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1.
Nat Genet ; 52(10): 1111-1121, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32989321

RESUMO

Wild tomato species represent a rich gene pool for numerous desirable traits lost during domestication. Here, we exploited an introgression population representing wild desert-adapted species and a domesticated cultivar to establish the genetic basis of gene expression and chemical variation accompanying the transfer of wild-species-associated fruit traits. Transcriptome and metabolome analysis of 580 lines coupled to pathogen sensitivity assays resulted in the identification of genomic loci associated with levels of hundreds of transcripts and metabolites. These associations occurred in hotspots representing coordinated perturbation of metabolic pathways and ripening-related processes. Here, we identify components of the Solanum alkaloid pathway, as well as genes and metabolites involved in pathogen defense and linking fungal resistance with changes in the fruit ripening regulatory network. Our results outline a framework for understanding metabolism and pathogen resistance during tomato fruit ripening and provide insights into key fruit quality traits.


Assuntos
Resistência à Doença/genética , Lycopersicon esculentum/genética , Metaboloma/genética , Transcriptoma/genética , Alcaloides/genética , Domesticação , Frutas/genética , Frutas/crescimento & desenvolvimento , Frutas/parasitologia , Fungos/genética , Fungos/patogenicidade , Regulação da Expressão Gênica de Plantas/genética , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/microbiologia , Redes e Vias Metabólicas/genética , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Solanum/genética , Solanum/microbiologia
2.
Emerg Microbes Infect ; 9(1): 1958-1964, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32815458

RESUMO

Objectives Severe or critical COVID-19 is associated with intensive care unit admission, increased secondary infection rate, and would lead to significant worsened prognosis. Risks and characteristics relating to secondary infections in severe COVID-19 have not been described. Methods Severe and critical COVID-19 patients from Shanghai were included. We collected lower respiratory, urine, catheters, and blood samples according to clinical necessity and culture and mNGS were performed. Clinical and laboratory data were archived. Results We found 57.89% (22/38) patients developed secondary infections. The patient receiving invasive mechanical ventilation or in critical state has a higher chance of secondary infections (P<0.0001). The most common infections were respiratory, blood-stream and urinary infections, and in respiratory infections, the most detected pathogens were gram-negative bacteria (26, 50.00%), following by gram-positive bacteria (14, 26.92%), virus (6, 11.54%), fungi (4, 7.69%), and others (2, 3.85%). Respiratory Infection rate post high flow, tracheal intubation, and tracheotomy were 12.90% (4/31), 30.43% (7/23), and 92.31% (12/13) respectively. Secondary infections would lead to lower discharge rate and higher mortality rate. Conclusion Our study originally illustrated secondary infection proportion in severe and critical COVID-19 patients. Culture accompanied with metagenomics sequencing increased pathogen diagnostic rate. Secondary infections risks increased after receiving invasive respiratory ventilations and intravascular devices, and would lead to a lower discharge rate and a higher mortality rate.


Assuntos
Bacteriemia/patologia , Infecções Bacterianas/patologia , Infecções por Coronavirus/patologia , Fungemia/patologia , Micoses/patologia , Infecções Oportunistas/patologia , Pneumonia Viral/patologia , Infecções Respiratórias/patologia , Infecções Urinárias/patologia , Idoso , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Bacteriemia/virologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Infecções Bacterianas/virologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Estado Terminal , Feminino , Fungemia/microbiologia , Fungemia/mortalidade , Fungemia/virologia , Fungos/patogenicidade , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/patogenicidade , Humanos , Unidades de Terapia Intensiva , Pulmão/microbiologia , Pulmão/patologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Micoses/microbiologia , Micoses/mortalidade , Micoses/virologia , Infecções Oportunistas/microbiologia , Infecções Oportunistas/mortalidade , Infecções Oportunistas/virologia , Pandemias , Pneumonia Viral/microbiologia , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Respiração Artificial/efeitos adversos , Infecções Respiratórias/microbiologia , Infecções Respiratórias/mortalidade , Infecções Respiratórias/virologia , Estudos Retrospectivos , Risco , Índice de Gravidade de Doença , Análise de Sobrevida , Infecções Urinárias/microbiologia , Infecções Urinárias/mortalidade , Infecções Urinárias/virologia
4.
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
6.
PLoS One ; 15(6): e0234390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525917

RESUMO

Fungicide use in the United States to manage soybean diseases has increased in recent years. The ability of fungicides to reduce disease-associated yield losses varies greatly depending on multiple factors. Nonetheless, historical data are useful to understand the broad sense and long-term trends related to fungicide use practices. In the current study, the relationship between estimated soybean yield losses due to selected foliar diseases and foliar fungicide use was investigated using annual data from 28 soybean growing states over the period of 2005 to 2015. For national and regional (southern and northern United States) scale data, mixed effects modeling was performed considering fungicide use as a fixed and state and year as random factors to generate generalized R2 values for marginal (R2GLMM(m); contains only fixed effects) and conditional (R2GLMM(c); contains fixed and random effects) models. Similar analyses were performed considering soybean production data to see how fungicide use affected production. Analyses at both national and regional scales showed that R2GLMM(m) values were significantly smaller compared to R2GLMM(c) values. The large difference between R2 values for conditional and marginal models indicated that the variation of yield loss as well as production were predominantly explained by the state and year rather than the fungicide use, revealing the general lack of fit between fungicide use and yield loss/production at national and regional scales. Therefore, regression models were fitted across states and years to examine their importance in combination with fungicide use on yield loss or yield. In the majority of cases, the relationship was nonsignificant. However, the relationship between soybean yield and fungicide use was significant and positive for majority of the years in the study. Results suggest that foliar fungicides conferred yield benefits in most of the years in the study. Furthermore, the year-dependent usefulness of foliar fungicides in mitigating soybean yield losses suggested the possible influence of temporally fluctuating abiotic factors on the effectiveness of foliar fungicides and/or target disease occurrence and associated loss magnitudes.


Assuntos
Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Soja/crescimento & desenvolvimento , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Fungos/efeitos dos fármacos , Fungos/patogenicidade , Fungicidas Industriais/administração & dosagem , Fungicidas Industriais/provisão & distribução , Modelos Biológicos , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Soja/efeitos dos fármacos , Soja/microbiologia , Análise Espaço-Temporal , Estados Unidos
7.
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
8.
Arch Microbiol ; 202(9): 2379-2390, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32588083

RESUMO

In the aquaculture industry, the selection and quality of feed are highly relevant because their integrity and management have an impact on the health and development of organisms. In general, feeds contamination depends on storage conditions and formulation. Furthermore, it has been recognized that filamentous fungi are among the most important contaminating agent in formulated feeds. Therefore, the purpose of this research was to identify saprophytic fungi capable of proliferating in commercial feeds, as well as determining their prevalence, extracellular enzymes profile, ability to assimilate carbon sources, and finally their ability to produce aflatoxins. In order to do that, twenty-two fungi were isolated from commercial fish feeds. After, the species Aspergillus chevalieri, A. cristatus, A. sydowii, A. versicolor, A. flavus, A. creber, and Lichtheimia ramosa were identified. These fungi were able to produce extracellular enzymes, such as phosphatases, esterases, proteases, ß-glucosidase, and N-acetyl-ß-glucosaminidase. The isolated fungi showed no selective behavior in the assimilation of the different carbon sources, showing a strong metabolic diversity. Prevalence percentages above 85% were recorded. Among all fungi studied, A. flavus M3-C1 had the highest production of aflatoxins when this strain was inoculated directly in the feeds (295 ppb). The aflatoxin production by this strain under the experimental setting is above the permitted levels, and it has been established that high levels of aflatoxins in feeds can cause alterations in fish growth as well as the development of cancerous tumors in the liver, in addition to enhancing mortality.


Assuntos
Aflatoxinas/análise , Ração Animal/microbiologia , Fungos/classificação , Fungos/crescimento & desenvolvimento , Animais , Organismos Aquáticos , Proliferação de Células , Peixes , Fungos/isolamento & purificação , Fungos/patogenicidade
9.
Nat Commun ; 11(1): 2955, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32528123

RESUMO

The ecological niche can be thought of as a volume in multidimensional space, where each dimension describes an abiotic condition or biotic resource required by a species. The shape, size, and evolution of this volume strongly determine interactions among species and influence their current and potential geographical distributions, but the geometry of niches is poorly understood. Here, we analyse temperature response functions and host plant ranges for hundreds of potentially destructive plant-associated fungi and oomycetes. We demonstrate that niche specialization is uncorrelated on abiotic (i.e. temperature response) and biotic (i.e. host range) axes, that host interactions restrict fundamental niche breadth to form the realized niche, and that both abiotic and biotic niches show limited phylogenetic constraint. The ecological terms 'generalist' and 'specialist' therefore do not apply to these microbes, as specialization evolves independently on different niche axes. This adaptability makes plant pathogens a formidable threat to agriculture and forestry.


Assuntos
Plantas/microbiologia , Ecossistema , Fungos/patogenicidade , Filogenia
11.
PLoS One ; 15(5): e0229630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401759

RESUMO

Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by traumatic implantation of many species of black fungi. Due to the refractoriness of some cases and common recurrence of CBM, a more effective and less time-consuming treatment is mandatory. The aim of this study was to identify compounds with in vitro antifungal activity in the Pathogen Box® compound collection against different CBM agents. Synergism of these compounds with drugs currently used to treat CBM was also assessed. An initial screening of the drugs present in this collection at 1 µM was performed with a Fonsecaea pedrosoi clinical strain according to the EUCAST protocol. The compounds with activity against this fungus were also tested against other seven etiologic agents of CBM (Cladophialophora carrionii, Phialophora verrucosa, Exophiala jeanselmei, Exophiala dermatitidis, Fonsecaea monophora, Fonsecaea nubica, and Rhinocladiella similis) at concentrations ranging from 0.039 to 10 µM. The analysis of potential synergism of these compounds with itraconazole and terbinafine was performed by the checkerboard method. Eight compounds inhibited more than 60% of the F. pedrosoi growth: difenoconazole, bitertanol, iodoquinol, azoxystrobin, MMV688179, MMV021013, trifloxystrobin, and auranofin. Iodoquinol produced the lowest MIC values (1.25-2.5 µM) and MMV688179 showed MICs that were higher than all compounds tested (5 - >10 µM). When auranofin and itraconazole were tested in combination, a synergistic interaction (FICI = 0.37) was observed against the C. carrionii isolate. Toxicity analysis revealed that MMV021013 showed high selectivity indices (SI ≥ 10) against the fungi tested. In summary, auranofin, iodoquinol, and MMV021013 were identified as promising compounds to be tested in CBM models of infection.


Assuntos
Antifúngicos/farmacologia , Cromoblastomicose/tratamento farmacológico , Sinergismo Farmacológico , Fungos/patogenicidade , Acetatos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Auranofina/farmacologia , Compostos de Bifenilo/farmacologia , Cromoblastomicose/microbiologia , Cromoblastomicose/patologia , Dioxolanos/farmacologia , Exophiala/efeitos dos fármacos , Exophiala/patogenicidade , Fungos/efeitos dos fármacos , Humanos , Iminas/farmacologia , Iodoquinol/farmacologia , Pirimidinas/farmacologia , Estrobilurinas/farmacologia , Triazóis/farmacologia
12.
Nat Commun ; 11(1): 2636, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457288

RESUMO

The mechanisms regulating community composition and local dominance of trees in species-rich forests are poorly resolved, but the importance of interactions with soil microbes is increasingly acknowledged. Here, we show that tree seedlings that interact via root-associated fungal hyphae with soils beneath neighbouring adult trees grow faster and have greater survival than seedlings that are isolated from external fungal mycelia, but these effects are observed for species possessing ectomycorrhizas (ECM) and not arbuscular mycorrhizal (AM) fungi. Moreover, survival of naturally-regenerating AM seedlings over ten years is negatively related to the density of surrounding conspecific plants, while survival of ECM tree seedlings displays positive density dependence over this interval, and AM seedling roots contain greater abundance of pathogenic fungi than roots of ECM seedlings. Our findings show that neighbourhood interactions mediated by beneficial and pathogenic soil fungi regulate plant demography and community structure in hyperdiverse forests.


Assuntos
Micorrizas/fisiologia , Microbiologia do Solo , Árvores/microbiologia , China , Florestas , Fungos/genética , Fungos/patogenicidade , Fungos/fisiologia , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Modelos Biológicos , Biologia Molecular , Micorrizas/genética , Micorrizas/patogenicidade , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Simbiose , Árvores/crescimento & desenvolvimento
14.
Zhongguo Zhong Yao Za Zhi ; 45(5): 1047-1052, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32237444

RESUMO

Leaf blight is the main disease of Asarum. At present, chemical treatment is main measure for disease control, and there is no report on biological control. In order to achieve the biological control of Asarum leaf blight, the biocontrol strains with antagonistic effect on Asarum leaf blight were screened. The rhizosphere bacteria of healthy Asarum plants were isolated by soil dilution method, and the isolated strains were screened by the methods of antagonistic antifungal and fermentation liquid antifungal, then the strains were identified and the control effect in vivo was determined. Abiocontrol bacterial strains S2-31 which with high antagonism to leaf blight was obtained from more than 100 isolated strains. The inhibitory rates of antagonistic antifungal and fermentation liquid antifungal reached 92.47% and 60.56%, respectively. It was identified by morphology and 16 S rDNA sequence analysis, and the strain was identified as Brevibacillus laterosporus. The results of indoor potted experiment showed that the control effect was 79.87%, 71.44% and 66.82% on the 3 rd, 5 th and 7 th day after inoculation, respectively, which indicated that S2-31 could reduce the disease index and control the development of Asarum leaf blight.


Assuntos
Asarum/microbiologia , Agentes de Controle Biológico , Firmicutes , Doenças das Plantas/prevenção & controle , Microbiologia do Solo , Antibiose , DNA Ribossômico , Fungos/patogenicidade , Doenças das Plantas/microbiologia , Rizosfera
15.
Zhongguo Zhong Yao Za Zhi ; 45(3): 478-484, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237503

RESUMO

Fungal disease is an important factor restricting the healthy development of Gastrodia elata industry. The control of fungal disease in G. elata is an important issue in production. This paper makes a detailed investigation on the current situation of G. elata disease in China through statistics on the failure rate, rotten pit rate and occurrence rate of G. elata disease in the main producing areas of China. It was found that G. elata disease was mainly infected from the top bud and junction, causing the occurrence rate of disease was 6%-17%, and the yield decreased by 10%-30%. The 23 dominant fungi were isolated from 18 typical G. elata disease samples. Through identification of colony morphology, mycelium morphology, spore morphology and genetic characteristics, they were finally identified as 13 species, belonging to 7 families and 7 genera. Trichoderma harzianum, Ilyonectria sp. and Ilyonectria destructans are the most frequently separated. Their isolation frequency were 22.22%,16.67%,16.67% respectively. Ilyonectria sp. and I. destructans were the first time isolated from G. elata disease samples. They may be the main pathogens causing soil-borne diseases of G. elata. T. harzianum has certain potential as Gastrodia biocontrol bacteria. This study can provide a theoretical basis for the research and development of control technology of Gastrodia fungi disease.


Assuntos
Fungos/patogenicidade , Gastrodia/microbiologia , Doenças das Plantas/microbiologia , China , Fungos/classificação
16.
PLoS One ; 15(4): e0226863, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240194

RESUMO

Global trade and climate change are responsible for a surge in foreign invasive species and emerging pests and pathogens across the world. Early detection and surveillance activities are essential to monitor the environment and prevent or mitigate future ecosystem impacts. Molecular diagnostics by DNA testing has become an integral part of this process. However, for environmental applications, there is a need for cost-effective and efficient point-of-use DNA testing to obtain accurate results from remote sites in real-time. This requires the development of simple and fast sample processing and DNA extraction, room-temperature stable reagents and a portable instrument. We developed a point-of-use real-time Polymerase Chain Reaction system using a crude buffer-based DNA extraction protocol and lyophilized, pre-made, reactions for on-site applications. We demonstrate the use of this approach with pathogens and pests covering a broad spectrum of known undesirable forest enemies: the fungi Sphaerulina musiva, Cronartium ribicola and Cronartium comandrae, the oomycete Phytophthora ramorum and the insect Lymantria dispar. We obtained positive DNA identification from a variety of different tissues, including infected leaves, pathogen spores, or insect legs and antenna. The assays were accurate and yielded no false positive nor negative. The shelf-life of the lyophilized reactions was confirmed after one year at room temperature. Finally, successful tests conducted with portable thermocyclers and disposable instruments demonstrate the suitability of the method, named in Situ Processing and Efficient Environmental Detection (iSPEED), for field testing. This kit fits in a backpack and can be carried to remote locations for accurate and rapid detection of pests and pathogens.


Assuntos
Monitoramento Ambiental , Fungos/isolamento & purificação , Espécies Introduzidas , Árvores/microbiologia , Mudança Climática , Ecossistema , Florestas , Fungos/genética , Fungos/patogenicidade , Humanos , Controle de Pragas/métodos , Reação em Cadeia da Polimerase , Árvores/genética , Árvores/crescimento & desenvolvimento
17.
J Appl Microbiol ; 129(3): 712-727, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32249987

RESUMO

AIMS: Penicillium digitatum, Alternaria alternata and Colletotrichum gloeosporioides are pathogens responsible for large decays and production losses of citrus. They are commonly controlled by fungicides, whose excessive applications have led to the emergence of resistant P. digitatum strains. Alternative approaches are imperative for sustainable and environmental harmless citrus production, being biological control a promising strategy. The objective was to evaluate the potential of Trichoderma strains native from the rhizosphere of citrus trees to control these pathogens. METHODS AND RESULTS: Seven strains were isolated and identified as Trichoderma harzianum, T. guizhouense, T. atroviride and T. koningiopsis through morphological and molecular analyses. Five of them showed effective antagonist performance in vitro against the pathogens. The strain T. harzianum IC-30 was the best biological control agent in vivo, obtaining a reduction of rot percentage around 80% after 3 weeks of infection of oranges with P. digitatum A21 (resistant to pyrimethanil). This strain also showed the highest chitinase and glucanase activities. CONCLUSIONS: Trichoderma harzianum IC-30 is an optimal antagonist for the control of green mould spreading and other pathogens in post-harvest citrus fruits. SIGNIFICANCE AND IMPACT OF THE STUDY: The strain combined with supplementary practices could lead to sustainable management of citrus fungal diseases, dispensing with synthetic fungicides.


Assuntos
Citrus sinensis/microbiologia , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Doenças das Plantas/prevenção & controle , Trichoderma/fisiologia , Antibiose , Fungos/efeitos dos fármacos , Fungos/patogenicidade , Controle Biológico de Vetores , Doenças das Plantas/microbiologia , Pirimidinas/farmacologia , Rizosfera
18.
Diagn Microbiol Infect Dis ; 97(2): 115016, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32111415

RESUMO

The SENTRY Antimicrobial Surveillance Program has monitored bloodstream infections (BSIs) from patients in medical centers worldwide since 1997. In this report, we examine the frequency of occurrence and antimicrobial susceptibility profiles of 6741 bacterial and 222 fungal pathogens causing BSI in 16 medical centers from 2012 to 2017. These results were stratified according to patient age, intensive care unit (ICU) location, and hospital onset (HO) versus community onset (CO) of infection. The leading pathogen isolated from patients in all age groups (range, 20.3-32.5%), except for those >64 years old (19.9%), was Staphylococcus aureus. Escherichia coli was the most common agent in patients over 64 years of age (26.7%). S. aureus was frequently recovered from patients with HO or CO BSI (20.9-24.1%). However, E. coli was the most commonly isolated species (24.5%) from CO infections. BSIs caused by vancomycin-resistant enterococci, penicillin-nonsusceptible S. pneumoniae, extended-spectrum ß-lactamase-producing Klebsiella spp., carbapenem-resistant Enterobacteriaceae, and multidrug-resistant Pseudomonas aeruginosa were more common among patients in ICUs compared to patients hospitalized in a non-ICU setting. The frequency of methicillin-resistant S. aureus (MRSA) was slightly higher in the non-ICU population (37.5%) compared with the ICU group (34.1%). A trend toward a decrease in BSIs due to Gram-positive cocci and an increase in infections with Gram-negative bacilli were observed. Overall, the frequency of resistant phenotypes was high for S. aureus (MRSA; 37.0%), enterococci (vancomycin-resistant enterococci; 24.6%), Klebsiella spp. (extended-spectrum ß-lactamase phenotype; 21.5%), and P. aeruginosa (multidrug-resistant; 15.4%) and generally declined from 2012 to 2017, whereas the frequency of penicillin-nonsusceptible Streptococcus pneumoniae (3.4%) and carbapenem-resistant Enterobacteriaceae (1.5%) was low overall and both resistant phenotypes declined over time. Fluconazole-resistant Candida spp. isolates were only detected in years 2013-2015.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bacteriemia/microbiologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Farmacorresistência Fúngica Múltipla , Fungemia/microbiologia , Fungos/efeitos dos fármacos , Adolescente , Adulto , Idoso , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Criança , Pré-Escolar , Infecção Hospitalar/microbiologia , Monitoramento Epidemiológico , Fungos/isolamento & purificação , Fungos/patogenicidade , Saúde Global , Humanos , Lactente , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Adulto Jovem
19.
Int J Mol Sci ; 21(5)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150834

RESUMO

Arabidopsis contains 34 genes for glycosylphosphatidylinositol (GPI)-anchored LTPg proteins. A motif analysis has placed these into four groups. With one exception, all are produced with a signal peptide and are most likely attached to the cell membrane via the GPI anchor. Several of the LTPg genes across the four groups are downregulated in syncytia induced by the beet cyst nematode Heterodera schachtii. We have here studied At3g22600 encoding LTPg5, which is the most strongly downregulated LTPg gene. It is mainly expressed in roots, and a promoter::GUS line was used to confirm the downregulation in syncytia and also showed downregulation in galls of the root knot nematode Meloidogyne incognita. In contrast, infection with bacteria (Pseudomonas syringae) and fungi (Botrytis cinerea) led to the induction of the gene in leaves. This diverse regulation of LTPg5 indicated a role in resistance, which we confirmed with overexpression lines and a T-DNA mutant. The overexpression lines were more resistant to both nematode species and to P. syringae and B. cinerea, while a knock-out mutant was more susceptible to H. schachtii and P. syringae. Thus, LTPg5 encoded by At3g22600 is part of the Arabidopsis resistance mechanism against pathogens. LTPg5 has probably no direct antimicrobial activity but could perhaps act by associating with a receptor-like kinase, leading to the induction of defense genes such as PR1.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Bactérias/patogenicidade , Fungos/patogenicidade , Doenças das Plantas/imunologia , Folhas de Planta/imunologia , Tylenchoidea/patogenicidade , Animais , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Arabidopsis/parasitologia , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Glicosilfosfatidilinositóis/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Folhas de Planta/parasitologia
20.
Sci Rep ; 10(1): 4212, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144325

RESUMO

In some species of social insects the increased genetic diversity from having multiple breeders in a colony has been shown to improve pathogen resistance. Termite species typically found colonies from single mated pairs and therefore may lack the flexibility to buffer pathogen pressure with increased genetic diversity by varying the initial number of reproductives. However, they can later increase group diversity through colony merging, resulting in a genetically diverse, yet cohesive, workforce. In this study, we investigate whether the increased group diversity from colony fusion benefits social immunity in the subterranean termite Reticulitermes flavipes. We confirm previous findings that colonies of R. flavipes will readily merge and we show that workers will equally groom nestmates and non-nestmates after merging. Despite this, the survival of these merged colonies was not improved after exposure to a fungal pathogen, but instead leveled to that of the more susceptible or the more resistant colony. Our study brings little support to the hypothesis that colony fusion may improve immunity through an increase of genetic diversity in R. flavipes. Instead, we find that following exposure to a lethal pathogen, one colony is heavily influential to the entire group's survival after merging.


Assuntos
Resistência à Doença/imunologia , Fungos/patogenicidade , Variação Genética , Genética Populacional , Isópteros/crescimento & desenvolvimento , Isópteros/genética , Repetições de Microssatélites , Animais , Isópteros/imunologia , Reprodução
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