhibition of 89.5% at 4 µg protein and an IC50 value of 0.59 µg. Studies are of particular relevance in the context of identifying the molecules involved in imparting below ground defense in Z. zerumbet as well in development of AMPs as potential candidate molecules for control of necrotrophic pathogens of agricultural relevance.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeo Hidrolases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pythium/efeitos dos fármacos , Rizoma/microbiologia , Zingiberaceae/microbiologia , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Arabidopsis , Inibidores Enzimáticos , Fungos/efeitos dos fármacos , Oryza , Peptídeos/farmacologia , Extratos Vegetais/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Zingiberaceae/crescimento & desenvolvimento
12.
BMC Plant Biol ; 20(1): 220, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32423383

RESUMO

BACKGROUND: Nitrogen is an essential element for sugarcane growth and development and is generally applied in the form of urea often much more than at recommended rates, causing serious soil degradation, particularly soil acidification, as well as groundwater and air pollution. In spite of the importance of nitrogen for plant growth, fewer reports are available to understand the application and biological role of N2 fixing bacteria to improve N2 nutrition in the sugarcane plant. RESULTS: In this study, a total of 350 different bacterial strains were isolated from rhizospheric soil samples of the sugarcane plants. Out of these, 22 isolates were selected based on plant growth promotion traits, biocontrol, and nitrogenase activity. The presence and activity of the nifH gene and the ability of nitrogen-fixation proved that all 22 selected strains have the ability to fix nitrogen. These strains were used to perform 16S rRNA and rpoB genes for their identification. The resulted amplicons were sequenced and phylogenetic analysis was constructed. Among the screened strains for nitrogen fixation, CY5 (Bacillus megaterium) and CA1 (Bacillus mycoides) were the most prominent. These two strains were examined for functional diversity using Biolog phenotyping, which confirmed the consumption of diverse carbon and nitrogen sources and tolerance to low pH and osmotic stress. The inoculated bacterial strains colonized the sugarcane rhizosphere successfully and were mostly located in root and leaf. The expression of the nifH gene in both sugarcane varieties (GT11 and GXB9) inoculated with CY5 and CA1 was confirmed. The gene expression studies showed enhanced expression of genes of various enzymes such as catalase, phenylalanine-ammonia-lyase, superoxide dismutase, chitinase and glucanase in bacterial-inoculated sugarcane plants. CONCLUSION: The results showed that a substantial number of Bacillus isolates have N-fixation and biocontrol property against two sugarcane pathogens Sporisorium scitamineum and Ceratocystis paradoxa. The increased activity of genes controlling free radical metabolism may at least in part accounts for the increased tolerance to pathogens. Nitrogen-fixation was confirmed in sugarcane inoculated with B. megaterium and B. mycoides strains using N-balance and 15N2 isotope dilution in different plant parts of sugarcane. This is the first report of Bacillus mycoides as a nitrogen-fixing rhizobacterium in sugarcane.


Assuntos
Interações entre Hospedeiro e Microrganismos , Microbiota , Fixação de Nitrogênio , Bactérias Fixadoras de Nitrogênio/metabolismo , Saccharum/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Bactérias Fixadoras de Nitrogênio/classificação , Bactérias Fixadoras de Nitrogênio/isolamento & purificação , Rizoma/crescimento & desenvolvimento , Rizoma/microbiologia , Saccharum/microbiologia
13.
Arch Microbiol ; 202(7): 1899-1906, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32448960

RESUMO

Endophytic bacteria have been reported to have symbiotic, mutualistic, commensalistic or trophobiotic relationships with various plant parts. As part of its adaptation, many endophytic organisms are known to exhibit properties with multiple beneficial effects to the plant system. Even though many bacterial genera have been identified to have endophytic association, isolation of those which were previously demonstrated well for human association is quite interesting. In the study, endophytic bacteria Ceb1 isolated from the rhizome of Curcuma longa was identified by 16S rDNA sequencing as Staphylococcus sp. Further, Ceb1 was observed to have the ability to tolerate drought stress. While screening for the plant growth-promoting traits, Ceb1 was found to be positive for IAA production both under drought-stressed and normal conditions as confirmed by HPLC. The Ceb1 priming with Vigna unguiculata was observed to enhance the growth parameters of the plant. Analysis of Ceb1-treated plants by ICP-MS further showed modulation of both macro- and micronutrients. Upon drought stress induction in Vigna unguiculata, Ceb1 was found to provide synergistic plant growth-promoting effect to the plant along with the supplemented silicate sources. Under the changing agroclimatic conditions, exploring the plant stress-alleviating effects of endophytes is highly significant.


Assuntos
Secas , Desenvolvimento Vegetal , Plantas/microbiologia , Silicatos/farmacologia , Staphylococcus/fisiologia , Curcuma/microbiologia , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Endófitos/metabolismo , Desenvolvimento Vegetal/fisiologia , RNA Ribossômico 16S/genética , Rizoma/microbiologia , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Simbiose , Vigna/fisiologia
14.
J Hazard Mater ; 390: 121806, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058900

RESUMO

An emerging stress of nanomaterials in soil and water is of great concern as it limits crop productivity and affects humans as well. Therefore, it is required to manage this problem. Silicon and plant growth promoting rhizobacteria has gained the engaging role in agriculture as (bio-)fertilizers. However, their role against silver nanoparticles (AgNPs) is still not known. Hence, present study was envisaged to investigate role of Si, PGPR and phytohormone indole acetic acid (IAA) in regulating AgNP stress in Brassica juncea seedlings. The study highlighted the impact of various treatments with respect to overproduction of reactive oxygen species, signaling molecule nitric oxide, oxidative markers like antioxidant enzymes and nonenzymatic components of ascorbate-glutathione pathway. Interestingly, silicon when present with AgNPs enhanced toxicity by reducing growth and mechanistic properties of B. juncea. Moreover, the results highlight the role of PGPR and IAA towards reduction in toxicity by promoting the plant growth under stressed conditions. Treatments AgNP + Si + PGPR/IAA were observed to significantly reduce the stress and enhance plant growth against treatment AgNPs alone. This reversal in toxicity by PGPR and IAA along with Si suggests the idea to formulate and utilize their combination as biofertilizers for eradicating the stress in near future.


Assuntos
Bacillus thuringiensis , Nanopartículas Metálicas/toxicidade , Mostardeira/efeitos dos fármacos , Óxido Nítrico/metabolismo , Rizoma/microbiologia , Silício/toxicidade , Prata/toxicidade , Ácido Ascórbico/metabolismo , Glutationa/metabolismo , Ácidos Indolacéticos/farmacologia , Mostardeira/crescimento & desenvolvimento , Mostardeira/microbiologia
15.
Fungal Biol ; 124(1): 24-33, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31892374

RESUMO

Of the more than 400 indigenous orchid species in Western Australia, Cryptostylis ovata is the only species that retains its leaves all year round. It exists as a terrestrial herb and occasionally as an epiphyte in forested areas. Like all terrestrial orchids, C. ovata plants associate with mycorrhizal fungi, but their identities have not previously been investigated. Fungi were isolated from pelotons in rhizomes collected from three southern and two northern populations of C. ovata on six occasions over two years. Phylogenetic analysis of ITS sequences temporally and spatially revealed that all the fungal isolates were of Tulasnella species of four distinct groups. One Tulasnella group was present only in the three southern orchid populations, and it closely resembled T. prima isolates previously described from Chiloglottis sp. orchids from eastern Australia. Isolates collected from plants in the two northern populations were of three undescribed Tulasnella groups. Analysis of intra-group diversity using inter-simple sequence repeat markers revealed that plants were usually colonised by a single genotype of Tulasnella at each sampling period, and this genotype usually, but not always, persisted with the host plant over both years tested.


Assuntos
Basidiomycota/isolamento & purificação , Micorrizas/isolamento & purificação , Orchidaceae/microbiologia , Rizoma/microbiologia , Basidiomycota/classificação , Basidiomycota/genética , DNA Fúngico/genética , Variação Genética , Repetições de Microssatélites , Micorrizas/classificação , Micorrizas/genética , Filogenia , Simbiose , Austrália Ocidental
16.
Fitoterapia ; 140: 104422, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31756377

RESUMO

Peniterester (1), a new tricyclic sesquiterpene, together with 6 known compounds (2-7) were isolated from the secondary metabolites of an artificial mutant Penicillium sp. T2-M20 which was obtained from the parental strain Penicillium sp. T2-8 via UV irradiation as well as nitrosoguanidine (NTG) induction. Peniterester was only produced by the mutant T2-M20 on the basis of LC-MS analysis. Meanwhile, the results of in vitro bioactivities screening indicated that peniterester owned obvious antibacterial activities against Bacillus subtilis, Escherichia coli and Staphylococcus aureus with MICs of 8.0, 8.0 and 4.0 µg/mL, respectively.


Assuntos
Antibacterianos/farmacologia , Penicillium/química , Sesquiterpenos/farmacologia , Antibacterianos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Linhagem Celular Tumoral , China , Escherichia coli/efeitos dos fármacos , Gastrodia/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Rizoma/microbiologia , Metabolismo Secundário , Sesquiterpenos/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos
17.
J Med Food ; 22(10): 1067-1077, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31403348

RESUMO

To reduce microbial loads in medicinal herbs, Cnidii Rhizoma and Alismatis Rhizoma were subjected to electron-beam (e-beam) irradiation at doses (≤10 kGy) as permitted by the Korean Food Code. The effects of e-beam irradiation on the microbial load, stability of the active components, and anti-inflammatory activity of medicinal herbs were determined. We observed that the total aerobic bacteria (TAB; 4.0-7.0 log CFU/g), yeasts and molds (Y&M; 3.3-6.8 log CFU/g), and coliform counts (CC; 3.2-3.8 log CFU/g) in both herb samples were effectively reduced in a dose-dependent manner, resulting in acceptable levels of <3.0 log CFU/g in TAB and Y&M and negative in CC at 10 kGy irradiation. The concentration of the active components (0.87-4.22 mg/g) of Cnidii Rhizoma, including z-ligustilide, chlorogenic acid, senkyunolide A, and ferulic acid, in order of prevalence and those (0.86-2.76 mg/g) of Alismatis Rhizoma, including Alisol B acetate and Alisol B, were not changed at irradiation doses of ≤10 kGy. The extracts of e-beam irradiated Cnidii Rhizoma and Alismatis Rhizoma showed a reduced production of inflammation-related factors, such as nitric oxide, prostaglandin E2, interleukin (IL)-1ß, and IL-6, in a concentration-dependent manner, which was induced by lipopolysaccharide in RAW 264.7 cell. However, there was no significant difference observed at e-beam irradiation doses of 0, 1, 5, and 10 kGy. Thus, we confirm that e-beam irradiation up to 10 kGy was effective for the control of microbial load in Cnidii Rhizoma and Alismatis Rhizoma without causing considerable changes in their major active components and anti-inflammatory activity. The results show the potential of e-beam application for sanitization of medicinal herbs.


Assuntos
Alisma/química , Anti-Inflamatórios/química , Apiaceae/química , Carga Bacteriana , Rizoma/química , Alisma/microbiologia , Alisma/efeitos da radiação , Animais , Anti-Inflamatórios/farmacologia , Apiaceae/microbiologia , Apiaceae/efeitos da radiação , Dinoprostona/metabolismo , Elétrons , Interleucinas/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Plantas Medicinais/microbiologia , Plantas Medicinais/efeitos da radiação , Células RAW 264.7 , Rizoma/microbiologia , Rizoma/efeitos da radiação
18.
Plant Sci ; 286: 118-133, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300137

RESUMO

The rhizomicrobiome helps the host plant to better adapt to environmental stresses. In contrast, plant-derived metabolic substances, including phytohormones, play an active role in structuring rhizomicrobiome. Although strigolactones (SLs), a group of phytohormones, serve as potential rhizosphere signaling molecules, their contributions in shaping the rice (Oryza sativa) rhizomicrobiome remain elusive. To address this issue, we compared the rhizomicrobiome of rice mutants defective in either SL biosynthesis or signaling and wild-type (WT) plants. To understand whether SL-regulated metabolic pathways shape the rhizomicrobiome, a correlation network analysis was conducted among the metabolic pathway-related genes and the rhizomicrobiome of rice. Compared to WT, higher bacterial richness (evidenced by the operational taxonomic unit richness) and lower fungal diversity (evidenced by the Shannon index) were observed in both SL deficient dwarf17 (d17) and signaling (d14) mutants. Additionally, remarkable differences were observed in the composition of a large number of bacterial communities than the fungal communities in the d17 and d14 mutants with respect to the WT. The abundance of certain beneficial bacterial taxa, including Nitrosomonadaceae and Rhodanobacter, were significantly decreased in both mutants relative to the WT. Correlation network analysis between SL-regulated metabolic pathway-associated genes and rhizomicrobiome proposed a role for SL-dependent metabolic pathways in shaping rhizomicrobiome composition. Taken together, our study suggests that SL biosynthesis and signaling play a key role in determining the rice rhizomicrobiome, directly or indirectly, through the mediation of distinct metabolic pathways. Based on our findings, the genetic modulation of rice SL biosynthesis and/or signaling pathways may help to recruit/increase the abundance of the desired rhizomicrobiome, which may assist in the stress resilience of rice.


Assuntos
Lactonas/metabolismo , Microbiota , Oryza/metabolismo , Rizoma/microbiologia , Transdução de Sinais
19.
J Sci Food Agric ; 99(14): 6155-6166, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31206685

RESUMO

BACKGROUND: Rhizome rot, caused primarily by Fusarium oxysporum, is one of the most destructive diseases leading to significant loss in ginger worldwide. The loss can be greatly reduced by proper disease management practices steered by accurate and early diagnosis of pathogens. Pathogen detection at an early stage of infection can also reduce the incidence of disease epidemics. Classical methods are often time consuming, relying on culturing the putative pathogens and the availability of expert taxonomic skills for accurate identification, which leads to the delayed application of control measures. The development of a simple, rapid, sensitive and cost-effective point-of-care diagnostic tool is thus one of the major research priorities for rhizome rot. RESULTS: The 65 kDa, immunoreactive protein band was selected as a diagnostic marker and was subjected to MS analysis followed by blastp. Based on blast result, a synthetic antigenic peptide was synthesized, and used to generate pAbs. The peptide-specific antibodies were used to develop a colloidal gold immunochromatographic assay (ICA). The sensitivity, specificity, and accuracy of ICA were 92.59%, 81.25%, and 90%, respectively. The ICA has a visual detection limit of 2.122 µg mL-1 for infected rhizome samples and 5.065 µg mL-1 for leaf samples with optimal detection time within 5 min. Moreover, the ICA also detected early stage infected samples, of which 71.42% (50/70) were true positives. CONCLUSION: Findings from this study indicated that the assay can be utilized as a tool for the investigation of rhizome rot infection in field samples. © 2019 Society of Chemical Industry.


Assuntos
Fusarium/isolamento & purificação , Gengibre/microbiologia , Imunoensaio/métodos , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/imunologia , Fusarium/imunologia , Gengibre/química , Coloide de Ouro/química , Imunoensaio/instrumentação , Limite de Detecção , Rizoma/química , Rizoma/microbiologia , Sensibilidade e Especificidade
20.
Int J Syst Evol Microbiol ; 69(2): 454-459, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30556802

RESUMO

An endophytic actinobacterium, designated strain KE2-3T, was isolated from surface-sterilised rhizome of Kaempferia elegans. The polyphasic approach was used for evaluating the taxonomic position of this strain. The taxonomic affiliation of this strain at genus level could be confirmed by its chemotaxonomic characteristic, i.e. the presence of ll-diaminopimelic acid in the cell peptidoglycan, MK-9(H4) as the major menaquinone, iso-C16 : 0, anteiso-C15 : 0, iso-C14 : 0 and iso-C15 : 0 as the predominant fatty acids in cells, and the presence of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside in its membranes. Based on 16S rRNA gene sequence analysis, strain KE2-3T was identified as a member of the genus Jiangella and showed the highest similarities to Jiangella muralis DSM 45357T (99.3 %) followed by Jiangella albaDSM 45237T (99.2 %), Jiangella alkaliphilia DSM 45079T (99.0 %), Jiangella gansuensisDSM 44835T (98.8 %) and Jiangella mangrovi3SM4-07T (98.6 %). However, the draft genome sequence of strain KE2-3T exhibited low average nucleotide identity values to the reference strains (85.5-90.2 %), which were well below the 95-96 % species circumscription threshold. The DNA G+C content of genomic DNA was 72.3 mol%. With the differences of physiological, biochemical and genotypic data, strain KE2-3T could be discriminated from its closest neighbour. Thus, strain KE2-3T should be recognised as a novel species of genus Jiangella, for which the name Jiangellaendophytica sp. nov. is proposed. The type strain is KE2-3T (=BCC 66359T=NBRC 110004T).


Assuntos
Actinobacteria/classificação , Filogenia , Rizoma/microbiologia , Zingiberaceae/microbiologia , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Sequência de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tailândia , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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