Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 6.006
Filtrar
2.
Nat Commun ; 11(1): 4897, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32994415

RESUMO

Soil microbial respiration is an important source of uncertainty in projecting future climate and carbon (C) cycle feedbacks. However, its feedbacks to climate warming and underlying microbial mechanisms are still poorly understood. Here we show that the temperature sensitivity of soil microbial respiration (Q10) in a temperate grassland ecosystem persistently decreases by 12.0 ± 3.7% across 7 years of warming. Also, the shifts of microbial communities play critical roles in regulating thermal adaptation of soil respiration. Incorporating microbial functional gene abundance data into a microbially-enabled ecosystem model significantly improves the modeling performance of soil microbial respiration by 5-19%, and reduces model parametric uncertainty by 55-71%. In addition, modeling analyses show that the microbial thermal adaptation can lead to considerably less heterotrophic respiration (11.6 ± 7.5%), and hence less soil C loss. If such microbially mediated dampening effects occur generally across different spatial and temporal scales, the potential positive feedback of soil microbial respiration in response to climate warming may be less than previously predicted.


Assuntos
Carbono/análise , Metagenoma/genética , Microbiota/fisiologia , Microbiologia do Solo , Solo/química , Aclimatação/genética , Archaea/genética , Archaea/isolamento & purificação , Archaea/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Carbono/metabolismo , Ciclo do Carbono , Celulose/metabolismo , DNA Ambiental/genética , DNA Ambiental/isolamento & purificação , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Aquecimento Global , Pradaria , Temperatura Alta/efeitos adversos , Metagenômica , Modelos Genéticos , Raízes de Plantas/química , Poaceae/química
3.
Sci Total Environ ; 738: 140249, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806340

RESUMO

Environmental DNA (eDNA) metabarcoding and metagenomics analyses can improve taxonomic resolution in biodiversity studies. Only recently, these techniques have been applied in aerobiology, to target bacteria, fungi and plants in airborne samples. Here, we present a nine-month aerobiological study applying eDNA metabarcoding in which we analyzed simultaneously airborne diversity and variation of fungi and plants across five locations in North and Central Italy. We correlated species composition with the ecological characteristics of the sites and the seasons. The most abundant taxa among all sites and seasons were the fungal genera Cladosporium, Alternaria, and Epicoccum and the plant genera Brassica, Corylus, Cupressus and Linum, the latter being much more variable among sites. PERMANOVA and indicator species analyses showed that the plant diversity from air samples is significantly correlated with seasons, while that of fungi varied according to the interaction between seasons and sites. The results consolidate the performance of a new eDNA metabarcoding pipeline for the simultaneous amplification and analysis of airborne plant and fungal particles. They also highlight the promising complementarity of this approach with more traditional biomonitoring frameworks and routine reports of air quality provided by environmental agencies.


Assuntos
Código de Barras de DNA Taxonômico , DNA Ambiental , Fungos/genética , Itália , Estações do Ano
4.
PLoS One ; 15(8): e0237164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833980

RESUMO

Minor grain crops are widely cultivated in northwest China and played important roles in local economic. Soil microbes play a central role in ecological function and biological stability and related to soil quality. In order to uncover the soil microbial composition differences and the factors under 5-year continuous monocropping of three minor crops (Proso millet, Common bean and Common buckwheat) in Guan-Zhong Plain, six soil nutrimental parameters, soil pH, soil moisture content, and four soil enzyme activities were analyzed and soil microbial composition were sequenced. The results showed that after 5-years of continuous monocropping, different cover crops influenced most of soil physicochemical properties, expect soil moisture content (P < 0.05), the available nutrients were significant higher in proso millet soil, and the pH was significantly higher in common buckwheat soil. soil ALP, catalase and urease activities were significantly different between soils (P< 0.01), in which soil catalase activities were significantly lower and soil ALP and urease activities were significantly higher than that of proso millet and common buckwheat. A total of 171439 sequences, 9468 OTUs and 29 phylum for bacteria, 128920 sequences, 544 OTUs and 27 phylum for fungi were obtained. In addition, no significantly difference obtained in diversity and richness between soils (P < 0.05). According to relative abundance, Proteobacteria, Chloroflexi, Gemmatimonadetes and Acidobacteria were the dominant bacterial phylum in all samples, moreover, the relative abundance of Caldiserica was significantly different between soils (P < 0.05). Ascomycota (79.04%-90.21%) was dominant phylum in fungal community and phylum Phragmoplastophyta (P < 0.01) and Glomeromycota (P < 0.05) were significantly different between soils. Redundancy analysis indicated that available nutrients Nitrogen and Potassium are the strongest predictors in both bacterial and fungal community. In conclusion, different cover crops influenced soil nutrient properties, soil pH and soil microbial composition, and continuous monocropping decreased soil fertility condition. Moreover, Common bean and Common buckwheat were more sensitive to monocropping treatment.


Assuntos
Agricultura/métodos , Bactérias/genética , Produtos Agrícolas/microbiologia , Fungos/genética , Micobioma/genética , Microbiologia do Solo , Solo/química , China , Variação Genética , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Nutrientes/análise , Reação em Cadeia da Polimerase , Potássio/análise , RNA Ribossômico 16S/genética
5.
PLoS Genet ; 16(8): e1008996, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841242

RESUMO

The utilization of different carbon sources in filamentous fungi underlies a complex regulatory network governed by signaling events of different protein kinase pathways, including the high osmolarity glycerol (HOG) and protein kinase A (PKA) pathways. This work unraveled cross-talk events between these pathways in governing the utilization of preferred (glucose) and non-preferred (xylan, xylose) carbon sources in the reference fungus Aspergillus nidulans. An initial screening of a library of 103 non-essential protein kinase (NPK) deletion strains identified several mitogen-activated protein kinases (MAPKs) to be important for carbon catabolite repression (CCR). We selected the MAPKs Ste7, MpkB, and PbsA for further characterization and show that they are pivotal for HOG pathway activation, PKA activity, CCR via regulation of CreA cellular localization and protein accumulation, as well as for hydrolytic enzyme secretion. Protein-protein interaction studies show that Ste7, MpkB, and PbsA are part of the same protein complex that regulates CreA cellular localization in the presence of xylan and that this complex dissociates upon the addition of glucose, thus allowing CCR to proceed. Glycogen synthase kinase (GSK) A was also identified as part of this protein complex and shown to potentially phosphorylate two serine residues of the HOG MAPKK PbsA. This work shows that carbon source utilization is subject to cross-talk regulation by protein kinases of different signaling pathways. Furthermore, this study provides a model where the correct integration of PKA, HOG, and GSK signaling events are required for the utilization of different carbon sources.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/genética , Glucose/metabolismo , Quinases da Glicogênio Sintase/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Aspergillus nidulans/enzimologia , Repressão Catabólica/genética , Fungos/genética , Fungos/metabolismo , Glicerol/metabolismo , Concentração Osmolar , Fosforilação/genética , Mapas de Interação de Proteínas/genética , Proteínas Repressoras/genética , Xilose/metabolismo
6.
PLoS One ; 15(7): e0236936, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735609

RESUMO

The Roux-en-Y gastric bypass (RYGB) remains the most effective treatment for morbidly obese patients to lower body weight and improve glycemic control. There is recent evidence that the mycobiome (fungal microbiome) can aggravate disease severity in a number of diseases including inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) and hepatitis; moreover, a dysbiotic fungal microbiota has been reported in the obese. We characterized fungal and bacterial microbial composition in fecal samples of 16 morbidly obese patients before and three months after RYGB surgery and compared with nine healthy controls. We found that RYGB surgery induced a clear alteration in structure and composition of the gut fungal and bacterial microbiota. Beta diversity analysis revealed significant differences in bacterial microbiota between obese patients before surgery and healthy controls (P < 0.005) and a significant, unidirectional shift in RYGB patients after surgery (P < 0.001 vs. before surgery). In contrast, there was no significant difference in fungal microbiota between groups but individually specific changes after RYGB surgery. Interestingly, RYGB surgery induced a significant reduction in fungal alpha diversity namely Chao1, Sobs, and Shannon diversity index (P<0.05, respectively) which contrasts the trend for uniform changes in bacteria towards increased richness and diversity post-surgery. We did not observe any inter-kingdom relations in RYGB patients but in the healthy control cohort and there were several correlations between fungi and bacteria and clinical parameters (P<0.05, respectively) that warrant further research. Our study identifies changes in intestinal fungal communities in RYGB patients that are distinct to changes in the bacterial microbiota.


Assuntos
Derivação Gástrica , Microbioma Gastrointestinal , Obesidade Mórbida , Adulto , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , DNA Intergênico , Fezes/microbiologia , Feminino , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Genes Bacterianos , Genes Fúngicos , Humanos , Masculino , Metagenômica , Microbiota , Pessoa de Meia-Idade , Micobioma , Obesidade Mórbida/microbiologia , Obesidade Mórbida/cirurgia , Projetos Piloto , RNA Ribossômico 16S/genética
7.
PLoS One ; 15(8): e0237368, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32780777

RESUMO

Soil archives are an important resource in agronomic and ecosystem sciences. If microbial communities could be reconstructed from archived soil DNA, as prehistoric plant communities are reconstructed via pollen data, soil archive resources would assume even greater value for reconstructing land-use history, forensic science, and biosphere modelling. Yet, the effects of long-term soil archival on the preservation of microbial DNA is still largely unknown. To address this, we assessed the capacity of high-throughput sequencing (Illumina MiSeq) of ITS (internal transcribed spacer) and prokaryotic 16S rRNA genes for reconstructing soil microbial communities across a 20 years time-series. We studied air-dried soil archives and fresh soil samples taken from Populus bioenergy and deciduous forest research plots at the Kellogg Biological Station. Habitat and archival time explained significant amounts of variation in soil microbial α- and ß-diversity both in fungal and prokaryotic communities. We found that microbial richness, diversity, and abundance generally decreased with storage time, but varied between habitat and taxonomic groups. The high relative abundance of ectomycorrhizal species including Hebeloma and Cortinarius detected in older soil archives raises questions regarding traits such as long-term persistence and viability of ectomycorrhizal propagules in soils, with relevance to forest health and ecosystem succession. Talaromyces, Paecilomyces and Epicoccum spp. were detected in fresh and across 20-year-old archived soils and were also cultured from these soils demonstrating their long-term spore viability. In summary, we found that microbial DNA in air-dried soils archived over the past 20 years degraded with time, in a manner that differed between soil types and phylogenetic groups of microbes.


Assuntos
Fungos/genética , Células Procarióticas/metabolismo , Biodiversidade , Ecossistema , Fungos/classificação , Análise de Sequência , Microbiologia do Solo
8.
PLoS One ; 15(8): e0237507, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813726

RESUMO

DNA barcoding can identify biological species and provides an important tool in diverse applications, such as conserving species and identifying pathogens, among many others. If combined with statistical tests, DNA barcoding can focus taxonomic scrutiny onto anomalous species identifications based on morphological features. Accordingly, we put nonparametric tests into a taxonomic context to answer questions about our sequence dataset of the formal fungal barcode, the nuclear ribosomal internal transcribed spacer (ITS). For example, does DNA barcoding concur with annotated species identifications significantly better if expert taxonomists produced the annotations? Does species assignment improve significantly if sequences are restricted to lengths greater than 500 bp? Both questions require a figure of merit to measure of the accuracy of species identification, typically provided by the probability of correct identification (PCI). Many articles on DNA barcoding use variants of PCI to measure the accuracy of species identification, but do not provide the variants with names, and the absence of explicit names hinders the recognition that the different variants are not comparable from study to study. We provide four variant PCIs with a name and show that for fixed data they follow systematic inequalities. Despite custom, therefore, their comparison is at a minimum problematic. Some popular PCI variants are particularly vulnerable to errors in species annotation, insensitive to improvements in a barcoding pipeline, and unable to predict identification accuracy as a database grows, making them unsuitable for many purposes. Generally, the Fractional PCI has the best properties as a figure of merit for species identification. The fungal genus Ramaria provides unusual taxonomic difficulties. As a case study, it shows that a good taxonomic background can be combined with the pertinent summary statistics of molecular results to improve the identification of doubtful samples, linking both disciplines synergistically.


Assuntos
Código de Barras de DNA Taxonômico/métodos , DNA Fúngico/análise , DNA Espaçador Ribossômico/análise , Fungos/classificação , Fungos/genética , Análise de Sequência de DNA/métodos , Teorema de Bayes , Modelos Estatísticos , Filogenia , Especificidade da Espécie
9.
PLoS One ; 15(7): e0235855, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32658904

RESUMO

This paper represents the first article in a series on Yunnanese microfungi. We herein provide insights into Magnolia species associated with microfungi. All presented data are reported from the Kunming Botanical Gardens. Final conclusions were derived from the morphological examination of specimens coupled with phylogenetic sequence data to better integrate taxa into appropriate taxonomic ranks and infer their relationships. Shearia formosa, the type species of Shearia, lacks type material, and its phylogenetic position accordingly remains unresolved. A fresh collection of Shearia formosa, obtained from Magnolia denudata and M. soulangeana in China, therefore, designated a neotype for stabilizing the application of the species and/or genus name. Phylogenetic analyses of a combined DNA data matrix containing SSU, LSU, RPB2 and TEF loci of representative Pleosporales revealed that the genera Crassiperidium, Longiostiolum and Shearia are a well-defined monophylum. It is recognized as the family Longiostiolaceae and strongly supported by Bayesian and Maximum Likelihood methods. Its members are characterized by immersed to semi-immersed, globose to subglobose ascomata with a central, periphysate ostiole, a peridium composed of rectangular to polygonal cells, cylindrical to clavate asci, broadly fusiform, hyaline to pale brown ascospores, a coelomycetous asexual morph with pycnidial conidiomata, enteroblastic, annellidic, ampulliform, doliiform or cylindrical conidiogenous cells and cylindrical to fusiform, transverse and sometimes laterally distoseptate conidia without a sheath or with a basal lateral sheath. Nigrograna magnoliae sp. nov. is introduced from Magnolia denudata with both asexual and sexual morphs. We observed the asexual morph of Brunneofusispora sinensis from the culture and therefore amended the generic and species descriptions of Brunneofusispora.


Assuntos
Fungos/classificação , Magnolia/microbiologia , Filogenia , Código de Barras de DNA Taxonômico , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/citologia , Fungos/genética , Fungos/patogenicidade , Esporos Fúngicos/citologia
10.
Extremophiles ; 24(5): 749-758, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705341

RESUMO

Psychrophilic fungi are a critical biotic component in cold deserts that serves a central role in nutrient recycling and biogeochemical cycles. Despite their ecological significance, culture-independent studies on psychrophilic mycobiome are limited. In the present study, the fungal diversity patterns across the Drass, an Indian cold desert in the Himalaya, were indexed by targeted amplicon pyrosequencing (ITS). In the Drass dataset, Ascomycota was represented by 92 genera, while 22 genera represented Basidiomycota. The most abundant genus was Conocybe (20.46%). Most of the identified genera were reported in the literature to be prolific extracellular hydrolytic enzyme producers. To identify whether the Drass fungal assemblages share similarities to other cold deserts, these were further compared to Antarctic and Arctic cold deserts. Comparative analysis across the three cold deserts indicated the dominance of Dikarya (Ascomycota and Basidiomycota). The observed alpha diversity, Shannon index as well as Pielou's evenness was highest in the Antarctic followed by Drass and Arctic datasets. The genera Malassezia, Preussia, Pseudogymnoascus, Cadophora, Geopora, Monodictys, Tetracladium, Titaea, Mortierella, and Cladosporium were common to all the cold deserts. Furthermore, Conocybe was represented predominantly in Drass. Interestingly, the genus Conocybe has not been previously reported from any other studies on Antarctic or Arctic biomes. To the best of our knowledge, this is the first fungal metagenome study in Drass soil. Our analysis shows that despite the similarities of low temperature among the cold deserts, a significant differential abundance of fungal communities prevails in the global cold deserts.


Assuntos
Fungos , Metagenoma , Micobioma , Regiões Antárticas , Regiões Árticas , Biodiversidade , Fungos/genética
11.
PLoS One ; 15(7): e0231187, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730267

RESUMO

Little is known of how hurricane-induced deposition of canopy material onto tropical forest floors influences the soil microbial communities involved in decomposition of these materials. In this study, to identify how soil bacterial and fungal communities might change after a hurricane, and their possible roles in the C and N cycles, soils were collected from five 2000 m2 permanent plots in Lowland, Upland and Riparian primary forests in Costa Rica 3 months before and 7 months after Hurricane Otto damaged the forests. The soil Water, inorganic N and Biomass C increased and total organic C decreased Post-Hurricane, all of which best predicted the changes in the Post-Hurricane soil microbial communities. Post-Hurricane soils from all forest types showed significant changes in community composition of total bacteria, total fungi, and five functional groups of microbes (i.e., degrading/lignin degrading, NH4+-producing, and ammonium oxidizing bacteria, and the complex C degrading/wood rot/lignin degrading and ectomycorrhizal fungi), along with a decrease in richness in genera of all groups. As well, the mean proportion of DNA sequences (MPS) of all five functional groups increased. There were also significant changes in the MPS values of 7 different fungal and 7 different bacterial genera that were part of these functional groups. This is the first evidence that hurricane-induced deposition of canopy material is stimulating changes in the soil microbial communities after the hurricane, involving changes in specific taxonomic and functional group genera, and reduction in the community richness while selecting for dominant genera possibly better suited to process the canopy material. These changes may represent examples of taxonomic switching of functionally redundant microbial genera in response to dramatic changes in resource input. It is possible that differences in these microbial communities and genera may serve as indicators of disturbed and recovering regional soil ecosystems, and should be evaluated in the future.


Assuntos
Tempestades Ciclônicas , Florestas , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Costa Rica , Fungos/classificação , Fungos/genética
12.
Food Chem ; 332: 127417, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32629332

RESUMO

The use of UHPH sterilization in the absence of SO2 has been used to eliminate wild microorganisms and inactivate oxidative enzymes. A white must of the Muscat of Alexandria grape variety was continuously processed by UHPH at 300 MPa (inlet temperature: 23-25 °C). The initial microbial load of the settled must was 4-log CFU/mL for both yeast and moulds, and slightly lower for bacteria. After UHPH processing, no microorganisms were detected in 1 mL. UHPH musts remain without fermentative activity for more than 60 days. Concentrations of the thermal markers indicated the absence of thermal damage in the UHPH-treated musts, since 5-hydroxymethylfurfural was not detected. In addition, the must treated by UHPH keeps terpene concentrations similar to those of the untreated controls. A strong inactivation of the oxidative enzymes was observed, with no browning at room temperature for more than 3 days. The antioxidant value of the UHPH-treated must was 156% higher than the control.


Assuntos
Bactérias/crescimento & desenvolvimento , Microbiologia de Alimentos/métodos , Fungos/crescimento & desenvolvimento , Esterilização/métodos , Vinho/análise , Bactérias/enzimologia , Bactérias/metabolismo , Fermentação , Manipulação de Alimentos , Fungos/enzimologia , Fungos/genética , Fungos/metabolismo , Humanos , Dióxido de Enxofre/análise , Paladar , Temperatura , Vitis/química
13.
PLoS One ; 15(6): e0233911, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479550

RESUMO

Promoters are very important for transcriptional regulation and gene expression, and have become invaluable tools for genetic engineering. Owing to the characteristics of obligate biotrophs, molecular research into obligate biotrophic fungi is seriously lagging behind, and very few of their endogenous promoters have been developed. In this study, a WY7 fragment was predicted in the genome of Oidium heveae Steinmann using PromoterScan. Its promoter function was verified with transient transformations (Agrobacterium tumefaciens-mediated transformation, ATMT) in Nicotiana tabacum cv. Xanthi nc. The analysis of the transcription range showed that WY7 could regulate GUS expression in both monocots (Zea mays Linn and Oryza sativa L. spp. Japonica cv. Nipponbare) and dicots (N. tabacum and Hylocereus undulates Britt). The results of the quantitative detection showed that the GUS transient expression levels when regulated by WY7 was more than 11.7 times that of the CaMV 35S promoter in dicots (N. tabacum) and 5.13 times that of the ACT1 promoter in monocots (O. sativa). GUS staining was not detected in the T1 generation of the WY7-GUS transgenic N. tabacum. This showed that WY7 is an inducible promoter. The cis elements of WY7 were predicted using PlantCARE, and further experiments indicated that WY7 was a low temperature- and salt-inducible promoter. Soluble proteins produced by WY7-hpa1Xoo transgenic tobacco elicited hypersensitive responses (HR) in N. tabacum leaves. N. tabacum transformed with pBI121-WY7-hpa1Xoo exhibited enhanced resistance to the tobacco mosaic virus (TMV). The WY7 promoter has a lot of potential as a tool for plant genetic engineering. Further in-depth studies will help to better understand the transcriptional regulation mechanisms of O. heveae.


Assuntos
Fungos/genética , Regulação Fúngica da Expressão Gênica , Engenharia Genética/métodos , Doenças das Plantas/prevenção & controle , Regiões Promotoras Genéticas , Fungos/patogenicidade , Genoma Fúngico , Hevea/genética , Hevea/microbiologia , Interações Hospedeiro-Patógeno/genética , Magnoliopsida/genética , Magnoliopsida/microbiologia , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Plantas Geneticamente Modificadas , Tabaco/genética , Tabaco/microbiologia , Transformação Genética , Zea mays/genética , Zea mays/microbiologia
15.
Int J Food Microbiol ; 331: 108712, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32563775

RESUMO

The bread-making quality of wheat depends on the viscoelastic properties of the dough in which gluten proteins play an important role. The quality of gluten proteins is influenced by the genetics of the different wheat varieties and environmental factors. Occasionally, a near complete loss of gluten strength, measured as the maximum resistance towards stretching (Rmax), is observed in grain lots of Norwegian wheat. It is hypothesized that the loss of gluten quality is caused by degradation of gluten proteins by fungal proteases. To identify fungi associated with loss of gluten strength, samples from a selection of wheat grain lots with weak gluten (n = 10, Rmax < 0.3 N) and strong gluten (n = 10, Rmax ≥ 0.6 N) was analyzed for the abundance of fungal operational taxonomic units (OTUs) using DNA metabarcoding of the nuclear ribosomal Internal Transcribed Spacer (ITS) region ITS1. The DNA quantities for a selection of fungal pathogens of wheat, and the total amount of fungal DNA, were analyzed by quantitative PCR (qPCR). The mean level of total fungal DNA was higher in grain samples with weak gluten compared to grain samples with strong gluten. Heightened quantities of DNA from fungi within the Fusarium Head Blight (FHB) complex, i.e. Fusarium avenaceum, Fusarium graminearum, Microdochium majus, and Microdochium nivale, were observed in grain samples with weak gluten compared to those with strong gluten. Microdochium majus was the dominant fungus in the samples with weak gluten. Stepwise regression modeling based on different wheat quality parameters, qPCR data, and the 35 most common OTUs revealed a significant negative association between gluten strength and three OTUs, of which the OTU identified as M. majus was the most abundant. The same analysis also revealed a significant negative relationship between gluten strength and F. avenaceum detected by qPCR, although the DNA levels of this fungus were low compared to those of M. majus. In vitro growth rate studies of a selection of FHB species showed that all the tested isolates were able to grow with gluten as a sole nitrogen source. In addition, proteins secreted by these fungi in liquid cultures were able to hydrolyze gluten substrate proteins in zymograms, confirming their capacity to secrete gluten-degrading proteases. The identification of fungi with potential to influence gluten quality can enable the development of strategies to minimize future problems with gluten strength in food-grade wheat.


Assuntos
Microbiologia de Alimentos , Fungos/classificação , Glutens/química , Triticum/química , Triticum/microbiologia , DNA Fúngico/genética , Grão Comestível/microbiologia , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Glutens/metabolismo , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Triticum/metabolismo
16.
Arch Microbiol ; 202(9): 2391-2400, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32588084

RESUMO

An amplicon metagenomic approach based on the ITS1 region of fungal rDNA was employed to identify the composition of fungal communities associated with diseases of pear fruits during postharvest storage. The sampled fruits were harvested at an orchard using routine management practices involving treatments with various chemical fungicides and were transferred to a storage packinghouse. Effective tags of reading sequences clustered into 53 OTUs whereas Ascomycota was the dominant phylum (83.4%) followed by Basidiomycota (15.8%). Our results revealed that four genera, Penicillium, Rhodotorula, Alternaria and Cladosporium were the most abundant representing 59-95% of the relative abundance per sample. The interruption of chemical treatments during the last month before harvest altered the structure of the fungal community of fruits among untreated and treated samples, mainly in cases of relative abundance of Penicillium and Rhodotorula genera. We hypothesize that various antagonistic interactions might occur on fruit surfaces among the detected fungal genera whose relative abundances were affected by fungicide treatments. Interestingly, some common pre- and postharvest pear fungal pathogens were either less present (such as Moniliana), or undetected (such as Aspergillus, Venturia and Septoria) in untreated and treated samples.


Assuntos
Microbiologia de Alimentos , Frutas/microbiologia , Fungos , Metagenômica , Micobioma , Pyrus/microbiologia , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , Fungicidas Industriais/farmacologia , Micobioma/efeitos dos fármacos , Micobioma/genética
17.
Curr Opin Plant Biol ; 56: 74-80, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32492572

RESUMO

Plant fungal pathogens can be classified according to their lifestyles. Biotrophs feed on living tissue and constitute an economically significant group of pathogens historically. Necrotrophs, which feed on dead tissue, have become economically significant over recent decades, especially those of the Dothideomycetes, which produce necrotrophic effectors (NEs) to modulate the host response. Some of these pathogens interact with their hosts in an inverse gene-for-gene manner, where NEs are recognized by specific dominant genes in the host leading to host-mediated programmed cell death allowing the pathogen to cause disease. Whereas the NE genes tend to be unique, several of the plant 'susceptibility' genes belong to the nucleotide-binding leucine-rich repeat class of disease 'resistance' genes, and one is a wall-associated kinase. These susceptible interactions exhibit hallmarks of defense responses to biotrophic pathogens. Therefore, there is now accumulating evidence that many necrotrophic specialists hijack the resistance mechanisms that are effective against biotrophic pathogens.


Assuntos
Genes de Plantas , Doenças das Plantas , Resistência à Doença/genética , Fungos/genética , Humanos , Doenças das Plantas/genética , Plantas/genética
18.
Arch Microbiol ; 202(8): 2033-2058, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32506150

RESUMO

Polyaromatic hydrocarbons (PAHs) are considered as hazardous organic priority pollutants. PAHs have immense public concern and critical environmental challenge around the globe due to their toxic, carcinogenic, and mutagenic properties, and their ubiquitous distribution, recalcitrance as well as persistence in environment. The knowledge about harmful effects of PAHs on ecosystem along with human health has resulted in an interest of researchers on degradation of these compounds. Whereas physico-chemical treatment of PAHs is cost and energy prohibitive, bioremediation i.e. degradation of PAHs using microbes is becoming an efficient and sustainable approach. Broad range of microbes including bacteria, fungi, and algae have been found to have capability to use PAHs as carbon and energy source under both aerobic and anaerobic conditions resulting in their transformation/degradation. Microbial genetic makeup containing genes encoding catabolic enzymes is responsible for PAH-degradation mechanism. The degradation capacity of microbes may be induced by exposing them to higher PAH-concentration, resulting in genetic adaptation or changes responsible for high efficiency towards removal/degradation. In last few decades, mechanism of PAH-biodegradation, catabolic gene system encoding catabolic enzymes, and genetic adaptation and regulation have been investigated in detail. This review is an attempt to overview current knowledge of microbial degradation mechanism of PAHs, its genetic regulation with application of genetic engineering to construct genetically engineered microorganisms, specific catabolic enzyme activity, and application of bioremediation for reclamation of PAH-contaminated sites. In addition, advanced molecular techniques i.e. genomic, proteomic, and metabolomic techniques are also discussed as powerful tools for elucidation of PAH-biodegradation/biotransformation mechanism in an environmental matrix.


Assuntos
Bactérias , Biodegradação Ambiental , Microbiologia Ambiental , Poluentes Ambientais/metabolismo , Fungos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Biotransformação , Fungos/genética , Fungos/metabolismo , Engenharia Genética , Genoma Bacteriano/genética , Genoma Fúngico/genética
19.
Arch Microbiol ; 202(7): 1861-1872, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32448959

RESUMO

In addition to a wide variety of anaerobic and facultative anaerobic bacteria, camel rumen also harbors a diverse of eukaryotic organisms. In the present study, the eukaryotic communities of camel rumen were characterized using 18S rRNA amplicon sequencing. Metagenomic DNA was isolated from rumen samples of fourteen adult Bikaneri and Kachchhi breeds of camel fed different diets containing Jowar, Bajra, Maize, and Guar. Illumina sequencing generated 27,161,904 number of reads corresponding to 1543 total operational taxonomic units (OTUs). Taxonomic classification of community metagenome sequences from all the samples revealed the presence of 92 genera belonging to 16 different divisions, out of which Ciliophora (73%), Fungi (13%) and Streptophyta (9%) were found to be the most dominant. Notably, the abundance of Ciliophora was significantly higher in the case of Guar feed, while Fungi was significantly higher in the case of Maize feed, indicating the influence of cellulose and hemicellulose content of feedstuff on the composition of eukaryotes. The results suggest that the camel rumen eukaryotes are highly dynamic and depend on the type of diet given to the animal. Pearson's correlation analysis suggested the ciliate protozoa and fungi were negatively correlated with each other. To the best of our knowledge, this is first systematic study to characterize camel rumen eukaryotes, which has provided newer information regarding eukaryotic diversity patterns amongst camel fed on different diets.


Assuntos
Camelus/microbiologia , Camelus/parasitologia , Cilióforos , Dieta , Fungos , Rúmen/microbiologia , Rúmen/parasitologia , Animais , Cilióforos/classificação , Cilióforos/genética , Fungos/classificação , Fungos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Metagenoma , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
20.
PLoS One ; 15(5): e0232029, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374732

RESUMO

BACKGROUND: Translationally controlled tumor protein (TCTP) is a conserved, multifunctional protein involved in numerous cellular processes in eukaryotes. Although the functions of TCTP have been investigated sporadically in animals, invertebrates, and plants, few lineage-specific activities of this molecule, have been reported. An exception is in Arabidopsis thaliana, in which TCTP (AtTCTP1) functions in stomatal closuer by regulating microtubule stability. Further, although the development of next-generation sequencing technologies has facilitated the analysis of many eukaryotic genomes in public databases, inter-kingdom comparative analyses using available genome information are comparatively scarce. METHODOLOGY: To carry out inter-kingdom comparative analysis of TCTP, TCTP genes were identified from 377 species. Then phylogenetic analysis, prediction of protein structure, molecular docking simulation and molecular dynamics analysis were performed to investigate the evolution of TCTP genes and their binding proteins. RESULTS: A total of 533 TCTP genes were identified from 377 eukaryotic species, including protozoa, fungi, invertebrates, vertebrates, and plants. Phylogenetic and secondary structure analyses reveal lineage-specific evolution of TCTP, and inter-kingdom comparisons highlight the lineage-specific emergence of, or changes in, secondary structure elements in TCTP proteins from different kingdoms. Furthermore, secondary structure comparisons between TCTP proteins within each kingdom, combined with measurements of the degree of sequence conservation, suggest that TCTP genes have evolved to conserve protein secondary structures in a lineage-specific manner. Additional tertiary structure analysis of TCTP-binding proteins and their interacting partners and docking simulations between these proteins further imply that TCTP gene variation may influence the tertiary structures of TCTP-binding proteins in a lineage-specific manner. CONCLUSIONS: Our analysis suggests that TCTP has undergone lineage-specific evolution and that structural changes in TCTP proteins may correlate with the tertiary structure of TCTP-binding proteins and their binding partners in a lineage-specific manner.


Assuntos
Biomarcadores Tumorais/genética , Biomarcadores Tumorais/fisiologia , Evolução Molecular , Especiação Genética , Sequência de Aminoácidos , Animais , Biomarcadores Tumorais/química , Sequência Conservada , Células Eucarióticas/classificação , Células Eucarióticas/metabolismo , Fungos/classificação , Fungos/genética , Humanos , Invertebrados/classificação , Invertebrados/genética , Mamíferos/classificação , Mamíferos/genética , Simulação de Acoplamento Molecular , Filogenia , Células Vegetais/classificação , Células Vegetais/metabolismo , Células Procarióticas/classificação , Células Procarióticas/metabolismo , Ligação Proteica , Estrutura Secundária de Proteína , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA