Seiridium (Sporocadaceae): an important genus of plant pathogenic fungi

NARCIS (Netherlands)

Bonthond, G.; Sandoval-Denis, M.; Groenewald, J.Z.; Crous, P.W.

2018-01-01

The genus Seiridium includes multiple plant pathogenic fungi well-known as causal organisms of cankers on Cupressaceae. Taxonomically, the status of several species has been a topic of debate, as the phylogeny of the genus remains unresolved and authentic ex-type cultures are mostly absent. In the

Synthesis and in vitro antifungal efficacy of oleoyl-chitosan nanoparticles against plant pathogenic fungi.

Science.gov (United States)

Xing, Ke; Shen, Xiaoqiang; Zhu, Xiao; Ju, Xiuyun; Miao, Xiangmin; Tian, Jun; Feng, Zhaozhong; Peng, Xue; Jiang, Jihong; Qin, Sheng

2016-01-01

An antifungal dispersion system was prepared by oleoyl-chitosan (O-chitosan) nanoparticles, and the antifungal activity against several plant pathogenic fungi was investigated. Under scanning electron microscopy, the nanoparticles formulation appeared to be uniform with almost spherical shape. The particle size of nanoparticles was around 296.962 nm. Transmission electron microscopy observation showed that nanoparticles could be well distributed in potato dextrose agar medium. Mycelium growth experiment demonstrated that Nigrospora sphaerica, Botryosphaeria dothidea, Nigrospora oryzae and Alternaria tenuissima were chitosan-sensitive, while Gibberella zeae and Fusarium culmorum were chitosan-resistant. The antifungal index was increased as the concentration of nanoparticles increased for chitosan-sensitive fungi. Fatty acid analyses revealed that plasma membranes of chitosan-sensitive fungi were shown to have lower levels of unsaturated fatty acid than chitosan-resistant fungi. Phylogenetic analysis based on ITS gene sequences indicated that two chitosan-resistant fungi had a near phylogenetic relationship. Results showed that O-chitosan nanoparticles could be a useful alternative for controlling pathogenic fungi in agriculture. Copyright © 2015 Elsevier B.V. All rights reserved.

Sandpits as a reservoir of potentially pathogenic fungi for children

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Anna Wójcik

2016-09-01

Potentially pathogenic fungi are present in the sand taken from sandpits in Łódź. This fact poses a significant threat to child health and therefore proper maintenance and periodic checking of sandpits are of great importance.

The isolation and identification of pathogenic fungi from Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae).

Science.gov (United States)

Meng, Xiang; Hu, Junjie; Ouyang, Gecheng

2017-01-01

Litchi stink-bug, Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae), is one of the most widespread and destructive pest species on Litchi chinensis Sonn and Dimocarpus longan Lour in Southern China. Inappropriate use of chemical pesticides has resulted in serious environmental problems and food pollution. Generating an improved Integrated Pest Management (IPM) strategy for litchi stink-bug in orchard farming requires development of an effective biological control agent. Entomopathogenic fungi are regarded as a vital ecological factor in the suppression of pest populations under field conditions. With few effective fungi and pathogenic strains available to control litchi stink-bug, exploration of natural resources for promising entomopathogenic fungi is warranted. In this study, two pathogenic fungi were isolated from cadavers of adult T. papillosa . They were identified as Paecilomyces lilacinus and Beauveria bassiana by morphological identification and rDNA-ITS homogeneous analysis. Infection of T. papillosa with B. bassiana and P. lilacinus occurred initially from the antennae, metameres, and inter-segmental membranes. Biological tests showed that the two entomopathogenic fungi induced high mortality in 2 nd and 5 th instar nymphs of T. papillosa . B. bassiana was highly virulent on 2 nd instar nymphs of T. papillosa , with values for cadaver rate, LC 50 and LT 50 of 88.89%, 1.92 × 10 7  conidia/mL and 4.34 days respectively. This study provides two valuable entomopathogenic fungi from T. papillosa . This finding suggests that the highly virulent P. lilacinus and B. bassiana play an important role in the biocontrol of T. papillosa in China. These pathogenic fungi had no pollution or residue risk, and could provide an alternative option for IPM of litchi stink-bug.

The isolation and identification of pathogenic fungi from Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae

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Xiang Meng

2017-10-01

Full Text Available Background Litchi stink-bug, Tessaratoma papillosa Drury (Hemiptera: Tessaratomidae, is one of the most widespread and destructive pest species on Litchi chinensis Sonn and Dimocarpus longan Lour in Southern China. Inappropriate use of chemical pesticides has resulted in serious environmental problems and food pollution. Generating an improved Integrated Pest Management (IPM strategy for litchi stink-bug in orchard farming requires development of an effective biological control agent. Entomopathogenic fungi are regarded as a vital ecological factor in the suppression of pest populations under field conditions. With few effective fungi and pathogenic strains available to control litchi stink-bug, exploration of natural resources for promising entomopathogenic fungi is warranted. Methods & Results In this study, two pathogenic fungi were isolated from cadavers of adult T. papillosa. They were identified as Paecilomyces lilacinus and Beauveria bassiana by morphological identification and rDNA-ITS homogeneous analysis. Infection of T. papillosa with B. bassiana and P. lilacinus occurred initially from the antennae, metameres, and inter-segmental membranes. Biological tests showed that the two entomopathogenic fungi induced high mortality in 2nd and 5th instar nymphs of T. papillosa. B. bassiana was highly virulent on 2nd instar nymphs of T. papillosa, with values for cadaver rate, LC50 and LT50 of 88.89%, 1.92 × 107 conidia/mL and 4.34 days respectively. Discussion This study provides two valuable entomopathogenic fungi from T. papillosa. This finding suggests that the highly virulent P. lilacinus and B. bassiana play an important role in the biocontrol of T. papillosa in China. These pathogenic fungi had no pollution or residue risk, and could provide an alternative option for IPM of litchi stink-bug.

Small proteins of plant-pathogenic fungi secreted during host colonization.

NARCIS (Netherlands)

Rep, M.

2005-01-01

Small proteins secreted by plant pathogenic fungi in their hosts have been implicated in disease symptom development as well as in R-gene mediated disease resistance. Characteristically, this class of proteins shows very limited phylogenetic distribution, possibly due to accelerated evolution

Pathogenicity of Nectriaceous Fungi on Avocado in Australia.

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Parkinson, Louisamarie E; Shivas, Roger G; Dann, Elizabeth K

2017-12-01

Black root rot is a severe disease of young avocado trees in Australia causing black necrotic roots, tree stunting, and leaf drop prior to tree death. Nectriaceous fungi (Nectriaceae, Hypocreales), are commonly isolated from symptomatic roots. This research tested the pathogenicity of 19 isolates from Calonectria, Cylindrocladiella, Dactylonectria, Gliocladiopsis, and Ilyonectria, spp. collected from young avocado trees and other hosts. Glasshouse pathogenicity tests with 'Reed' avocado (Persea americana) seedlings confirmed that Calonectria ilicicola is a severe pathogen of avocado, causing stunting, wilting, and seedling death within 5 weeks of inoculation. Isolates of C. ilicicola from peanut, papaya, and custard apple were also shown to be aggressive pathogens of avocado, demonstrating a broad host range. An isolate of a Calonectria sp. from blueberry and avocado isolates of Dactylonectria macrodidyma, D. novozelandica, D. pauciseptata, and D. anthuriicola caused significant root rot but not stunting within 5 to 9 weeks of inoculation. An isolate of an Ilyonectria sp. from grapevine closely related to Ilyonectria liriodendri, and avocado isolates of Cylindrocladiella pseudoinfestans, Gliocladiopsis peggii, and an Ilyonectria sp. were not pathogenic to avocado.

Oligo-DNA custom macroarray for monitoring major pathogenic and non-pathogenic fungi and bacteria in the phyllosphere of apple trees.

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He, Ying-Hong; Isono, Sayaka; Shibuya, Makoto; Tsuji, Masaharu; Adkar Purushothama, Charith-Raj; Tanaka, Kazuaki; Sano, Teruo

2012-01-01

To monitor the richness in microbial inhabitants in the phyllosphere of apple trees cultivated under various cultural and environmental conditions, we developed an oligo-DNA macroarray for major pathogenic and non-pathogenic fungi and bacteria inhabiting the phyllosphere of apple trees. First, we isolated culturable fungi and bacteria from apple orchards by an agar-plate culture method, and detected 32 fungal and 34 bacterial species. Alternaria, Aureobasidium, Cladosporium, Rhodotorula, Cystofilobasidium, and Epicoccum genera were predominant among the fungi, and Bacillus, Pseudomonas, Sphingomonas, Methylobacterium, and Pantoea genera were predominant among the bacteria. Based on the data, we selected 29 major non-pathogenic and 12 phytopathogenic fungi and bacteria as the targets of macroarray. Forty-one species-specific 40-base pair long oligo-DNA sequences were selected from the nucleotide sequences of rDNA-internal transcribed spacer region for fungi and 16S rDNA for bacteria. The oligo-DNAs were fixed on nylon membrane and hybridized with digoxigenin-labeled cRNA probes prepared for each species. All arrays except those for Alternaria, Bacillus, and their related species, were specifically hybridized. The array was sensitive enough to detect 10(3) CFU for Aureobasidium pullulans and Bacillus cereus. Nucleotide sequencing of 100 each of independent fungal rDNA-ITS and bacterial 16S-rDNA sequences from apple tree was in agreement with the macroarray data obtained using the same sample. Finally, we analyzed the richness in the microbial inhabitants in the samples collected from apple trees in four orchards. Major apple pathogens that cause scab, Alternaria blotch, and Marssonina blotch were detected along with several non-phytopathogenic fungal and bacterial inhabitants. The macroarray technique presented here is a strong tool to monitor the major microbial species and the community structures in the phyllosphere of apple trees and identify key species

Oligo-DNA custom macroarray for monitoring major pathogenic and non-pathogenic fungi and bacteria in the phyllosphere of apple trees.

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Ying-Hong He

Full Text Available BACKGROUND: To monitor the richness in microbial inhabitants in the phyllosphere of apple trees cultivated under various cultural and environmental conditions, we developed an oligo-DNA macroarray for major pathogenic and non-pathogenic fungi and bacteria inhabiting the phyllosphere of apple trees. METHODS AND FINDINGS: First, we isolated culturable fungi and bacteria from apple orchards by an agar-plate culture method, and detected 32 fungal and 34 bacterial species. Alternaria, Aureobasidium, Cladosporium, Rhodotorula, Cystofilobasidium, and Epicoccum genera were predominant among the fungi, and Bacillus, Pseudomonas, Sphingomonas, Methylobacterium, and Pantoea genera were predominant among the bacteria. Based on the data, we selected 29 major non-pathogenic and 12 phytopathogenic fungi and bacteria as the targets of macroarray. Forty-one species-specific 40-base pair long oligo-DNA sequences were selected from the nucleotide sequences of rDNA-internal transcribed spacer region for fungi and 16S rDNA for bacteria. The oligo-DNAs were fixed on nylon membrane and hybridized with digoxigenin-labeled cRNA probes prepared for each species. All arrays except those for Alternaria, Bacillus, and their related species, were specifically hybridized. The array was sensitive enough to detect 10(3 CFU for Aureobasidium pullulans and Bacillus cereus. Nucleotide sequencing of 100 each of independent fungal rDNA-ITS and bacterial 16S-rDNA sequences from apple tree was in agreement with the macroarray data obtained using the same sample. Finally, we analyzed the richness in the microbial inhabitants in the samples collected from apple trees in four orchards. Major apple pathogens that cause scab, Alternaria blotch, and Marssonina blotch were detected along with several non-phytopathogenic fungal and bacterial inhabitants. CONCLUSIONS: The macroarray technique presented here is a strong tool to monitor the major microbial species and the community structures in

Improving ITS sequence data for identification of plant pathogenic fungi

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R. Henrik Nilsson; Kevin D. Hyde; Julia Pawłowska; Martin Ryberg; Leho Tedersoo; Anders Bjørnsgard Aas; Siti A. Alias; Artur Alves; Cajsa Lisa Anderson; Alexandre Antonelli; A. Elizabeth Arnold; Barbara Bahnmann; Mohammad Bahram; Johan Bengtsson-Palme; Anna Berlin; Sara Branco; Putarak Chomnunti; Asha Dissanayake; Rein Drenkhan; Hanna Friberg; Tobias Guldberg Frøslev; Bettina Halwachs; Martin Hartmann; Beatrice Henricot; Ruvishika Jayawardena; Ari Jumpponen; Håvard Kauserud; Sonja Koskela; Tomasz Kulik; Kare Liimatainen; Björn D. Lindahl; Daniel Lindner; Jian-Kui Liu; Sajeewa Maharachchikumbura; Dimuthu Manamgoda; Svante Martinsson; Maria Alice Neves; Tuula Niskanen; Stephan Nylinder; Olinto Liparini Pereira; Danilo Batista Pinho; Teresita M. Porter; Valentin Queloz; Taavi Riit; Marisol Sánchez-García; Filipe de Sousa; Emil Stefańczyk; Mariusz Tadych; Susumu Takamatsu; Qing Tian; Dhanushka Udayanga; Martin Unterseher; Zheng Wang; Saowanee Wikee; Jiye Yan; Ellen Larsson; Karl-Henrik Larsson; Urmas Kõljalg; Kessy Abarenkov

2014-01-01

Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours. These taxa often have complex and poorly understood life cycles, lack observable, discriminatory morphological characters, and may not be amenable to in vitro culturing. As a result, species identification is frequently difficult...

Anti-fungal activity of some medicinal plants on different pathogenic fungi

International Nuclear Information System (INIS)

Hussain, F.; Abid, M.; Farzana, A.; Shaukat, S.; Akbar, M.

2015-01-01

The antifungal activity of different medicinal and locally available plants extracts (leaves, fruit, seeds) which are usually found in the surrounding of fields or in the fields on some fungi were tested in lab conditions. Six different plants were selected for testing these plants were Acacia nilotica (Lamk.) Willd. Azadirachta indica (A.) Juss. Crotalaria juncea L. Eucalyptus camaldulensis Dehnh. Ocimum basilicum L. and Prosopis juliflora (Sw.) Dc. These plants showed antifungal activity against the Aspergillus flavus, A. niger, Fusarium solani, Macrophomina phaseolina and Rhizoctonia solani. These plants crude extracts of leaves showed inhibition activity against the fungi and suppressed the myclial growth. Over all selected plants exhibited moderate type of inhibition against these above mentioned pathogens. Among these plants, Azadirachta indica, Ocimum basilicum and Crotalaria juncea showed the most effective results against the Aspergillus, Fusarium and Rhizoctonia sp. of fungal pathogens. Whereas, Acacia nilotica, Eucalyptus camaldulensis and Prosopis juliflora showed least potential of inhibition against all above mentioned fungal pathogens. It is investigated in present studies that Azadirachta indica, Ocimum basilicum and Crotalaria juncea can be utilized against the management of fungal diseases particularly Aspergillus flavus, A. niger, Fusarium solani, Macrophomina phaseolina and Rhizoctonia solani. (author)

Fungi of the genus Fusarium as pathogens of soybean seedlings

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Joanna Marcinkowska

2013-12-01

Full Text Available Twenty isolates of fungi of the genus Fusarium collected in the period 1980-1982 from various organs of diseased soybean plants were investigated. Eight of them proved pathogenic to soybean seedlings. The species F. culmorum was most numerously represented among the isolated (4 of 8 pathogens. Isolates of F. sambucinum were also pathogenic (2 of 4 and those of F. soloni (1 of 3, too. The only isolate of F. avenaceum also caused seedling blight. Two isolates of F. oxysporum and two of F. arthrosporioides were not pathogenic. Numerous isolates affected seed gernination and one greatly inhibited growth of the infected seedlings. Pathogenicity was tested in the laboratory in Petri plates on isolate cultures and on filter paper imbibed with fungal inoculum and, in the greenhouse on a peat and perlite substrate. The degree of infection and the character of the disease symptoms depended on the experimental conditions. The results of experiments in plates and in the greenhouse supplemented one another.

Entomopathogenic Fungi: New Insights into Host-Pathogen Interactions.

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Butt, T M; Coates, C J; Dubovskiy, I M; Ratcliffe, N A

2016-01-01

Although many insects successfully live in dangerous environments exposed to diverse communities of microbes, they are often exploited and killed by specialist pathogens. Studies of host-pathogen interactions (HPI) provide valuable insights into the dynamics of the highly aggressive coevolutionary arms race between entomopathogenic fungi (EPF) and their arthropod hosts. The host defenses are designed to exclude the pathogen or mitigate the damage inflicted while the pathogen responds with immune evasion and utilization of host resources. EPF neutralize their immediate surroundings on the insect integument and benefit from the physiochemical properties of the cuticle and its compounds that exclude competing microbes. EPF also exhibit adaptations aimed at minimizing trauma that can be deleterious to both host and pathogen (eg, melanization of hemolymph), form narrow penetration pegs that alleviate host dehydration and produce blastospores that lack immunogenic sugars/enzymes but facilitate rapid assimilation of hemolymph nutrients. In response, insects deploy an extensive armory of hemocytes and macromolecules, such as lectins and phenoloxidase, that repel, immobilize, and kill EPF. New evidence suggests that immune bioactives work synergistically (eg, lysozyme with antimicrobial peptides) to combat infections. Some proteins, including transferrin and apolipophorin III, also demonstrate multifunctional properties, participating in metabolism, homeostasis, and pathogen recognition. This review discusses the molecular intricacies of these HPI, highlighting the interplay between immunity, stress management, and metabolism. Increased knowledge in this area could enhance the efficacy of EPF, ensuring their future in integrated pest management programs. Copyright © 2016 Elsevier Inc. All rights reserved.

Antifungal activity of aloe vera gel against plant pathogenic fungi

International Nuclear Information System (INIS)

Sitara, U.; Hassan, N.; Naseem, J.

2011-01-01

Aloe vera gel extracted from the Aloe vera leaves was evaluated for their antifungal activity at the rate of 0.15%, 0.25% and 0.35% concentration against five plants pathogenic fungi viz., Aspergillus niger, Aspergillus flavus, Alternaria alternata, Drechslera hawaiensis and Penicillum digitatum 0.35% concentration Aloe vera gel completely inhibited the growth of Drechslera hawaiensis and Alternaria alternata. (author)

Calcium homeostasis and signaling in fungi and their relevance for pathogenicity of yeasts and filamentous fungi

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Renata Tisi

2016-09-01

Full Text Available Though fungi show peculiarities in the purposes and specific traits of calcium signaling pathways, the general scheme and the most important players are well conserved if compared to higher eukaryotes. This provides a powerful opportunity either to investigate shared features using yeast as a model or to exploit fungal specificities as potential targets for antifungal therapies. The sequenced genomes from yeast Saccharomyces cerevisiae, Schizosaccharomyces pombe and the filamentous fungus Neurospora crassa were already published more than ten years ago. More recently the genome sequences of filamentous fungi of Aspergillus genus, some of which threatening pathogens, and dimorphic fungi Ustilago maydis were published, giving the chance to identify several proteins involved in calcium signaling based on their homology to yeast or mammalian counterparts. Nonetheless, unidentified calcium transporters are still present in these organisms which await to be molecularly characterized. Despite the relative simplicity in yeast calcium machinery and the availability of sophisticated molecular tools, in the last years, a number of new actors have been identified, albeit not yet fully characterized. This review will try to describe the state of the art in calcium channels and calcium signaling knowledge in yeast, with particular attention to the relevance of this knowledge with respect to pathological fungi.

The modular nature of dendritic cell responses to commensal and pathogenic fungi.

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Lisa Rizzetto

Full Text Available The type of adaptive immune response following host-fungi interaction is largely determined at the level of the antigen-presenting cells, and in particular by dendritic cells (DCs. The extent to which transcriptional regulatory events determine the decision making process in DCs is still an open question. By applying the highly structured DC-ATLAS pathways to analyze DC responses, we classified the various stimuli by revealing the modular nature of the different transcriptional programs governing the recognition of either pathogenic or commensal fungi. Through comparison of the network parts affected by DC stimulation with fungal cells and purified single agonists, we could determine the contribution of each receptor during the recognition process. We observed that initial recognition of a fungus creates a temporal window during which the simultaneous recruitment of cell surface receptors can intensify, complement and sustain the DC activation process. The breakdown of the response to whole live cells, through the purified components, showed how the response to invading fungi uses a set of specific modules. We find that at the start of fungal recognition, DCs rapidly initiate the activation process. Ligand recognition is further enhanced by over-expression of the receptor genes, with a significant correspondence between gene expression and protein levels and function. Then a marked decrease in the receptor levels follows, suggesting that at this moment the DC commits to a specific fate. Overall our pathway based studies show that the temporal window of the fungal recognition process depends on the availability of ligands and is different for pathogens and commensals. Modular analysis of receptor and signalling-adaptor expression changes, in the early phase of pathogen recognition, is a valuable tool for rapid and efficient dissection of the pathogen derived components that determine the phenotype of the DC and thereby the type of immune response

Contribution of proteomics to the study of plant pathogenic fungi.

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Gonzalez-Fernandez, Raquel; Jorrin-Novo, Jesus V

2012-01-01

Phytopathogenic fungi are one of the most damaging plant parasitic organisms, and can cause serious diseases and important yield losses in crops. The study of the biology of these microorganisms and the interaction with their hosts has experienced great advances in recent years due to the development of moderm, holistic and high-throughput -omic techniques, together with the increasing number of genome sequencing projects and the development of mutants and reverse genetics tools. We highlight among these -omic techniques the importance of proteomics, which has become a relevant tool in plant-fungus pathosystem research. Proteomics intends to identify gene products with a key role in pathogenicity and virulence. These studies would help in the search of key protein targets and in the development of agrochemicals, which may open new ways for crop disease diagnosis and protection. In this review, we made an overview on the contribution of proteomics to the knowledge of life cycle, infection mechanisms, and virulence of the plant pathogenic fungi. Data from current, innovative literature, according to both methodological and experimental systems, were summarized and discussed. Specific sections were devoted to the most studied fungal phytopathogens: Botrytis cinerea, Sclerotinia sclerotiorum, and Fusarium graminearum.

Apyrase inhibitors enhance the ability of diverse fungicides to inhibit the growth of different plant-pathogenic fungi.

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Kumar Tripathy, Manas; Weeraratne, Gayani; Clark, Greg; Roux, Stanley J

2017-09-01

A previous study has demonstrated that the treatment of Arabidopsis plants with chemical inhibitors of apyrase enzymes increases their sensitivity to herbicides. In this study, we found that the addition of the same or related apyrase inhibitors could potentiate the ability of different fungicides to inhibit the growth of five different pathogenic fungi in plate growth assays. The growth of all five fungi was partially inhibited by three commonly used fungicides: copper octanoate, myclobutanil and propiconazole. However, when these fungicides were individually tested in combination with any one of four different apyrase inhibitors (AI.1, AI.10, AI.13 or AI.15), their potency to inhibit the growth of five fungal pathogens was increased significantly relative to their application alone. The apyrase inhibitors were most effective in potentiating the ability of copper octanoate to inhibit fungal growth, and least effective in combination with propiconazole. Among the five pathogens assayed, that most sensitive to the fungicide-potentiating effects of the inhibitors was Sclerotinia sclerotiorum. Overall, among the 60 treatment combinations tested (five pathogens, four apyrase inhibitors, three fungicides), the addition of apyrase inhibitors increased significantly the sensitivity of fungi to the fungicide treatments in 53 of the combinations. Consistent with their predicted mode of action, inhibitors AI.1, AI.10 and AI.13 each increased the level of propiconazole retained in one of the fungi, suggesting that they could partially block the ability of efflux transporters to remove propiconazole from these fungi. © 2016 BSPP AND JOHN WILEY & SONS LTD.

SCREENING OF FLUORESCENT RHIZOBACTERIA FOR THE BIOCONTROL OF SOILBORNE PLANT PATHOGENIC FUNGI

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ANELISE DIAS

2014-01-01

Full Text Available The biocontrol of soilborne plant pathogens represents a promising approach from the environ- mental and practical points of view. Fluorescent pseudomonad rhizobacteria are well known by their antagonis- tic capacity towards several plant pathogens due to a diversity of antimicrobial metabolites they produce. This study was conceived to select and characterize rhizobacteria having antagonistic potential towards the patho- genic fungi Rhizoctonia solani and Sclerotium rolfsii. A total of 94 bacterial strains isolated from the rhizospheres of four vegetable species under organic cultivation were evaluated. Twenty-two strains which predominate in lettuce and rudbeckia rhizospheres showed identical biochemical profiles to Pseudomonas fluo- rescens, while in kale and parsley rhizospheres identical profiles to Pseudomonas putida (subgroups A and B strains prevailed. Two types of antagonism were verified in vitro and defined as competition and inhibition of mycelial growth. Sixty percent of the evaluated strains showed antagonistic potential and, among those, 24 strains expressed antagonism to both target fungi, with P. fluorescens being the most representative bacterial species. This work clearly identified a number of strains with potential for use as plant growth-promoting and biocontrol of the two soilborne fungal pathogens in vegetable crops production systems.

Effect of root exudates of various plants on composition of bacteria and fungi communities with special regard to pathogenic soil-borne fungi

OpenAIRE

Danuta Piętka; Elżbieta Patkowska

2013-01-01

The purpose of the studies conducted in the years 1996 - 1998 was to determine the composition of bacteria and fungi populations in the rhizosphere of winter wheat, spring wheat, soybean and potato, and in non-rhizosphere soil. Besides, the effect of root exudates of these plants on the formation of pathogenic fungi communities was established. The microbiological analysis showed that the greatest tolal number of bacteria was found in the rhizospheres of potato and soybean, and the lowest num...

Contribution to the knowledge of pathogenic fungi of spiders in Argentina. Southernmost record in the world.

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Manfrino, Romina G; González, Alda; Barneche, Jorge; Tornesello Galván, Julieta; Hywell-Jones, Nigel; López Lastra, Claudia C

The aim of this study was to identify entomopathogenic fungi infecting spiders (Araneae) in a protected area of Buenos Aires province, Argentina. The Araneae species identified was Stenoterommata platensis. The pathogens identified were Lecanicillium aphanocladii Zare & W. Gams, Purpureocillium lilacinum (Thom) Luangsa-ard, Houbraken, Hywel Jones & Samson and Ophiocordyceps caloceroides (Berk & M.A. Curtis). This study constitutes the southernmost records in the world and contributes to expanding the knowledge of the biodiversity of pathogenic fungi of spiders in Argentina. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Conserved Responses in a War of Small Molecules between a Plant-Pathogenic Bacterium and Fungi.

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Spraker, Joseph E; Wiemann, Philipp; Baccile, Joshua A; Venkatesh, Nandhitha; Schumacher, Julia; Schroeder, Frank C; Sanchez, Laura M; Keller, Nancy P

2018-05-22

Small-molecule signaling is one major mode of communication within the polymicrobial consortium of soil and rhizosphere. While microbial secondary metabolite (SM) production and responses of individual species have been studied extensively, little is known about potentially conserved roles of SM signals in multilayered symbiotic or antagonistic relationships. Here, we characterize the SM-mediated interaction between the plant-pathogenic bacterium Ralstonia solanacearum and the two plant-pathogenic fungi Fusarium fujikuroi and Botrytis cinerea We show that cellular differentiation and SM biosynthesis in F. fujikuroi are induced by the bacterially produced lipopeptide ralsolamycin (synonym ralstonin A). In particular, fungal bikaverin production is induced and preferentially accumulates in fungal survival spores (chlamydospores) only when exposed to supernatants of ralsolamycin-producing strains of R. solanacearum Although inactivation of bikaverin biosynthesis moderately increases chlamydospore invasion by R. solanacearum , we show that other metabolites such as beauvericin are also induced by ralsolamycin and contribute to suppression of R. solanacearum growth in vitro Based on our findings that bikaverin antagonizes R. solanacearum and that ralsolamycin induces bikaverin biosynthesis in F. fujikuroi , we asked whether other bikaverin-producing fungi show similar responses to ralsolamycin. Examining a strain of B. cinerea that horizontally acquired the bikaverin gene cluster from Fusarium , we found that ralsolamycin induced bikaverin biosynthesis in this fungus. Our results suggest that conservation of microbial SM responses across distantly related fungi may arise from horizontal transfer of protective gene clusters that are activated by conserved regulatory cues, e.g., a bacterial lipopeptide, providing consistent fitness advantages in dynamic polymicrobial networks. IMPORTANCE Bacteria and fungi are ubiquitous neighbors in many environments, including

Histone deacetylases: revealing the molecular base of dimorphism in pathogenic fungi

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Alberto Elías-Villalobos

2015-11-01

Full Text Available Fungi, as every living organism, interact with the external world and have to adapt to its fluctuations. For pathogenic fungi, such interaction involves adapting to the hostile environment of their host. Survival depends on the capacity of fungi to detect and respond to external stimuli, which is achieved through a tight and efficient genetic control. Chromatin modifications represent a well-known layer of regulation that controls gene expression in response to environmental signals. However, less is known about the chromatin modifications that are involved in fungal virulence and the specific cues and signalling pathways that target chromatin modifications to specific genes. In a recently published study, our research group identified one such regulatory pathway. We demonstrated that the histone deacetylase (HDAC Hos2 is involved in yeast-to-hyphal transition (dimorphism and it is associated with the virulence of the maize pathogen Ustilago maydis, the causative agent of smut disease in corn. Hos2 activates mating-type genes by directly binding to their gene bodies. Furthermore, Hos2 acts downstream of the nutrient-sensing cyclic AMP-Protein Kinase A pathway. We also found that another HDAC, Clr3, contributes to this regulation, possibly in cooperation with Hos2. As a whole, our data suggest that there is a direct link between changes in the environment and acetylation of nucleosomes within certain genes. We propose that histone acetylation is critical to the proper timing and induction of transcription of the genes encoding factors that coordinate changes in morphology with pathogenesis.

Identifying and naming plant-pathogenic fungi: past, present, and future.

Science.gov (United States)

Crous, Pedro W; Hawksworth, David L; Wingfield, Michael J

2015-01-01

Scientific names are crucial in communicating knowledge about fungi. In plant pathology, they link information regarding the biology, host range, distribution, and potential risk. Our understanding of fungal biodiversity and fungal systematics has undergone an exponential leap, incorporating genomics, web-based systems, and DNA data for rapid identification to link species to metadata. The impact of our ability to recognize hitherto unknown organisms on plant pathology and trade is enormous and continues to grow. Major challenges for phytomycology are intertwined with the Genera of Fungi project, which adds DNA barcodes to known biodiversity and corrects the application of old, established names via epi- or neotypification. Implementing the one fungus-one name system and linking names to validated type specimens, cultures, and reference sequences will provide the foundation on which the future of plant pathology and the communication of names of plant pathogens will rest.

A review on the inhibitory potential of Nigella sativa against pathogenic and toxigenic fungi.

Science.gov (United States)

Shokri, Hojjatollah

2016-01-01

Nigella sativa (N. sativa) grows in various parts of the world, particularly in Iran. It has been traditionally used as a folk remedy to treat a number of diseases. The seeds of this plant contain moisture, proteins, carbohydrates, crude fiber, alkaloids, saponins, ash, fixed oils and essential oil. The major components of the essential oil are thymoquinone, p-cymene, trans-anethole, 2-methyl-5(1-methyl ethyl)-Bicyclo[3.1.0]hex-2-en and γ-terpinene. So far, several pharmacological effects such as anti-oxidant, anti-inflammatory, anti-cancer and anti-microbial have been reported for N. sativa or its active compounds. Thymoquinone, thymohydroquinone and thymol are the most active constituents which have different beneficial properties. The oil, extracts and some of N. sativa active components possessed moderate in vitro and in vivo inhibitory activity against pathogenic yeasts, dermatophytes, non-dermatophytic filamentous fungi and aflatoxin-producing fungi. The main morphological changes of pathogenic and toxigenic fungi treated with N. sativa oil were observed in the cell wall, plasma membrane and membranous organelles, particularly in the nuclei and mitochondria. Although this review represents first step in the search for a new anti-fungal drug, the full potential of N. sativa as a fungitoxic agent has not been exploited and necessitates further investigations.

Swainsonine Biosynthesis Genes in Diverse Symbiotic and Pathogenic Fungi

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Daniel Cook

2017-06-01

Full Text Available Swainsonine—a cytotoxic fungal alkaloid and a potential cancer therapy drug—is produced by the insect pathogen and plant symbiont Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glory symbiont belonging to order Chaetothyriales. Genome sequence analyses revealed that these fungi share orthologous gene clusters, designated “SWN,” which included a multifunctional swnK gene comprising predicted adenylylation and acyltransferase domains with their associated thiolation domains, a β-ketoacyl synthase domain, and two reductase domains. The role of swnK was demonstrated by inactivating it in M. robertsii through homologous gene replacement to give a ∆swnK mutant that produced no detectable swainsonine, then complementing the mutant with the wild-type gene to restore swainsonine biosynthesis. Other SWN cluster genes were predicted to encode two putative hydroxylases and two reductases, as expected to complete biosynthesis of swainsonine from the predicted SwnK product. SWN gene clusters were identified in six out of seven sequenced genomes of Metarhzium species, and in all 15 sequenced genomes of Arthrodermataceae, a family of fungi that cause athlete’s foot and ringworm diseases in humans and other mammals. Representative isolates of all of these species were cultured, and all Metarhizium spp. with SWN clusters, as well as all but one of the Arthrodermataceae, produced swainsonine. These results suggest a new biosynthetic hypothesis for this alkaloid, extending the known taxonomic breadth of swainsonine producers to at least four orders of Ascomycota, and suggest that swainsonine has roles in mutualistic symbioses and diseases of plants and animals.

The pathogenic fungi in mushroom cultivation of Agaricus bisporus (Lange.) Imbach.

OpenAIRE

Agata Tekiela

2012-01-01

The research was conducted in a mushroom growing facility located near Rzeszów, consisting of three production cycles. The number and composition of microorganisms which accompany the mushroom cultivation depended on the healthiness of: the compost, casing and spawn of Agaricus bisporus. The presence of pathogenic fungi in the cultivation halls at the beginning of the production cycle is a serious threat to the cultivation of common mushroom because their rapid development shortens the span o...

The pathogenic fungi in mushroom cultivation of Agaricus bisporus (Lange. Imbach.

Directory of Open Access Journals (Sweden)

Agata Tekiela

2012-12-01

Full Text Available The research was conducted in a mushroom growing facility located near Rzeszów, consisting of three production cycles. The number and composition of microorganisms which accompany the mushroom cultivation depended on the healthiness of: the compost, casing and spawn of Agaricus bisporus. The presence of pathogenic fungi in the cultivation halls at the beginning of the production cycle is a serious threat to the cultivation of common mushroom because their rapid development shortens the span of fruiting body harvests.

Inhibition of in vitro growth of soil-borne pathogens by compost-inhabiting indigenous bacteria and fungi

International Nuclear Information System (INIS)

Ramzan, N.; Noreen, N.; Shahzad, S.

2014-01-01

During the present studies, compost-inhabiting microorganisms including 44 fungi and 15 bacteria isolated from different compost samples were evaluated for their in vitro efficacy against soil-borne pathogens viz., Fusarium solani, Macrophomina phaseolina, Pythium aphanidermatum, Rhizoctonia solani, and Sclerotium rolfsii. Compost inhabiting microbes like Trichoderma harzianum, T. virens, Bacillus cereus, B. pumilus, B. subtilis, Micrococcus varians and Pseudomonas fluorescens were found to inhibit all the test pathogens. Acrophialophora fusispora and Penicillium citrinum reduced the mycelial growth of all the test pathogens except Sclerotium rolfsii. Bacillus licheniformis and Bacillus megaterium showed biocontrol activity against all the pathogens except Rhizoctonia solani. Trichoderma harzianum parasitized mycelia of all the tested pathogens and produced coiling around the mycelium. (author)

First survey on ecological host range of aphid pathogenic fungi (Phylum Entomophthoromycota) in Tunisia

DEFF Research Database (Denmark)

Ben Fekih, Ibtissem; Boukhris-Bouhachem, Sonia; Allagui, Mohamed Bechir

2015-01-01

Summary. The natural occurrence of fungal pathogens of aphids and their ecological host range was investigated in Tunisia from 2009 to 2012. The survey focused on aphid infesting different crops and weeds and included 10 different aphid species. Samples were collected from eight agricultural crops...... (Entomophthorales: Ancylistaceae) and Neozygites fresenii (Neozygitales: Neozygitaceae). The occurrence of entomophthoralean fungi depended on the sampling area, the bioclimatic zone, and aphid species. P. neoaphidis and E. planchoniana were the predominant pathogens infecting a wide range of aphid species whereas...... sites belonging to three different bioclimatic zones. Four pathogens from the phylum Entomophthoromycota were found to occur naturally in Tunisian ecosystems: Pandora neoaphidis (Entomophthorales: Entomophthoraceae), Entomophthora planchoniana (Entomophthorales: Entomophthoraceae), Conidiobolus obscurus...

Evolution of structural diversity of trichothecenes, a family of toxins produced by plant pathogenic and entomopathogenic fungi.

Science.gov (United States)

Proctor, Robert H; McCormick, Susan P; Kim, Hye-Seon; Cardoza, Rosa E; Stanley, April M; Lindo, Laura; Kelly, Amy; Brown, Daren W; Lee, Theresa; Vaughan, Martha M; Alexander, Nancy J; Busman, Mark; Gutiérrez, Santiago

2018-04-01

Trichothecenes are a family of terpenoid toxins produced by multiple genera of fungi, including plant and insect pathogens. Some trichothecenes produced by the fungus Fusarium are among the mycotoxins of greatest concern to food and feed safety because of their toxicity and frequent occurrence in cereal crops, and trichothecene production contributes to pathogenesis of some Fusarium species on plants. Collectively, fungi produce over 150 trichothecene analogs: i.e., molecules that share the same core structure but differ in patterns of substituents attached to the core structure. Here, we carried out genomic, phylogenetic, gene-function, and analytical chemistry studies of strains from nine fungal genera to identify genetic variation responsible for trichothecene structural diversity and to gain insight into evolutionary processes that have contributed to the variation. The results indicate that structural diversity has resulted from gain, loss, and functional changes of trichothecene biosynthetic (TRI) genes. The results also indicate that the presence of some substituents has arisen independently in different fungi by gain of different genes with the same function. Variation in TRI gene duplication and number of TRI loci was also observed among the fungi examined, but there was no evidence that such genetic differences have contributed to trichothecene structural variation. We also inferred ancestral states of the TRI cluster and trichothecene biosynthetic pathway, and proposed scenarios for changes in trichothecene structures during divergence of TRI cluster homologs. Together, our findings provide insight into evolutionary processes responsible for structural diversification of toxins produced by pathogenic fungi.

Challenges and Strategies for Proteome Analysis of the Interaction of Human Pathogenic Fungi with Host Immune Cells.

Science.gov (United States)

Krüger, Thomas; Luo, Ting; Schmidt, Hella; Shopova, Iordana; Kniemeyer, Olaf

2015-12-14

Opportunistic human pathogenic fungi including the saprotrophic mold Aspergillus fumigatus and the human commensal Candida albicans can cause severe fungal infections in immunocompromised or critically ill patients. The first line of defense against opportunistic fungal pathogens is the innate immune system. Phagocytes such as macrophages, neutrophils and dendritic cells are an important pillar of the innate immune response and have evolved versatile defense strategies against microbial pathogens. On the other hand, human-pathogenic fungi have sophisticated virulence strategies to counteract the innate immune defense. In this context, proteomic approaches can provide deeper insights into the molecular mechanisms of the interaction of host immune cells with fungal pathogens. This is crucial for the identification of both diagnostic biomarkers for fungal infections and therapeutic targets. Studying host-fungal interactions at the protein level is a challenging endeavor, yet there are few studies that have been undertaken. This review draws attention to proteomic techniques and their application to fungal pathogens and to challenges, difficulties, and limitations that may arise in the course of simultaneous dual proteome analysis of host immune cells interacting with diverse morphotypes of fungal pathogens. On this basis, we discuss strategies to overcome these multifaceted experimental and analytical challenges including the viability of immune cells during co-cultivation, the increased and heterogeneous protein complexity of the host proteome dynamically interacting with the fungal proteome, and the demands on normalization strategies in terms of relative quantitative proteome analysis.

Effects of neolignans from the stem bark of Magnolia obovata on plant pathogenic fungi.

Science.gov (United States)

Choi, N H; Choi, G J; Min, B-S; Jang, K S; Choi, Y H; Kang, M S; Park, M S; Choi, J E; Bae, B K; Kim, J-C

2009-06-01

To characterize antifungal principles from the methanol extract of Magnolia obovata and to evaluate their antifungal activities against various plant pathogenic fungi. Four neolignans were isolated from stem bark of M. obovata as antifungal principles and identified as magnolol, honokiol, 4-methoxyhonokiol and obovatol. In mycelial growth inhibition assay, both magnolol and honokiol displayed more potent antifungal activity than 4-methoxyhonokiol and obovatol. Both magnolol and honokiol showed similar in vivo antifungal spectrum against seven plant diseases tested; both compounds effectively suppressed the development of rice blast, tomato late blight, wheat leaf rust and red pepper anthracnose. 4-Methoxyhonokiol and obovatol were highly active to only rice blast and wheat leaf rust respectively. The extract of M. obovata and four neolignans had potent in vivo antifungal activities against plant pathogenic fungi. Neolignans from Magnolia spp. can be used and suggested as a novel antifungal lead compound for the development of new fungicide and directly as a natural fungicide for the control of plant diseases such as rice blast and wheat leaf rust.

Peptide-Like Nylon-3 Polymers with Activity against Phylogenetically Diverse, Intrinsically Drug-Resistant Pathogenic Fungi.

Science.gov (United States)

Rank, Leslie A; Walsh, Naomi M; Lim, Fang Yun; Gellman, Samuel H; Keller, Nancy P; Hull, Christina M

2018-01-01

Understanding the dimensions of fungal diversity has major implications for the control of diseases in humans, plants, and animals and in the overall health of ecosystems on the planet. One ancient evolutionary strategy organisms use to manage interactions with microbes, including fungi, is to produce host defense peptides (HDPs). HDPs and their synthetic analogs have been subjects of interest as potential therapeutic agents. Due to increases in fungal disease worldwide, there is great interest in developing novel antifungal agents. Here we describe activity of polymeric HDP analogs against fungi from 18 pathogenic genera composed of 41 species and 72 isolates. The synthetic polymers are members of the nylon-3 family (poly-β-amino acid materials). Three different nylon-3 polymers show high efficacy against surprisingly diverse fungi. Across the phylogenetic spectrum (with the exception of Aspergillus species), yeasts, dermatophytes, dimorphic fungi, and molds were all sensitive to the effects of these polymers. Even fungi intrinsically resistant to current antifungal drugs, such as the causative agents of mucormycosis ( Rhizopus spp.) and those with acquired resistance to azole drugs, showed nylon-3 polymer sensitivity. In addition, the emerging pathogens Pseudogymnoascus destructans (cause of white nose syndrome in bats) and Candida auris (cause of nosocomial infections of humans) were also sensitive. The three nylon-3 polymers exhibited relatively low toxicity toward mammalian cells. These findings raise the possibility that nylon-3 polymers could be useful against fungi for which there are only limited and/or no antifungal agents available at present. IMPORTANCE Fungi reside in all ecosystems on earth and impart both positive and negative effects on human, plant, and animal health. Fungal disease is on the rise worldwide, and there is a critical need for more effective and less toxic antifungal agents. Nylon-3 polymers are short, sequence random, poly

Antifungal Activity of Decyl Gallate against Several Species of Pathogenic Fungi

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Ana Carolina Alves de Paula e Silva

2014-01-01

Full Text Available This work aims to demonstrate that the gallic acid structure modification to the decyl gallate (G14 compound contributed to increase the antifungal activity against several species of pathogenic fungi, mainly, Candida spp., Cryptococcus spp., Paracoccidioides spp., and Histoplasma capsulatum, according to standardized microdilution method described by Clinical Laboratory Standard Institute (CLSI documents. Moreover this compound has a particularly good selectivity index value, which makes it an excellent candidate for broad-spectrum antifungal prototype and encourages the continuation of subsequent studies for the discovery of its mechanism of action.

FungiDB: An Integrated Bioinformatic Resource for Fungi and Oomycetes

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Evelina Y. Basenko

2018-03-01

Full Text Available FungiDB (fungidb.org is a free online resource for data mining and functional genomics analysis for fungal and oomycete species. FungiDB is part of the Eukaryotic Pathogen Genomics Database Resource (EuPathDB, eupathdb.org platform that integrates genomic, transcriptomic, proteomic, and phenotypic datasets, and other types of data for pathogenic and nonpathogenic, free-living and parasitic organisms. FungiDB is one of the largest EuPathDB databases containing nearly 100 genomes obtained from GenBank, Aspergillus Genome Database (AspGD, The Broad Institute, Joint Genome Institute (JGI, Ensembl, and other sources. FungiDB offers a user-friendly web interface with embedded bioinformatics tools that support custom in silico experiments that leverage FungiDB-integrated data. In addition, a Galaxy-based workspace enables users to generate custom pipelines for large-scale data analysis (e.g., RNA-Seq, variant calling, etc.. This review provides an introduction to the FungiDB resources and focuses on available features, tools, and queries and how they can be used to mine data across a diverse range of integrated FungiDB datasets and records.

The Herbivore-Induced Plant Volatiles Methyl Salicylate and Menthol Positively affect Growth and Pathogenicity of Entomopathogenic Fungi

Science.gov (United States)

Lin, Yongwen; Qasim, Muhammad; Hussain, Mubasher; Akutse, Komivi Senyo; Avery, Pasco Bruce; Dash, Chandra Kanta; Wang, Liande

2017-01-01

Some herbivore-induced-plant volatiles (HIPVs) compounds are vital for the functioning of an ecosystem, by triggering multi-trophic interactions for natural enemies, plants and herbivores. However, the effect of these chemicals, which play a crucial role in regulating the multi-trophic interactions between plant-herbivore-entomopathogenic fungi, is still unknown. To fill this scientific gap, we therefore investigated how these chemicals influence the entomopathogenic fungi growth and efficacy. In this study, Lipaphis erysimi induced Arabidopsis thaliana HIPVs were collected using headspace system and detected with GC-MS, and then analyzed the effects of these HIPVs chemicals on Lecanicillium lecanii strain V3450. We found that the HIPVs menthol and methyl salicylate at 1 and 10 nmol·ml-1 improved many performance aspects of the fungus, such as germination, sporulation, appressorial formation as well as its pathogenicity and virulence. These findings are not only important for understanding the multi-trophic interactions in an ecosystem, but also would contribute for developing new and easier procedures for conidial mass production as well as improve the pathogenicity and virulence of entomopathogenic fungi in biological pest management strategies.

Antimicrobial activity of broccoli (Brassica oleracea var. italica) cultivar Avenger against pathogenic bacteria, phytopathogenic filamentous fungi and yeast.

Science.gov (United States)

Pacheco-Cano, R D; Salcedo-Hernández, R; López-Meza, J E; Bideshi, D K; Barboza-Corona, J E

2018-01-01

The objective of this study was to show whether the edible part of broccoli has antibacterial and antifungal activity against micro-organism of importance in human health and vegetable spoilage, and to test if this effect was partially due to antimicrobial peptides (AMPs). Crude extracts were obtained from florets and stems of broccoli cultivar Avenger and the inhibitory effect was demonstrated against pathogenic bacteria (Bacillus cereus, Staphylococcus xylosus, Staphylococcus aureus, Shigella flexneri, Shigella sonnei, Proteus vulgaris), phytopathogenic fungi (Colletotrichum gloeosporioides, Asperigillus niger) and yeasts (Candida albicans and Rhodotorula sp.). It was shown that samples treated with proteolytic enzymes had a reduction of approximately 60% in antibacterial activity against Staph. xylosus, suggesting that proteinaceous compounds might play a role in the inhibitory effect. Antimicrobial components in crude extracts were thermoresistant and the highest activity was observed under acidic conditions. It was shown that antifungal activity of broccoli's crude extracts might not be attributed to chitinases. Organic broccoli cultivar Avenger has antimicrobial activity against pathogenic bacteria, yeast and phytophatogenic fungi. Data suggest that this effect is partially due to AMPs. Broccoli's crude extracts have activity not only against pathogenic bacteria but also against phytophatogenic fungi of importance in agriculture. We suggest for first time that the inhibitory effect is probably due to AMPs. © 2017 The Society for Applied Microbiology.

Poly(lactic-co-glycolic) acid nanoparticles uptake by Vitis vinifera and grapevine-pathogenic fungi

International Nuclear Information System (INIS)

Valletta, Alessio; Chronopoulou, Laura; Palocci, Cleofe; Baldan, Barbara; Donati, Livia; Pasqua, Gabriella

2014-01-01

Poly(lactic-co-glycolic) acid (PLGA)-based NPs are currently considered among the most promising drug carriers, nevertheless their use in plants has never been investigated. In this work, for the first time, we demonstrated the ability of PLGA NPs to cross the plant cell wall and membrane of Vitis vinifera cell cultures and grapevine-pathogenic fungi. By means of fluorescence microscopy, we established that PLGA NPs can enter in grapevine leaf tissues through stomata openings and that they can be absorbed by the roots and transported to the shoot through vascular tissues. TEM analysis on cultured cells showed that NPs ≤ 50 nm could enter cells, while bigger ones remained attached to the cell wall. Viability tests demonstrated that PLGA NPs were not cytotoxic for V. vinifera-cultured cells. The cellular uptake of PLGA NPs by some important grapevine-pathogenic fungi has also been observed, thus suggesting that PLGA NPs could be used to deliver antifungal compounds within fungal cells. Overall the results reported suggest that such NPs may play a key role in future developments of agrobiotechnologies, as it is currently happening in biomedicine

Poly(lactic-co-glycolic) acid nanoparticles uptake by Vitis vinifera and grapevine-pathogenic fungi

Energy Technology Data Exchange (ETDEWEB)

Valletta, Alessio [“Sapienza” University of Rome, Department of Environmental Biology (Italy); Chronopoulou, Laura; Palocci, Cleofe, E-mail: cleofe.palocci@uniroma1.it [“Sapienza” University of Rome, Department of Chemistry (Italy); Baldan, Barbara [University of Padua, Department of Biology (Italy); Donati, Livia; Pasqua, Gabriella [“Sapienza” University of Rome, Department of Environmental Biology (Italy)

2014-12-15

Poly(lactic-co-glycolic) acid (PLGA)-based NPs are currently considered among the most promising drug carriers, nevertheless their use in plants has never been investigated. In this work, for the first time, we demonstrated the ability of PLGA NPs to cross the plant cell wall and membrane of Vitis vinifera cell cultures and grapevine-pathogenic fungi. By means of fluorescence microscopy, we established that PLGA NPs can enter in grapevine leaf tissues through stomata openings and that they can be absorbed by the roots and transported to the shoot through vascular tissues. TEM analysis on cultured cells showed that NPs ≤ 50 nm could enter cells, while bigger ones remained attached to the cell wall. Viability tests demonstrated that PLGA NPs were not cytotoxic for V. vinifera-cultured cells. The cellular uptake of PLGA NPs by some important grapevine-pathogenic fungi has also been observed, thus suggesting that PLGA NPs could be used to deliver antifungal compounds within fungal cells. Overall the results reported suggest that such NPs may play a key role in future developments of agrobiotechnologies, as it is currently happening in biomedicine.

Filamentous Fungi.

Science.gov (United States)

Powers-Fletcher, Margaret V; Kendall, Brian A; Griffin, Allen T; Hanson, Kimberly E

2016-06-01

Filamentous mycoses are often associated with significant morbidity and mortality. Prompt diagnosis and aggressive treatment are essential for good clinical outcomes in immunocompromised patients. The host immune response plays an essential role in determining the course of exposure to potential fungal pathogens. Depending on the effectiveness of immune response and the burden of organism exposure, fungi can either be cleared or infection can occur and progress to a potentially fatal invasive disease. Nonspecific cellular immunity (i.e., neutrophils, natural killer [NK] cells, and macrophages) combined with T-cell responses are the main immunologic mechanisms of protection. The most common potential mold pathogens include certain hyaline hyphomycetes, endemic fungi, the Mucorales, and some dematiaceous fungi. Laboratory diagnostics aimed at detecting and differentiating these organisms are crucial to helping clinicians make informed decisions about treatment. The purpose of this chapter is to provide an overview of the medically important fungal pathogens, as well as to discuss the patient characteristics, antifungal-therapy considerations, and laboratory tests used in current clinical practice for the immunocompromised host.

Comparative efficacy and pathogenicity of keratinophilic soil fungi against Culex quinquefasciatus larvae.

Science.gov (United States)

Mohanty, Suman Sundar; Prakash, Soam

2010-09-01

Out of seven fungal species belonging to four genera isolated from pond and wallow soils using feathers of Pavo cristatus as bait, four species viz., Aspergillus flavus, Aspergillus niger, Chrysosporium pseudomerdarium and Trichophyton ajelloi were most frequent. Chrysosporium and Trichophyton spp. were more pathogenic on Culex quinquefasciatus larvae than Aspergillus and Penicillium. The bioefficacy tests conducted as per the protocol of World Health Organization and the LC(50) values calculated by the Probit analysis showed that 3(rd)-instar C. quinquefasciatus were more susceptible to the conidia of above fungi. Highest mortality was observed in the larvae of C. quinquefasciatus when exposed to T. ajelloi. The density of fungal conidia was greatest on the ventral brush, palmate hair and anal region of the mosquito larvae after exposing for 72 hours. The potentiality of these fungi for use in the control of C. quinquefasciatus is discussed which can be exploited as a suitable biocontrol agent in the tropics.

Phylogenetic congruence between subtropical trees and their associated fungi

NARCIS (Netherlands)

Liu, Xubing; Liang, Minxia; Etienne, Rampal S.; Gilbert, Gregory S; Yu, Shixiao

2016-01-01

Recent studies have detected phylogenetic signals in pathogen-host networks for both soil-borne and leaf-infecting fungi, suggesting that pathogenic fungi may track or coevolve with their preferred hosts. However, a phylogenetically concordant relationship between multiple hosts and multiple fungi

Advances in Genomics of Entomopathogenic Fungi.

Science.gov (United States)

Wang, J B; St Leger, R J; Wang, C

2016-01-01

Fungi are the commonest pathogens of insects and crucial regulators of insect populations. The rapid advance of genome technologies has revolutionized our understanding of entomopathogenic fungi with multiple Metarhizium spp. sequenced, as well as Beauveria bassiana, Cordyceps militaris, and Ophiocordyceps sinensis among others. Phylogenomic analysis suggests that the ancestors of many of these fungi were plant endophytes or pathogens, with entomopathogenicity being an acquired characteristic. These fungi now occupy a wide range of habitats and hosts, and their genomes have provided a wealth of information on the evolution of virulence-related characteristics, as well as the protein families and genomic structure associated with ecological and econutritional heterogeneity, genome evolution, and host range diversification. In particular, their evolutionary transition from plant pathogens or endophytes to insect pathogens provides a novel perspective on how new functional mechanisms important for host switching and virulence are acquired. Importantly, genomic resources have helped make entomopathogenic fungi ideal model systems for answering basic questions in parasitology, entomology, and speciation. At the same time, identifying the selective forces that act upon entomopathogen fitness traits could underpin both the development of new mycoinsecticides and further our understanding of the natural roles of these fungi in nature. These roles frequently include mutualistic relationships with plants. Genomics has also facilitated the rapid identification of genes encoding biologically useful molecules, with implications for the development of pharmaceuticals and the use of these fungi as bioreactors. Copyright © 2016 Elsevier Inc. All rights reserved.

Adult trees cause density-dependent mortality in conspecific seedlings by regulating the frequency of pathogenic soil fungi.

Science.gov (United States)

Liang, Minxia; Liu, Xubing; Gilbert, Gregory S; Zheng, Yi; Luo, Shan; Huang, Fengmin; Yu, Shixiao

2016-12-01

Negative density-dependent seedling mortality has been widely detected in tropical, subtropical and temperate forests, with soil pathogens as a major driver. Here we investigated how host density affects the composition of soil pathogen communities and consequently influences the strength of plant-soil feedbacks. In field censuses of six 1-ha permanent plots, we found that survival was much lower for newly germinated seedlings that were surrounded by more conspecific adults. The relative abundance of pathogenic fungi in soil increased with increasing conspecific tree density for five of nine tree species; more soil pathogens accumulated around roots where adult tree density was higher, and this greater pathogen frequency was associated with lower seedling survival. Our findings show how tree density influences populations of soil pathogens, which creates plant-soil feedbacks that contribute to community-level and population-level compensatory trends in seedling survival. © 2016 John Wiley & Sons Ltd/CNRS.

Diversity of Endophytic Fungi from Red Ginger (Zingiber officinale Rosc. Plant and Their Inhibitory Effect to Fusarium oxysporum Plant Pathogenic Fungi

Directory of Open Access Journals (Sweden)

SIHEGIKO KANAYA

2013-09-01

Full Text Available Indonesia has been known as a country with high medicinal plant diversity. One of the most common medicinal plant from Indonesia is red ginger (Zingiber officinale Rosc.. Nevertheless, limited studies of endophytic fungi associated with these medicinal plants are hitherto available. The objectives of this research were to study the diversity of endophytic fungi on red ginger and to analyze their potential as a source of antifungal agent. All parts of plant organs such as leaf, rhizome, root, and stem were subjected for isolation. Fungal identification was carried out by using a combination of morphological characteristic and molecular analysis of DNA sequence generated from ITS rDNA region. Thirty endophytic fungi were successfully isolated from leaf, rhizome, root, and stem of red ginger plant. Antagonistic activity was tested against Fusarium oxysporum, a pathogenic fungus on plants, using an antagonistic assay. Based on this approach, the fungi were assigned as Acremonium macroclavatum, Beltraniella sp., Cochliobolus geniculatus and its anamorphic stage Curvularia affinis, Fusarium solani, Glomerella cingulata, and its anamorphic stage Colletotrichum gloeosporoides, Lecanicillium kalimantanense, Myrothecium verrucaria, Neonectria punicea, Periconia macrospinosa, Rhizopycnis vagum, and Talaromyces assiutensis. R. vagum was found specifically on root whereas C. affinis, L. kalimantanense, and M. verrucaria were found on stem of red ginger plant. A. macroclavatum was found specifically in red ginger plant’s organ which located under the ground, whereas C. affinis was found from shoot or organ which located above the ground. The antagonistic activity of isolated endophytic fungi against F. oxysporum varied with the inhibition value range from 1.4 to 68.8%. C. affinis (JMbt7, F. solani (JMd14, and G. cingulata (JMr2 had significantly high antagonistic activity with the value above 65%; and R. vagum (JMa4 and C. geniculatus (JMbt9 had

Diversity of Endophytic Fungi from Red Ginger (Zingiber officinale Rosc. Plant and Their Inhibitory Effect to Fusarium oxysporum Plant Pathogenic Fungi

Directory of Open Access Journals (Sweden)

ROHANI CINTA BADIA GINTING

2013-09-01

Full Text Available Indonesia has been known as a country with high medicinal plant diversity. One of the most common medicinal plant from Indonesia is red ginger (Zingiber officinale Rosc.. Nevertheless, limited studies of endophytic fungi associated with these medicinal plants are hitherto available. The objectives of this research were to study the diversity of endophytic fungi on red ginger and to analyze their potential as a source of antifungal agent. All parts of plant organs such as leaf, rhizome, root, and stem were subjected for isolation. Fungal identification was carried out by using a combination of morphological characteristic and molecular analysis of DNA sequence generated from ITS rDNA region. Thirty endophytic fungi were successfully isolated from leaf, rhizome, root, and stem of red ginger plant. Antagonistic activity was tested against Fusarium oxysporum, a pathogenic fungus on plants, using an antagonistic assay. Based on this approach, the fungi were assigned as Acremonium macroclavatum, Beltraniella sp., Cochliobolus geniculatus and its anamorphic stage Curvularia affinis, Fusarium solani, Glomerella cingulata and its anamorphic stage Colletotrichum gloeosporoides, Lecanicillium kalimantanense, Myrothecium verrucaria, Neonectria punicea, Periconia macrospinosa, Rhizopycnis vagum, and Talaromyces assiutensis. R. vagum was found specifically on root whereas C. affinis, L. kalimantanense, and M. verrucaria were found on stem of red ginger plant. A. macroclavatum was found specifically in red ginger plant's organ which located under the ground, whereas C. affinis was found from shoot or organ which located above the ground. The antagonistic activity of isolated endophytic fungi against F. oxysporum varied with the inhibition value range from 1.4 to 68.8%. C. affinis (JMbt7, F. solani (JMd14, and G. cingulata (JMr2 had significantly high antagonistic activity with the value above 65%; and R. vagum (JMa4 and C. geniculatus (JMbt9 had significantly

Antifungal Activities of Extracts from Selected Lebanese Wild Plants against Plant Pathogenic Fungi

Directory of Open Access Journals (Sweden)

Y. Abou-Jawdah

2004-12-01

Full Text Available Extracts of nine plant species growing wild in Lebanon were tested for their efficacy against seven plant pathogenic fungi: Botrytis cinerea, Alternaria solani, Penicillium sp., Cladosporium sp., Fusarium oxysporum f. sp. melonis, Rhizoctonia solani and Sphaerotheca cucurbitae. Extracts of three of the plants, Origanum syriacum, Micromeria nervosa and Plumbago maritima, showed the highest levels of in vitro activity against spore germination and mycelial growth of the fungi tested. Inula viscosa showed high activity against spore germination but only moderate activity against mycelial growth. The other five plant species tested Calamintha origanifolia, Micromeria juliana, Ruta sp., Sideritis pullulans and Urginea maritima showed only moderate to low activity against these fungi. Preventive sprays with extracts of O. syriacum, M. nervosa, P. maritima and I. viscosa, applied at concentrations ranging between 4 and 8% to squash and cucumber seedlings, gave efficient protection against gray mold caused by B. cinerea and powdery mildew caused by S. cucurbitae. However, these extracts did not control green mold of citrus fruits caused by Penicillium sp. Thin layer chromatography revealed three inhibitory bands in extracts of O. syriacum, two in I. viscosa and only one in each of the other plants tested: M. nervosa, P. maritima, C. origanifolia and Ruta sp.

Fungi treated with small chemicals exhibit increased antimicrobial activity against facultative bacterial and yeast pathogens.

Science.gov (United States)

Zutz, Christoph; Bandian, Dragana; Neumayer, Bernhard; Speringer, Franz; Gorfer, Markus; Wagner, Martin; Strauss, Joseph; Rychli, Kathrin

2014-01-01

For decades, fungi have been the main source for the discovery of novel antimicrobial drugs. Recent sequencing efforts revealed a still high number of so far unknown "cryptic" secondary metabolites. The production of these metabolites is presumably epigenetically silenced under standard laboratory conditions. In this study, we investigated the effect of six small mass chemicals, of which some are known to act as epigenetic modulators, on the production of antimicrobial compounds in 54 spore forming fungi. The antimicrobial effect of fungal samples was tested against clinically facultative pathogens and multiresistant clinical isolates. In total, 30 samples of treated fungi belonging to six different genera reduced significantly growth of different test organisms compared to the untreated fungal sample (growth log reduction 0.3-4.3). For instance, the pellet of Penicillium restrictum grown in the presence of butyrate revealed significant higher antimicrobial activity against Staphylococcus (S.) aureus and multiresistant S. aureus strains and displayed no cytotoxicity against human cells, thus making it an ideal candidate for antimicrobial compound discovery. Our study shows that every presumable fungus, even well described fungi, has the potential to produce novel antimicrobial compounds and that our approach is capable of rapidly filling the pipeline for yet undiscovered antimicrobial substances.

A nitrogen response pathway regulates virulence in plant pathogenic fungi: role of TOR and the bZIP protein MeaB.

Science.gov (United States)

López-Berges, Manuel S; Rispail, Nicolas; Prados-Rosales, Rafael C; Di Pietro, Antonio

2010-12-01

Virulence in plant pathogenic fungi is controlled through a variety of cellular pathways in response to the host environment. Nitrogen limitation has been proposed to act as a key signal to trigger the in planta expression of virulence genes. Moreover, a conserved Pathogenicity mitogen activated protein kinase (MAPK) cascade is strictly required for plant infection in a wide range of pathogens. We investigated the relationship between nitrogen signaling and the Pathogenicity MAPK cascade in controlling infectious growth of the vascular wilt fungus Fusarium oxysporum. Several MAPK-activated virulence functions such as invasive growth, vegetative hyphal fusion and host adhesion were strongly repressed in the presence of the preferred nitrogen source ammonium. Repression of these functions by ammonium was abolished by L-Methionine sulfoximine (MSX) or rapamycin, two specific inhibitors of Gln synthetase and the protein kinase TOR (Target Of Rapamycin), respectively, and was dependent on the bZIP protein MeaB. Supplying tomato plants with ammonium rather than nitrate resulted in a significant delay of vascular wilt symptoms caused by the F. oxysporum wild type strain, but not by the ΔmeaB mutant. Ammonium also repressed invasive growth in two other pathogens, the rice blast fungus Magnaporthe oryzae and the wheat head blight pathogen Fusarium graminearum. Our results suggest the presence of a conserved nitrogen-responsive pathway that operates via TOR and MeaB to control infectious growth in plant pathogenic fungi.

Recent Updates on Treatment of Ocular Microbial Infections by Stem Cell Therapy: A Review

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Seoh Wei Teh

2018-02-01

Full Text Available Ocular microbial infection has emerged as a major public health crisis during the past two decades. A variety of causative agents can cause ocular microbial infections; which are characterized by persistent and destructive inflammation of the ocular tissue; progressive visual disturbance; and may result in loss of visual function in patients if early and effective treatments are not received. The conventional therapeutic approaches to treat vision impairment and blindness resulting from microbial infections involve antimicrobial therapy to eliminate the offending pathogens or in severe cases; by surgical methods and retinal prosthesis replacing of the infected area. In cases where there is concurrent inflammation, once infection is controlled, anti-inflammatory agents are indicated to reduce ocular damage from inflammation which ensues. Despite advances in medical research; progress in the control of ocular microbial infections remains slow. The varying level of ocular tissue recovery in individuals and the incomplete visual functional restoration indicate the chief limitations of current strategies. The development of a more extensive therapy is needed to help in healing to regain vision in patients. Stem cells are multipotent stromal cells that can give rise to a vast variety of cell types following proper differentiation protocol. Stem cell therapy shows promise in reducing inflammation and repairing tissue damage on the eye caused by microbial infections by its ability to modulate immune response and promote tissue regeneration. This article reviews a selected list of common infectious agents affecting the eye; which include fungi; viruses; parasites and bacteria with the aim of discussing the current antimicrobial treatments and the associated therapeutic challenges. We also provide recent updates of the advances in stem cells studies on sepsis therapy as a suggestion of optimum treatment regime for ocular microbial infections.

Recent Updates on Treatment of Ocular Microbial Infections by Stem Cell Therapy: A Review.

Science.gov (United States)

Teh, Seoh Wei; Mok, Pooi Ling; Abd Rashid, Munirah; Bastion, Mae-Lynn Catherine; Ibrahim, Normala; Higuchi, Akon; Murugan, Kadarkarai; Mariappan, Rajan; Subbiah, Suresh Kumar

2018-02-13

Ocular microbial infection has emerged as a major public health crisis during the past two decades. A variety of causative agents can cause ocular microbial infections; which are characterized by persistent and destructive inflammation of the ocular tissue; progressive visual disturbance; and may result in loss of visual function in patients if early and effective treatments are not received. The conventional therapeutic approaches to treat vision impairment and blindness resulting from microbial infections involve antimicrobial therapy to eliminate the offending pathogens or in severe cases; by surgical methods and retinal prosthesis replacing of the infected area. In cases where there is concurrent inflammation, once infection is controlled, anti-inflammatory agents are indicated to reduce ocular damage from inflammation which ensues. Despite advances in medical research; progress in the control of ocular microbial infections remains slow. The varying level of ocular tissue recovery in individuals and the incomplete visual functional restoration indicate the chief limitations of current strategies. The development of a more extensive therapy is needed to help in healing to regain vision in patients. Stem cells are multipotent stromal cells that can give rise to a vast variety of cell types following proper differentiation protocol. Stem cell therapy shows promise in reducing inflammation and repairing tissue damage on the eye caused by microbial infections by its ability to modulate immune response and promote tissue regeneration. This article reviews a selected list of common infectious agents affecting the eye; which include fungi; viruses; parasites and bacteria with the aim of discussing the current antimicrobial treatments and the associated therapeutic challenges. We also provide recent updates of the advances in stem cells studies on sepsis therapy as a suggestion of optimum treatment regime for ocular microbial infections.

Fungi that Infect Humans.

Science.gov (United States)

Köhler, Julia R; Hube, Bernhard; Puccia, Rosana; Casadevall, Arturo; Perfect, John R

2017-06-01

Fungi must meet four criteria to infect humans: growth at human body temperatures, circumvention or penetration of surface barriers, lysis and absorption of tissue, and resistance to immune defenses, including elevated body temperatures. Morphogenesis between small round, detachable cells and long, connected cells is the mechanism by which fungi solve problems of locomotion around or through host barriers. Secretion of lytic enzymes, and uptake systems for the released nutrients, are necessary if a fungus is to nutritionally utilize human tissue. Last, the potent human immune system evolved in the interaction with potential fungal pathogens, so few fungi meet all four conditions for a healthy human host. Paradoxically, the advances of modern medicine have made millions of people newly susceptible to fungal infections by disrupting immune defenses. This article explores how different members of four fungal phyla use different strategies to fulfill the four criteria to infect humans: the Entomophthorales, the Mucorales, the Ascomycota, and the Basidiomycota. Unique traits confer human pathogenic potential on various important members of these phyla: pathogenic Onygenales comprising thermal dimorphs such as Histoplasma and Coccidioides ; the Cryptococcus spp. that infect immunocompromised as well as healthy humans; and important pathogens of immunocompromised patients- Candida , Pneumocystis , and Aspergillus spp. Also discussed are agents of neglected tropical diseases important in global health such as mycetoma and paracoccidiomycosis and common pathogens rarely implicated in serious illness such as dermatophytes. Commensalism is considered, as well as parasitism, in shaping genomes and physiological systems of hosts and fungi during evolution.

Morphological characteristics and pathogenicity of fungi associated with Roselle (Hibiscus Sabdariffa) diseases in Penang, Malaysia.

Science.gov (United States)

Eslaminejad, Touba; Zakaria, Maziah

2011-11-01

Roselle, or Jamaica sorrel (Hibiscus sabdariffa) is a popular vegetable in many tropical regions, cultivated for its leaves, seeds, stems and calyces which, the dried calyces are used to prepare tea, syrup, jams and jellies and as beverages. The main objectives of this study were to identify and characterise fungal pathogens associated with Roselle diseases based on their morphological and cultural characteristics and to determine the pathogenicity of four fungi infecting Roselle seedlings, namely Phoma exigua, Fusarium nygamai, Fusarium tgcq and Rhizoctonia solani in Penang. A total of 200 fungal isolates were obtained from 90 samples of symptomatic Roselle tissues. The isolates were identified based on cultural and morphological characteristics, as well as their pathogenicity. The fungal pathogen most frequently isolated was P. exigua (present in 45% of the samples), followed by F. nygamai (25%), Rhizoctonia solani (19%) and F. camptoceras (11%). Pathogenicity tests showed that P. exigua, F. nygamai, F. camptoceras and R. solani were able to infect both wounded and unwounded seedlings with different degrees of severity as indicated by the Disease severity (DS). R. solani was the most pathogenic fungus affecting both wounded and unwounded Roselle seedlings, followed by P. exigua that was highly pathogenic on wounded seedlings. F. nygamai was less pathogenic while the least pathogenic fungus was F. camptoceras, infecting only the unwounded seedlings but, surprisingly, not the wounded plants. Copyright © 2011 Elsevier Ltd. All rights reserved.

Fungi

DEFF Research Database (Denmark)

Hajek, Ann E.; Meyling, Nicolai Vitt

2018-01-01

been the focus of most ecological research. Some taxa of invertebrate pathogenic fungi have evolved adaptations for utilizing living plants as substrates, and these lifestyles have recently received increased attention from researchers following the initial documentations of such plant associations...

Entomopathogenic fungi as biological controllers: New insights into their virulence and pathogenicity

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Shahid Ali Ahmad

2012-01-01

Full Text Available Entomopathogenic fungi vary considerably in their mode of action and virulence. Successful infection depends primarily on the adherence and penetration ability of a fungus to the host integuments. A variety of extracellular enzymes is produced during the degradation of insect integument. The attempts to control insects have changed over time from chemicals to natural control methods. This is why the development of natural methods of insect control or biopesticides, is preferred. By the use of fungal entomopathogens, insect pests can be controlled. There is no doubt that insects have been used for many years, but their effective use in the field remains elusive. However, their additional role in nature has also been discovered. Comparison of entomopathogens with conventional chemical pesticides depends on their efficiency and cost. In addition to efficiency, there are advantages in using microbial control agents, such as human safety and other non-target organisms; pesticide residues are minimized in food and biodiversity increased in managed ecosystems. In the present review the pathogenicity and virulence of entomopathogenic fungi and their role as biological control agents using biotechnology will be discussed.

Isolation and identification of local bacteria endophyte and screening of its antimicrobial property against pathogenic bacteria and fungi

Science.gov (United States)

Fikri, Ahmad Syairazie Ibrahim; Rahman, Irman Abdul; Nor, Norefrina Shafinaz Md; Hamzah, Ainon

2018-04-01

Endophytes are organisms, often fungi and bacteria that live in living plant cells. These organisms reside in the living tissues of the host plant in a variety of relationships, ranging from symbiotic to slightly pathogenic. The endophytes may produce a plethora of substances that have potential to be used in modern medicine, agriculture and industry. The aims of this study are to isolate, identify and screening antimicrobial activity of bacterial endophytes. The endophytes were isolated using nutrient agar, incubated at 37°C for 48 hours. Identification of the isolates were done based on morphological characteristics, biochemical tests and 16S rDNA molecular analysis. Disk diffusion method was used to screen for antimicrobial activity of metabolites from endophytes against pathogenic bacteria. Screening for antifungal activity of selected endophytes was done using dual culture method againts pathogenic fungi followed by Kirby-Bauer method. Results showed endophytes designated as B2c and B7b have positive antimicrobial activity. The metabolites from isolate B2c showed antimicrobial activity against pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Staphylococcus epidermis, while isolate B7b have positive activities againts MRSA, S. aureus and Pseudomonas aeruginosa. Isolates B2c displayed antifungal activity against Fusarium oxysporum, Fusarium solani, Phytophthora palmivora and Colletotrichum gloeosporioides. Identification using biochemical tests and 16S rDNA sequences identified isolate B2c as Pseudomonas resinovorans with 97% homology and isolate B7b as Bacillus subtilis with 98% homology.

Exploiting amoeboid and non-vertebrate animal model systems to study the virulence of human pathogenic fungi.

Science.gov (United States)

Mylonakis, Eleftherios; Casadevall, Arturo; Ausubel, Frederick M

2007-07-27

Experiments with insects, protozoa, nematodes, and slime molds have recently come to the forefront in the study of host-fungal interactions. Many of the virulence factors required for pathogenicity in mammals are also important for fungal survival during interactions with non-vertebrate hosts, suggesting that fungal virulence may have evolved, and been maintained, as a countermeasure to environmental predation by amoebae and nematodes and other small non-vertebrates that feed on microorganisms. Host innate immune responses are also broadly conserved across many phyla. The study of the interaction between invertebrate model hosts and pathogenic fungi therefore provides insights into the mechanisms underlying pathogen virulence and host immunity, and complements the use of mammalian models by enabling whole-animal high throughput infection assays. This review aims to assist researchers in identifying appropriate invertebrate systems for the study of particular aspects of fungal pathogenesis.

Patogenic fungi associated with blue lupine seeds

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Bogdan Nowicki

2013-12-01

Full Text Available Over 10% ofseeds harvested in 1991 and 1992 (50 samples, 400 seeds in each sample proved to be infested with various fungi. Fusarium spp. and Botrytis cinerea were the most common pathogens isolated. Fusarium avenaceum was the most common and highIy pathogenic species. Fusarium semitectum and F. tricinctum were highly pathogenic to lupin seedlings but they were the least common Fusarium isolated from seeds. Similarily, Sclerotinia sclerotiorum was isolated only from 0,2% seeds tested but this fungus was highly pathogenic to lupin seedlings. Some other fungi know as lupin pathogens (F. oxysporum, Stemphylium botryosum, Pleiochaeta setosa and Phomopsis leptostromiformis were also noted in tested seeds.

Isolation and Identification of Pathogenic Fungi from Thorns and Thistles in Isfahan and Adjacent Cities

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M Emami

2007-12-01

Full Text Available Introduction: The most important subcutaneous fungal infections in man are caused by injury due to contaminated thistles and thorns. From an epidemiological point of view , it is important to recognize the fungi as well as their frequency of them in various thistles and thorns Methods: The present research has been conducted on thorns and thistles of 16 regions including cities and villages of Isfahan province. 800 samples have been collected. Specimens were inoculated and incubated at 25◦C in S & SCC medium. In order to isolate and identify the fungi, cultures in specific media, intraperitoneal injections of mice and disc diffusion test have been applied. Results: Over one year of study, 1676 colonies of actinomycetes and fungi were recognized. The most common fungi were as follows: Alternaria (22/4%,Aspergillus(11/8% , Cladosporium (10/8%,Esteril mycellium(10/6% and Penicillium (9/7%. The prevalence was most in Shahreza city(10/2% , while the least was in Ardestan(3%. The most prevalent yeasts were Candida tropicalis (50% , Rodotrula rubra (12/5% , Candida kerusei(11/4%,Trichosporon candida (7/9% , Unknown yeasts (6/8%, Candida gillermondi (5/7%, Saccharomyces cervisia (3/4%, Geotricum candidum and Trichosporon glabrata (Candida glabrata each one (1/1%. The prevalence was most in Khansar city(19/2%. In this study, 4 species similar to Coccidioides immitis, Phialophora verrucosa (4 species and Exophiala jeanselmei (3 species were identified. Conclusion: In this study done for the first time in this area, pathogenic and opportunistic fungi were isolated. Furthermore, Exophiala jeanselmei and Nocardiopsis dassonvillei were isolated for the first time from thorns in the country.

Host pathogen relations: exploring animal models for fungal pathogens.

Science.gov (United States)

Harwood, Catherine G; Rao, Reeta P

2014-06-30

Pathogenic fungi cause superficial infections but pose a significant public health risk when infections spread to deeper tissues, such as the lung. Within the last three decades, fungi have been identified as the leading cause of nosocomial infections making them the focus of research. This review outlines the model systems such as the mouse, zebrafish larvae, flies, and nematodes, as well as ex vivo and in vitro systems available to study common fungal pathogens.

Impact of selected antagonistic fungi on Fusarium species – toxigenic cereal pathogens

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Delfina Popiel

2013-12-01

Full Text Available Fusarium-ear blight is a destructive disease in various cereal-growing regions and leads to significant yield and quality losses for farmers and to contamination of cereal grains with mycotoxins, mainly deoxynivalenol and derivatives, zearalenone and moniliformin. Fusarium pathogens grow well and produce significant inoculum on crop resiudues. Reduction of mycotoxins production and pathogen sporulation may be influenced by saprophytic fungi, exhibiting antagonistic effect. Dual culture bioassays were used to examine the impact of 92 isolates (belonging to 29 fungal species against three toxigenic species, i.e. Fusarium avenaceum (Corda Saccardo, F. culmorum (W.G.Smith Saccardo and F. graminearum Schwabe. Both F.culmorum and F. graminearum isolates produce trichothecene mycotoxins and mycohormone zearalenone and are considered to be the most important cereal pathogens worldwide. Infection with those pathogens leads to accumulation of mycotoxins: deoxynivalenol (DON and zearalenone (ZEA in grains. Fusarium avenaceum isolates are producers of moniliformin (MON and enniatins. Isolates of Trichoderma sp. were found to be the most effective ones to control the growth of examined Fusarium species. The response of Fusarium isolates to antagonistic activity of Trichoderma isolates varied and also the isolates of Trichoderma differed in their antagonistic activity against Fusarium isolates. The production of MON by two isolates of F. avenaceum in dual culture on rice was reduced by 95% to 100% by T. atroviride isolate AN 35. The same antagonist reduced the amount of moniliformin from 100 μg/g to 6.5 μg/g when inoculated to rice culture contaminated with MON, which suggests the possible decomposition of this mycotoxin.

Ocular TRUST: nationwide antimicrobial susceptibility patterns in ocular isolates.

Science.gov (United States)

Asbell, Penny A; Colby, Kathryn A; Deng, Sophie; McDonnell, Peter; Meisler, David M; Raizman, Michael B; Sheppard, John D; Sahm, Daniel F

2008-06-01

Ocular Tracking Resistance in U.S. Today (TRUST) annually evaluates in vitro antimicrobial susceptibility of Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae to ciprofloxacin, gatifloxacin, levofloxacin, moxifloxacin, penicillin, azithromycin, tobramycin, trimethoprim, and polymyxin B in national samples of ocular isolates. Laboratory investigation. Prospectively collected ocular isolates (197 S. aureus, 49 S. pneumoniae, and 32 H. influenzae) from 35 institutions and archived ocular isolates (760 S. pneumoniae and 356 H. influenzae) from 34 institutions were tested by an independent, central laboratory. Mean minimum inhibitory concentrations that would inhibit growth of 90% of the tested isolates (MIC(90)) were interpreted as susceptible, intermediate, or resistant according to standardized breakpoints for systemic treatment. S. aureus isolates were classified as methicillin susceptible (MSSA) or methicillin resistant (MRSA). MSSA or MRSA susceptibility patterns were virtually identical for the fluoroquinolones, that is, MSSA susceptibility was 79.9% to 81.1% and MRSA susceptibility was 15.2%. Trimethoprim was the only agent tested with high activity against MRSA. All S. pneumoniae isolates were susceptible to gatifloxacin, levofloxacin, and moxifloxacin; 89.8% were susceptible to ciprofloxacin. H. influenzae isolates were 100% susceptible to all tested agents but trimethoprim. Ocular TRUST 1 data were consistent with the eight-year longitudinal sample of archived ocular isolates. The fluoroquinolones were consistently active in MSSA, S. pneumoniae, and H. influenzae. After more than a decade of intensive ciprofloxacin and levofloxacin use as systemic therapy, 100% of ocular S. pneumoniae isolates were susceptible to gatifloxacin, levofloxacin, and moxifloxacin; nonsusceptibility to ciprofloxacin was less than 15%. High-level in vitro MRSA resistance suggests the need to consider alternative therapy to fluoroquinolones when MRSA is a

Exploiting amoeboid and non-vertebrate animal model systems to study the virulence of human pathogenic fungi.

Directory of Open Access Journals (Sweden)

Eleftherios Mylonakis

2007-07-01

Full Text Available Experiments with insects, protozoa, nematodes, and slime molds have recently come to the forefront in the study of host-fungal interactions. Many of the virulence factors required for pathogenicity in mammals are also important for fungal survival during interactions with non-vertebrate hosts, suggesting that fungal virulence may have evolved, and been maintained, as a countermeasure to environmental predation by amoebae and nematodes and other small non-vertebrates that feed on microorganisms. Host innate immune responses are also broadly conserved across many phyla. The study of the interaction between invertebrate model hosts and pathogenic fungi therefore provides insights into the mechanisms underlying pathogen virulence and host immunity, and complements the use of mammalian models by enabling whole-animal high throughput infection assays. This review aims to assist researchers in identifying appropriate invertebrate systems for the study of particular aspects of fungal pathogenesis.

Dermatophytes and other pathogenic fungi from hospital staff ...

African Journals Online (AJOL)

hospital staff apparel from protective gown, face- shields and hand gloves were tested for the presence of fungi. Examined samples were collected using the swab culture method. Results: Of a total of 110 swab samples of hospital staff apparel, 56 (51 %) showed fungi contamination including 31 (66 %) of 47 samples from ...

The sugarcane defense protein SUGARWIN2 causes cell death in Colletotrichum falcatum but not in non-pathogenic fungi.

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Flávia P Franco

Full Text Available Plants respond to pathogens and insect attacks by inducing and accumulating a large set of defense-related proteins. Two homologues of a barley wound-inducible protein (BARWIN have been characterized in sugarcane, SUGARWIN1 and SUGARWIN2 (sugarcane wound-inducible proteins. Induction of SUGARWINs occurs in response to Diatraea saccharalis damage but not to pathogen infection. In addition, the protein itself does not show any effect on insect development; instead, it has antimicrobial activities toward Fusarium verticillioides, an opportunistic fungus that usually occurs after D. saccharalis borer attacks on sugarcane. In this study, we sought to evaluate the specificity of SUGARWIN2 to better understand its mechanism of action against phytopathogens and the associations between fungi and insects that affect plants. We used Colletotrichum falcatum, a fungus that causes red rot disease in sugarcane fields infested by D. saccharalis, and Ceratocystis paradoxa, which causes pineapple disease in sugarcane. We also tested whether SUGARWIN2 is able to cause cell death in Aspergillus nidulans, a fungus that does not infect sugarcane, and in the model yeast Saccharomyces cerevisiae, which is used for bioethanol production. Recombinant SUGARWIN2 altered C. falcatum morphology by increasing vacuolization, points of fractures and a leak of intracellular material, leading to germling apoptosis. In C. paradoxa, SUGARWIN2 showed increased vacuolization in hyphae but did not kill the fungi. Neither the non-pathogenic fungus A. nidulans nor the yeast S. cerevisiae was affected by recombinant SUGARWIN2, suggesting that the protein is specific to sugarcane opportunistic fungal pathogens.

Phytopharmacology of the rice diseases. I. In vitro tests on application of the dust fungicides to the important pathogenic fungi

Energy Technology Data Exchange (ETDEWEB)

Hashioka, Y; Saito, T

1953-01-01

In this paper, the results of experiments on the repressing effect of selected fungicides on the growth of pathogenic fungi of rice are reported. Organic mercury compounds were tested and found to be more effective fungicides than copper. Their use in agriculture is recommended.

Host Pathogen Relations: Exploring Animal Models for Fungal Pathogens

Directory of Open Access Journals (Sweden)

Catherine G. Harwood

2014-06-01

Full Text Available Pathogenic fungi cause superficial infections but pose a significant public health risk when infections spread to deeper tissues, such as the lung. Within the last three decades, fungi have been identified as the leading cause of nosocomial infections making them the focus of research. This review outlines the model systems such as the mouse, zebrafish larvae, flies, and nematodes, as well as ex vivo and in vitro systems available to study common fungal pathogens.

Mycological assessment of sediments in Ligurian beaches in the Northwestern Mediterranean: pathogens and opportunistic pathogens.

Science.gov (United States)

Salvo, Vanessa-Sarah; Fabiano, Mauro

2007-05-01

Sediments of five Ligurian beaches in compliance with European Union bathing water regulations were studied based on the characteristics of the fungal assemblage during the tourism season. Among the 179 taxa of filamentous fungi isolated, 120 were opportunistic pathogens, such as Acremonium sp., and the genus Penicillium was also present as the pathogenic species P. citrinum. Furthermore, 5% of the total filamentous fungi belonged to the dermatophyte genus Microsporum, whose species can cause mycoses. Beach sediments showed elevated densities of opportunistic pathogens, of pathogenic filamentous fungi, and of yeasts during the tourism season. Although monitoring of beach sediments for microbiological contamination is not mandatory, and disease transmission from sediments has not yet been demonstrated, our study suggests that beach sediments may act as a reservoir of potential pathogens, including fungi. In addition, the mycoflora displayed high sensitivity to critical environmental situations in the beaches studied. Therefore, the fungal community can be a useful tool for assessing the quality of sandy beaches in terms of sanitary and environmental quality.

Analysis of Canadian and Irish forage, oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins

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Buckley Thomas

2007-04-01

Full Text Available Abstract Respiratory infections, recurrent airway obstruction (RAO and exercise induced pulmonary haemorrhage (EIPH are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites. This study set out to ascertain the degree of fungal and mycotoxin contamination in feed and fodder used in Irish racing yards over a one-year period. Weather conditions in forage producing areas were sampled by Met Eireann and the Canadian Meteorological Service. Fifty per cent of Irish hay, 37% of haylage and 13% of Canadian hay contained pathogenic fungi. Of the mycotoxins, T2 and zearalenone were most prominent. Twenty-one per cent of Irish hay and 16% of pelleted feed contained zearalenone. Forty per cent of oats and 54% of pelleted feed contained T2 toxins.

Analysis of Canadian and Irish forage, oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins.

Science.gov (United States)

Buckley, Thomas; Creighton, Alan; Fogarty, Ursula

2007-04-01

Respiratory infections, recurrent airway obstruction (RAO) and exercise induced pulmonary haemorrhage (EIPH) are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites.This study set out to ascertain the degree of fungal and mycotoxin contamination in feed and fodder used in Irish racing yards over a one-year period. Weather conditions in forage producing areas were sampled by Met Eireann and the Canadian Meteorological Service.Fifty per cent of Irish hay, 37% of haylage and 13% of Canadian hay contained pathogenic fungi. Of the mycotoxins, T2 and zearalenone were most prominent. Twenty-one per cent of Irish hay and 16% of pelleted feed contained zearalenone. Forty per cent of oats and 54% of pelleted feed contained T2 toxins.

Phylogenetic congruence between subtropical trees and their associated fungi.

Science.gov (United States)

Liu, Xubing; Liang, Minxia; Etienne, Rampal S; Gilbert, Gregory S; Yu, Shixiao

2016-12-01

Recent studies have detected phylogenetic signals in pathogen-host networks for both soil-borne and leaf-infecting fungi, suggesting that pathogenic fungi may track or coevolve with their preferred hosts. However, a phylogenetically concordant relationship between multiple hosts and multiple fungi in has rarely been investigated. Using next-generation high-throughput DNA sequencing techniques, we analyzed fungal taxa associated with diseased leaves, rotten seeds, and infected seedlings of subtropical trees. We compared the topologies of the phylogenetic trees of the soil and foliar fungi based on the internal transcribed spacer (ITS) region with the phylogeny of host tree species based on matK , rbcL , atpB, and 5.8S genes. We identified 37 foliar and 103 soil pathogenic fungi belonging to the Ascomycota and Basidiomycota phyla and detected significantly nonrandom host-fungus combinations, which clustered on both the fungus phylogeny and the host phylogeny. The explicit evidence of congruent phylogenies between tree hosts and their potential fungal pathogens suggests either diffuse coevolution among the plant-fungal interaction networks or that the distribution of fungal species tracked spatially associated hosts with phylogenetically conserved traits and habitat preferences. Phylogenetic conservatism in plant-fungal interactions within a local community promotes host and parasite specificity, which is integral to the important role of fungi in promoting species coexistence and maintaining biodiversity of forest communities.

High diversity of fungi in air particulate matter.

Science.gov (United States)

Fröhlich-Nowoisky, Janine; Pickersgill, Daniel A; Després, Viviane R; Pöschl, Ulrich

2009-08-04

Fungal spores can account for large proportions of air particulate matter, and they may potentially influence the hydrological cycle and climate as nuclei for water droplets and ice crystals in clouds, fog, and precipitation. Moreover, some fungi are major pathogens and allergens. The diversity of airborne fungi is, however, not well-known. By DNA analysis we found pronounced differences in the relative abundance and seasonal cycles of various groups of fungi in coarse and fine particulate matter, with more plant pathogens in the coarse fraction and more human pathogens and allergens in the respirable fine particle fraction (<3 microm). Moreover, the ratio of Basidiomycota to Ascomycota was found to be much higher than previously assumed, which might also apply to the biosphere.

Ubiquity of insect-derived nitrogen transfer to plants by endophytic insect-pathogenic fungi: an additional branch of the soil nitrogen cycle.

Science.gov (United States)

Behie, Scott W; Bidochka, Michael J

2014-03-01

The study of symbiotic nitrogen transfer in soil has largely focused on nitrogen-fixing bacteria. Vascular plants can lose a substantial amount of their nitrogen through insect herbivory. Previously, we showed that plants were able to reacquire nitrogen from insects through a partnership with the endophytic, insect-pathogenic fungus Metarhizium robertsii. That is, the endophytic capability and insect pathogenicity of M. robertsii are coupled so that the fungus acts as a conduit to provide insect-derived nitrogen to plant hosts. Here, we assess the ubiquity of this nitrogen transfer in five Metarhizium species representing those with broad (M. robertsii, M. brunneum, and M. guizhouense) and narrower insect host ranges (M. acridum and M. flavoviride), as well as the insect-pathogenic fungi Beauveria bassiana and Lecanicillium lecanii. Insects were injected with (15)N-labeled nitrogen, and we tracked the incorporation of (15)N into two dicots, haricot bean (Phaseolus vulgaris) and soybean (Glycine max), and two monocots, switchgrass (Panicum virgatum) and wheat (Triticum aestivum), in the presence of these fungi in soil microcosms. All Metarhizium species and B. bassiana but not L. lecanii showed the capacity to transfer nitrogen to plants, although to various degrees. Endophytic association by these fungi increased overall plant productivity. We also showed that in the field, where microbial competition is potentially high, M. robertsii was able to transfer insect-derived nitrogen to plants. Metarhizium spp. and B. bassiana have a worldwide distribution with high soil abundance and may play an important role in the ecological cycling of insect nitrogen back to plant communities.

Solar photocatalytic disinfection of agricultural pathogenic fungi (Curvularia sp.) in real urban wastewater.

Science.gov (United States)

Aguas, Yelitza; Hincapie, Margarita; Fernández-Ibáñez, Pilar; Polo-López, María Inmaculada

2017-12-31

The interest in developing alternative water disinfection methods that increase the access to irrigation water free of pathogens for agricultural purposes is increasing in the last decades. Advanced Oxidation Processes (AOPs) have been demonstrated to be very efficient for the abatement of several kind of pathogens in contaminated water. The purpose of the current study was to evaluate and compare the capability of several solar AOPs for the inactivation of resistant spores of agricultural fungi. Solar photoassisted H 2 O 2 , solar photo-Fenton at acid and near-neutral pH, and solar heterogeneous photocatalysis using TiO 2, with and without H 2 O 2 , have been studied for the inactivation of spores of Curvularia sp., a phytopathogenic fungi worldwide found in soils and crops. Different concentrations of reagents and catalysts were evaluated at bench scale (solar vessel reactors, 200mL) and at pilot plant scale (solar Compound Parabolic Collector-CPC reactor, 20L) under natural solar radiation using distilled water (DW) and real secondary effluents (SE) from a municipal wastewater treatment plant. Inactivation order of Curvularia sp. in distilled water was determined, i.e. TiO 2 /H 2 O 2 /sunlight (100/50mgL -1 )>H 2 O 2 /sunlight (40mgL -1 )>TiO 2 /sunlight (100mgL -1 )>photo-Fenton with 5/10mgL -1 of Fe 2+ /H 2 O 2 at pH3 and near-neutral pH. For the case of SE, at near neutral pH, the most efficient solar process was H 2 O 2 /Solar (60mgL -1 ); nevertheless, the best Curvularia sp. inactivation rate was obtained with photo-Fenton (10/20mgL -1 of Fe 2+ /H 2 O 2 ) requiring a previous water adicification to pH3, within 300 and 210min of solar treatment, respectively. These results show the efficiency of solar AOPs as a feasible option for the inactivation of resistant pathogens in water for crops irrigation, even in the presence of organic matter (average Dissolved Organic Carbon (DOC): 24mgL -1 ), and open a window for future wastewater reclamation and irrigation

Pathogenic Fungi Transmitted Through Cucumber Seeds and Safely Elimination by Application of Peppermint Extract and Oil

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Eman S.H. FARRAG

2012-08-01

Full Text Available Diseases induced by Fusarium, like damping-off and wilt on cucumber, are serious problems around the world. Samples of cucumber seeds were collected from commercial markets in Egypt and tested for seed-borne fungi. In order to detect the maximum number of internal and external seed-borne fungi, agar plate examination of disinfected and non-disinfected seeds were used. Two species of Fusarium were the most frequent and predominant fungi. Facultative parasites of the genera Alternaria, Rhizoctonia, Helminthosporium and Penicillium were also found. A total 33 isolates of Fusarium spp. were obtained using Komadas selective medium. Fusarium oxysporum and F. solani were highly frequent. Pathogenicity test indicated that, F. oxysporum isolate (Fem8 was the main causal organism of pre- and post-emergence damping off. Furthermore, it occurred in all seed parts tested. Some infected seeds germinate, but they were either rapidly overgrown by F. oxysporum or they developed into a diseased seedling. The water extract of garlic, peppermint and rheum completely inhibited the conidiospore germination and mycelial growth of F. oxysporum at tested conc. 3, 2 and 3%, respectively. Soaked seeds in 2% peppermint extract and evaporated seeds by vapor of peppermint oil caused a highly reduction in the infection and reduced transmission of the referred fungi from seeds to the growing seedlings. The vigor of cucumber seedlings raised from the treated seeds was better than that developed from untreated ones.

Pathogenic Fungi Transmitted Through Cucumber Seeds and Safely Elimination by Application of Peppermint Extract and Oil

Directory of Open Access Journals (Sweden)

Eman S.H. FARRAG

2012-08-01

Full Text Available Diseases induced by Fusarium, like damping-off and wilt on cucumber, are serious problems around the world. Samples of cucumber seeds were collected from commercial markets in Egypt and tested for seed-borne fungi. In order to detect the maximum number of internal and external seed-borne fungi, agar plate examination of disinfected and non-disinfected seeds were used. Two species of Fusarium were the most frequent and predominant fungi. Facultative parasites of the genera Alternaria, Rhizoctonia, Helminthosporium and Penicillium were also found. A total 33 isolates of Fusarium spp. were obtained using Komada�s selective medium. Fusarium oxysporum and F. solani were highly frequent. Pathogenicity test indicated that, F. oxysporum isolate (Fem8 was the main causal organism of pre- and post-emergence damping off. Furthermore, it occurred in all seed parts tested. Some infected seeds germinate, but they were either rapidly overgrown by F. oxysporum or they developed into a diseased seedling. The water extract of garlic, peppermint and rheum completely inhibited the conidiospore germination and mycelial growth of F. oxysporum at tested conc. 3, 2 and 3%, respectively. Soaked seeds in 2% peppermint extract and evaporated seeds by vapor of peppermint oil caused a highly reduction in the infection and reduced transmission of the referred fungi from seeds to the growing seedlings. The vigor of cucumber seedlings raised from the treated seeds was better than that developed from untreated ones.

Combinations of biocontrol agents for management of plant-parasitic nematodes and soilborne plant-pathogenic fungi.

Science.gov (United States)

Meyer, Susan L F; Roberts, Daniel P

2002-03-01

Numerous microbes are antagonistic to plant-parasitic nematodes and soilborne plant-pathogenic fungi, but few of these organisms are commercially available for management of these pathogens. Inconsistent performance of applied biocontrol agents has proven to be a primary obstacle to the development of successful commercial products. One of the strategies for overcoming inconsistent performance is to combine the disease-suppressive activity of two (or more) beneficial microbes in a biocontrol preparation. Such combinations have potential for more extensive colonization of the rhizosphere, more consistent expression of beneficial traits under a broad range of soil conditions, and antagonism to a larger number of plant pests or pathogens than strains applied individually. Conversely, microbes applied in combination also may have antagonistic interactions with each other. Increased, decreased, and unaltered suppression of the target pathogen or pest has been observed when biocontrol microbes have been applied in combination. Unfortunately, the ecological basis for increased or decreased suppression has not been determined in many cases and needs further consideration. The complexity of interactions involved in the application of multiple organisms for biological control has slowed progress toward development of successful formulations. However, this approach has potential for overcoming some of the efficacy problems that occur with application of individual biocontrol agents.

In situ hybridization for the detection of rust fungi in paraffin embedded plant tissue sections.

Science.gov (United States)

Ellison, Mitchell A; McMahon, Michael B; Bonde, Morris R; Palmer, Cristi L; Luster, Douglas G

2016-01-01

Rust fungi are obligate pathogens with multiple life stages often including different spore types and multiple plant hosts. While individual rust pathogens are often associated with specific plants, a wide range of plant species are infected with rust fungi. To study the interactions between these important pathogenic fungi and their host plants, one must be able to differentiate fungal tissue from plant tissue. This can be accomplished using the In situ hybridization (ISH) protocol described here. To validate reproducibility using the ISH protocol, samples of Chrysanthemum × morifolium infected with Puccinia horiana, Gladiolus × hortulanus infected with Uromyces transversalis and Glycine max infected with Phakopsora pachyrhizi were tested alongside uninfected leaf tissue samples. The results of these tests show that this technique clearly distinguishes between rust pathogens and their respective host plant tissues. This ISH protocol is applicable to rust fungi and potentially other plant pathogenic fungi as well. It has been shown here that this protocol can be applied to pathogens from different genera of rust fungi with no background staining of plant tissue. We encourage the use of this protocol for the study of plant pathogenic fungi in paraffin embedded sections of host plant tissue.

Antagonism of rice phylloplane fungi against Cercospora oryzae

Science.gov (United States)

Mardani, A.; Hadiwiyono

2018-03-01

Narrow brown leaf spot (NBLS) caused by Cercospora oryzae Miyake is one of the important obstacle in rice cultivation that can decrease the productivity up to 40%. It has been known well that some phylloplane fungi are antagonistic to some leaf diseases. Phylloplane fungi of rice however haven’t been studied much and poorly understood as biological control agent of rice pathogen such C. oryzae. The research aimed to study the antagonism of some phylloplane fungi of rice against C. oryzae. At least 14 isolates of phylloplane fungi were collected which consisted of six pathogenic and eight nonpathogenic variants. All of nonpathogenic isolates were antagonistic against C. oryzae both in vitro and only one isolate could not inhibit the infection of the pathogen in vivo. Some isolates were identified as Aspergillus, Mucor, Penicillium, Fusarium, and Trichoderma. The isolate of Mucor and Fusarium could inhibit the highest growth of pathogen on potato dextrose medium that were at 36.0% and 35.5% respectively. Whereas on artificial inoculation on rice, some isolates such Penicillium and Fusarium could inhibit most effectively and were significantly different to Mencozeb application with dosage 5g L-1.

Nests of Marsh harrier (Circus aeruginosus L. as refuges of potentially phytopathogenic and zoopathogenic fungi

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Teresa Kornillowicz-Kowalska

2018-01-01

Full Text Available Birds’ nests may be refuges for various species of fungi including that which are potentially phytopathogenic and zoopathogenic. Among the 2449 isolates of fungi obtained from nests of Marsh harriers 96.8% belonged to filamentous fungi. In total, 37 genera were identified from 63 fungi species. Within the mycobiotas of the examined nests populations of fungi which are potentially pathogenic for humans, homoiothermous animals and plants dominated. Among 63 species, 46 (72% were potentially pathogenic fungi of which 18 species were potentially phytopathogenic and 32 species were pathogenic for homoiothermous animals. Inter alia species of fungi were found in the Marsh harriers nests: Aspergillus fumigatus, Aspergillus flavus, Scopulariopsis brevicaulis, Chrysosporium keratinophilum and Fusarium poae, Fusarium sporotrichioides. In terms of numbers, dominant in Marsh harrier nests were fungi pathogenic to birds, other homoiothermous animals and humans. On that basis it was concluded that Marsh harrier nests are both a source of fungal infections for that species and one of the links in the epidemiological cycle of opportunistic fungi for humans.

Nests of Marsh harrier (Circus aeruginosus L.) as refuges of potentially phytopathogenic and zoopathogenic fungi.

Science.gov (United States)

Kornillowicz-Kowalska, Teresa; Kitowski, Ignacy

2018-01-01

Birds' nests may be refuges for various species of fungi including that which are potentially phytopathogenic and zoopathogenic. Among the 2449 isolates of fungi obtained from nests of Marsh harriers 96.8% belonged to filamentous fungi. In total, 37 genera were identified from 63 fungi species. Within the mycobiotas of the examined nests populations of fungi which are potentially pathogenic for humans, homoiothermous animals and plants dominated. Among 63 species, 46 (72%) were potentially pathogenic fungi of which 18 species were potentially phytopathogenic and 32 species were pathogenic for homoiothermous animals. Inter alia species of fungi were found in the Marsh harriers nests: Aspergillus fumigatus , Aspergillus flavus , Scopulariopsis brevicaulis , Chrysosporium keratinophilum and Fusarium poae , Fusarium sporotrichioides . In terms of numbers, dominant in Marsh harrier nests were fungi pathogenic to birds, other homoiothermous animals and humans. On that basis it was concluded that Marsh harrier nests are both a source of fungal infections for that species and one of the links in the epidemiological cycle of opportunistic fungi for humans.

Molecular and phenotypic characterization of anamorphic fungi

OpenAIRE

Madrid Lorca, Hugo

2011-01-01

Anamorphic fungi (those reproducing asexually) are a big part of kingdom Fungi. Most of them occur as saprobes in nature, but numerous species are pathogenic to plants and animals including man. With the aim of contributing to the knowledge of the diversity and distribution of anamorphic fungi, we performed a phenotypic and molecular characterization of environmental and clinical isolates of these fungi. Based on a polyphasic taxonomy approach which included morphology, physiology and DNA seq...

Application of the EPR technique to examine free radical qualities reducing infection of spring wheat grain with pathogenic fungi by He-Ne laser irradiation

International Nuclear Information System (INIS)

Gagoś, M.; Koper, R.; Sujak, A.; Misiak, L.E.; Kowalczuk, E.

2000-01-01

Samples of spring wheat grain, Jasna cv., infected with pathogenic fungi (Aspergillus niger, Penicillium sp., Fusarium, Mucor) were examined using an EPR technique. Considering the quantity of generated free radicals the fungi belonged to most toxine generating. Their toxicity was connected with the number of free radicals generated in examined grain. Grain was irradiated with He-Ne laser at known wavelength, power density and time of exposure what gave the mycostatic effect appearing in decrease of free radicals in grain samples. However, this process was not stable as the increase of free radicals was observed again with the regrowth of fungi after some days

Fight Fungi with Fungi: Antifungal Properties of the Amphibian Mycobiome

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Patrick J. Kearns

2017-12-01

Full Text Available Emerging infectious diseases caused by fungal taxa are increasing and are placing a substantial burden on economies and ecosystems worldwide. Of the emerging fungal diseases, chytridomycosis caused by the fungus Batrachochytrium dendrobatidis (hereafter Bd is linked to global amphibian declines. Amphibians have innate immunity, as well as additional resistance through cutaneous microbial communities. Despite the targeting of bacteria as potential probiotics, the role of fungi in the protection against Bd infection in unknown. We used a four-part approach, including high-throughput sequencing of bacterial and fungal communities, cultivation of fungi, Bd challenge assays, and experimental additions of probiotic to Midwife Toads (Altyes obstetricans, to examine the overlapping roles of bacterial and fungal microbiota in pathogen defense in captive bred poison arrow frogs (Dendrobates sp.. Our results revealed that cutaneous fungal taxa differed from environmental microbiota across three species and a subspecies of Dendrobates spp. frogs. Cultivation of host-associated and environmental fungi realved numerous taxa with the ability to inhibit or facilitate the growth of Bd. The abundance of cutaneous fungi contributed more to Bd defense (~45% of the fungal community, than did bacteria (~10% and frog species harbored distinct inhibitory communities that were distinct from the environment. Further, we demonstrated that a fungal probiotic therapy did not induce an endocrine-immune reaction, in contrast to bacterial probiotics that stressed amphibian hosts and suppressed antimicrobial peptide responses, limiting their long-term colonization potential. Our results suggest that probiotic strategies against amphibian fungal pathogens should, in addition to bacterial probiotics, focus on host-associated and environmental fungi such as Penicillium and members of the families Chaetomiaceae and Lasiosphaeriaceae.

Ocular manifestations of injection drug use.

Science.gov (United States)

Kim, Rubin W; Juzych, Mark S; Eliott, Dean

2002-09-01

Injection drug use can result in a variety of severe ocular conditions. Hematogenous dissemination of various fungi and bacteria may produce endophthalmitis with resultant severe visual loss. Retinal arterial occlusive disease may result from talc and other particulate emboli. Most commonly, life-threatening systemic diseases such as endocarditis and HIV infection secondarily affect the eye. Because many of these conditions may result in blindness if untreated, accurate diagnosis and prompt initiation of therapy are essential.

Antifungal Activity of Tamarix aphylla (L. Karst. Stem-bark Extract Against Some Pathogenic Fungi

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Sadaf bibi bibi

2015-03-01

Full Text Available The largest identified, Tamarix aphylla (L. Karst. belonging to family Tamaricaceae is traditionally an important plant used to cure various ailments. Three concentrations of crude ethanolic extracts 2000 ppm, 1000 ppm and 500 ppm were tested against six pathogenic fungi: Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Fusarium oxysporum, Penicillium notatum and Saccharomyces cerevisiae using five different solvents: acetone, chloroform, distilled water (DW, ethanol and methanol. Percent inhibition in growth of fungi was found to be dose dependent. The standard antifungal synthetic drug, Terbinafine, was used in different concentrations mixed with distilled water against different test fungi. Terbinafine completely controlled the growth of A. flavus, A. fumigatus, A. niger, F. oxysporum, P. notatum and S. cerevisiae with the concentrations of 65±0.58, 72±1.00, 70±1.15, 59±1.00, 60±0.58 and 80±0.58 (µg/ml of PDA medium, respectively. Chloroform was considered to be the most effective solvent preventing 97.68±0.58% growth of F. oxysporum, 9.37±0.33% in A. niger, 92.68±3.33% in S. cerevisiae, 91.46±2.08% in A. fumigatus, 88.48±0.88% in A. flavus and 87.95±1.15% in P. notatum. Statistically, the results were compared with negative control and most of the results were found to be highly significant (p≤0.000. Overall, our results suggest that T. aphylla stem-bark extract illustrated maximum percent inhibition with chloroform followed by ethanol, acetone, methanol and distilled water.

Study of drinking water fungi and its pathogenic effects on human beings from district Bhimber, Azad Kashmir, Pakistan

International Nuclear Information System (INIS)

Hussain, T.; Ishtiaq, M.; Hussain, A.; Sultana, K.

2011-01-01

Pathogenic fungi of drinking water have potentially prevailing effects on human beings. Myco floral study of drinking water of district Bhimber, Azad Kashmir was conducted through systematic sampling and temporally during the year 2009. Drinking water samples were collected from selected spots and fungal spores were grown on two different culture media viz: potato dextrose agar (PDA) and nutrient agar (NA) and identified by employing Direct Plate method (DPM) and Baiting Technique (BT). A total of 4 resources of drinking water of the area were analyzed i.e., well, spring, hand pump and tap water (water supply system). Sixteen different fungal species were frequently prevailing in the analyzed samples and among these five species were predominantly found human pathogenic. The density of identified fungal species in well's water samples (WWS) was 11 spp. spring's water samples (SWS) 6 spp. hand pump water samples (HWS) 8 spp. and tap water samples (TWS) 7 spp. This differential incidence in the samples might be due to variation in geography, edaphalogy, altitude, temperature, in fungal growth substrate variance and analytical difference of sampling and analysis methods. The prevalence values of mycolfora in different samples were variable with WWS Mucor fragilis (18a - LSD), SWS Brevilegnia sp. (20a - LSD), HWS Aspergillus flavus (14a- LSD) and TWS Alternaria alternata (12a - LSD). It was noted that WWS more frequently depicted mycoflora because land/well provides best environment and nourishment for growth and reproduction of fungi. The economic importance and pathogenic toxicity of various species is also measured and documented in the article. (author)

Estudo laboratorial das micoses oculares e fatores associados às ceratites Laboratory study of the mycotic infectious eye diseases and factors associated with keratitis

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Ana Luisa Höfling-Lima

2005-02-01

Full Text Available OBJETIVO: Analisar a freqüência e a etiologia das doenças oculares micóticas diagnosticadas por cultura no Laboratório de Doenças Externas Oculares da Universidade Federal de São Paulo (LOFT-UNIFESP, São Paulo, SP, Brasil e os fatores associados às ceratites fúngicas. MÉTODOS: Estudo retrospectivo de 14.391 solicitações de exames laboratoriais de doenças infecciosas oculares no período compreendido entre 1975 e maio de 2003. Nas comprovações por cultura de micoses oculares foram observados o tipo morfológico do fungo isolado, o sexo e a idade dos pacientes, o local de acometimento da infecção ocular, os anos de identificação e os fatores associados nos casos de ceratite fúngica, conforme o agente etiológico identificado. Considerou-se significante pPURPOSE: To analyze the frequency and the etiology of mycotic infectious eye diseases diagnosed by culture at the Ocular Diseases Laboratory of the Federal University of São Paulo (LOFT-UNIFESP, São Paulo, SP, Brazil, and the factors associated with fungal keratitis. METHODS: We retrospectively analyzed the 14,391 laboratory requests regarding infectious eye diseases between 1975 and May 2003. For the fungal culture proven examinations we observed the morphologic type of the isolated fungus, the gender and age of the patient, the site of ocular involvement, the year of identification, and the factors associated with keratitis cases, according to the identified etiologic agent. Results were considered significant if p<0.05. RESULTS: We verified 296 (2.05% ocular mycosis cases with 265 keratitis (89.5%, 27 intraocular infections (9.1%, and 4 infections at other sites (1.3%. Filamentous fungi were isolated in 233 cases (78.7% 74.7% being male (n=174 and 25.3% female (n=59. Yeasts were isolated in 63 cases (21.3% 49.2% being male (n=31 and 50.8% female (n=32. Ages varied between 2 and 99 years in the filamentous fungi group and between 14 and 88 years in the yeast group. The most

β-1,3-1,4-glucanase gene from Bacillus velezensis ZJ20 exerts antifungal effect on plant pathogenic fungi.

Science.gov (United States)

Xu, Ting; Zhu, Tianhui; Li, Shujiang

2016-02-01

Bacillus velezensis is a known antifungal bacteria. To understand the role of β-1, 3-1, 4-glucanase played on B. velezensis about the mechanism which exerts effect on fungi, we isolated and cloned the β-1, 3-1, 4-glucanase gene (Bglu1) from B. velezensis ZJ20. The Bglu1 open reading frame was 732 bp that encoded a protein with 243 amino acids and a calculated molecular weight of 27.3 kDa. The same gene without the signal peptide, termed Bglu2, was also cloned and expressed in E. coli BL21. Among the two variants, only Bglu2 protein was expressed. Purified Bglu2 could be eluted with imidazole solution at concentrations ranging from 100 to 500 mM although the highest expression was observed at 150 and 200 mM and the purest was at 500 mM. In addition, activity of the crude enzyme was 1527 U ml(-1) and the highest activity of the purified enzyme was 1706 U ml(-1). The purified β-1, 3-1, 4-glucanase had activity on a wide range of pH and temperatures and displayed optimal activity at pH 5.0 and 35 °C. More importantly, the mycelial morphology of three pathogenic fungi was destroyed by the purified β-1, 3-1, 4-glucanase. In conclusion, β-1, 3-1, 4-glucanase from B. velezensis ZJ20 can be highly expressed in E. coli BL21 and the recombinant protein is pathogenic to fungi.

Sexual Reproduction of Human Fungal Pathogens

Science.gov (United States)

Heitman, Joseph; Carter, Dee A.; Dyer, Paul S.; Soll, David R.

2014-01-01

We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms. PMID:25085958

Current and future molecular diagnostics for ocular infectious diseases.

Science.gov (United States)

Doan, Thuy; Pinsky, Benjamin A

2016-11-01

Confirmation of ocular infections can pose great challenges to the clinician. A fundamental limitation is the small amounts of specimen that can be obtained from the eye. Molecular diagnostics can circumvent this limitation and have been shown to be more sensitive than conventional culture. The purpose of this review is to describe new molecular methods and to discuss the applications of next-generation sequencing-based approaches in the diagnosis of ocular infections. Efforts have focused on improving the sensitivity of pathogen detection using molecular methods. This review describes a new molecular target for Toxoplasma gondii-directed polymerase chain reaction assays. Molecular diagnostics for Chlamydia trachomatis and Acanthamoeba species are also discussed. Finally, we describe a hypothesis-free approach, metagenomic deep sequencing, which can detect DNA and RNA pathogens from a single specimen in one test. In some cases, this method can provide the geographic location and timing of the infection. Pathogen-directed PCRs have been powerful tools in the diagnosis of ocular infections for over 20 years. The use of next-generation sequencing-based approaches, when available, will further improve sensitivity of detection with the potential to improve patient care.

Evolution of entomopathogenicity in fungi.

Science.gov (United States)

Humber, Richard A

2008-07-01

The recent completions of publications presenting the results of a comprehensive study on the fungal phylogeny and a new classification reflecting that phylogeny form a new basis to examine questions about the origins and evolutionary implications of such major habits among fungi as the use of living arthropods or other invertebrates as the main source of nutrients. Because entomopathogenicity appears to have arisen or, indeed, have lost multiple times in many independent lines of fungal evolution, some of the factors that might either define or enable entomopathogenicity are examined. The constant proximity of populations of potential new hosts seem to have been a factor encouraging the acquisition or loss of entomopathogenicity by a very diverse range of fungi, particularly when involving gregarious and immobile host populations of scales, aphids, and cicadas (all in Hemiptera). An underlying theme within the vast complex of pathogenic and parasitic ascomycetes in the Clavicipitaceae (Hypocreales) affecting plants and insects seems to be for interkingdom host-jumping by these fungi from plants to arthropods and then back to the plant or on to fungal hosts. Some genera of Entomophthorales suggest that the associations between fungal pathogens and their insect hosts appear to be shifting away from pathogenicity and towards nonlethal parasitism.

Genetically Engineering Entomopathogenic Fungi.

Science.gov (United States)

Zhao, H; Lovett, B; Fang, W

2016-01-01

Entomopathogenic fungi have been developed as environmentally friendly alternatives to chemical insecticides in biocontrol programs for agricultural pests and vectors of disease. However, mycoinsecticides currently have a small market share due to low virulence and inconsistencies in their performance. Genetic engineering has made it possible to significantly improve the virulence of fungi and their tolerance to adverse conditions. Virulence enhancement has been achieved by engineering fungi to express insect proteins and insecticidal proteins/peptides from insect predators and other insect pathogens, or by overexpressing the pathogen's own genes. Importantly, protein engineering can be used to mix and match functional domains from diverse genes sourced from entomopathogenic fungi and other organisms, producing insecticidal proteins with novel characteristics. Fungal tolerance to abiotic stresses, especially UV radiation, has been greatly improved by introducing into entomopathogens a photoreactivation system from an archaean and pigment synthesis pathways from nonentomopathogenic fungi. Conversely, gene knockout strategies have produced strains with reduced ecological fitness as recipients for genetic engineering to improve virulence; the resulting strains are hypervirulent, but will not persist in the environment. Coupled with their natural insect specificity, safety concerns can also be mitigated by using safe effector proteins with selection marker genes removed after transformation. With the increasing public concern over the continued use of synthetic chemical insecticides and growing public acceptance of genetically modified organisms, new types of biological insecticides produced by genetic engineering offer a range of environmentally friendly options for cost-effective control of insect pests. Copyright © 2016 Elsevier Inc. All rights reserved.

Biochemical changes induced by five pathogenic fungi on seeds of ...

African Journals Online (AJOL)

Different biochemical analysis were carried out to determine the changes induced by some fungi inoculated on Hibiscus sabdariffa linn seed for 14days. The inoculated fungi are Aspergillus niger Van Tieghem, Aspergillus flavus Link Ex fr, Fusarium oxysporum Schlecht, Penicillium chrysogenum Thom and Penicillium ...

Oomycetes and fungi: similar weaponry to attack plants

NARCIS (Netherlands)

Latijnhouwers, M.; Wit, de P.J.G.M.; Govers, F.

2003-01-01

Fungi and Oomycetes are the two most important groups of eukaryotic plant pathogens. Fungi form a separate kingdom and are evolutionarily related to animals. Oomycetes are classified in the kingdom Protoctista and are related to heterokont, biflagellate, golden-brown algae. Fundamental differences

Genomic Encyclopedia of Fungi

Energy Technology Data Exchange (ETDEWEB)

Grigoriev, Igor

2012-08-10

Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 150 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.

Wild Honey Inhibits Growth od Some Phytopathogenic Fungi in vitro

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K.I. Al-Mughrabi

2003-12-01

Full Text Available Wild honey was diluted to 1000 ppm with sterile distilled water and tested in vitro for inhibition of the plant pathogenic fungi Fusarium oxysporum, Rhizoctonia solani, Alternaria solani, Stemphylium solani, Colletotrichum sp., and Phytophthora infestans. Wild honey was effective against all these fungi, particularly A. solani and P. infestans, the causal agents of early and late blight diseases respectively; also against R. solani and F. oxysporum, and to a less extent against S. solani and Colletotrichum sp. This is the first report on the inhibiting effect of wild honey against plant pathogenic fungi.

Functional analysis of the conserved transcriptional regulator CfWor1 in Cladosporium fulvum reveals diverse roles in the virulence of plant pathogenic fungi

NARCIS (Netherlands)

Ökmen, B.; Collemare, J.; Griffiths, S.A.; Burgt, van der A.; Cox, R.; Wit, de P.J.G.M.

2014-01-01

Fungal Wor1-like proteins are conserved transcriptional regulators that are reported to regulate the virulence of several plant pathogenic fungi by affecting the expression of virulence genes. Here, we report the functional analysis of CfWor1, the homologue of Wor1 in Cladosporium fulvum. ¿cfwor1

Thermophilic Fungi to Dominate Aflatoxigenic/Mycotoxigenic Fungi on Food under Global Warming.

Science.gov (United States)

Paterson, Robert Russell M; Lima, Nelson

2017-02-17

Certain filamentous fungi produce mycotoxins that contaminate food. Mycotoxin contamination of crops is highly influenced by environmental conditions and is already affected by global warming, where there is a succession of mycotoxigenic fungi towards those that have higher optimal growth temperatures. Aflatoxigenic fungi are at the highest limit of temperature although predicted increases in temperature are beyond that constraint. The present paper discusses what will succeed these fungi and represents the first such consideration. Aflatoxins are the most important mycotoxins and are common in tropical produce, much of which is exported to temperate regions. Hot countries may produce safer food under climate change because aflatoxigenic fungi will be inhibited. The same situation will occur in previously temperate regions where these fungi have recently appeared, although decades later. Existing thermotolerant and thermophilic fungi (TTF) will dominate, in contrast to the conventional mycotoxigenic fungi adapting or mutating, as it will be quicker. TTF produce a range of secondary metabolites, or potential mycotoxins and patulin which may become a new threat. In addition, Aspergillus fumigatus will appear more frequently, a serious human pathogen, because it is (a) thermotolerant and (b) present on crops: hence this is an even greater problem. An incubation temperature of 41 °C needs employing forthwith to detect TTF. Finally, TTF in crops requires study because of the potential for diseases in humans and animals under climate change.

Ocular Manifestations of Mosquito-Transmitted Diseases.

Science.gov (United States)

Karesh, James W; Mazzoli, Robert A; Heintz, Shannon K

2018-03-01

Of the 3,548 known mosquito species, about 100 transmit human diseases. Mosquitoes are distributed globally throughout tropical and temperate regions where standing water sources are available for egg laying and the maturation of larva. Female mosquitoes require blood meals for egg production. This is the main pathway for disease transmission. Mosquitoes carry several pathogenic organisms responsible for significant ocular pathology and vision loss including West Nile, Rift Valley, chikungunya, dengue viruses, various encephalitis viruses, malarial parasites, Francisella tularensis, microfilarial parasites, including Dirofilaria, Wuchereria, and Brugia spp., and human botfly larvae. Health care providers may not be familiar with many of these mosquito-transmitted diseases or their associated ocular findings delaying diagnosis, treatment, and recovery of visual function. This article aims to provide an overview of the ocular manifestations associated with mosquito-transmitted diseases.

The microscopic pathogenic fungi of the Łęczna-Włodawa Lake District. I. The occurrence of pathogenic fungi in plant communities and theirs phenology

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Wiesław Mułenko

2014-08-01

Full Text Available The paper presents the results of the studies on tbe occurrence and phenology of puthogenic fungi in plant communities of the Łęczna-Włodawa Lake District in 1981-1984. The taxonomic list of collected fungi species will be published in another paper.

Development of oligonucleotide microarrays for simultaneous multi-species identification of Phellinus tree-pathogenic fungi.

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Tzean, Yuh; Shu, Po-Yao; Liou, Ruey-Fen; Tzean, Shean-Shong

2016-03-01

Polyporoid Phellinus fungi are ubiquitously present in the environment and play an important role in shaping forest ecology. Several species of Phellinus are notorious pathogens that can affect a broad variety of tree species in forest, plantation, orchard and urban habitats; however, current detection methods are overly complex and lack the sensitivity required to identify these pathogens at the species level in a timely fashion for effective infestation control. Here, we describe eight oligonucleotide microarray platforms for the simultaneous and specific detection of 17 important Phellinus species, using probes generated from the internal transcribed spacer regions unique to each species. The sensitivity, robustness and efficiency of this Phellinus microarray system was subsequently confirmed against template DNA from two key Phellinus species, as well as field samples collected from tree roots, trunks and surrounding soil. This system can provide early, specific and convenient detection of Phellinus species for forestry, arboriculture and quarantine inspection, and could potentially help to mitigate the environmental and economic impact of Phellinus-related diseases. © 2015 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Investigations on the effects of triazole group fungicides on some important antagonistic fungi and non-pathogen Fusarium oxysporum (Schlecht) in vitro.

OpenAIRE

Demirci, A.; Katırcıoğlu, Z.; Demirci, F.

2008-01-01

The effects of eight triazole fungicides (cyproconazole, diniconazole, flusilazole hexaconazole, myclobutanil, penconazole, tebuconazole and triticinazole) on some important antagonistic fungi [Trichoderma harzianum (Rifai), T. viride (Pers. ex Gray), T. pseudokoningii (Rifai), T. hamatum (Bonard), Gliociadium viride (Matrouchot), Aspergillus niger (Tieghem), Penicillium verrııcosum (Dierckx)] and non-pathogen Fusarium oxysporum (Schlecht) were investigated on PDA in vitro. EC5 0 values ...

Biology of flower-infecting fungi.

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Ngugi, Henry K; Scherm, Harald

2006-01-01

The ability to infect host flowers offers important ecological benefits to plant-parasitic fungi; not surprisingly, therefore, numerous fungal species from a wide range of taxonomic groups have adopted a life style that involves flower infection. Although flower-infecting fungi are very diverse, they can be classified readily into three major groups: opportunistic, unspecialized pathogens causing necrotic symptoms such as blossom blights (group 1), and specialist flower pathogens which infect inflorescences either through the gynoecium (group 2) or systemically through the apical meristem (group 3). This three-tier system is supported by life history attributes such as host range, mode of spore transmission, degree of host sterilization as a result of infection, and whether or not the fungus undergoes an obligate sexual cycle, produces resting spores in affected inflorescences, and is r- or K-selected. Across the three groups, the flower as an infection court poses important challenges for disease management. Ecologically and evolutionarily, terms and concepts borrowed from the study of venereal (sexually transmitted) diseases of animals do not adequately capture the range of strategies employed by fungi that infect flowers.

Asymmetric total synthesis of 6-Tuliposide B and its biological activities against tulip pathogenic fungi.

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Shigetomi, Kengo; Omoto, Shoko; Kato, Yasuo; Ubukata, Makoto

2011-01-01

The structure-activity relationship was investigated to evaluate the antifungal activities of tuliposides and tulipalins against tulip pathogenic fungi. 6-Tuliposide B was effectively synthesized via the asymmetric Baylis-Hillman reaction. Tuliposides and tulipalins showed antifungal activities against most of the strains tested at high concentrations (2.5 mM), while Botrytis tulipae was resistant to tuliposides. Tulipalin formation was involved in the antifungal activity, tulipalin A showed higher inhibitory activity than 6-tuliposide B and tulipalin B. Both the tuliposides and tulipalins showed pigment-inducing activity against Gibberella zeae and inhibitory activity against Fusarium oxysporum f. sp tulipae. These activities were induced at a much lower concentration (0.05 mM) than the antifungal MIC values.

Susceptibility of different parsley cultivars to infestation by pathogenic fungi

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Jacek Nawrocki

2012-12-01

Full Text Available The experiments were carried out in the years 2002 and 2003 on parsley seeds of 6 cultivars: Alba, Berlińska, Cukrowa, Kinga, Lenka, and Vistula. Mycological analysis of parsley seeds showed that the most common inhabitans were fungi from genus Alternaria (mainly A. alternata and A. radicina and Fusarium, especially F. avenaceum and F. oxysporum. During the glasshouse investigations fungi Alternaria radicina, A. alternata and Fusarium avenaceum were the main reason for parsley damping-off. The highest number of infected seedlings was observed for Berlińska and Kinga, because in both years of experiments these cultivars had the lowest number of healthy seedlings. The highest number of healthy seedlings had cultivars Alba and Lenka, especially in the second year of experiments. In the field experiments not only fungi from genus Alternaria and Fusarium were the most often isolated from diseased parsley seedlings. Fusarium oxysporum was more often isolated from diseased field seedlings than from glasshouse parsley seedlings. Other fungies isolated often from parsley seedlings cultivated in the field were: Pythium spp., Rhizoctonia solani, Cylindrocarpon destructans and Stemphylium botryosum.

Fungi isolated from Stewartia pseudocamellia Max. seeds and their pathogenesis

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Halina Kurzawińska

2012-12-01

Full Text Available The aim of studies was to determine typical composition of fungi occurring on seeds of Stewartia pseudocamellia.The studies conducted on 100 disinfected and 100 nondisinfected seeds of these plants.Isolates of Alternaria alternata, Fusarium oxysporum, Cylindrocarpon radicicola and Rhizoctonia solani were characterized by pathogenicity towards the investigated Stewartia pseudocamellia. In the laboratory experiment, 204 isolations of microorganisms were obtained that belonged to 20 species and form of fungi and bacteria. Among fungi there were both of parasite (Alternaria alternata, Botrytis cinerea, Fusarium spp., Rhizoctonia solani and typical saprophytic (Cladosporium spp., Penicillium spp., Aspergillus spp., Epicoccum spp., Mucor spp.. The dominant fungus on seeds was Alternaria alternata. Among the investigated isolates only one isolate (R4 Rhizoctonia solani, was strongly pathogenic, isolates (A1 Alternaria alternata were weakly pathogenic to seedlings of Stewartia pseudocamellia.

Use of DNA sequencing to detect pathogenic, saprotrophic, and stain fungi in sapwood of declining red pine (Pinus resinosa) in the Upper Midwest

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M.T. Banik; D.L. Lindner; J. Juzwik; J.A. Glaeser

2013-01-01

An inexpensive kit was developed to collect wood samples for molecular detection of pathogenic, saprotrophic and stain fungi in declining Pinus resinosa in the Upper Midwest. The kit contained materials for "clean" collection of sapwood drill shavings, which were then subjected to PCR of the rDNA ITS region with fungal-specific primers,...

Thailandins A and B, New Polyene Macrolactone Compounds Isolated from Actinokineospora bangkokensis Strain 44EHW(T), Possessing Antifungal Activity against Anthracnose Fungi and Pathogenic Yeasts.

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Intra, Bungonsiri; Greule, Anja; Bechthold, Andreas; Euanorasetr, Jirayut; Paululat, Thomas; Panbangred, Watanalai

2016-06-29

Two new polyene macrolactone antibiotics, thailandins A, 1, and B, 2, were isolated from the fermentation broth of rhizosphere soil-associated Actinokineospora bangkokensis strain 44EHW(T). The new compounds from this strain were purified using semipreparative HPLC and Sephadex LH-20 gel filtration while following an antifungal activity guided fractionation. Their structures were elucidated through spectroscopic techniques including UV, HR-ESI-MS, and NMR. These compounds demonstrated broad spectrum antifungal activity against fungi causing anthracnose disease (Colletotrichum gloeosporioides DoA d0762, Colletotrichum gloeosporiodes DoA c1060, and Colletotrichum capsici DoA c1511) as well as pathogenic yeasts (Candida albicans MT 2013/1, Candida parasilopsis DKMU 434, and Cryptococcus neoformans MT 2013/2) with minimum inhibitory concentrations ranging between 16 and 32 μg/mL. This is the first report of polyene antibiotics produced by Actinokineospora species as bioactive compounds against anthracnose fungi and pathogenic yeast strains.

Soil eukaryotic microorganism succession as affected by continuous cropping of peanut--pathogenic and beneficial fungi were selected.

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Mingna Chen

Full Text Available Peanut is an important oil crop worldwide and shows considerable adaptability but growth and yield are negatively affected by continuous cropping. Soil micro-organisms are efficient bio-indicators of soil quality and plant health and are critical to the sustainability of soil-based ecosystem function and to successful plant growth. In this study, 18S rRNA gene clone library analyses were employed to study the succession progress of soil eukaryotic micro-organisms under continuous peanut cultivation. Eight libraries were constructed for peanut over three continuous cropping cycles and its representative growth stages. Cluster analyses indicated that soil micro-eukaryotic assemblages obtained from the same peanut cropping cycle were similar, regardless of growth period. Six eukaryotic groups were found and fungi predominated in all libraries. The fungal populations showed significant dynamic change and overall diversity increased over time under continuous peanut cropping. The abundance and/or diversity of clones affiliated with Eurotiales, Hypocreales, Glomerales, Orbiliales, Mucorales and Tremellales showed an increasing trend with continuous cropping but clones affiliated with Agaricales, Cantharellales, Pezizales and Pyxidiophorales decreased in abundance and/or diversity over time. The current data, along with data from previous studies, demonstrated that the soil microbial community was affected by continuous cropping, in particular, the pathogenic and beneficial fungi that were positively selected over time, which is commonplace in agro-ecosystems. The trend towards an increase in fungal pathogens and simplification of the beneficial fungal community could be important factors contributing to the decline in peanut growth and yield over many years of continuous cropping.

Identification of virulence determinants of the human pathogenic fungi Aspergillus fumigatus and Candida albicans by proteomics.

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Kniemeyer, Olaf; Schmidt, André D; Vödisch, Martin; Wartenberg, Dirk; Brakhage, Axel A

2011-06-01

Both fungi Candida albicans and Aspergillus fumigatus can cause a number of life-threatening systemic infections in humans. The commensal yeast C. albicans is one of the main causes of nosocomial fungal infectious diseases, whereas the filamentous fungus A. fumigatus has become one of the most prevalent airborne fungal pathogens. Early diagnosis of these fungal infections is challenging, only a limited number of antifungals for treatment are available, and the molecular details of pathogenicity are hardly understood. The completion of both the A. fumigatus and C. albicans genome sequence provides the opportunity to improve diagnosis, to define new drug targets, to understand the functions of many uncharacterised proteins, and to study protein regulation on a global scale. With the application of proteomic tools, particularly two-dimensional gel electrophoresis and LC/MS-based methods, a comprehensive overview about the proteins of A. fumigatus and C. albicans present or induced during environmental changes and stress conditions has been obtained in the past 5 years. However, for the discovery of further putative virulence determinants, more sensitive and targeted proteomic methods have to be applied. Here, we review the recent proteome data generated for A. fumigatus and C. albicans that are related to factors required for pathogenicity. Copyright © 2011 Elsevier GmbH. All rights reserved.

Thermophilic Fungi to Dominate Aflatoxigenic/Mycotoxigenic Fungi on Food under Global Warming

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Robert Russell M. Paterson

2017-02-01

Full Text Available Certain filamentous fungi produce mycotoxins that contaminate food. Mycotoxin contamination of crops is highly influenced by environmental conditions and is already affected by global warming, where there is a succession of mycotoxigenic fungi towards those that have higher optimal growth temperatures. Aflatoxigenic fungi are at the highest limit of temperature although predicted increases in temperature are beyond that constraint. The present paper discusses what will succeed these fungi and represents the first such consideration. Aflatoxins are the most important mycotoxins and are common in tropical produce, much of which is exported to temperate regions. Hot countries may produce safer food under climate change because aflatoxigenic fungi will be inhibited. The same situation will occur in previously temperate regions where these fungi have recently appeared, although decades later. Existing thermotolerant and thermophilic fungi (TTF will dominate, in contrast to the conventional mycotoxigenic fungi adapting or mutating, as it will be quicker. TTF produce a range of secondary metabolites, or potential mycotoxins and patulin which may become a new threat. In addition, Aspergillus fumigatus will appear more frequently, a serious human pathogen, because it is (a thermotolerant and (b present on crops: hence this is an even greater problem. An incubation temperature of 41 °C needs employing forthwith to detect TTF. Finally, TTF in crops requires study because of the potential for diseases in humans and animals under climate change.

Distribution of ectomycorrhizal and pathogenic fungi in soil along a vegetational change from Japanese black pine (Pinus thunbergii) to black locust (Robinia pseudoacacia).

Science.gov (United States)

Taniguchi, Takeshi; Kataoka, Ryota; Tamai, Shigenobu; Yamanaka, Norikazu; Futai, Kazuyoshi

2009-04-01

The nitrogen-fixing tree black locust (Robinia pseudoacacia L.) seems to affect ectomycorrhizal (ECM) colonization and disease severity of Japanese black pine (Pinus thunbergii Parl.) seedlings. We examined the effect of black locust on the distribution of ECM and pathogenic fungi in soil. DNA was extracted from soil at depths of 0-5 and 5-10 cm, collected from the border between a Japanese black pine- and a black locust-dominated forest, and the distribution of these fungi was investigated by denaturing gradient gel electrophoresis. The effect of soil nutrition and pH on fungal distribution was also examined. Tomentella sp. 1 and Tomentella sp. 2 were not detected from some subplots in the Japanese black pine-dominated forest. Ectomycorrhizas formed by Tomentella spp. were dominant in black locust-dominated subplots and very little in the Japanese black pine-dominated forest. Therefore, the distribution may be influenced by the distribution of inoculum potential, although we could not detect significant relationships between the distribution of Tomentella spp. on pine seedlings and in soils. The other ECM fungi were detected in soils in subplots where the ECM fungi was not detected on pine seedlings, and there was no significant correlation between the distribution of the ECM fungi on pine seedlings and in soils. Therefore, inoculum potential seemed to not always influence the ECM community on roots. The distribution of Lactarius quieticolor and Tomentella sp. 2 in soil at a depth of 0-5 cm positively correlated with soil phosphate (soil P) and that of Tomentella sp. 2 also positively correlated with soil nitrogen (soil N). These results suggest the possibility that the distribution of inoculum potential of the ECM fungi was affected by soil N and soil P. Although the mortality of the pine seedlings was higher in the black locust-dominated area than in the Japanese black pine-dominated area, a pathogenic fungus of pine seedlings, Cylindrocladium pacificum, was

Virulence Factors IN Fungi OF Systemic Mycoses

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KUROKAWA Cilmery Suemi

1998-01-01

Full Text Available Pathogenic fungi that cause systemic mycoses retain several factors which allow their growth in adverse conditions provided by the host, leading to the establishment of the parasitic relationship and contributing to disease development. These factors are known as virulence factors which favor the infection process and the pathogenesis of the mycoses. The present study evaluates the virulence factors of pathogenic fungi such as Blastomyces dermatitidis, Coccidioides immitis, Cryptococcus neoformans, Histoplasma capsulatum and Paracoccidioides brasiliensis in terms of thermotolerance, dimorphism, capsule or cell wall components as well as enzyme production. Virulence factors favor fungal adhesion, colonization, dissemination and the ability to survive in hostile environments and elude the immune response mechanisms of the host. Both the virulence factors presented by different fungi and the defense mechanisms provided by the host require action and interaction of complex processes whose knowledge allows a better understanding of the pathogenesis of systemic mycoses.

[Mutant prevention concentrations of antibacterial agents to ocular pathogenic bacteria].

Science.gov (United States)

Liang, Qing-Feng; Wang, Zhi-Qun; Li, Ran; Luo, Shi-Yun; Deng, Shi-Jing; Sun, Xu-Guang

2009-01-01

To establish a method to measure mutant prevention concentration (MPC) in vitro, and to measure MPC of antibacterial agents for ocular bacteria caused keratitis. It was an experimental study. Forty strains of ocular bacteria were separated from cornea in Beijing Institute of Ophthalmology, which included 8 strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Pseudomonas aeruginosa and Klebsiella pneumoniae respectively. The minimal inhibitory concentration (MIC) of the levofloxacin (LVF), ofloxacin (OFL), ciprofloxacin (CIP), norfloxacin (NFL), tobramycin (TOB) and chloromycetin (CHL) were determined by agar dilution method from National Committee of Clinical Laboratory Standard (NCCLS). The MPC were measured by accumulate-bacterial methods with bacterial population inoculated more than 1.2 x 10(10) colony forming units per milliliter with Mueller-Hinton broth and tryptic soy agar plate. With the software of SPSS 11.0, the datum such as the range of MIC, MPC, MIC90 and MPC90 were calculated, and the selection index (MPC90/ MI90) and mutant selection window (MSW) were obtained. The MI90 of LVF and TOB (4 mg/L) to Staphylococcus aureus strains were the lowest. CIP showed the lowest MIC90 (0.25 mg/L) to Pseudomonas aeruginosa among six kinds of antibacterial agents. The MIC90 of LVF to Staphylococcus epidermidis (256 mg/L), Streptococcus pneumoniae (1 mg/L) and Klebsiella pneumoniae (0.25 mg/L) were lower than other antibacterial agents. The MPC90, MSW and the MPC90/MIC90 of levofloxacin showed lower values compared with other antibacterial medicines. From all the datum, the MIC90 of CHL was the highest and the activity was the weakest. Although the activity of LVF was higher to every kind of bacteria, CIP had the highest activity antibacterial to Pseudomonas aeruginosa. The capacity of CHL and TOB was weaker than Quinolones for restricting resistant mutants on ocular bacteria. LVF had the strongest capacity for restricting resistant

Hijacked: Co-option of host behavior by entomophthoralean fungi

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Over 700 species of fungi are known to infect and cause disease in insects and other arthropods. The majority of insect pathogenic fungi are classified in the phyla Entomophthoromycotina and Ascomycotina, and many are ecologically important in regulating insect populations. To summarize fungal-inse...

Filamentous Growth in Eremothecium Fungi

DEFF Research Database (Denmark)

Oskarsson, Therese

, this thesis deals with some of the aspects of hyphal growth, which is an important virulence factor for pathogenic fungi infecting both humans and plants. Hyphal establishment through continuous polar growth is a complex process, requiring the careful coordination of a large subset of proteins involved......-regulatory activity of AgGts1, the protein could have additional actin organizing properties. In the second and third part, this thesis addresses the use of A. gossypii and its relative E. cymbalariae as model organisms for filamentous growth. A series of assays analyzed the capability of Eremothecium genus fungi...... of molecular tools for E. cymbalariae to enable a faster and more efficient approach for genetic comparisons between Eremothecium genus fungi....

Occurrence of pathogenic fungi to Amblyomma cajennense in a rural area of Central Brazil and their activities against vectors of Rocky Mountain spotted fever.

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D'Alessandro, Walmirton B; Humber, Richard A; Luz, Christian

2012-08-13

Two isolates of Beauveria bassiana and one of Purpureocillium lilacinum (=Paecilomyces lilacinus) were found infecting Amblyomma cajennense engorged females collected on horses (0.15% infection rate from a total of 1982 specimens) and another two isolates of P. lilacinum and one Metarhizium anisopliae detected in soils (2.1% from 144 samples) collected in typical pasture habitats of this tick in Central Brazil from October 2009 to March 2011. Fungi were isolated from soils with Rhipicephalus sanguineus as surrogate baits. No fungi were found in ticks or soils during the driest months (May to August). Testing pathogenicity of fungi all R. sanguineus females were killed regardless of the isolate and fungi sporulated abundantly on the cadavers. A. cajennense was less susceptible to infection with P. lilacinum within 20 days than R. sanguineus. All three fungal species probably act as natural antagonists of A. cajennense particularly in the rainy season and have interest for integrate control of vectors of Rocky Mountain spotted fever. Copyright © 2012 Elsevier B.V. All rights reserved.

Isolation and evaluation of endophytic fungi with antimicrobial ability from Phyllostachys edulis

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Xiaoye Shen

2012-12-01

Full Text Available Endophytic fungi (30 isolates from bamboo branches were categorized into 12 genera, based on the blast analyses of ITS nrDNA sequence in GenBank and microscopic examination. The aim of this work was to investigate the antibacterial and antifungal activities of endophytic fungi. Inhibitory effects against clinical pathogens and phytopathogens have been screened for all the isolates preliminarily and strains tentatively identified as Cladosporium sphaerospermum (PE106, Simplicillium lanosoniveum (PE120, Curvularia sp. (PE127, Didymella sp. (PE128 and Penicillium cf. raistrickii (PE130 presented bioactivity against at least four tested pathogens using the agar diffusion method. Crude extracts of PE106, PE120, PE127 and PE130 displayed broad-spectrum activity against plant pathogenic fungi by mycelial radial growth test. All of the four isolates were found to have high bioactivity against the frequent plant pathogenic fungus Botryotinia fuckeliana, and two of the isolates (PE120 and PE130 also inhibited the growth of phytopathogen Thanatephorus cucumeris noteworthily. This study is the first report on the antimicrobial activity of endophytic fungi associated with branches of Ph. edulis.

Isolation and Identification of Pathogenic Fungi from Air Conditioners in Tutorial Rooms of the Faculty of Medicine, Universitas Padjadjaran

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Gowre Govindasamy

2014-02-01

Full Text Available Background: Awareness about health problems caused by air conditioner is very important. Thus, it is crucial to have knowledge about proper maintenance of air conditioner. At the Faculty of Medicine, Universitas Padjadjaran, air conditioners are used in every tutorial rooms. This study was performed to provide adequate information on the fungi, such as Aspergillus, Penicillium and Mucor, found in air conditioners. Methods: A descriptive laboratory study was used to identify the presence and the type of pathogenic fungi from air conditioners in tutorial rooms. Thirty-four samples were collected from the air outlet grille of the air conditioners and cultured on Sabouraud agar at 27°C for 2 weeks. Fungi presence were then identified microscopically Results: The results showed that the majority of air conditioners in tutorial rooms of the Faculty of Medicine, University Padjadjaran contained many types of fungus that grew in Sabouraud agar. From 34 samples, thirty two samples were positive and 2 samples were negative. Various fungus have been identified, those were Penicillium (37.5%, Aspergillus (25%, Mucor (2.5% and unidentified (35% Conclusions : The majority of air conditioners in tutorial rooms of the Faculty of Medicine, University Padjadjaran contained many types of opportunistic fungus. [AMJ.2014;1(1:21–4

[An example of research on biological control: Entomophthora fungi pathogenic for aphids].

Science.gov (United States)

Latgé, J P; Remaudière, G; Papierok, B

1978-01-01

The results obtained in 15 years of research on the Entomophthorales pathogen of aphids showed the importance of the action of these fungi in the regulation of natural aphid populations and their possible use in agriculture as a biological control agent. Recent ecological studies on natural populations of aphids established the seasonal variation of the different fungal species and the diverse degrees of specificity between the species or groups of species of aphid and the various species of Entomophthora. The study of populations dynamics of an aphid species on a cultivated plant permitted the determination of the way a certain number of biotic and abiotic factors, such as temperature, humidity, thresholds of the insect population and of the infecting fungus lead to an epizootic development. If the air propagation of the disease by conidia is understood for a long time, the role of the soil as a reservoir for the infecting fungus has been demonstrated recently. Under favourable climatic conditions, the use of industrially produced resistant resting spores would allow the regulation of aphid populations in nature.

Culturable fungi in potting soils and compost.

Science.gov (United States)

Haas, Doris; Lesch, Susanne; Buzina, Walter; Galler, Herbert; Gutschi, Anna Maria; Habib, Juliana; Pfeifer, Bettina; Luxner, Josefa; Reinthaler, Franz F

2016-11-01

In the present study the spectrum and the incidence of fungi in potting soils and compost was investigated. Since soil is one of the most important biotopes for fungi, relatively high concentrations of fungal propagules are to be expected. For detection of fungi, samples of commercial soils, compost and soils from potted plants (both surface and sub-surface) were suspended and plated onto several mycological media. The resulting colonies were evaluated qualitatively and quantitatively. The results from the different sampling series vary, but concentrations on the surface of potted plants and in commercial soils are increased tenfold compared to compost and sub-surface soils. Median values range from 9.5 × 10(4) colony forming units (CFU)/g to 5.5 × 10(5) CFU/g. The spectrum of fungi also varies in the soils. However, all sampling series show high proportion of Aspergillus and Penicillium species, including potentially pathogenic species such as Aspergillus fumigatus. Cladosporium, a genus dominant in the ambient air, was found preferably in samples which were in contact with the air. The results show that potentially pathogenic fungi are present in soils. Immunocompromised individuals should avoid handling soils or potted plants in their immediate vicinity. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Use of bacillus subtilis strains to inhibit postharvest pathogenic fungi

International Nuclear Information System (INIS)

Arras, G.; Gambella, F.; Demontis, S.; Petretto, A.

1995-01-01

An isolate (87) of the bacillus subtilis strains isolated from cold stored citrus fruit 13 proved to inhibit the growth in vitro of the penicillium italicum used in the experiment (from 50.6% to 92.2%) and to inhibit botrytis cinerea (from 65.3% to 95.9%). A further test, superimposing on plates containing PDA strains Nos. 13, 173, and 160, totally inhibited the fungi. Tested in vivo on artificially bruised oranges, they significantly inhibited two fungi

Phylogeny and comparative genome analysis of a Basidiomycete fungi

Energy Technology Data Exchange (ETDEWEB)

Riley, Robert W.; Salamov, Asaf; Grigoriev, Igor; Hibbett, David

2011-03-14

Fungi of the phylum Basidiomycota, make up some 37percent of the described fungi, and are important from the perspectives of forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, plant pathogenic rusts and smuts, and some human pathogens. To better understand these important fungi, we have undertaken a comparative genomic analysis of the Basidiomycetes with available sequenced genomes. We report a phylogeny that sheds light on previously unclear evolutionary relationships among the Basidiomycetes. We also define a `core proteome? based on protein families conserved in all Basidiomycetes. We identify key expansions and contractions in protein families that may be responsible for the degradation of plant biomass such as cellulose, hemicellulose, and lignin. Finally, we speculate as to the genomic changes that drove such expansions and contractions.

The effect of ectomycorrhizal fungi and bacteria on pine seedlings

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Hanna Dahm

2014-08-01

Full Text Available The effect of ecomycorrhizal fungi (Hebelon crustuliniforme(Bull.: Fr. Quél. 5392 and Pisolithus tinctorius (Pers. Coker et Couch 5335 and bacteria (Bacillus polymyxa and Azospirillum brasilense. associated with mycorrhizas on the growth of pine seedligs was investigated. In addition the influence of bacteria on fungal biomass production and the relationship between ectomycorrhizal fungi and fungi pathogenic to root of pine seedlings were determined. In general, the shoot/root ratio was higher in plants inoculated with Hebeloma crustuliniforme and bacteria than in the control seedlings (grown only under sterile conditions. In non-sterile substrate the root/shoot ratio of the mycorrhizal seedlings was lower as compared to the control. Similar phenomenon was noted in plants inoculated with the mycorrhizal fungus Pisolithus tinetorius. The bacteria used as well as the time of introduction of these organisms into the cultures of mycorrhiza fungi affected the production of fungal biomass. Hebeloma crustuliniforme and Pisolithus tinctorius inhibited the growth of Rizoctonia solani and Fusarium oxysporum fungi pathogenic to pine seedlings.

Investigations on the effects of triazole group fungicides on some important antagonistic fungi and non-pathogen Fusarium oxysporum (Schlecht) in vitro.

OpenAIRE

Demirci, A.; Katırcıoğlu, Z.; Demirci, F.

2008-01-01

The effects of eight triazole fungicides (cyproconazole, diniconazole, flusilazole hexaconazole, myclobutanil, penconazole, tebuconazole and triticinazole) on some important antagonistic fungi [Trichoderma harzianum (Rifai), T. viride (Pers. ex Gray), T. pseudokoningii (Rifai), T. hamatum (Bonard), Gliociadium viride (Matrouchot), Aspergillus niger (Tieghem), Penicillium verrııcosum (Dierckx)] and non-pathogen Fusarium oxysporum (Schlecht) were investigated on PDA in vitro. EC5 0 values ...

Effect of ectomycorrhizal fungi in the protection of Uapaca kirkiana ...

African Journals Online (AJOL)

Investigations carried out on the use of ectomycorhhizal fungi in the management of Uapaca kirkiana root diseases caused by three pathogens (Rhizoctonia solani, Phytophthora parasitica and Pseudomonas solani) revealed that different mycorrhizal fungi vary in their ability to protect roots against these respective ...

Antifungal activity of nettle (Urtica dioica L.), colocynth (Citrullus colocynthis L. Schrad), oleander (Nerium oleander L.) and konar (Ziziphus spina-christi L.) extracts on plants pathogenic fungi.

Science.gov (United States)

Hadizadeh, I; Peivastegan, B; Kolahi, M

2009-01-01

Anti-mycotic activity of the ethanol extracts from Nettle (Urtica dioica L.), Colocynth (Citrullus colocynthis L. Schrad), Konar (Ziziphus spina-christi L.) and Oleander (Nerium oleander L.) floral parts were screened in vitro against four important plant pathogenic fungi viz.; Alternaria alternate, Fusarium oxysporum, Fusarium solani and Rizoctonia solani using agar dilution bioassay. Extracts showed antifungal activity against all the tested fungi. Among the plants, Nettle and Colocynth were the most effective against A. alternate and R. solani while Oleander possesses the best inhibition on F. oxysporum and F. solani. Konar was the most effective extract by reducing the growth of Rizoctonia solani than other fungi. These results showed that extracts could be considered suitable alternatives to chemical additives for the control of fungal diseases in plants.

[Antagonism in vitro among phytopathogenic and saprobic fungi from horticultural soils].

Science.gov (United States)

Alippi, H E; Monaco, C

1990-01-01

Two methods were tested in order to determine the existence of in vitro antagonism among saprobic and pathogenic fungi. These microorganisms were the most common isolates from horticultural soils of La Plata (Buenos Aires). Trichoderma harzianum; T. koningii and Penicillium sp. were antagonistic to all the pathogenic fungi tested, Fusarium solani; F. oxysporum; Alternaria solani; Colletotrichum sp. and Sclerotium rolfsii Spicaria sp., Paecilomyces sp. and Chaetomiun sp. were antagonistic only to Colletotrichum sp. and Fusarium solani.

Support of the Laboratory in the Diagnosis of Fungal Ocular Infections

Science.gov (United States)

Vanzzini Zago, Virginia; Alcantara Castro, Marino; Naranjo Tackman, Ramon

2012-01-01

This is a retrospective, and descriptive study about the support that the laboratory of microbiology aids can provide in the diagnosis of ocular infections in patients whom were attended a tertiary-care hospital in México City in a 10-year-time period. We describe the microbiological diagnosis in palpebral mycose; in keratitis caused by Fusarium, Aspergillus, Candida, and melanized fungi; endophthalmitis; one Histoplasma scleritis and one mucormycosis. Nowadays, ocular fungal infections are more often diagnosed, because there is more clinical suspicion and there are easy laboratory confirmations. Correct diagnosis is important because an early medical treatment gives a better prognosis for visual acuity. In some cases, fungal infections are misdiagnosed and the antifungal treatment is delayed. PMID:22518339

Vertebrate Endothermy Restricts Most Fungi as Potential Pathogens

NARCIS (Netherlands)

Robert, V.A.R.G.; Casadevall, A.

2009-01-01

The paucity of fungal diseases in mammals relative to insects, amphibians, and plants is puzzling. We analyzed the thermal tolerance of 4802 fungal strains from 144 genera and found that most cannot grow at mammalian temperatures. Fungi from insects and mammals had greater thermal tolerances than

Genome Studies on Nematophagous and Entomogenous Fungi in China

Science.gov (United States)

Zhang, Weiwei; Cheng, Xiaoli; Liu, Xingzhong; Xiang, Meichun

2016-01-01

The nematophagous and entomogenous fungi are natural enemies of nematodes and insects and have been utilized by humans to control agricultural and forestry pests. Some of these fungi have been or are being developed as biological control agents in China and worldwide. Several important nematophagous and entomogenous fungi, including nematode-trapping fungi (Arthrobotrys oligospora and Drechslerella stenobrocha), nematode endoparasite (Hirsutella minnesotensis), insect pathogens (Beauveria bassiana and Metarhizium spp.) and Chinese medicinal fungi (Ophiocordyceps sinensis and Cordyceps militaris), have been genome sequenced and extensively analyzed in China. The biology, evolution, and pharmaceutical application of these fungi and their interacting with host nematodes and insects revealed by genomes, comparing genomes coupled with transcriptomes are summarized and reviewed in this paper. PMID:29376926

Tools to kill: Genome of one of the most destructive plant pathogenic fungi Macrophomina phaseolina

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Islam Md

2012-09-01

Full Text Available Abstract Background Macrophomina phaseolina is one of the most destructive necrotrophic fungal pathogens that infect more than 500 plant species throughout the world. It can grow rapidly in infected plants and subsequently produces a large amount of sclerotia that plugs the vessels, resulting in wilting of the plant. Results We sequenced and assembled ~49 Mb into 15 super-scaffolds covering 92.83% of the M. phaseolina genome. We predict 14,249 open reading frames (ORFs of which 9,934 are validated by the transcriptome. This phytopathogen has an abundance of secreted oxidases, peroxidases, and hydrolytic enzymes for degrading cell wall polysaccharides and lignocelluloses to penetrate into the host tissue. To overcome the host plant defense response, M. phaseolina encodes a significant number of P450s, MFS type membrane transporters, glycosidases, transposases, and secondary metabolites in comparison to all sequenced ascomycete species. A strikingly distinct set of carbohydrate esterases (CE are present in M. phaseolina, with the CE9 and CE10 families remarkably higher than any other fungi. The phenotypic microarray data indicates that M. phaseolina can adapt to a wide range of osmotic and pH environments. As a broad host range pathogen, M. phaseolina possesses a large number of pathogen-host interaction genes including those for adhesion, signal transduction, cell wall breakdown, purine biosynthesis, and potent mycotoxin patulin. Conclusions The M. phaseolina genome provides a framework of the infection process at the cytological and molecular level which uses a diverse arsenal of enzymatic and toxin tools to destroy the host plants. Further understanding of the M. phaseolina genome-based plant-pathogen interactions will be instrumental in designing rational strategies for disease control, essential to ensuring global agricultural crop production and security.

Tools to kill: genome of one of the most destructive plant pathogenic fungi Macrophomina phaseolina.

Science.gov (United States)

Islam, Md Shahidul; Haque, Md Samiul; Islam, Mohammad Moinul; Emdad, Emdadul Mannan; Halim, Abdul; Hossen, Quazi Md Mosaddeque; Hossain, Md Zakir; Ahmed, Borhan; Rahim, Sifatur; Rahman, Md Sharifur; Alam, Md Monjurul; Hou, Shaobin; Wan, Xuehua; Saito, Jennifer A; Alam, Maqsudul

2012-09-19

Macrophomina phaseolina is one of the most destructive necrotrophic fungal pathogens that infect more than 500 plant species throughout the world. It can grow rapidly in infected plants and subsequently produces a large amount of sclerotia that plugs the vessels, resulting in wilting of the plant. We sequenced and assembled ~49 Mb into 15 super-scaffolds covering 92.83% of the M. phaseolina genome. We predict 14,249 open reading frames (ORFs) of which 9,934 are validated by the transcriptome. This phytopathogen has an abundance of secreted oxidases, peroxidases, and hydrolytic enzymes for degrading cell wall polysaccharides and lignocelluloses to penetrate into the host tissue. To overcome the host plant defense response, M. phaseolina encodes a significant number of P450s, MFS type membrane transporters, glycosidases, transposases, and secondary metabolites in comparison to all sequenced ascomycete species. A strikingly distinct set of carbohydrate esterases (CE) are present in M. phaseolina, with the CE9 and CE10 families remarkably higher than any other fungi. The phenotypic microarray data indicates that M. phaseolina can adapt to a wide range of osmotic and pH environments. As a broad host range pathogen, M. phaseolina possesses a large number of pathogen-host interaction genes including those for adhesion, signal transduction, cell wall breakdown, purine biosynthesis, and potent mycotoxin patulin. The M. phaseolina genome provides a framework of the infection process at the cytological and molecular level which uses a diverse arsenal of enzymatic and toxin tools to destroy the host plants. Further understanding of the M. phaseolina genome-based plant-pathogen interactions will be instrumental in designing rational strategies for disease control, essential to ensuring global agricultural crop production and security.

Pathogenicity gene variations within the order Entomophthorales

DEFF Research Database (Denmark)

Grell, Morten Nedergaard; Jensen, Annette Bruun; Lange, Lene

Fungi within the order Entomophthorales (subphylum Entomophthoromycotina) are obligate biotrophic pathogens of arthropods with a remarkable narrow host range. Infection takes place through the cuticle when conidia hit a susceptible host, facilitated by enzymatic and mechanical mechanisms. In the ...... pathogenicity genes within genera Entomophthora and Pandora, using fungal genomic DNA originating from field-collected, infected insect host species of dipteran (flies, mosquitoes) or hemipteran (aphid) origin.......Fungi within the order Entomophthorales (subphylum Entomophthoromycotina) are obligate biotrophic pathogens of arthropods with a remarkable narrow host range. Infection takes place through the cuticle when conidia hit a susceptible host, facilitated by enzymatic and mechanical mechanisms......, conidia are produced and discharged when humidity gets high—usually during night. In an earlier secretome study of field-collected grain aphids (Sitobion avenae) infected with entomophthoralean fungi, a number of pathogenesis-related, secreted enzymes were discovered (Fungal Genetics and Biology 2011, vol...

Function and Biosynthesis of Cell Wall α-1,3-Glucan in Fungi

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Akira Yoshimi

2017-11-01

Full Text Available Although α-1,3-glucan is a major cell wall polysaccharide in filamentous fungi, its biological functions remain unclear, except that it acts as a virulence factor in animal and plant pathogenic fungi: it conceals cell wall β-glucan on the fungal cell surface to circumvent recognition by hosts. However, cell wall α-1,3-glucan is also present in many of non-pathogenic fungi. Recently, the universal function of α-1,3-glucan as an aggregation factor has been demonstrated. Applications of fungi with modified cell wall α-1,3-glucan in the fermentation industry and of in vitro enzymatically-synthesized α-1,3-glucan in bio-plastics have been developed. This review focuses on the recent progress in our understanding of the biological functions and biosynthetic mechanism of cell wall α-1,3-glucan in fungi. We briefly consider the history of studies on α-1,3-glucan, overview its biological functions and biosynthesis, and finally consider the industrial applications of fungi deficient in α-1,3-glucan.

Laboratory evaluation of temperature effects on the germination and growth of entomopathogenic fungi and on their pathogenicity to two aphid species.

Science.gov (United States)

Yeo, Helen; Pell, Judith K; Alderson, Peter G; Clark, Suzanne J; Pye, Barry J

2003-02-01

As part of an approach to select potential mycoinsecticides for aphid biocontrol, we investigated the effects of temperature on the growth, germination and pathogenicity of some hyphomycete fungi. Commercially available mycoinsecticides (based on Beauveria bassiana (Balsamo) Vuillemin and Verticillium lecanii (Zimmermann) Viegas) and other isolates of B bassiana, V lecanii, Metarhizium anisopliae (Metschnikoff) Sorokin and Paecilomyces fumosoroseus (Wize) Brown & Smith were evaluated. The rate of in vitro conidial germination of all isolates was slower at 10 and 15 degrees C than at 20 and 25 degrees C. Similarly, in vitro growth of most isolates was adversely affected at 10 and 15 degrees C. The greatest reduction at 10 degrees C in rates of conidial germination and colony growth, compared with other temperatures, was for M anisopliae isolates. Germination of V lecanii (isolate HRI 1.72) was fastest at 10 degrees C compared with the other fungi. It was also the most pathogenic of three isolates tested against Aphis fabae Scopoli and Myzus persicae Sulzer at 10, 18 and 23 degrees C. Generally, A fabae was more susceptible than M persicae to infection by the fungal isolates tested. A significant interaction between aphid species and temperature indicated that the pathogenic nature of an isolate was dependent not only on the target aphid species but also the temperature conditions of the bioassay. The series of studies, detailed above, allowed a temperature profile to be formed for the different isolates. Verticillium lecanii isolate HRI 1.72 (commercialised as Vertalec) was the most promising isolate selected from results of the series of experiments. Temperature profiles in conjunction with infectivity assays can be useful in selecting appropriate isolates for a particular thermal environment.

Activity of the pterophyllins 2 and 4 against postharvest fruit pathogenic fungi. Comparison with a synthetic analog and related intermediates.

Science.gov (United States)

Pergomet, Jorgelina L; Di Liberto, Melina G; Derita, Marcos G; Bracca, Andrea B J; Kaufman, Teodoro S

2018-03-01

The antifungal activity of pterophyllin 2, pterophyllin 4, a 5-desmethyl analog of the latter and some of their synthetic intermediates, against three postharvest phytopathogenic fungi, was evaluated. The target fungi were Rhizopus stolonifer, Botrytis cinerea and Monilinia fructicola, which affect fruits worldwide, causing important economic losses. The tests were carried out with imazalil and carbendazim as positive controls. Minimum inhibitory concentrations and minimum fungicidal concentrations were determined, and the morphology of the colonies was examined microscopically. In liquid medium, it was found that pterophyllin 4 exhibited selective fungicidal activity toward M. fructicola, whereas its congener pterophyllin 2 proved to be less potent and not selective and the 5-desmethyl analog of pterophyllin 4 displayed a different activity profile. Morphological changes were observed in the colonies exposed to pterophyllin 4. The results highlighted the importance of small structural features for the antifungal behavior and also suggested that, in Nature, the pterophyllins may act as plant defenses against pathogens. Copyright © 2018 Elsevier B.V. All rights reserved.

Investigating Gene Function in Cereal Rust Fungi by Plant-Mediated Virus-Induced Gene Silencing.

Science.gov (United States)

Panwar, Vinay; Bakkeren, Guus

2017-01-01

Cereal rust fungi are destructive pathogens, threatening grain production worldwide. Targeted breeding for resistance utilizing host resistance genes has been effective. However, breakdown of resistance occurs frequently and continued efforts are needed to understand how these fungi overcome resistance and to expand the range of available resistance genes. Whole genome sequencing, transcriptomic and proteomic studies followed by genome-wide computational and comparative analyses have identified large repertoire of genes in rust fungi among which are candidates predicted to code for pathogenicity and virulence factors. Some of these genes represent defence triggering avirulence effectors. However, functions of most genes still needs to be assessed to understand the biology of these obligate biotrophic pathogens. Since genetic manipulations such as gene deletion and genetic transformation are not yet feasible in rust fungi, performing functional gene studies is challenging. Recently, Host-induced gene silencing (HIGS) has emerged as a useful tool to characterize gene function in rust fungi while infecting and growing in host plants. We utilized Barley stripe mosaic virus-mediated virus induced gene silencing (BSMV-VIGS) to induce HIGS of candidate rust fungal genes in the wheat host to determine their role in plant-fungal interactions. Here, we describe the methods for using BSMV-VIGS in wheat for functional genomics study in cereal rust fungi.

Protecting Plants against Pests and Pathogens with Entomopathogenic Fungi

DEFF Research Database (Denmark)

Keyser, Chad Alton

This thesis investigates the natural occurrence of the fungal genus Metarhizium in association with crop-roots in Denmark, and advances the current understanding of how these fungi interact with other root-associating organisms when applied as a biological control agent. Insect-pest management...... protection. The fungal genus Metarhizium is one of the most intensely researched groups of entomopathogenic fungi and several isolates have been successfully employed as biopesticides for crop protection; however, inconsistent field reliability has limited wider implementation. Research emphasizing...... of the mycoparasitic fungus Clonostachys roseas to control Fusarium culmorum disease in wheat; and a significant level of insect mortality was observed in insects feeding on roots from inoculated seed – even when Metarhizium was applied jointly with C. rosea. Furthermore, M. flavoviride, a less frequently studied...

Seasonality of pathogenic fungi in mites of rubber tree plantations adjacent to fragments of Cerrado

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PR. Demite

Full Text Available Fungi are the most frequently observed pathogens of mite populations, helping to control them on different crops. Twenty-five samples of leaves were collected from rubber tree plantations adjacent to two fragments of Cerrado vegetation. Each rubber tree plantation had 25 plants selected for sampling and seven leaves from around each tree top were collected up to seven to eight meters above ground. Approximately 250 individuals of Calacarus heveae Feres, Phyllocoptruta seringueirae Feres, and Tenuipalpus heveae Baker, collected randomly, were mounted from each plantation. Hirsutella thompsoni Fisher was observed on all three mites and T. heveae was the most infected species. The highest infestation levels occurred from November to February (rainy season. In the dry season, infestation levels were below 5%. Hirsutella thompsonii has potential to be used as mycoacaricide during the rainy season.

Rhizospheric fungi of Panax notoginseng: diversity and antagonism to host phytopathogens

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Cui-Ping Miao

2016-04-01

Conclusion: Our results suggest that diverse fungi including potential pathogenic ones exist in the rhizosphere soil of 2-yr-old P. notoginseng and that antagonistic isolates may be useful for biological control of pathogens.

Characterization of Novel Di-, Tri-, and Tetranucleotide Microsatellite Primers Suitable for Genotyping Various Plant Pathogenic Fungi with Special Emphasis on Fusaria and Mycospherella graminicola

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Joseph-Alexander Verreet

2012-03-01

Full Text Available The goals of this investigation were to identify and evaluate the use of polymorphic microsatellite marker (PMM analysis for molecular typing of seventeen plant pathogenic fungi. Primers for di-, tri-, and tetranucleotide loci were designed directly from the recently published genomic sequence of Mycospherlla graminicola and Fusarium graminearum. A total of 20 new microsatellite primers as easy-to-score markers were developed. Microsatellite primer PCR (MP-PCR yielded highly reproducible and complex genomic fingerprints, with several bands ranging in size from 200 to 3000 bp. Of the 20 primers tested, only (TAGG4, (TCC5 and (CA7T produced a high number of polymorphic bands from either F. graminearum or F. culmorum. (ATG5 led to successful amplifications in M. graminicola isolates collected from Germany. Percentage of polymorphic bands among Fusarium species ranged from 9 to 100%. Cluster analysis of banding patterns of the isolates corresponded well to the established species delineations based on morphology and other methods of phylogenetic analysis. The current research demonstrates that the newly designed microsatellite primers are reliable, sensitive and technically simple tools for assaying genetic variability in plant pathogenic fungi.

An efficient method for DNA extraction from Cladosporioid fungi

OpenAIRE

Moslem, M.A.; Bahkali, A.H.; Abd-Elsalam, K.A.; Wit, de, P.J.G.M.

2010-01-01

We developed an efficient method for DNA extraction from Cladosporioid fungi, which are important fungal plant pathogens. The cell wall of Cladosporioid fungi is often melanized, which makes it difficult to extract DNA from their cells. In order to overcome this we grew these fungi for three days on agar plates and extracted DNA from mycelium mats after manual or electric homogenization. High-quality DNA was isolated, with an A260/A280 ratio ranging between 1.6 and 2.0. Isolated genomic DNA w...

Fluorescent Staining of Tea Pathogenic Fungi in Tea Leaves Using Fluorescein-labeled Lectin

Science.gov (United States)

Yamada, Kengo; Yoshida, Katsuyuki; Sonoda, Ryoichi

Fluorochrome-labeled lectin, fluorescein conjugated wheat germ agglutinin (F-WGA) was applied to stain tea pathogenic fungi in tea leaf tissue. Infected leaves were fixed and decolorized with a mixture of ethanol and acetic acid, and cleared with 10% KOH for whole mount before staining with F-WGA. Hyphae of Pestalotiopsis longiseta, Pseudocercospora ocellata, Botrytis cinerea and Colletotrichum theae-sinensis fluoresced brightly in whole mount and sectioned samples of infected leaf tissue. In browned tissue, hyphae did not fluoresce frequently in whole mount sample. Autofluorescence of leaf tissue was strong in browned tissue of sections, it was removed by 10% KOH treatment before staining. Penetration hyphae of C. theae-sinensis in cell wall of trichome and hyphae in basal part of trichome did not fluoresced frequently. In whole mount samples of tea leaf infected with Exobasidium vexans and E. reticulatum, hymenia appeared on leaf surface fluoresced, but hyphae in leaf tissue did not fluoresce. In sectioned samples, hyphae fluoresced brightly when sections were treated with 10% KOH before staining.

Influence of temperature, precipitation, and cultivar characteristics on changes in the spectrum of pathogenic fungi in winter wheat.

Science.gov (United States)

Hýsek, Josef; Vavera, Radek; Růžek, Pavel

2017-06-01

In view of the threat posed by climate change, we studied the influence of temperature, precipitation, cultivar characteristics, and technical management measures on the occurrence of phytopathogenic fungi in wheat during 2009-2013. This work involved experiments at two sites differing in average temperatures and precipitation. Temperature and precipitation appear to influence differences in the spectrum of phytopathogenic fungi at the individual sites. In 2009 (the warmest year), Alternaria triticina was dominant. In 2010 (having the smallest deviations from the average for individual years), Septoria tritici dominated. In 2011, Puccinia triticina was most prominent, while in 2012, the genus Drechslera (Pyrenophora) and in 2013, S. tritici and Drechslera tritici-repentis (DTR) dominated. Temperature and precipitation levels in the individual spring months (warmer March to May) played a large role, especially for the leaf rust P. triticina in 2011. A change of only 1 °C with different precipitation during a year played a significant role in changing wheat's fungal spectrum. Cluster analysis showed the differences between single pathogenic fungi on wheat in a single year due to temperature and precipitation. Alternaria abundance was strongly influenced by year (p < 0.001) while locality was significant only in certain years (2012, 2013; p = 0.004 and 0.015, respectively). The same factors were revealed to be significant in the case of Puccinia, but locality played a role (p < 0.001) in different years (2011, 2013). The abundance of S. tritici and Pyrenophora tritici-repentis (Drechslera tritici-repentis) was influenced only by year (p < 0.001).

Induced mutation and somatic recombination as tools for genetic analysis and breeding of imperfect fungi

NARCIS (Netherlands)

Bos, C.J.

1986-01-01

Many fungi which are important in Agriculture as plant pathogens or in Biotechnology as producers of organic acids, antibiotics or enzymes, are imperfect fungi. These fungi do not have a sexual stage, which implies that they lack a meiotic recombination mechanism.

However, many

Morphological and molecular identification of filamentous fungi isolated from cosmetic powders

Directory of Open Access Journals (Sweden)

Flavia Cristina Jastale Pinto

2012-12-01

Full Text Available Seven fungi were isolated from 50 samples of cosmetic powders. Morphological analyses and ribosomal DNA Internal Transcribed Spacers sequencing were performed which allowed the discrimination of the isolated fungi as Aspergillus fumigatus, Penicillium sp., and Cladosporium sp. which could have, among their species, potentially pathogenic microorganisms.

Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi

Science.gov (United States)

2013-01-01

Background Fungi produce a variety of carbohydrate activity enzymes (CAZymes) for the degradation of plant polysaccharide materials to facilitate infection and/or gain nutrition. Identifying and comparing CAZymes from fungi with different nutritional modes or infection mechanisms may provide information for better understanding of their life styles and infection models. To date, over hundreds of fungal genomes are publicly available. However, a systematic comparative analysis of fungal CAZymes across the entire fungal kingdom has not been reported. Results In this study, we systemically identified glycoside hydrolases (GHs), polysaccharide lyases (PLs), carbohydrate esterases (CEs), and glycosyltransferases (GTs) as well as carbohydrate-binding modules (CBMs) in the predicted proteomes of 103 representative fungi from Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. Comparative analysis of these CAZymes that play major roles in plant polysaccharide degradation revealed that fungi exhibit tremendous diversity in the number and variety of CAZymes. Among them, some families of GHs and CEs are the most prevalent CAZymes that are distributed in all of the fungi analyzed. Importantly, cellulases of some GH families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also

Ocular Hypertension

Science.gov (United States)

... Español Eye Health / Eye Health A-Z Ocular Hypertension Sections What Is Ocular Hypertension? Ocular Hypertension Causes ... Hypertension Diagnosis Ocular Hypertension Treatment What Is Ocular Hypertension? Leer en Español: ¿Qué es la hipertensión ocular? ...

Distribution and antimicrobial potential of endophytic fungi associated with ethnomedicinal plant Melastoma malabathricum L.

Science.gov (United States)

Mishra, Vineet Kumar; Singh, Garima; Passari, Ajit Kumar; Yadav, Mukesh Kumar; Gupta, Vijai Kumar; Singh, Bhim Pratap

2016-03-01

Distributions of endophytic fungi associated with ethnomedicinal plant Melastoma malabathricum L. was studied and 91 isolates belonging to 18 genera were recovered. The isolates were distributed to sordariomycetes (62.63%), dothideomycetes (19.78%), eurotiomycetes (7.69%), zygomycetes (4.19%), agaricomycetes (1.09%), and mycelia sterilia (4.39%). Based on colony morphology and examination of spores, the isolates were classified into 18 taxa, of which Colletotrichum, Phomopsis and Phoma were dominant, their relative frequencies were 23.07%, 17.58% and 12.08% respectively. The colonization rate of endophytic fungi was determined and found to be significantly higher in leaf segments (50.76%), followed by root (41.53%) and stem tissues (27.69%). All the isolates were screened for antimicrobial activity and revealed that 26.37% endophytic fungi were active against one or more pathogens. Twenty four isolates showing significant antimicrobial activity were identified by sequencing the ITS1-5.8S-ITS2 region of rRNA gene. Results indicated that endophytic fungi associated with leaf were functionally versatile as they showed antimicrobial activity against most of the tested pathogens. The endophytic fungi Diaporthe phaseolorum var. meridionalis (KF193982) inhibited all the tested bacterial pathogens, whereas, Penicillium chermesinum (KM405640) displayed most significant antifungal activity. This seems to be the first hand report to understand the distribution and antimicrobial ability of endophytic fungi from ethno-medicinal plant M. malabathricum.

The diversity of fungi colonizing necrotic inflorescence buds of rhododendron (Rhododendron L.

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Małgorzata Żołna

2013-07-01

Full Text Available The infection of rhododendron (Rhododendron L. inflorescence buds caused by pathogenic fungi induces its browning, withering, and dieback. The identification of fungi causing the infection of rhododendron inflorescence buds can be a reason for creating new improved cultivars with genetically determined resistance to pathogens. The investigations were carried out in 2010–2011 on the collection of ornamental plants of the Faculty of Horticulture, University of Agriculture in Kraków. The material comprised infected inflorescence buds collected from nine newly bred taxa and one botanical species of rhododendron. 596 colonies of fungi belonging to 31 species were isolated from infected rhododendron inflorescence buds. The dominant species were: Pestalotiopsis sydowiana, Truncatella truncata, Alternaria alternata, Phialophora asteris, and Trichoderma viride, which constituted almost 74% of the isolated fungi population. Boeremia exigua var. exigua, Epicoccum nigrum, Fusarium poae, Mammaria echinobotryoides, Paraphoma chrysanthemicola, Phialophora cyclaminis, Phoma eupyrena, Talaromyces wortmannii, Umbelopsis isabellina, and other fungi were isolated in a lower number. The results of mycological analysis confirm the diversity of species colonizing necrotic inflorescence buds of rhododendron. .

Fungi colonizing the soil and roots of tomato (Lycopersicum esculentum Mill. plants treated with biological control agents

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Bożena Cwalina-Ambroziak

2012-12-01

Full Text Available Tomato plants, cv. Rumba Ożarowska, grown in the greenhouse of the University of Warmia and Mazury, were protected in the form of alternate spraying (twice and watering (twice with 5% aqueous extracts of the following plant species: Aloe vulgaris Lam., Achillea millefolium L., Mentha piperita L., Polygonum aviculare L., Equisetum arvense L., Juglans regia L. and Urtica dioica L. Plants not treated with the extracts served as control. After fruit harvest, samples of roots and soil were collected. The roots were disinfected and next placed on PDA medium. Soil-colonizing fungi were cultured on Martin medium. Fungi were identified microscopically after incubation. Pathogenic fungal species, Colletotrichum coccodes, Fusarium equiseti, F. oxysporum and F. poae, accounted for over 60% of all isolates obtained from the roots of tomato plants. The soil fungal community was dominated by yeast-like fungi (75.4%, whereas pathogenic fungi were present in low numbers. The applied 5% aqueous plant extracts effectively reduced the abundance of fungi, including pathogenic species, colonizing tomato plants and soil. The extract from P. aviculare showed the highest efficacy, while the extract from J. regia was least effective. Fungi showing antagonistic activity against pathogens (Paecilomyces roseum and species of the genus Trichoderma were isolated in greatest abundance from the soil and the roots of tomato plants treated with A. millefolium, M. piperita and U. dioica extracts.

Metagenomic analysis of medicinal Cannabis samples; pathogenic bacteria, toxigenic fungi, and beneficial microbes grow in culture-based yeast and mold tests.

Science.gov (United States)

McKernan, Kevin; Spangler, Jessica; Helbert, Yvonne; Lynch, Ryan C; Devitt-Lee, Adrian; Zhang, Lei; Orphe, Wendell; Warner, Jason; Foss, Theodore; Hudalla, Christopher J; Silva, Matthew; Smith, Douglas R

2016-01-01

Background : The presence of bacteria and fungi in medicinal or recreational Cannabis poses a potential threat to consumers if those microbes include pathogenic or toxigenic species. This study evaluated two widely used culture-based platforms for total yeast and mold (TYM) testing marketed by 3M Corporation and Biomérieux, in comparison with a quantitative PCR (qPCR) approach marketed by Medicinal Genomics Corporation. Methods : A set of 15 medicinal Cannabis samples were analyzed using 3M and Biomérieux culture-based platforms and by qPCR to quantify microbial DNA. All samples were then subjected to next-generation sequencing and metagenomics analysis to enumerate the bacteria and fungi present before and after growth on culture-based media. Results : Several pathogenic or toxigenic bacterial and fungal species were identified in proportions of >5% of classified reads on the samples, including Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, Ralstonia pickettii, Salmonella enterica, Stenotrophomonas maltophilia, Aspergillus ostianus, Aspergillus sydowii, Penicillium citrinum and Penicillium steckii. Samples subjected to culture showed substantial shifts in the number and diversity of species present, including the failure of Aspergillus species to grow well on either platform. Substantial growth of Clostridium botulinum and other bacteria were frequently observed on one or both of the culture-based TYM platforms. The presence of plant growth promoting (beneficial) fungal species further influenced the differential growth of species in the microbiome of each sample. Conclusions : These findings have important implications for the Cannabis and food safety testing industries.

Fungi isolated from phyllosphere of fodder galega (Galega orientalis

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Bożena Cwalina-Ambrozik

2013-12-01

Full Text Available The object of the experiment was fodder galega (Galega orientalis Lam. cultivated in 2001-2003 as field crop on three plots: 1. without fertilization, 2. 40 kg P2O5 × ha-1 and 80 kg K2O × ha-1, 3. 80 kg P2O5 × ha-1 and 160 kg K2O × ha-1. During the dry and warm vegetation season of 2002 almost two times fewer isolates were obtained from the leaves than in 2003 that was the most abundant in fungi. Yeasts-like fungi (30% of the total number of isolates and saprotrophic fungi with dominated species: Acremonium strictum (8.5%, genus Epicoccum (7.8%, Humicola (9.5% and Penicillium (18.9% were the fungi most frequently populating the leaves of galega. The share of pathogens in the total number of isolates obtained from the phyllosphere was 10.6%. They were represented by fungi of Ascochyta spp., Botrytis cinerea, genus Fusarium, Phoma medicaginis and Sclerotinia sclerotiorum. Reduction by 1.9 to 4.6% in the number of fungi isolated from the phyllosphere of galega without fertilization as compared to galega cultivated in combinations with fertilization was recorded. Generally, the smallest number of pathogens was recovered from galega fertilized with 40 kg P2O5 × ha-1 and 80 kg K2O × ha-1. B. cinerea most frequently populated galega in combination without fertilization, genus Fusarium fungi in combination without fertilization and with fertilization with 80 kg P2O5 × ha-1 and 160 kg K2O × ha-1, while Ascochyta spp. were isolated from galega with fertilization only.

Diversity of endophytic fungi in Glycine max.

Science.gov (United States)

Fernandes, Elio Gomes; Pereira, Olinto Liparini; da Silva, Cynthia Cânedo; Bento, Claudia Braga Pereira; de Queiroz, Marisa Vieira

2015-12-01

Endophytic fungi are microorganisms that live within plant tissues without causing disease during part of their life cycle. With the isolation and identification of these fungi, new species are being discovered, and ecological relationships with their hosts have also been studied. In Glycine max, limited studies have investigated the isolation and distribution of endophytic fungi throughout leaves and roots. The distribution of these fungi in various plant organs differs in diversity and abundance, even when analyzed using molecular techniques that can evaluate fungal communities in different parts of the plants, such as denaturing gradient gel electrophoresis (DGGE). Our results show there is greater species richness of culturable endophytic filamentous fungi in the leaves G. max as compared to roots. Additionally, the leaves had high values for diversity indices, i.e. Simpsons, Shannon and Equitability. Conversely, dominance index was higher in roots as compared to leaves. The fungi Ampelomyces sp., Cladosporium cladosporioides, Colletotrichum gloeosporioides, Diaporthe helianthi, Guignardia mangiferae and Phoma sp. were more frequently isolated from the leaves, whereas the fungi Fusarium oxysporum, Fusarium solani and Fusarium sp. were prevalent in the roots. However, by evaluating the two communities by DGGE, we concluded that the species richness was higher in the roots than in the leaves. UPGMA analysis showed consistent clustering of isolates; however, the fungus Leptospora rubella, which belongs to the order Dothideales, was grouped among species of the order Pleosporales. The presence of endophytic Fusarium species in G. max roots is unsurprising, since Fusarium spp. isolates have been previously described as endophyte in other reports. However, it remains to be determined whether the G. max Fusarium endophytes are latent pathogens or non-pathogenic forms that benefit the plant. This study provides a broader knowledge of the distribution of the fungal

Multigene phylogeny and taxonomic revision of yeasts and related fungi in the Ustilaginomycotina

NARCIS (Netherlands)

Wang, Q. -M.; Begerow, D.; Groenewald, M.; Liu, X. -Z.; Theelen, B.; Bai, F. -Y.; Boekhout, T.

The subphylum Ustilaginomycotina (Basidiomycota, Fungi) comprises mainly plant pathogenic fungi (smuts). Some of the lineages possess cultivable unicellular stages that are usually classified as yeast or yeast-like species in a largely artificial taxonomic system which is independent from and

Staphylococcus aureus ocular infection: methicillin-resistance, clinical features, and antibiotic susceptibilities.

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Chih-Chun Chuang

Full Text Available BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA infection is an important public health issue. The study aimed to determine the prevalence of ocular infections caused by MRSA and to identify the clinical characteristics and antibiotic susceptibility of ocular MRSA infections by comparing those of ocular methicillin-sensitive S. aureus (MSSA infections. METHODOLOGY/PRINCIPAL FINDINGS: The medical records of the patients (n = 519 with culture-proven S. aureus ocular infections seen between January 1, 1999 and December 31, 2008 in Chang Gung Memorial Hospital were retrospectively reviewed. Two hundred and seventy-four patients with MRSA and 245 with MSSA ocular infections were identified. The average rate of MRSA in S. aureus infections was 52.8% and the trend was stable over the ten years (P value for trend  = 0.228. MRSA ocular infections were significantly more common among the patients with healthcare exposure (P = 0.024, but 66.1% (181/274 patients with MRSA ocular infections had no healthcare exposure. The most common clinical presentation for both MRSA and MSSA ocular infections was keratitis; MRSA and MSSA caused a similar disease spectrum except for lid infections. MRSA was significantly more resistant than MSSA to clindamycin, erythromycin and sulfamethoxazole/trimethoprim (all P<0.001. CONCLUSIONS/SIGNIFICANCE: We demonstrated a paralleled trend of ocular MRSA infection in a highly prevalent MRSA country by hospital-based survey. Except for lid disorder, MRSA shared similar spectrum of ocular pathology with MSSA. Since S. aureus is a common ocular pathogen, our results raise clinician's attention to the existence of highly prevalent MRSA.

Skin Fungi from Colonization to Infection.

Science.gov (United States)

de Hoog, Sybren; Monod, Michel; Dawson, Tom; Boekhout, Teun; Mayser, Peter; Gräser, Yvonne

2017-07-01

Humans are exceptional among vertebrates in that their living tissue is directly exposed to the outside world. In the absence of protective scales, feathers, or fur, the skin has to be highly effective in defending the organism against the gamut of opportunistic fungi surrounding us. Most (sub)cutaneous infections enter the body by implantation through the skin barrier. On intact skin, two types of fungal expansion are noted: (A) colonization by commensals, i.e., growth enabled by conditions prevailing on the skin surface without degradation of tissue, and (B) infection by superficial pathogens that assimilate epidermal keratin and interact with the cellular immune system. In a response-damage framework, all fungi are potentially able to cause disease, as a balance between their natural predilection and the immune status of the host. For this reason, we will not attribute a fixed ecological term to each species, but rather describe them as growing in a commensal state (A) or in a pathogenic state (B).

Post-genomic approaches to understanding interactions between fungi and their environment.

Science.gov (United States)

de Vries, Ronald P; Benoit, Isabelle; Doehlemann, Gunther; Kobayashi, Tetsuo; Magnuson, Jon K; Panisko, Ellen A; Baker, Scott E; Lebrun, Marc-Henri

2011-06-01

Fungi inhabit every natural and anthropogenic environment on Earth. They have highly varied life-styles including saprobes (using only dead biomass as a nutrient source), pathogens (feeding on living biomass), and symbionts (co-existing with other organisms). These distinctions are not absolute as many species employ several life styles (e.g. saprobe and opportunistic pathogen, saprobe and mycorrhiza). To efficiently survive in these different and often changing environments, fungi need to be able to modify their physiology and in some cases will even modify their local environment. Understanding the interaction between fungi and their environments has been a topic of study for many decades. However, recently these studies have reached a new dimension. The availability of fungal genomes and development of post-genomic technologies for fungi, such as transcriptomics, proteomics and metabolomics, have enabled more detailed studies into this topic resulting in new insights. Based on a Special Interest Group session held during IMC9, this paper provides examples of the recent advances in using (post-)genomic approaches to better understand fungal interactions with their environments.

Duplications and losses in gene families of rust pathogens highlight putative effectors.

Science.gov (United States)

Pendleton, Amanda L; Smith, Katherine E; Feau, Nicolas; Martin, Francis M; Grigoriev, Igor V; Hamelin, Richard; Nelson, C Dana; Burleigh, J Gordon; Davis, John M

2014-01-01

Rust fungi are a group of fungal pathogens that cause some of the world's most destructive diseases of trees and crops. A shared characteristic among rust fungi is obligate biotrophy, the inability to complete a lifecycle without a host. This dependence on a host species likely affects patterns of gene expansion, contraction, and innovation within rust pathogen genomes. The establishment of disease by biotrophic pathogens is reliant upon effector proteins that are encoded in the fungal genome and secreted from the pathogen into the host's cell apoplast or within the cells. This study uses a comparative genomic approach to elucidate putative effectors and determine their evolutionary histories. We used OrthoMCL to identify nearly 20,000 gene families in proteomes of 16 diverse fungal species, which include 15 basidiomycetes and one ascomycete. We inferred patterns of duplication and loss for each gene family and identified families with distinctive patterns of expansion/contraction associated with the evolution of rust fungal genomes. To recognize potential contributors for the unique features of rust pathogens, we identified families harboring secreted proteins that: (i) arose or expanded in rust pathogens relative to other fungi, or (ii) contracted or were lost in rust fungal genomes. While the origin of rust fungi appears to be associated with considerable gene loss, there are many gene duplications associated with each sampled rust fungal genome. We also highlight two putative effector gene families that have expanded in Cqf that we hypothesize have roles in pathogenicity.

Airborne fungi in an intensive care unit

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C. L. Gonçalves

2017-07-01

Full Text Available Abstract The presence of airborne fungi in Intensive Care Unit (ICUs is associated with increased nosocomial infections. The aim of this study was the isolation and identification of airborne fungi presented in an ICU from the University Hospital of Pelotas – RS, with the attempt to know the place’s environmental microbiota. 40 Petri plates with Sabouraud Dextrose Agar were exposed to an environment of an ICU, where samples were collected in strategic places during morning and afternoon periods for ten days. Seven fungi genera were identified: Penicillium spp. (15.18%, genus with the higher frequency, followed by Aspergillus spp., Cladosporium spp., Fusarium spp., Paecelomyces spp., Curvularia spp., Alternaria spp., Zygomycetes and sterile mycelium. The most predominant fungi genus were Aspergillus spp. (13.92% in the morning and Cladosporium spp. (13.92% in the afternoon. Due to their involvement in different diseases, the identified fungi genera can be classified as potential pathogens of inpatients. These results reinforce the need of monitoring the environmental microorganisms with high frequency and efficiently in health institutions.

Population performance of collembolans feeding on soil fungi from different ecological niches

DEFF Research Database (Denmark)

Larsen, J.; Johansen, A.; Larsen, S.E.

2008-01-01

The potential reproductive value of arbuscular mycorrhizal fungi (Gloinus intraradices and Glomus invermaium), root pathogenic fungi (Rhizoctonia solani and Fusarium culmorum) and saprotrophic fungi (Penicillium hordei and Trichoderma harzianum) were examined for the collembolans Folsomia candida....... Different quality indicators such as the C:N ratio of the fungal food sources as well as other biological parameters are discussed in relation to their reproductive value and Collembola preferential feeding. (c) 2007 Elsevier Ltd. All rights reserved....

Pathogenic mycoflora on carrot seeds

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Bogdan Nowicki

2013-12-01

Full Text Available Altogether 300 seed samples were collected during 9 years in 8 regions of Poland and the fungi Were isolated and their pathogenicity to carrot seedlings was examined. Alternaria rudicina provcd to be the most important pathogen although. A. alternata was more common. The other important pathogens were Fusarium spp., Phoma spp. and Botrytis cinerea. The infection of carrot seeds by A. radicina should be used as an important criterium in seed quality evaluation.

Using hierarchical clustering of secreted protein families to classify and rank candidate effectors of rust fungi.

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Diane G O Saunders

Full Text Available Rust fungi are obligate biotrophic pathogens that cause considerable damage on crop plants. Puccinia graminis f. sp. tritici, the causal agent of wheat stem rust, and Melampsora larici-populina, the poplar leaf rust pathogen, have strong deleterious impacts on wheat and poplar wood production, respectively. Filamentous pathogens such as rust fungi secrete molecules called disease effectors that act as modulators of host cell physiology and can suppress or trigger host immunity. Current knowledge on effectors from other filamentous plant pathogens can be exploited for the characterisation of effectors in the genome of recently sequenced rust fungi. We designed a comprehensive in silico analysis pipeline to identify the putative effector repertoire from the genome of two plant pathogenic rust fungi. The pipeline is based on the observation that known effector proteins from filamentous pathogens have at least one of the following properties: (i contain a secretion signal, (ii are encoded by in planta induced genes, (iii have similarity to haustorial proteins, (iv are small and cysteine rich, (v contain a known effector motif or a nuclear localization signal, (vi are encoded by genes with long intergenic regions, (vii contain internal repeats, and (viii do not contain PFAM domains, except those associated with pathogenicity. We used Markov clustering and hierarchical clustering to classify protein families of rust pathogens and rank them according to their likelihood of being effectors. Using this approach, we identified eight families of candidate effectors that we consider of high value for functional characterization. This study revealed a diverse set of candidate effectors, including families of haustorial expressed secreted proteins and small cysteine-rich proteins. This comprehensive classification of candidate effectors from these devastating rust pathogens is an initial step towards probing plant germplasm for novel resistance components.

International Society of Human and Animal Mycology (ISHAM)-ITS reference DNA barcoding database--the quality controlled standard tool for routine identification of human and animal pathogenic fungi.

Science.gov (United States)

Irinyi, Laszlo; Serena, Carolina; Garcia-Hermoso, Dea; Arabatzis, Michael; Desnos-Ollivier, Marie; Vu, Duong; Cardinali, Gianluigi; Arthur, Ian; Normand, Anne-Cécile; Giraldo, Alejandra; da Cunha, Keith Cassia; Sandoval-Denis, Marcelo; Hendrickx, Marijke; Nishikaku, Angela Satie; de Azevedo Melo, Analy Salles; Merseguel, Karina Bellinghausen; Khan, Aziza; Parente Rocha, Juliana Alves; Sampaio, Paula; da Silva Briones, Marcelo Ribeiro; e Ferreira, Renata Carmona; de Medeiros Muniz, Mauro; Castañón-Olivares, Laura Rosio; Estrada-Barcenas, Daniel; Cassagne, Carole; Mary, Charles; Duan, Shu Yao; Kong, Fanrong; Sun, Annie Ying; Zeng, Xianyu; Zhao, Zuotao; Gantois, Nausicaa; Botterel, Françoise; Robbertse, Barbara; Schoch, Conrad; Gams, Walter; Ellis, David; Halliday, Catriona; Chen, Sharon; Sorrell, Tania C; Piarroux, Renaud; Colombo, Arnaldo L; Pais, Célia; de Hoog, Sybren; Zancopé-Oliveira, Rosely Maria; Taylor, Maria Lucia; Toriello, Conchita; de Almeida Soares, Célia Maria; Delhaes, Laurence; Stubbe, Dirk; Dromer, Françoise; Ranque, Stéphane; Guarro, Josep; Cano-Lira, Jose F; Robert, Vincent; Velegraki, Aristea; Meyer, Wieland

2015-05-01

Human and animal fungal pathogens are a growing threat worldwide leading to emerging infections and creating new risks for established ones. There is a growing need for a rapid and accurate identification of pathogens to enable early diagnosis and targeted antifungal therapy. Morphological and biochemical identification methods are time-consuming and require trained experts. Alternatively, molecular methods, such as DNA barcoding, a powerful and easy tool for rapid monophasic identification, offer a practical approach for species identification and less demanding in terms of taxonomical expertise. However, its wide-spread use is still limited by a lack of quality-controlled reference databases and the evolving recognition and definition of new fungal species/complexes. An international consortium of medical mycology laboratories was formed aiming to establish a quality controlled ITS database under the umbrella of the ISHAM working group on "DNA barcoding of human and animal pathogenic fungi." A new database, containing 2800 ITS sequences representing 421 fungal species, providing the medical community with a freely accessible tool at http://www.isham.org/ and http://its.mycologylab.org/ to rapidly and reliably identify most agents of mycoses, was established. The generated sequences included in the new database were used to evaluate the variation and overall utility of the ITS region for the identification of pathogenic fungi at intra-and interspecies level. The average intraspecies variation ranged from 0 to 2.25%. This highlighted selected pathogenic fungal species, such as the dermatophytes and emerging yeast, for which additional molecular methods/genetic markers are required for their reliable identification from clinical and veterinary specimens. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Comparative Genome Analysis of Basidiomycete Fungi

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Riley, Robert; Salamov, Asaf; Morin, Emmanuelle; Nagy, Laszlo; Manning, Gerard; Baker, Scott; Brown, Daren; Henrissat, Bernard; Levasseur, Anthony; Hibbett, David; Martin, Francis; Grigoriev, Igor

2012-03-19

Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes the mushrooms, wood rots, symbionts, and plant and animal pathogens. To better understand the diversity of phenotypes in basidiomycetes, we performed a comparative analysis of 35 basidiomycete fungi spanning the diversity of the phylum. Phylogenetic patterns of lignocellulose degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay. Patterns of secondary metabolic enzymes give additional insight into the broad array of phenotypes found in the basidiomycetes. We suggest that the profile of an organism in lignocellulose-targeting genes can be used to predict its nutritional mode, and predict Dacryopinax sp. as a brown rot; Botryobasidium botryosum and Jaapia argillacea as white rots.

The role of onion-associated fungi in bulb mite infestation and damage to onion seedlings.

Science.gov (United States)

Ofek, Tal; Gal, Shira; Inbar, Moshe; Lebiush-Mordechai, Sara; Tsror, Leah; Palevsky, Eric

2014-04-01

In Israel Rhizoglyphus robini is considered to be a pest in its own right, even though the mite is usually found in association with fungal pathogens. Plant protection recommendations are therefore to treat germinating onions seedlings, clearly a crucial phase in crop production, when mites are discovered. The aim of this study was to determine the role of fungi in bulb mite infestation and damage to germinating onion seedlings. Accordingly we (1) evaluated the effect of the mite on onion seedling germination and survival without fungi, (2) compared the attraction of the mite to species and isolates of various fungi, (3) assessed the effect of a relatively non-pathogenic isolate of Fusarium oxysporum on mite fecundity, and (4) determined the effects of the mite and of F. oxysporum separately and together, on onion seedling germination and sprout development. A significant reduction of seedling survival was recorded only in the 1,000 mites/pot treatment, after 4 weeks. Mites were attracted to 6 out of 7 collected fungi isolates. Mite fecundity on onion sprouts infested with F. oxysporum was higher than on non-infested sprouts. Survival of seedlings was affected by mites, fungi, and their combination. Sprouts on Petri dishes after 5 days were significantly longer in the control and mite treatments than both fungi treatments. During the 5-day experiment more mites were always found on the fungi-infected sprouts than on the non-infected sprouts. Future research using suppressive soils to suppress soil pathogens and subsequent mite damage is proposed.

[Isolation of endophytic fungi from medicinal plant Brucea javanica and their microbial inhibition activity].

Science.gov (United States)

Liang, Zi-Ning; Zhu, Hua; Lai, Kai-Ping; Chen, Long

2014-04-01

To isolate and identify endophytic fungi from Brucea javanica, and to detect the antimicrobial activity of these strains. Endophytic fungi were isolated by tissue inoculation culture and identified by conventional morphological characteristic method. Seven kinds of pathogenic fungi and three kinds of bacteria were used as targeting microbes to test microbial inhibition activities by agar plate antagonistic action and modified agar gel diffusion methods, respectively. A total of 83 endophytic fungi strains were isolated from the root, stem, leaf and fruit of Brucea javanica. 34 strains were obtained from the stem, 32 strains were obtained from the leaf, 15 strains were isolated from the root and 2 strains came from the fruit. These 73 strains which had been identified attribute to 5 orders, 6 families and 12 genera. For the isolated strains, 14 strains had antifungal activities against at least one pathogenic fungi, 9 strains showed antibacterial activities against one or more bacteria. Especially, the strain YJ-17 which belonged to Phomopsis genus showed the best inhibitory effect on the targeting microbes. The endophytic fungi from Brucea javanica show diversity and microbial inhibition activity, and are worthy for further study on plant disease controlling.

OCCURRENCE OF ENTOMOPATHOGENIC FUNGI IN SOILS FROM FESTUCA PRATENSIS HUDS. CROP

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Roman Kolczarek

2014-04-01

Full Text Available Entomopathogenic fungi are the largest group of microorganisms existing in the soil environment. Occurrence and pathogenicity of entomopathogenic fungi in soil is dependent on many factors affecting the soil environment. The aim of this study was to compare the species composition and the intensity of the occurrence of entomopathogenic fungi in soils from monoculture crops of Festuca pratensis Huds. The study material consisted of soil samples taken from the experiment conducted in two experimental stations of the Research Centre for Cultivars Study. The insecticides fungi were isolated from soil using a method of the selective substrate. Three species of entomopathogenic fungi Beauveria bassiana, Isaria fumosorosea and Metarhizium anisopliae were isolated from the study soils using the selective medium.

Identification of a new biocontrol gene in Trichoderma atroviride: the role of an ABC transporter membrane pump in the interaction with different plant-pathogenic fungi.

Science.gov (United States)

Ruocco, Michelina; Lanzuise, Stefania; Vinale, Francesco; Marra, Roberta; Turrà, David; Woo, Sheridan Lois; Lorito, Matteo

2009-03-01

Successful biocontrol interactions often require that the beneficial microbes involved are resistant or tolerant to a variety of toxicants, including antibiotics produced by themselves or phytopathogens, plant antimicrobial compounds, and synthetic chemicals or contaminants. The ability of Trichoderma spp., the most widely applied biocontrol fungi, to withstand different chemical stresses, including those associated with mycoparasitism, is well known. In this work, we identified an ATP-binding cassette transporter cell membrane pump as an important component of the above indicated resistance mechanisms that appears to be supported by an extensive and powerful cell detoxification system. The encoding gene, named Taabc2, was cloned from a strain of Trichoderma atroviride and characterized. Its expression was found to be upregulated in the presence of pathogen-secreted metabolites, specific mycotoxins and some fungicides, and in conditions that stimulate the production in Trichoderma spp. of antagonism-related factors (toxins and enzymes). The key role of this gene in antagonism and biocontrol was demonstrated by the characterization of the obtained deletion mutants. They suffered an increased susceptibility to inhibitory compounds either secreted by pathogenic fungi or possibly produced by the biocontrol microbe itself and lost, partially or entirely, the ability to protect tomato plants from Pythium ultimum and Rhizoctonia solani attack.

Duplications and losses in gene families of rust pathogens highlight putative effectors

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Amanda L. Pendleton

2014-06-01

Full Text Available Rust fungi are a group of fungal pathogens that cause some of the world’s most destructive diseases of trees and crops. A shared characteristic among rust fungi is obligate biotrophy, the inability to complete a lifecycle without a host. This dependence on a host species likely affects patterns of gene expansion, contraction, and innovation within rust pathogen genomes. The establishment of disease by biotrophic pathogens is reliant upon effector proteins that are encoded in the fungal genome and secreted from the pathogen into the host’s cell apoplast or within the cells. This study uses a comparative genomic approach to elucidate putative effectors and determine their evolutionary histories. We used OrthoMCL to identify nearly 20,000 gene families in proteomes of sixteen diverse fungal species, which include fifteen basidiomycetes and one ascomycete. We inferred patterns of duplication and loss for each gene family and identified families with distinctive patterns of expansion/contraction associated with the evolution of rust fungal genomes. To recognize potential contributors for the unique features of rust pathogens, we identified families harboring secreted proteins that: i arose or expanded in rust pathogens relative to other fungi, or ii contracted or were lost in rust fungal genomes. While the origin of rust fungi appears to be associated with considerable gene loss, there are many gene duplications associated with each sampled rust fungal genome. We also highlight two putative effector gene families that have expanded in Cqf that we hypothesize have roles in pathogenicity.

The Use of Rock Phosphate and Phosphate Solubilising Fungi ...

African Journals Online (AJOL)

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produces citric and oxalic acids to solubilize calcium ... acid). Available phosphorus was determined using the method of Bray & Kurtz (1945). ..... Oxalate production by fungi: its role in pathogenicity and ecology in the soil environment.

Analysis of the Pathogenic Factors and Management of Dry Eye in Ocular Surface Disorders.

Science.gov (United States)

Nebbioso, Marcella; Del Regno, Paola; Gharbiya, Magda; Sacchetti, Marta; Plateroti, Rocco; Lambiase, Alessandro

2017-08-13

The tear film represents the interface between the eye and the environment. The alteration of the delicate balance that regulates the secretion and distribution of the tear film determines the dry eye (DE) syndrome. Despite having a multifactorial origin, the main risk factors are female gender and advanced age. Likewise, morphological changes in several glands and in the chemical composition of their secretions, such as proteins, mucins, lipidics, aqueous tears, and salinity, are highly relevant factors that maintain a steady ocular surface. Another key factor of recurrence and onset of the disease is the presence of local and/or systemic inflammation that involves the ocular surface. DE syndrome is one of the most commonly encountered diseases in clinical practice, and many other causes related to daily life and the increase in average life expectancy will contribute to its onset. This review will consider the disorders of the ocular surface that give rise to such a widespread pathology. At the end, the most recent therapeutic options for the management of DE will be briefly discussed according to the specific underlying pathology.

The fungi causin damping-off of carrot seedlings

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Bogdan Nowicki

2013-12-01

Full Text Available When 136 samples of dying carrot seedlings from several fields were analyzed Alternaria rudicina proved to be the most common seedling pathogen (41%, followed by some Fusarium species (27%, mostly F. avenaceum.The less common seedling pathogens were Pythium spp. (13%, Phoma spp.(2,5% and Botrytis cinerea (1,4%. Some other fungi (Bipolaris sorokiniana, Sclerotinia sclerotiorum, Stemphylium botryosym and Ulocladium consortiale were found in less than 1% of seedlings examined.

Virulence of entomopathogenic hypocrealean fungi infecting Anoplophora glabripennis

Science.gov (United States)

Thomas Dubois; Jennifer Lund; Leah S. Bauer; Ann E. Hajek

2008-01-01

Twenty isolates of four species of entomopathogenic hypocrealean fungi (Beauveria bassiana, Beauveria brongniartii, Isaria farinosa, and Metarhizium anisopliae) were found to be pathogenic to adults of the Asian longhorned beetle, Anoplophora glabripennis. Survival times for 50% of the beetles tested (ST

Occurrence of root parsley pathogens inhabiting seeds

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Bogdan Nowicki

2013-12-01

Full Text Available The studies on root parsley pathogens inhabiting seeds were conducted during 1981-1988 and in 1993. Filter paper method with prefreezing and keeping under light was used. Each test sample comprised 500 seeds. Pathogenicity of collected fungal isolates was tested following two laboratory methods. 238 seed samples were studied. 18 fungal species were found but only 7 proved to be important pathogens of root parsley. The most common inhabitants of root parsley seeds were Alternaria spp. A.allernata occurred on 74,8% of seeds but only a few isolates showed to be slightly pathogenic while A.petroselini and A.radicina were higly pathogenic and inhabited 11,4 and 4,2% of seeds, respectively. The second group of important pathogens were species of Fusarium found on 3,9% of seeds. F.avenaceum dominated as it comprised 48% of Fusarium isolates, the next were as follow: F.culmorum - 20%, F.equiseti - 15%, F.solani - 8%, F.oxysporum - 7% and F.dimerum -2%. Some fungi like Botrytis cinerea, Septoria petroselini and Phoma spp. inhabited low number of seeds, respectively O,4; 0,5 and 0,8%, but they were highly pathogenic to root parsley. The fungi: Bipolaris sorokiniana, Drechslera biseptata, Stemphylium botryosum and Ulocludium consortiale showed slight pathogenicity. They were isolated from 3,8% of seeds.

A reassessment of the risk of rust fungi developing resistance to fungicides.

Science.gov (United States)

Oliver, Richard P

2014-11-01

Rust fungi are major pathogens of many annual and perennial crops. Crop protection is largely based on genetic and chemical control. Fungicide resistance is a significant issue that has affected many crop pathogens. Some pathogens have rapidly developed resistance and hence are regarded as high-risk species. Rust fungi have been classified as being low risk, in spite of sharing many relevant features with high-risk pathogens. An examination of the evidence suggests that rust fungi may be wrongly classified as low risk. Of the nine classes of fungicide to which resistance has developed, six are inactive against rusts. The three remaining classes are quinone outside inhibitors (QoIs), demethylation inhibitors (DMIs) and succinate dehydrogenase inhibitors (SDHIs). QoIs have been protected by a recently discovered intron that renders resistant mutants unviable. Low levels of resistance have developed to DMIs, but with limited field significance. Older SDHI fungicides were inactive against rusts. Some of the SDHIs introduced since 2003 are active against rusts, so it may be that insufficient time has elapsed for resistance to develop, especially as SDHIs are generally sold in mixtures with other actives. It would therefore seem prudent to increase the level of vigilance for possible cases of resistance to established and new fungicides in rusts. © 2014 Society of Chemical Industry.

Swainsonine biosynthesis genes in diverse symbiotic and pathogenic fungi

Science.gov (United States)

Swainsonine, a cytotoxic fungal alkaloid and a potential cancer therapy drug, is produced by the insect pathogen and plant symbiont, Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glo...

The genomic organization of plant pathogenicity in Fusarium species

NARCIS (Netherlands)

Rep, M.; Kistler, H.C.

2010-01-01

Comparative genomics is a powerful tool to infer the molecular basis of fungal pathogenicity and its evolution by identifying differences in gene content and genomic organization between fungi with different hosts or modes of infection. Through comparative analysis, pathogenicity-related chromosomes

The effects of chloramphenicol and 60Co irradiation on the experimental mycosis in mice inoculated intragastrically with two kinds of pathogenic yeast-like fungi

International Nuclear Information System (INIS)

Kitamura, Isamu

1975-01-01

Two kinds of pathogenic yeast, Cryptococcus neoformans and Candida albicans were inoculated into the stomachs of mice. The effects of intragastric administration of chloramphenicol (CM) and systemic irradiation with 60 Co on the acceralation of infection were studied in intragastrically inoculated mice. When Cryptococcus neoformans were simply inoculated, it was difficult for them to reside in the alimentary canal to cause infection. In case of candida albicans inoculated simply, they were also unable to induce infection though they remained in the alimentary canal for a long time. In the experiment combining intragastric administration of the fungi and CM some mice contracted the disease and died. The effect of CM in causing infection was not proved. In the experiments combining 60 Co irradiation and intragastric administration of CM and fungi, a high incidence of fungus infection was noted with both Cryptococcus neoformans and Candida albicans. Fungus lesions were observed in many organs, and in all of the mice which died systemic fungus lesions were noted. It was shown that systemic irradiation with 60 Co had a specific effect on facilitating the infection. In these studies no difference was observed in the incidence of the fungus disease in respect of the origin of the causative fungi. (J.P.N.)

Search of yeast-like fungi in some lakes of the Tucholski Landscape Park (NW Poland

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Anna Rózga

2014-08-01

Full Text Available The occurrence of pathogenic yeast-like fungi was determined in the catchment of the Suska and Raciąska Struga. Fourteen strains of fungi from 3 genera were isolated: Candida inconspicua, C. lambica, C. glabrata, Rhodotorula rubra, Rh. glutinls and Trichosporon capitatum.

Storage rot fungi and seed-borne pathogens of onion | Adongo ...

African Journals Online (AJOL)

Rotten onion bulbs obtained from the four markets (Abinchi, Anloga, Kwadaso and Central markets) were infected by five fungal species: Aspergillus niger, A. flavus, Penicillium sp., Rhizopus stolonifer and Fusarium oxysporum. Of these, A. niger and Penicillium sp. were the most frequently isolated fungi. A. flavus was the ...

The impact of the postharvest environment on the viability and virulence of decay fungi.

Science.gov (United States)

Liu, Jia; Sui, Yuan; Wisniewski, Michael; Xie, Zhigang; Liu, Yiqing; You, Yuming; Zhang, Xiaojing; Sun, Zhiqiang; Li, Wenhua; Li, Yan; Wang, Qi

2018-07-03

Postharvest decay of fruits, vegetables, and grains by fungal pathogens causes significant economic losses. Infected produce presents a potential health risk since some decay fungi produce mycotoxins that are hazardous to human health. Infections are the result of the interplay between host resistance and pathogen virulence. Both of these processes, however, are significantly impacted by environmental factors, such as temperature, UV, oxidative stress, and water activity. In the present review, the impact of various physical postharvest treatments (e.g., heat and UV) on the viability and virulence of postharvest pathogens is reviewed and discussed. Oxidative injury, protein impairment, and cell wall degradation have all been proposed as the mechanisms by which these abiotic stresses reduce fungal viability and pathogenicity. The response of decay fungi to pH and the ability of pathogens to modulate the pH of the host environment also affect pathogenicity. The effects of the manipulation of the postharvest environment by ethylene, natural edible coatings, and controlled atmosphere storage on fungal viability are also discussed. Lastly, avenues of future research are proposed.

Action on the Surface: Entomopathogenic Fungi versus the Insect Cuticle.

Science.gov (United States)

Ortiz-Urquiza, Almudena; Keyhani, Nemat O

2013-07-16

Infections mediated by broad host range entomopathogenic fungi represent seminal observations that led to one of the first germ theories of disease and are a classic example of a co-evolutionary arms race between a pathogen and target hosts. These fungi are able to parasitize susceptible hosts via direct penetration of the cuticle with the initial and potentially determining interaction occurring between the fungal spore and the insect epicuticle. Entomogenous fungi have evolved mechanisms for adhesion and recognition of host surface cues that help direct an adaptive response that includes the production of: (a) hydrolytic, assimilatory, and/or detoxifying enzymes including lipase/esterases, catalases, cytochrome P450s, proteases, and chitinases; (b) specialized infectious structures, e.g., appressoria or penetrant tubes; and (c) secondary and other metabolites that facilitate infection. Aside from immune responses, insects have evolved a number of mechanisms to keep pathogens at bay that include: (a) the production of (epi) cuticular antimicrobial lipids, proteins, and metabolites; (b) shedding of the cuticle during development; and (c) behavioral-environmental adaptations such as induced fever, burrowing, and grooming, as well as potentially enlisting the help of other microbes, all intended to stop the pathogen before it can breach the cuticle. Virulence and host-defense can be considered to be under constant reciprocal selective pressure, and the action on the surface likely contributes to phenomena such as strain variation, host range, and the increased virulence often noted once a (low) virulent strain is "passaged" through an insect host. Since the cuticle represents the first point of contact and barrier between the fungus and the insect, the "action on the surface" may represent the defining interactions that ultimately can lead either to successful mycosis by the pathogen or successful defense by the host. Knowledge concerning the molecular mechanisms

Yeast-like fungi possessing bio-indicator properties isolated from the Łyna river

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Maria Dynowska

2014-08-01

Full Text Available Yeast-like fungi isolated in the Łyna river are constant components of microflora of inland waters. Every increase in their number indicates progress in the process of eutrophication and accumulation of organic and inorganic pollutans. The fungi Candida aibicans, Pichia guilliermondii, P. anomala, Rhodotorula glutinis i Trichosporon beigelii, potentially pathogenic apperred in water with high content of municipal sewage, but T. aquatile - in the clean waters only. The tested fungi can be also considered as bio-indicators.

The effect of mineral fertilization on fungi colonizing potato (Solanum tuberosum L. tubers after harvest and after storage

Directory of Open Access Journals (Sweden)

Bożena Cwalina-Ambroziak

2012-12-01

Full Text Available The paper presents the results of a three-year exact experiment conducted in Bałcyny, in which a late potato cultivar, Jasia, was grown. The objective of the study was to determine the effect of different levels of mineral fertilization: A (N 80 kg × ha-1 P 80 kg × ha-1 K120 kg × ha-1 and B (N 120 kg × ha-1 P 144 kg × ha-1 K156 kg × ha-1, and foliar fertilization (Basfoliar 12-4-6, ADOB Mn and Solubor DF on the quantitative and qualitative composition of fungal populations colonizing potato tubers. Fungi were isolated immediately after harvest and after a five-month storage period. After seven days of incubation, fungal colonies were transferred onto agar slants for microscopic identification. Over the entire experimental period, more pathogenic fungi were obtained from potato tubers analyzed after storage (62.9% of the total fungal population after storage than from those analyzed immediately after harvest (39.1%, and the greatest number of fungi was reported in 2004. Rhizoctonia solani was isolated most frequently, followed by Colletotrichum coccodes and Alternaria alternata. Pathogens of the genus Fusarium and the species Helminthosporium solani were not numerous. In the treatment A with soil mineral fertilization with lower NPK rates, larger numbers of pathogenic fungi were noted in 2004 after harvest and after five-month storage, and in 2005 after harvest. At the remaining dates of analysis, pathogens were more frequently isolated from potato tubers in experimental variant B with higher NPK rates. Immediately after harvest, the highest number of pathogenic fungi was isolated in the treatment with foliar application of ADOB Mn and Basfoliar 12-4-6. After five-month storage, pathogens most often colonized potato tubers in experimental variant B with foliar application of Solubor DF, Solubor DF and ADOB Mn, and in experimental variant A with a combination of fertilizers. In the other fertilization variants, including in the control

Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil.

Science.gov (United States)

Oliveira, Helena M B; Santos, Cledir; Paterson, R Russell M; Gusmão, Norma B; Lima, Nelson

2016-03-09

Filamentous fungi in drinking water distribution systems are known to (a) block water pipes; (b) cause organoleptic biodeterioration; (c) act as pathogens or allergens and (d) cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife-Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU)/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively), followed by Trichoderma and Fusarium (9% each), Curvularia (5%) and finally the species Pestalotiopsis karstenii (2%). Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens.

Pathogen avoidance by insect predators

OpenAIRE

Meyling, Nicolai V.; Ormond, Emma; Roy, Helen E.; Pell, Judith K.

2008-01-01

Insects can detect cues related to the risk of attack by their natural enemies. Pathogens are among the natural enemies of insects and entomopathogenic fungi attack a wide array of host species. Evidence documents that social insects in particular have adapted behavioural mechanisms to avoid infection by fungal pathogens. These mechanisms are referred to as 'behavioural resistance'. However, there is little evidence for similar adaptations in non-social insects. We have conducted experime...

Succession of root-associated fungi in Pisum sativum during a plant growth cycle as examined by 454 pyrosequencing

DEFF Research Database (Denmark)

Yu, L.; Nicolaisen, M.; Larsen, J.

2012-01-01

Purpose Roots are inhabited by a broad range of fungi, including pathogens and mycorrhizal fungi, with functional traits related to plant health and nutrition. Management of these fungi in agroecosystems requires profound knowledge about their ecology. The main objective of this study was to exam...

Cercosporoid fungi (Mycosphaerellaceae) 2. Species on monocots (Acoraceae to Xyridaceae, excluding Poaceae)

OpenAIRE

Braun, Uwe; Crous, Pedro W.; Nakashima, Chiharu

2014-01-01

Cercosporoid fungi (formerly Cercospora s. lat.) represent one of the largest groups of hyphomycetes belonging to the Mycosphaerellaceae (Ascomycota). They include asexual morphs, asexual holomorphs, or species with mycosphaerella-like sexual morphs. Most of them are leaf-spotting plant pathogens with special phytopathological relevance. In the first part of a new monographic work, cercosporoid hyphomycetes occurring on other fungi (fungicolous species), on ferns (pteridophytes) and gymnosper...

Networks Depicting the Fine-Scale Co-Occurrences of Fungi in Soil Horizons.

Science.gov (United States)

Toju, Hirokazu; Kishida, Osamu; Katayama, Noboru; Takagi, Kentaro

2016-01-01

Fungi in soil play pivotal roles in nutrient cycling, pest controls, and plant community succession in terrestrial ecosystems. Despite the ecosystem functions provided by soil fungi, our knowledge of the assembly processes of belowground fungi has been limited. In particular, we still have limited knowledge of how diverse functional groups of fungi interact with each other in facilitative and competitive ways in soil. Based on the high-throughput sequencing data of fungi in a cool-temperate forest in northern Japan, we analyzed how taxonomically and functionally diverse fungi showed correlated fine-scale distributions in soil. By uncovering pairs of fungi that frequently co-occurred in the same soil samples, networks depicting fine-scale co-occurrences of fungi were inferred at the O (organic matter) and A (surface soil) horizons. The results then led to the working hypothesis that mycorrhizal, endophytic, saprotrophic, and pathogenic fungi could form compartmentalized (modular) networks of facilitative, antagonistic, and/or competitive interactions in belowground ecosystems. Overall, this study provides a research basis for further understanding how interspecific interactions, along with sharing of niches among fungi, drive the dynamics of poorly explored biospheres in soil.

Response of root fungi in Pisum sativum to plant and soil environmental factors

DEFF Research Database (Denmark)

Yu, Lingling

and nutritional status of the plant and soil environments. However, limited information is available about the richness and composition of most of these root-associated fungi as studies of fungal communities remain a challenge because of below-ground high taxonomic and ecological diversity. In the present study......; thus obligate biotrophic fungi and saprotrophic fungi were markedly increased with organic fertilizer dosages, while root pathogenic fungi were decreased with organic amendments. In conclusion, the present work has shown that root-associated fungal community structure relate to plant and soil...... environmental factors. The obtained knowledge from this study can provide novel information of communities of root-associated fungi; thus improving the basic understanding of plant-root fungi-environment interactions in agroecosystems....

In situ hybridization for the detection of rust fungi in paraffin embedded plant tissue sections

Science.gov (United States)

Rust fungi infect a wide range of plant species making them of particular interest to plant pathologists. In order to study the interactions between these important pathogenic fungi and their host plants it is useful to be able to differentiate fungal tissue from plant tissue. This can be accomplish...

Antimicrobial role of human meibomian lipids at the ocular surface.

Science.gov (United States)

Mudgil, Poonam

2014-10-14

Human meibomian lipids form the outermost lipid layer of the tear film and serve many important functions to maintain its integrity. Although not investigated earlier, these lipids may have antimicrobial properties that help in strengthening the innate host defense of tears at the ocular surface. The aim of this study was to investigate the antimicrobial role of human meibomian lipids. Ocular pathogenic bacteria, Staphylococcus aureus 31, Pseudomonas aeruginosa 19, Pseudomonas aeruginosa 20, and Serratia marcescens 35, were grown in the presence and absence of human meibomian lipids in an artificial tear solution at the physiological temperature. Viable counts were obtained to note the number of bacteria surviving the treatment with meibomian lipids. Bacterial cells were imaged using scanning electron microscopy to observe the damages caused by meibomian lipids. Viable count results showed that in the presence of meibomian lipids, growth of all bacteria was considerably lower. Scanning electron microscopy showed that meibomian lipids caused extensive cellular damage to bacteria as manifested in smaller size, loss of aggregation, abnormal phenotype, cellular distortion, damaged cell wall, and cell lysis. This is the first-ever report of the antimicrobial role of human meibomian lipids. These lipids possess antimicrobial properties against both Gram-positive and Gram-negative bacteria and are involved in the innate host defense of tears in protecting the ocular surface against microbial pathogens. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Correlation of Soil Environmental to Diversity the Entomopathogenic Fungi

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Rose Novita Sari Handoko

2017-01-01

Full Text Available Ecosystem rice fields that have high diversity, able to control the pest. Habitat entomopathogenic fungi in the soil have been examined on cabbage plants but has not been reported in the rice field. The study was conducted through surveys of crops and paddy fields by the application of IPM in Kasembon Malang. A total of 5 points soil samples were determined diagonally used in this study. Isolation of entomopathogenic fungi from the rhizosphere of paddy is done by plate dilution method. Entomopathogenic fungi were identified to genus level by observing the macroscopic and microscopic characteristics. Koch's postulates done on Tenebrio molitor, then observe the symptoms and mortality of Spodoptera litura time pathogenicity test. The results showed that the genus of entomopathogenic fungi in the rhizosphere of rice is Penicillium sp., Aspergillus sp. and has not been identified. Chemical analysis of soil for pH is 4.00 to 5.00. Soil organic matter is 1.89% to 3.20%.   Keywords: diversity, entomopathogenic fungi, integrated pest management, rhizosphere

OCULAR ASPECTS OF HYPERTHYROIDISM WITH SPECIAL REFERENCE TO OCULAR MYOPATHY

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Mallika O. U

2017-04-01

Full Text Available BACKGROUND Hyperthyroidism can result in ocular manifestations even before systemic signs and symptoms develop. It is seen more in females and severe forms are more common in males. Early detection of ocular involvement can prevent vision threatening complications and troublesome discomforts affecting quality of vision. This clinical study highlights the importance of detailed ocular examination in hyperthyroidism. MATERIALS AND METHODS Fifty consecutive patients with ocular signs of hyperthyroidism were evaluated and followed up for an average period of 1 year. Detailed ocular examination included exophthalmometric measurements, ocular movements and Worth four-dot test. T3, T4, TSH, CT scan and antimicrosomal antibodies and antithyroglobulin antibodies were done along with routine investigations. Study Design- Prospective cohort study. RESULTS Statistical analysis did not reveal any correlation between the level of serum T3 and severity of ocular findings. Majority of the cases were euthyroid with moderate ocular myopathy having multiple muscle involvement. Inferior rectus was affected most. CONCLUSION The ocular signs of hyperthyroidism in the present study seem to be mild. The severe eye changes like corneal involvement and optic nerve changes were less common.

[Keratinophilic fungi in soils of parks of Corrientes city, Argentina].

Science.gov (United States)

Sarmiento, María Mercedes; Mangiaterra, Magdalena; Bojanich, María Viviana; Basualdo, Juan Ángel; Giusiano, Gustavo

2016-01-01

The soil is a natural reservoir of keratinophilic fungi, which are a small but important group of filamentous fungi, some of which typically develop on keratinized tissues of living animals. There are numerous species of saprophytic fungi with recognized keratinophilic abilities, and several studies have been undertaken in order to link their presence to possible human disease. To know the biota of geophilic fungi in general and of keratinophilic fungi particularly in soils from two public parks. Soil samples from two public parks of Corrientes city, Argentina, were studied during two seasons, using the hook technique and serial dilutions for fungal isolation. Using the hook technique, 170 isolates were classified into 17 genera and 21 species, among which it is worth mentioning the presence of Microsporum canis. Shannon index for keratinophilic fungi in autumn was 2.27, and 1.92 in spring. By means of the serial dilutions technique, 278 fungi isolated were identified into 33 genera and 71 species. Shannon index in autumn was 3.9, and 3.5 in spring. The soils studied have particularly favorable conditions for the survival of pathogens and opportunistic geophilic fungi for humans and animals. Copyright © 2014 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

Calcineurin orchestrates dimorphic transitions, antifungal drug responses and host-pathogen interactions of the pathogenic mucoralean fungus Mucor circinelloides.

Science.gov (United States)

Lee, Soo Chan; Li, Alicia; Calo, Silvia; Inoue, Makoto; Tonthat, Nam K; Bain, Judith M; Louw, Johanna; Shinohara, Mari L; Erwig, Lars P; Schumacher, Maria A; Ko, Dennis C; Heitman, Joseph

2015-09-01

Calcineurin plays essential roles in virulence and growth of pathogenic fungi and is a target of the natural products FK506 and Cyclosporine A. In the pathogenic mucoralean fungus Mucor circinelloides, calcineurin mutation or inhibition confers a yeast-locked phenotype indicating that calcineurin governs the dimorphic transition. Genetic analysis in this study reveals that two calcineurin A catalytic subunits (out of three) are functionally diverged. Homology modeling illustrates modes of resistance resulting from amino substitutions in the interface between each calcineurin subunit and the inhibitory drugs. In addition, we show how the dimorphic transition orchestrated by calcineurin programs different outcomes during host-pathogen interactions. For example, when macrophages phagocytose Mucor yeast, subsequent phagosomal maturation occurs, indicating host cells respond appropriately to control the pathogen. On the other hand, upon phagocytosis of spores, macrophages fail to form mature phagosomes. Cytokine production from immune cells differs following exposure to yeast versus spores (which germinate into hyphae). Thus, the morphogenic transition can be targeted as an efficient treatment option against Mucor infection. In addition, genetic analysis (including gene disruption and mutational studies) further strengthens the understanding of calcineurin and provides a foundation to develop antifungal agents targeting calcineurin to deploy against Mucor and other pathogenic fungi. © 2015 John Wiley & Sons Ltd.

Organic fertilization alters the community composition of root associated fungi in Pisum sativum

DEFF Research Database (Denmark)

Yu, L.; Nicolaisen, M.; Ravnskov, S.

2013-01-01

Organic fertilization is well known to affect individual functional groups of root associated fungi such as arbuscular mycorrhizal (AM) fungi and root pathogens, but limited information is available on the effect of organic fertilization at the fungal community composition level. The main objective...... of the present study was to examine the response of communities of root associated fungi in Pisum sativum to Protamylasse, an organic fertilizer used in pea production. Plants were grown in pots with field soil amended with four different levels of Protamylasse. 454 pyrosequencing was employed to examine......, the organic fertilizer Protamylasse clearly affects communities of root associated fungi, which seems to be linked to the life strategy of the different functional groups of root associated fungi. --------------------------------------------------------------------------------...

Ocular pharmacokinetics of besifloxacin following topical administration to rabbits, monkeys, and humans.

Science.gov (United States)

Proksch, Joel W; Granvil, Camille P; Siou-Mermet, Raphaële; Comstock, Timothy L; Paterno, Michael R; Ward, Keith W

2009-08-01

Studies were conducted to evaluate the ocular penetration and systemic exposure to besifloxacin, a fluoroquinolone antibiotic, following topical ocular administration to animals and humans. Besifloxacin ophthalmic suspension (0.6%) was administered as a topical ocular instillation to pigmented rabbits, cynomolgus monkeys, and human subjects. At predetermined intervals after dosing, samples of ocular tissues and plasma were collected and analyzed for besifloxacin levels using HPLC/MS/MS methods. Besifloxacin demonstrated good ocular penetration in rabbits and monkeys, with rapid absorption and sustained concentrations observed in anterior ocular tissues through 24 h after a single administration. Maximum besifloxacin concentrations in conjunctiva, cornea, and aqueous humor of monkeys were 6.43 microg/g, 2.10 microg/g, and 0.796 microg/mL, respectively, after a single topical dose, and concentrations declined in these tissues with an apparent half-life of 5-14 h. Following a single topical ocular administration to humans, the maximum besifloxacin concentration in tears was 610 microg/g with concentrations decreasing to approximately 1.6 microg/g at 24 h. The resulting pharmacokinetic parameters for besifloxacin in human tears were evaluated relative to the MIC(90) values (microg/mL) for besifloxacin against Streptococcus pneumoniae (0.125), Staphylococcus aureus (0.25), Staphylococcus epidermidis (0.5), and Haemophilus influenzae (0.06). Following a single topical administration, the C(max)/MIC(90) ratios for besifloxacin in human tears were > or =1,220, and the AUC((0-24))/MIC(90) ratios were > or =2,500 for these relevant ocular pathogens. Following repeated 3-times daily (TID) topical ocular administration to human subjects with clinically diagnosed bacterial conjunctivitis, maximum besifloxacin concentrations in plasma were less than 0.5 ng/mL, on average. Taken together, the results of the current investigation provide a PK/PD-based rationale that supports the

Sequencing the Major Mycosphaerella Pathogens of Wheat and Banana

NARCIS (Netherlands)

Kema, G.H.J.

2009-01-01

Mycosphaerella is one of the largest genera of plant-pathogenic fungi with more than 1,000 named species, many of which are important pathogens causing leaf spotting diseases in a wide variety of crops including cereals, citrus, banana, eucalypts, soft fruits and horticultural crops. A few species

Sequencing the Major Mycosphaerella Pathogens of Wheat and Banana

NARCIS (Netherlands)

Kema, G.H.; Dunkle, L.D.; Churchill, A.C.; Carlier, J.; James, A.; Souza, M.T.; Crous, P.W.; Roux, N.; Lee, T.A. van der; Wiitenberg, A.; Lindquist, E.; Grigoriev, I.; Bristow, J.; Goodwin, S.B.

2007-01-01

Mycosphaerella is one of the largest genera of plant pathogenic fungi with more than 1,000 named species, many of which are important pathogens causing leaf spotting diseases in a wide variety of crops including cereals, citrus, banana, eucalypts, soft fruits, and horticultural crops. A few species

Genomic DNA extraction and barcoding of endophytic fungi.

Science.gov (United States)

Diaz, Patricia L; Hennell, James R; Sucher, Nikolaus J

2012-01-01

Endophytes live inter- and/or intracellularly inside healthy aboveground tissues of plants without causing disease. Endophytic fungi are found in virtually every vascular plant species examined. The origins of this symbiotic relationship between endophytes go back to the emergence of vascular plants. Endophytic fungi receive nutrition and protection from their hosts while the plants benefit from the production of fungal secondary metabolites, which enhance the host plants' resistance to herbivores, pathogens, and various abiotic stresses. Endophytic fungi have attracted increased interest as potential sources of secondary metabolites with agricultural, industrial, and medicinal use. This chapter provides detailed protocols for isolation of genomic DNA from fungal endophytes and its use in polymerase chain reaction-based amplification of the internal transcribed spacer region between the conserved flanking regions of the small and large subunit of ribosomal RNA for barcoding purposes.

Dung-inhabiting fungi: a potential reservoir of novel secondary metabolites for the control of plant pathogens.

Science.gov (United States)

Sarrocco, Sabrina

2016-04-01

Coprophilous fungi are a large group of saprotrophic fungi mostly found in herbivore dung. The number of these fungi undergoing investigation is continually increasing, and new species and genera continue to be described. Dung-inhabiting fungi play an important ecological role in decomposing and recycling nutrients from animal dung. They produce a large array of bioactive secondary metabolites and have a potent enzymatic arsenal able to utilise even complex molecules. Bioactive secondary metabolites are actively involved in interaction with and defence against other organisms whose growth can be inhibited, resulting in an enhanced ecological fitness of producer strains. Currently, these antibiotics and bioactive secondary metabolites are of interest in medicine in particular, while very little information is available concerning their potential use in agriculture. This review introduces the ecology of dung-inhabiting fungi, with particular emphasis on the production of antibiotic compounds as a means to compete with other microorganisms. Owing to the fast pace of technological progress, new approaches to predicting the biosynthesis of bioactive metabolites are proposed. Coprophilous fungi should be considered as elite candidate organisms for the discovery of novel antifungal compounds, above all in view of their exploitation for crop protection. © 2015 Society of Chemical Industry.

Comparative genome analysis of Basidiomycete fungi

Energy Technology Data Exchange (ETDEWEB)

Riley, Robert; Salamov, Asaf; Henrissat, Bernard; Nagy, Laszlo; Brown, Daren; Held, Benjamin; Baker, Scott; Blanchette, Robert; Boussau, Bastien; Doty, Sharon L.; Fagnan, Kirsten; Floudas, Dimitris; Levasseur, Anthony; Manning, Gerard; Martin, Francis; Morin, Emmanuelle; Otillar, Robert; Pisabarro, Antonio; Walton, Jonathan; Wolfe, Ken; Hibbett, David; Grigoriev, Igor

2013-08-07

Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprotrophs including the majority of wood decaying and ectomycorrhizal species. To better understand the genetic diversity of this phylum we compared the genomes of 35 basidiomycetes including 6 newly sequenced genomes. These genomes span extremes of genome size, gene number, and repeat content. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) found in only one organism. Correlations between lifestyle and certain gene families are evident. Phylogenetic patterns of plant biomass-degrading genes in Agaricomycotina suggest a continuum rather than a dichotomy between the white rot and brown rot modes of wood decay. Based on phylogenetically-informed PCA analysis of wood decay genes, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has typical ligninolytic class II fungal peroxidases (PODs). This prediction is supported by growth assays in which both fungi exhibit wood decay with white rot-like characteristics. Based on this, we suggest that the white/brown rot dichotomy may be inadequate to describe the full range of wood decaying fungi. Analysis of the rate of discovery of proteins with no or few homologs suggests the value of continued sequencing of basidiomycete fungi.

Massive gene swamping among cheese-making Penicillium fungi

Directory of Open Access Journals (Sweden)

Jeanne Ropars

2015-03-01

Full Text Available Horizontal gene transfers (HGT, i.e., the transmission of genetic material between species not directly attributable to meiotic gene exchange, have long been acknowledged as a major driver of prokaryotic evolution and is increasingly recognized as an important source of adaptation in eukaryotes. In fungi in particular, many convincing examples of HGT have been reported to confer selective advantages on the recipient fungal host, either promoting fungal pathogenicity on plants or increasing their toxicity by the acquisition of secondary metabolic clusters, resulting in adaptation to new niches and in some cases eventually even in speciation. These horizontal gene transfers involve single genes, complete metabolic pathways or even entire chromosomes. A recent study has uncovered multiple recent horizontal transfers of a 575 kb genomic island in cheese Penicillium fungi, representing ca. 2% of the Penicillium roqueforti’s genome, that may confer selective advantage in the competing cheese environment where bacteria and fungi occur. Novel phylogenomic methods are being developed, revealing massive HGT among fungi. Altogether, these recent studies indicate that HGT is a crucial mechanism of rapid adaptation, even among eukaryotes.

Ocular Melanoma

Science.gov (United States)

... is Ocular Melanoma? Leer en Español: ¿Qué es el melanoma ocular? Written By: Daniel Porter Reviewed By: Robert H Janigian Jr MD Sep. 01, 2017 Ocular melanoma (melanoma in or around the eye) is a type of cancer that develops in the cells that produce pigment. ...

Direct plantlet inoculation with soil or insect-associated fungi may control cabbage root fly maggots.

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Razinger, Jaka; Lutz, Matthias; Schroers, Hans-Josef; Palmisano, Marilena; Wohler, Christian; Urek, Gregor; Grunder, Jürg

2014-07-01

A potential Delia radicum biological control strategy involving cauliflower plantlet inoculation with various fungi was investigated in a series of laboratory and glasshouse experiments. In addition to entomopathogenic fungi, fungi with a high rhizosphere competence and fungi with the ability to survive as saprotrophs in soil were tested. The following fungal species were evaluated in the experiments: Trichoderma atroviride, T. koningiopsis, T. gamsii, Beauveria bassiana, Metharhizium anisopliae, M. brunneum and Clonostachys solani. A commercial carbosulfan-based insecticide was used as a positive control. Additionally, two commercial products, one based on B. bassiana (Naturalis) and one on Bacillus thuringiensis (Delfin) were used as reference biocontrol agents. The aims were (i) to assess the pathogenicity of the selected fungal isolates to Delia radicum, (ii) to evaluate the fungal isolates' rhizosphere competence, with the emphasis on the persistence of the original inoculum on the growing roots, (iii) to assess possible endophytic plant tissue colonization, and (iv) to evaluate potential plant growth stimulating effects of the added inoculi. Significant pathogenicity of tested fungi against Delia radicum was confirmed in in vitro and glasshouse experiments. All tested fungi persisted on cauliflower rhizoplane. More importantly, the added fungi were found on thoroughly washed roots outside the original point of inoculation. This provided us with evidence that our tested fungi could be transferred via or grow with the elongating roots. In addition to colonizing the rhizoplane, some fungi were found inside the plant root or stem tissue, thus exhibiting endophytic characteristics. The importance of fungal ecology as a criterion in appropriate biological control agent selection is discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

Contrasting effects of necrotrophic and biotrophic plant pathogens on the aphid Aphis fabae

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Al-Naemi, F.; Hatcher, P. E.

2013-01-01

Phytophagous insects have to contend with a wide variation in food quality brought about by a variety of factors intrinsic and extrinsic to the plant. One of the most important factors is infection by plant pathogenic fungi. Necrotrophic and biotrophic plant pathogenic fungi may have contrasting effects on insect herbivores due to their different infection mechanisms and induction of different resistance pathways, although this has been little studied and there has been no study of their comb...

Differential Microbial Diversity in Drosophila melanogaster: Are Fruit Flies Potential Vectors of Opportunistic Pathogens?

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Luis A. Ramírez-Camejo

2017-01-01

Full Text Available Drosophila melanogaster has become a model system to study interactions between innate immunity and microbial pathogens, yet many aspects regarding its microbial community and interactions with pathogens remain unclear. In this study wild D. melanogaster were collected from tropical fruits in Puerto Rico to test how the microbiota is distributed and to compare the culturable diversity of fungi and bacteria. Additionally, we investigated whether flies are potential vectors of human and plant pathogens. Eighteen species of fungi and twelve species of bacteria were isolated from wild flies. The most abundant microorganisms identified were the yeast Candida inconspicua and the bacterium Klebsiella sp. The yeast Issatchenkia hanoiensis was significantly more common internally than externally in flies. Species richness was higher in fungi than in bacteria, but diversity was lower in fungi than in bacteria. The microbial composition of flies was similar internally and externally. We identified a variety of opportunistic human and plant pathogens in flies such as Alcaligenes faecalis, Aspergillus flavus, A. fumigatus, A. niger, Fusarium equiseti/oxysporum, Geotrichum candidum, Klebsiella oxytoca, Microbacterium oxydans, and Stenotrophomonas maltophilia. Despite its utility as a model system, D. melanogaster can be a vector of microorganisms that represent a potential risk to plant and public health.

Biological control of dodder (Cuscuta campestris L. by fungi pathogens

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F. Fallahpour

2016-04-01

Full Text Available Parasite weeds are the most important yield reducing factors, and among them dodder (Cuscuta campestris L. is an obligate parasite of many plant families. In order to find a suitable biocontrol agent for dodder a study was conducted based on a randomized complete design with four replications at research greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran during 2007-2009. Diseased dodders sampled from sugarbeet farms of Chenaran, Iran. After culturing and isolating exiting fungi from infected tissues of dodder, Fusarium sp., Alternaria sp. and Colletotrichum sp. were recognized. Inoculation of isolates was carried out with concenteration of 1×108 spores per ml sterile water at different growth stages of dodder in labratoary and greenhouse. Among different fungi, isolate of 323 of F. oxysporum showed an effective control on germination of dodder seeds and the highest level of plant pathogencity was before the contact of dodder with host and infection in older plants decreased. Infection of this isolate with crops such as sugarbeet (Beta vulgaris L., alfalfa (Medigago sativa L., basil (Ocimum basilicum L., wheat (Triticum aestivum L. and barley (Hordeum vulgare L. showed no symptoms.

An efficient method for DNA extraction from Cladosporioid fungi.

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Moslem, M A; Bahkali, A H; Abd-Elsalam, K A; Wit, P J G M

2010-11-23

We developed an efficient method for DNA extraction from Cladosporioid fungi, which are important fungal plant pathogens. The cell wall of Cladosporioid fungi is often melanized, which makes it difficult to extract DNA from their cells. In order to overcome this we grew these fungi for three days on agar plates and extracted DNA from mycelium mats after manual or electric homogenization. High-quality DNA was isolated, with an A(260)/A(280) ratio ranging between 1.6 and 2.0. Isolated genomic DNA was efficiently digested with restriction enzymes and produced distinct banding patterns on agarose gels for the different Cladosporium species. Clear DNA fragments from the isolated DNA were amplified by PCR using small and large subunit rDNA primers, demonstrating that this method provides DNA of sufficiently high quality for molecular analyses.

Dispersal of arbuscular mycorrhizal fungi and plants during succession

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García de León, David; Moora, Mari; Öpik, Maarja; Jairus, Teele; Neuenkamp, Lena; Vasar, Martti; Bueno, C. Guillermo; Gerz, Maret; Davison, John; Zobel, Martin

2016-11-01

Arbuscular mycorrhizal (AM) fungi are important root symbionts that enhance plant nutrient uptake and tolerance to pathogens and drought. While the role of plant dispersal in shaping successional vegetation is well studied, there is very little information about the dispersal abilities of AM fungi. We conducted a trap-box experiment in a recently abandoned quarry at 10 different distances from the quarry edge (i.e. the potential propagule source) over eleven months to assess the short term, within-year, arrival of plant and AM fungal assemblages and hence their dispersal abilities. Using DNA based techniques we identified AM fungal taxa and analyzed their phylogenetic diversity. Plant diversity was determined by transporting trap soil to a greenhouse and identifying emerging seedlings. We recorded 30 AM fungal taxa. These contained a high proportion of ruderal AM fungi (30% of taxa, 79% of sequences) but the richness and abundance of AM fungi were not related to the distance from the presumed propagule source. The number of sequences of AM fungi decreased over time. Twenty seven plant species (30% of them ruderal) were recorded from the soil seed traps. Plant diversity decreased with distance from the propagule source and increased over time. Our data show that AM fungi with ruderal traits can be fast colonizers of early successional habitats.

Friend or foe? Evolutionary history of glycoside hydrolase family 32 genes encoding for sucrolytic activity in fungi and its implications for plant-fungal symbioses

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James Timothy Y

2009-06-01

Full Text Available Abstract Background Many fungi are obligate biotrophs of plants, growing in live plant tissues, gaining direct access to recently photosynthesized carbon. Photosynthate within plants is transported from source to sink tissues as sucrose, which is hydrolyzed by plant glycosyl hydrolase family 32 enzymes (GH32 into its constituent monosaccharides to meet plant cellular demands. A number of plant pathogenic fungi also use GH32 enzymes to access plant-derived sucrose, but less is known about the sucrose utilization ability of mutualistic and commensal plant biotrophic fungi, such as mycorrhizal and endophytic fungi. The aim of this study was to explore the distribution and abundance of GH32 genes in fungi to understand how sucrose utilization is structured within and among major ecological guilds and evolutionary lineages. Using bioinformatic and PCR-based analyses, we tested for GH32 gene presence in all available fungal genomes and an additional 149 species representing a broad phylogenetic and ecological range of biotrophic fungi. Results We detected 9 lineages of GH32 genes in fungi, 4 of which we describe for the first time. GH32 gene number in fungal genomes ranged from 0–12. Ancestral state reconstruction of GH32 gene abundance showed a strong correlation with nutritional mode, and gene family expansion was observed in several clades of pathogenic filamentous Ascomycota species. GH32 gene number was negatively correlated with animal pathogenicity and positively correlated with plant biotrophy, with the notable exception of mycorrhizal taxa. Few mycorrhizal species were found to have GH32 genes as compared to other guilds of plant-associated fungi, such as pathogens, endophytes and lichen-forming fungi. GH32 genes were also more prevalent in the Ascomycota than in the Basidiomycota. Conclusion We found a strong signature of both ecological strategy and phylogeny on GH32 gene number in fungi. These data suggest that plant biotrophic fungi

Tomato Cf resistance proteins mediate recognition of cognate homologous effectors from fungi pathogenic on dicots and monocots.

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Stergiopoulos, Ioannis; van den Burg, Harrold A; Okmen, Bilal; Beenen, Henriek G; van Liere, Sabine; Kema, Gert H J; de Wit, Pierre J G M

2010-04-20

Most fungal effectors characterized so far are species-specific and facilitate virulence on a particular host plant. During infection of its host tomato, Cladosporium fulvum secretes effectors that function as virulence factors in the absence of cognate Cf resistance proteins and induce effector-triggered immunity in their presence. Here we show that homologs of the C. fulvum Avr4 and Ecp2 effectors are present in other pathogenic fungi of the Dothideomycete class, including Mycosphaerella fijiensis, the causal agent of black Sigatoka disease of banana. We demonstrate that the Avr4 homolog of M. fijiensis is a functional ortholog of C. fulvum Avr4 that protects fungal cell walls against hydrolysis by plant chitinases through binding to chitin and, despite the low overall sequence homology, triggers a Cf-4-mediated hypersensitive response (HR) in tomato. Furthermore, three homologs of C. fulvum Ecp2 are found in M. fijiensis, one of which induces different levels of necrosis or HR in tomato lines that lack or contain a putative cognate Cf-Ecp2 protein, respectively. In contrast to Avr4, which acts as a defensive virulence factor, M. fijiensis Ecp2 likely promotes virulence by interacting with a putative host target causing host cell necrosis, whereas Cf-Ecp2 could possibly guard the virulence target of Ecp2 and trigger a Cf-Ecp2-mediated HR. Overall our data suggest that Avr4 and Ecp2 represent core effectors that are collectively recognized by single cognate Cf-proteins. Transfer of these Cf genes to plant species that are attacked by fungi containing these cognate core effectors provides unique ways for breeding disease-resistant crops.

Wild Honey Inhibits Growth od Some Phytopathogenic Fungi in vitro

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K.I. Al-Mughrabi

2003-01-01

Wild honey was diluted to 1000 ppm with sterile distilled water and tested in vitro for inhibition of the plant pathogenic fungi Fusarium oxysporum, Rhizoctonia solani, Alternaria solani, Stemphylium solani, Colletotrichum sp., and Phytophthora infestans. Wild honey was effective against all these fungi, particularly A. solani and P. infestans, the causal agents of early and late blight diseases respectively; also against R. solani and F. oxysporum, and to a less extent against S....

Detecção, transmissão e patogenicidade de fungos em sementes de angico-vermelho (Parapiptadenia rigida Detection, transmission and pathogenicity of fungi on seeds of Parapiptadenia rigida ("angico-vermelho"

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Caciara Gonzatto Maciel

2012-12-01

Full Text Available Angico-vermelho (Parapiptadenia rigida (Benth. Brenan é uma espécie nativa de grande valor ecológico e econômico, importante para a recomposição de áreas degradadas. O presente trabalho avaliou incidência, transmissão e patogenicidade de fungos associados a sementes de angico-vermelho de distintas procedências do Estado do Rio Grande do Sul. Para isso, utilizaram-se três amostras de sementes, com as quais realizaram-se testes de germinação, sanidade empregando-se o método do papel-filtro (PF e de plaqueamento em batata-dextrose-ágar (BDA, transmissão e patogenicidade dos fungos. A germinação das sementes de angico-vermelho variou de 63 a 91 %. Os fungos considerados potencialmente patogênicos encontrados associados as sementes de angico-vermelho foram: Alternaria sp.; Botrytis sp.; Fusarium sp.; Cladosporium sp. e Pestalotia sp.; sendo que Fusarium sp. foi detectado em todas as amostras pelo método PF, e foi transmitido via semente causando má formação do sistema radicular e dos cotilédones e tombamento de pré emergência. Sua patogenicidade foi confirmada."Angico-vermelho" (Parapiptadenia rigida (Benth. Brenan is a native species of great ecological and economic importance for the recovery of degraded areas. This study evaluated the incidence, the transmission and the pathogenicity of fungi associated with "angico-vermelho" seeds from different provenances of the state of Rio Grande do Sul. Thus, we used three samples of seeds, with which germination and sanity tests were carried out by adopting the methods of filter paper (FP, plating on potato dextrose agar (PDA, transmission and pathogenicity of fungi. Germination of "angico-vermelho" seeds ranged from 63-91%. The fungi considered potentially pathogenic and found associated with "angico-vermelho" seeds were: Alternaria sp.; Botrytis sp.; Fusarium sp.; Cladosporium sp. and Pestalotia sp.. Fusarium sp. was detected in all samples according to the FP method and was

Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi

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Fungi of the phylum Basidiomycota (basidiomycetes) make up some 37% of the described fungi and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprotrophs including the majority of wood decaying and ectomycorrhizal species. To b...

Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil

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Helena M.B. Oliveira

2016-03-01

Full Text Available Filamentous fungi in drinking water distribution systems are known to (a block water pipes; (b cause organoleptic biodeterioration; (c act as pathogens or allergens and (d cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife—Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively, followed by Trichoderma and Fusarium (9% each, Curvularia (5% and finally the species Pestalotiopsis karstenii (2%. Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens.

Importance of seed-borne fungi of sorghum and pearl millet in Burkina Faso and their control using plant extracts.

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Zida, Pawindé Elisabeth; Sérémé, Paco; Leth, Vibeke; Sankara, Philippe; Somda, Irénée; Néya, Adama

2008-02-01

Seed-borne fungi of sorghum and pearl millet in Burkina Faso were surveyed. A total of 188 seed samples from various locations, collected in 1989 (42) and 2002 (146), were tested, using the blotter, dry inspection and washing methods. Infection experiments were carried out with the major fungi recorded on each crop by the blotter test. Six essential oils of plants were investigated for their inhibitory activity against eight pathogenic fungi. Thirty four and 27 fungal species were found in seed samples of sorghum and pearl millet, respectively. Phoma sp. and Fusarium moniliforme infected 95 to 100% of the seed samples of both sorghum and pearl millet. Sphacelotheca sorghi and Tolyposporium ehrenbergii were encountered in respectively, 75 and 33% of seed samples of sorghum. T. penicillariae, Sclerospora graminicola and Claviceps fusiformis were present in 88, 41 and 32% of seed samples of pearl millet, respectively. Seeds inoculated with Acremonium strictum, Curvularia oryzae, F. equiseti, F. moniliforme and F. subglutinans and sown in sterilized soil, showed considerable mortality of the seedlings. Three essential oils inhibited in vitro the mycelial growth of all the fungi used by 85 to 100% and reduced significantly sorghum and pearl millet seed infection rates of Phoma sp., Fusarium sp., Curvularia sp., Colletotrichum graminicola and Exserohilum sp. Presence of many pathogenic fungi in considerable number of seed samples indicates the need of field surveys for these and other pathogens. Development of plant extracts for the control of seed-borne pathogens and public awareness on seed-borne diseases management measures for maintaining quality seed should be increased.

A comparative genome analysis of Cercospora sojina with other members of the pathogen genus Mycosphaerella on different plant hosts

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Fanchang Zeng

2017-09-01

Full Text Available Fungi are the causal agents of many of the world's most serious plant diseases causing disastrous consequences for large-scale agricultural production. Pathogenicity genomic basis is complex in fungi as multicellular eukaryotic pathogens. Here, we report the genome sequence of C. sojina, and comparative genome analysis with plant pathogen members of the genus Mycosphaerella (Zymoseptoria. tritici (synonyms M. graminicola, M. pini, M. populorum and M. fijiensis - pathogens of wheat, pine, poplar and banana, respectively. Synteny or collinearity was limited between genomes of major Mycosphaerella pathogens. Comparative analysis with these related pathogen genomes indicated distinct genome-wide repeat organization features. It suggests repetitive elements might be responsible for considerable evolutionary genomic changes. These results reveal the background of genomic differences and similarities between Dothideomycete species. Wide diversity as well as conservation on genome features forms the potential genomic basis of the pathogen specialization, such as pathogenicity to woody vs. herbaceous hosts. Through comparative genome analysis among five Dothideomycete species, our results have shed light on the genome features of these related fungi species. It provides insight for understanding the genomic basis of fungal pathogenicity and disease resistance in the crop hosts.

Miopatia ocular descendente Descending ocular myopathy: a case report

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Marcos R. G. de Freitas

1975-06-01

Full Text Available Os autores apresentam caso de paciente jovem, do sexo feminino, com afecção muscular primária ocular e faríngea sem caráter familial. Foram feitos estudos eletromiográficos e histopatológicos musculares que confirmam o caráter miogênico do processo. É feita comparação entre a miopatia ocular e a miopatia ocular descendente, acreditando os autores que seriam variantesThe case of a 23 years old female patient, with primary involvement of the extraocular and faringeal muscles without familiar history is reported. Electromyographic and muscular biopsy studies proved the myogenic nature of the process. A clinical comparison between the ocular myopathy and the descending ocular myopathy is made, the authors thinking that both of them would be variants of the same muscle disease.

The Ecological Genomics of Fungi: Repeated Elements in Filamentous Fungi with a Focus on Wood-Decay Fungi

Energy Technology Data Exchange (ETDEWEB)

Murat, Claude [INRA, Nancy, France; Payen, Thibaut [INRA, Nancy, France; Petitpierre, Denis [INRA, Nancy, France; Labbe, Jessy L [ORNL

2013-01-01

In the last decade, the genome of several dozen filamentous fungi have been sequenced. Interestingly, vast diversity in genome size was observed (Fig. 2.1) with 14-fold differences between the 9 Mb of the human pathogenic dandruff fungus (Malassezia globosa; Xu, Saunders, et al., 2007) and the 125 Mb of the ectomycorrhizal black truffle of P rigord (Tuber melanosporum; Martin, Kohler, et al., 2010). Recently, Raffaele and Kamoun (2012) highlighted that the genomes of several lineages of filamentous plant pathogens have been shaped by repeat-driven expansion. Indeed, repeated elements are ubiquitous in all prokaryote and eukaryote genomes; however, their frequencies can vary from just a minor percentage of the genome to more that 60 percent of the genome. Repeated elements can be classified in two major types: satellites DNA and transposable elements. In this chapter, the different types of repeated elements and how these elements can impact genome and gene repertoire will be described. Also, an intriguing link between the transposable elements richness and diversity and the ecological niche will be highlighted.

Pathogenic fungi and parasitoids of aphids present in air captures of migratory alates in the low-latitude plateau of Yunnan, China.

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Huang, Zhi-Hong; Feng, Ming-Guang; Chen, Xue-Xin; Liu, Shu-Sheng

2008-10-01

To survey fungal pathogens and parasitoids of aphids in the low-latitude plateau of Yunnan, southwest China, 3,553 migratory alates of Brevicoryne brassicae, Lipaphis erysimi, and Myzus persicae were attracted to a yellow-plus-plant trap from air during a full-year period and individually reared on cabbage leaves for 7-14 d at 18-22 degrees C and L:D 12:12. Among the trapped alates, 19.2% were killed by 10 species of aphid-pathogenic fungi after survival of 2.3 d (range, 1-7 d). Another 2.8% were mummified by the wasps Aphidius gifuensis, Diaeretella rapae, Ephedrus plagiator, and Aphelinus mali after survival of 4.9 d (range, 1-11 d). Most of the mycosed alates (77.8%) died from Entomophthorales predominated by Pandora neoaphidis (42.7%) and Zoophthora radicans (14.5%), followed by P. nouryi, Neozygites fresenii, Conidiobiolus spp., Entomophthora planchoniana, and Z. aphidis in decreasing frequencies. A mitosporic fungus, Lecanicillium lecanii, was found frequently in L. erysimi alates trapped in rainy season. However, B. brassicae alates captured in dry season were infected or parasitized very occasionally. The predeath fecundity of the infected or parasitized alates warranted successful colonization on plants, although greatly reduced, and was well shown by the fitted probability for a given fecundity per capita and the increasing mean size of their progeny colonies. Contagious transmission of the alate-borne mycosis in most of the colonies caused high progeny mortalities within 14 d. The results highlight for the first time the diversity of aphid pathogens and the spread of both pathogens and parasitoids with host dispersal flight in the low-latitude plateau.

Genome analysis of the necrotrophic fungal pathogens Sclerotinia sclerotiorum and Botrytis cinerea

NARCIS (Netherlands)

Amselem, J.; Cuomo, C.A.; Kan, van J.A.L.; Viaud, M.; Benito, E.P.; Couloux, A.; Coutinho, P.M.; Vries, de R.P.; Dyer, P.S.; Fillinger, S.; Fournier, E.; Gout, L.; Hahn, M.; Kohn, L.; Lapalu, N.; Plummer, K.M.; Pradier, J.M.; Quévillon, E.; Sharon, A.; Simon, A.; Have, ten A.; Tudzynski, B.; Tudzynski, P.; Wincker, P.; Andrew, M.; Anthouard, V.; Beever, R.E.; Beffa, R.; Benoit, I.; Bouzid, O.; Brault, B.; Chen, Z.; Choquer, M.; Collemare, J.; Cotton, P.; Danchin, E.G.; Silva, Da C.; Gautier, A.; Giraud, C.; Giraud, T.; Gonzalez, C.; Grossetete, S.; Güldener, U.; Henrissat, B.; Howlett, B.J.; Kodira, C.; Kretschmer, M.; Lappartient, A.; Leroch, M.; Levis, C.; Mauceli, E.; Neuvéglise, C.; Oeser, B.; Pearson, M.; Poulain, J.; Poussereau, N.; Quesneville, H.; Rascle, C.; Schumacher, J.; Ségurens, B.; Sexton, A.; Silva, E.; Sirven, C.; Soanes, D.M.; Talbot, N.J.; Templeton, M.; Yandava, C.; Yarden, O.; Zeng, Q.; Rollins, J.A.; Lebrun, M.H.; Dickman, M.

2011-01-01

Sclerotinia sclerotiorum and Botrytis cinerea are closely related necrotrophic plant pathogenic fungi notable for their wide host ranges and environmental persistence. These attributes have made these species models for understanding the complexity of necrotrophic, broad host-range pathogenicity.

Aerobic bacteria and fungi from skin lesions of fish in Khartoum state

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Walaa Hassan Ibrahim

2016-12-01

Conclusion: Fishes with skin lesions are harboring many pathogenic bacteria and fungi and may act as a source of zoonotic infections and can transmit several pathogens to workers in fish industry and consumers. Therefore, thorough and strict routine inspection of fish is recommended to ensure safety and that there are no serious risks to consumers. [J Adv Vet Anim Res 2016; 3(4.000: 375-385

Entomopathogenic fungi on Hemiberlesia pitysophila.

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Chengqun Lv

Full Text Available Hemiberlesia pitysophila Takagi is an extremely harmful exotic insect in forest to Pinus species, including Pinus massoniana. Using both morphological taxonomy and molecular phylogenetics, we identified 15 strains of entomogenous fungi, which belong to 9 genera with high diversities. Surprisingly, we found that five strains that were classified as species of Pestalotiopsis, which has been considered plant pathogens and endophytes, were the dominant entomopathogenic fungus of H. pitysophila. Molecular phylogenetic tree established by analyzing sequences of ribosomal DNA internal transcribed spacer showed that entomopathogenic Pestalotiopsis spp. were similar to plant Pestalotiopsis, but not to other pathogens and endophytes of its host plant P. massoniana. We were the first to isolate entomopathogenic Pestalotiopsis spp. from H. pitysophila. Our findings suggest a potential and promising method of H. pitysophila bio-control.

Entomopathogenic fungi on Hemiberlesia pitysophila.

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Lv, Chengqun; Huang, Baoling; Qiao, Mengji; Wei, Jiguang; Ding, Bo

2011-01-01

Hemiberlesia pitysophila Takagi is an extremely harmful exotic insect in forest to Pinus species, including Pinus massoniana. Using both morphological taxonomy and molecular phylogenetics, we identified 15 strains of entomogenous fungi, which belong to 9 genera with high diversities. Surprisingly, we found that five strains that were classified as species of Pestalotiopsis, which has been considered plant pathogens and endophytes, were the dominant entomopathogenic fungus of H. pitysophila. Molecular phylogenetic tree established by analyzing sequences of ribosomal DNA internal transcribed spacer showed that entomopathogenic Pestalotiopsis spp. were similar to plant Pestalotiopsis, but not to other pathogens and endophytes of its host plant P. massoniana. We were the first to isolate entomopathogenic Pestalotiopsis spp. from H. pitysophila. Our findings suggest a potential and promising method of H. pitysophila bio-control.

Caveolins and caveolae in ocular physiology and pathophysiology.

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Gu, Xiaowu; Reagan, Alaina M; McClellan, Mark E; Elliott, Michael H

2017-01-01

Caveolae are specialized, invaginated plasma membrane domains that are defined morphologically and by the expression of signature proteins called, caveolins. Caveolae and caveolins are abundant in a variety of cell types including vascular endothelium, glia, and fibroblasts where they play critical roles in transcellular transport, endocytosis, mechanotransduction, cell proliferation, membrane lipid homeostasis, and signal transduction. Given these critical cellular functions, it is surprising that ablation of the caveolae organelle does not result in lethality suggesting instead that caveolae and caveolins play modulatory roles in cellular homeostasis. Caveolar components are also expressed in ocular cell types including retinal vascular cells, Müller glia, retinal pigment epithelium (RPE), conventional aqueous humor outflow cells, the corneal epithelium and endothelium, and the lens epithelium. In the eye, studies of caveolae and other membrane microdomains (i.e., "lipid rafts") have lagged behind what is a substantial body of literature outside vision science. However, interest in caveolae and their molecular components has increased with accumulating evidence of important roles in vision-related functions such as blood-retinal barrier homeostasis, ocular inflammatory signaling, pathogen entry at the ocular surface, and aqueous humor drainage. The recent association of CAV1/2 gene loci with primary open angle glaucoma and intraocular pressure has further enhanced the need to better understand caveolar functions in the context of ocular physiology and disease. Herein, we provide the first comprehensive review of literature on caveolae, caveolins, and other membrane domains in the context of visual system function. This review highlights the importance of caveolae domains and their components in ocular physiology and pathophysiology and emphasizes the need to better understand these important modulators of cellular function. Copyright © 2016 Elsevier Ltd. All

53 review article a review of the virulence factors of pathogenic fungi

African Journals Online (AJOL)

boaz

individuals, invasive opportunistic infections occur in ... hyphae, this new cell divides to form the ascospores within the ascus. ... mould. These branching cellular units are known as .... Fe is needed by the fungi for growth, respiration and.

Molecular relationships of fungi within the Fusarium redolens - F. hostae clade

NARCIS (Netherlands)

Baayen, R.P.; O'Donnell, K.; Breeuwsma, S.; Geiser, D.M.; Waalwijk, C.

2001-01-01

The evolutionary relationships of fungi in the Fusarium redolens - F. hostae clade were investigated by constructing nuclear and mitochondrial gene genealogies for 37 isolates representing the known genetic and pathogenic diversity of this lineage, together with 15 isolates from putative sister

Human pathogenic bacteria, fungi, and viruses in Drosophila

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Panayidou, Stavria; Ioannidou, Eleni; Apidianakis, Yiorgos

2014-01-01

Drosophila has been the invertebrate model organism of choice for the study of innate immune responses during the past few decades. Many Drosophila–microbe interaction studies have helped to define innate immunity pathways, and significant effort has been made lately to decipher mechanisms of microbial pathogenesis. Here we catalog 68 bacterial, fungal, and viral species studied in flies, 43 of which are relevant to human health. We discuss studies of human pathogens in flies revealing not only the elicitation and avoidance of immune response but also mechanisms of tolerance, host tissue homeostasis, regeneration, and predisposition to cancer. Prominent among those is the emerging pattern of intestinal regeneration as a defense response induced by pathogenic and innocuous bacteria. Immunopathology mechanisms and many microbial virulence factors have been elucidated, but their relevance to human health conventionally necessitates validation in mammalian models of infection. PMID:24398387

Co-occurrence and hybridization of anther-smut pathogens specialized on Dianthus hosts.

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Petit, Elsa; Silver, Casey; Cornille, Amandine; Gladieux, Pierre; Rosenthal, Lisa; Bruns, Emily; Yee, Sarah; Antonovics, Janis; Giraud, Tatiana; Hood, Michael E

2017-04-01

Host specialization has important consequences for the diversification and ecological interactions of obligate pathogens. The anther-smut disease of natural plant populations, caused by Microbotryum fungi, has been characterized by specialized host-pathogen interactions, which contribute in part to the isolation among these numerous fungal species. This study investigated the molecular variation of Microbotryum pathogens within the geographic and host-specific distributions on wild Dianthus species in southern European Alps. In contrast to prior studies on this pathogen genus, a range of overlapping host specificities was observed for four delineated Microbotryum lineages on Dianthus hosts, and their frequent co-occurrence within single-host populations was quantified at local and regional scales. In addition to potential consequences for direct pathogen competition, the sympatry of Microbotryum lineages led to hybridization between them in many populations, and these admixed genotypes suffered significant meiotic sterility. Therefore, this investigation of the anther-smut fungi reveals how variation in the degrees of host specificity can have major implications for ecological interactions and genetic integrity of differentiated pathogen lineages. © 2017 John Wiley & Sons Ltd.

Chemical constituents from Melodorum fruticosum Lour. flowers against plant pathogenic fungi

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Rachsawan Mongkol

2016-07-01

Full Text Available The antifungal activity of hexane, dichloromethane and methanol extracts of 45 Thai plants were in vitro screened against plant phytopathogenic fungi (Alternaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora parasitica. Seven extracts strongly inhibited the mycelial growth of fungi. The plant extracts with highest antifungal activity were Limnophila aromatic, Eupatorium odoratum, Melodorum fruticosum and Alpinia galanga with 70%, 58%, 74% and 100% inhibition, respectively. The potent dichloromethane extract from M. fruticosum flowers was separated using bioassay guided against P. parasitica. Eight compounds: 1-hexacosanol (1, 5-hydroxy-7-methoxyflavone (2, β-sitosterol (3, melodorinone B (4, benzoic acid (5, chrysin (6, melodorinol (7 and melodorinone A (8 could be isolated. Among the isolated compounds, benzoic acid (5 and melodorinol (7 exhibited strong activity against mycelial growth of P. parasitica at 100% and 93% inhibition with the half maximal inhibitory concentration (IC50 values of 108 μg/mL and 130 μg/mL, respectively. This plant could be exploited for eco-friendly management control of plant diseases.

Effector proteins of rust fungi.

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Petre, Benjamin; Joly, David L; Duplessis, Sébastien

2014-01-01

Rust fungi include many species that are devastating crop pathogens. To develop resistant plants, a better understanding of rust virulence factors, or effector proteins, is needed. Thus far, only six rust effector proteins have been described: AvrP123, AvrP4, AvrL567, AvrM, RTP1, and PGTAUSPE-10-1. Although some are well established model proteins used to investigate mechanisms of immune receptor activation (avirulence activities) or entry into plant cells, how they work inside host tissues to promote fungal growth remains unknown. The genome sequences of four rust fungi (two Melampsoraceae and two Pucciniaceae) have been analyzed so far. Genome-wide analyses of these species, as well as transcriptomics performed on a broader range of rust fungi, revealed hundreds of small secreted proteins considered as rust candidate secreted effector proteins (CSEPs). The rust community now needs high-throughput approaches (effectoromics) to accelerate effector discovery/characterization and to better understand how they function in planta. However, this task is challenging due to the non-amenability of rust pathosystems (obligate biotrophs infecting crop plants) to traditional molecular genetic approaches mainly due to difficulties in culturing these species in vitro. The use of heterologous approaches should be promoted in the future.

Photodynamic treatment with phenothiazinium photosensitizers kills both ungerminated and germinated microconidia of the pathogenic fungi Fusarium oxysporum, Fusarium moniliforme and Fusarium solani.

Science.gov (United States)

de Menezes, Henrique Dantas; Tonani, Ludmilla; Bachmann, Luciano; Wainwright, Mark; Braga, Gilberto Úbida Leite; von Zeska Kress, Marcia Regina

2016-11-01

The search for alternatives to control microorganisms is necessary both in clinical and agricultural areas. Antimicrobial photodynamic treatment (APDT) is a promising light-based approach that can be used to control both human and plant pathogenic fungi. In the present study, we evaluated the effects of photodynamic treatment with red light and four phenothiazinium photosensitizers (PS): methylene blue (MB), toluidine blue O (TBO), new methylene blue N (NMBN) and the phenothiazinium derivative S137 on ungerminated and germinated microconidia of Fusarium oxysporum, F. moniliforme, and F. solani. APDT with each PS killed efficiently both the quiescent ungerminated microconidia and metabolically active germinated microconidia of the three Fusarium species. Washing away the unbound PS from the microconidia (both ungerminated and germinated) before red light exposure reduced but did not prevent the effect of APDT. Subcelullar localization of PS in ungerminated and germinated microconidia and the effects of photodynamic treatment on cell membranes were also evaluated in the three Fusarium species. APDT with MB, TBO, NMBN or S137 increased the membrane permeability in microconidia and APDT with NMBN or S137 increased the lipids peroxidation in microconidia of the three Fusarium species. These findings expand the understanding of photodynamic inactivation of filamentous fungi with phenothiazinium PS. Copyright © 2016 Elsevier B.V. All rights reserved.

Using hierarchical clustering of secreted protein families to classify and rank candidate effectors of rust fungi

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Rust fungi are obligate biotrophic pathogens causing considerable damage on crop plants. P. graminis f. sp. tritici, the causal agent of wheat stem rust, and M. larici-populina, the poplar rust pathogen, have strong deleterious impact on wheat and poplar wood production, respectively. The recently r...

Correction: Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi

Science.gov (United States)

2014-01-01

. Importantly, cellulases of some GH families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also revealed a complex history of lineage-specific expansions and attritions for the PL1 family. Conclusions Our study provides insights into the variety and expansion of fungal CAZyme classes and revealed the relationship of CAZyme size and diversity with their nutritional strategy and host specificity. PMID:24422981

Identification and Characterization of Pathogenic and Endophytic Fungal Species Associated with Pokkah Boeng Disease of Sugarcane

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Angelyn Hilton

2017-06-01

Full Text Available Pokkah Boeng is a serious disease of sugarcane, which can lead to devastating yield losses in crop-producing regions, including southern China. However, there is still uncertainty about the causal agent of the disease. Our aim was to isolate and characterize the pathogen through morphological, physiological, and molecular analyses. We isolated sugarcane-colonizing fungi in Fujian, China. Isolated fungi were first assessed for their cell wall degrading enzyme capabilities, and five isolates were identified for further analysis. Internal transcribed spacer sequencing revealed that these five strains are Fusarium, Alternaria, Phoma, Phomopsis, and Epicoccum. The Fusarium isolate was further identified as F. verticillioides after Calmodulin and EF-1α gene sequencing and microscopic morphology study. Pathogenicity assay confirmed that F. verticillioides was directly responsible for disease on sugarcane. Co-inoculation of F. verticillioides with other isolated fungi did not lead to a significant difference in disease severity, refuting the idea that other cellulolytic fungi can increase disease severity as an endophyte. This is the first report characterizing pathogenic F. verticillioides on sugarcane in southern China.

Complete genome sequence of Serratia sp. YD25 (KCTC 42987) presenting strong antagonistic activities to various pathogenic fungi and bacteria.

Science.gov (United States)

Su, Chun; Liu, Yibo; Sun, Yan; Li, Zhi

2017-03-10

Serratia sp. YD25 (KCTC 42987) was originally isolated from rhizosphere soil in a continuous cropping tobacco-planting farm. Here, we show that its metabolites efficiently suppress the growth of various important pathogenic fungi and bacteria, causing infection in both plants and humans. In addition, Serratia sp. YD25 has a special trait of simultaneous production of both serrawettin W2 and prodigiosin, two important bioactive secondary metabolites produced by Serratia strains. Such co-production has not been reported in other Serratia strains. The complete genome sequence of Serratia sp. YD25 is presented, which is valuable for further exploration of its biotechnological applications in agriculture and medicine. The genome sequence reported here is also useful for understanding the unique regulatory mechanisms underlying biosynthesis of active compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Developing hygiene protocols against mechanically transmitted pathogens in greenhouse tomato production systems

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Greenhouse tomato propagation and production require intensive crop work that promotes the spread of mechanically transmitted pathogens (e.g. fungi, bacteria, viruses and viroids). Therefore, a clean seed program is very important to prevent any un-intentional introduction of seed-borne pathogens t...

Specific interactions between arbuscular mycorrhizal fungi and plant growth-promoting bacteria--as revealed by different combinations

Energy Technology Data Exchange (ETDEWEB)

Jaderlund, Lotta; Arthurson, Veronica; Granhall, Ulf; Jansson, Janet K.

2008-05-15

The interactions between two plant growth promoting rhizobacteria (PGPR), Pseudomonas fluorescens SBW25 and Paenibacillus brasilensis PB177, two arbuscular mycorrhizal (AM) fungi (Glomus mosseae and G. intraradices) and one pathogenic fungus (Microdochium nivale) were investigated on winter wheat (Triticum aestivum cultivar Tarso) in a greenhouse trial. PB177, but not SBW25, had strong inhibitory effects on M. nivale in dual culture plate assays. The results from the greenhouse experiment show very specific interactions; e.g. the two AM fungi react differently when interacting with the same bacteria on plants. G. intraradices (single inoculation or together with SBW25) increased plant dry weight on M. nivale infested plants, suggesting that the pathogenic fungus is counteracted by G. intraradices, but PB177 inhibited this positive effect. This is an example of two completely different reactions between the same AM fungus and two species of bacteria, previously known to enhance plant growth and inhibit pathogens. When searching for plant growth promoting microorganisms it is therefore important to test for the most suitable combination of plant, bacteria and fungi in order to get satisfactory plant growth benefits.

Genome-wide analyses of the Dutch elm disease fungi

Science.gov (United States)

Louis. Bernier

2017-01-01

The Ascomycete fungi Ophiostoma ulmi and O. novo-ulmi are the pathogens respectively responsible for the two successive pandemics of Dutch elm disease (DED) since the early 1900s. The advent of the highly fit and virulent O. novo-ulmi was a landmark event in the evolution of DED during the last 100 years....

Phytotoxins Produced by Fungi Associated with Grapevine Trunk Diseases

Science.gov (United States)

Andolfi, Anna; Mugnai, Laura; Luque, Jordi; Surico, Giuseppe; Cimmino, Alessio; Evidente, Antonio

2011-01-01

Up to 60 species of fungi in the Botryosphaeriaceae family, genera Cadophora, Cryptovalsa, Cylindrocarpon, Diatrype, Diatrypella, Eutypa, Eutypella, Fomitiporella, Fomitiporia, Inocutis, Phaeoacremonium and Phaeomoniella have been isolated from decline-affected grapevines all around the World. The main grapevine trunk diseases of mature vines are Eutypa dieback, the esca complex and cankers caused by the Botryospheriaceae, while in young vines the main diseases are Petri and black foot diseases. To understand the mechanism of these decline-associated diseases and the symptoms associated with them, the toxins produced by the pathogens involved in these diseases were isolated and characterised chemically and biologically. So far the toxins of only a small number of these decline fungi have been studied. This paper presents an overview of the toxins produced by the most serious of these vine wood pathogens: Eutypa lata, Phaeomoniella chlamydospora, Phaeoacremonium aleophilum and some taxa in the Botryosphaeriaceae family, and examines how these toxins produce decline symptoms. The chemical structure of these metabolites and in some cases their vivotoxin nature are also discussed. PMID:22295177

Phytotoxins Produced by Fungi Associated with Grapevine Trunk Diseases

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Antonio Evidente

2011-12-01

Full Text Available Up to 60 species of fungi in the Botryosphaeriaceae family, genera Cadophora, Cryptovalsa, Cylindrocarpon, Diatrype, Diatrypella, Eutypa, Eutypella, Fomitiporella, Fomitiporia, Inocutis, Phaeoacremonium and Phaeomoniella have been isolated from decline-affected grapevines all around the World. The main grapevine trunk diseases of mature vines are Eutypa dieback, the esca complex and cankers caused by the Botryospheriaceae, while in young vines the main diseases are Petri and black foot diseases. To understand the mechanism of these decline-associated diseases and the symptoms associated with them, the toxins produced by the pathogens involved in these diseases were isolated and characterised chemically and biologically. So far the toxins of only a small number of these decline fungi have been studied. This paper presents an overview of the toxins produced by the most serious of these vine wood pathogens: Eutypa lata, Phaeomoniella chlamydospora, Phaeoacremonium aleophilum and some taxa in the Botryosphaeriaceae family, and examines how these toxins produce decline symptoms. The chemical structure of these metabolites and in some cases their vivotoxin nature are also discussed.

Efficacy of Origanum essential oils for inhibition of potentially pathogenic fungi

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Nadábia Almeida B Souza

2010-09-01

Full Text Available This study aimed to assess the efficacy of O. vulgare L. and O. majorana L. essential oil in inhibiting the growth and survival of potentially pathogenic fungal strains and also sought to evaluate the possible mechanisms involved in the establishment of the antifungal property of the tested essential oils through assays of osmotic stability and morphogenesis. Test strains included in this study were Candida albicans ATCC 7645, C. tropicalis LM-14, C. krusei LM-09, Cryptococcus neoformans FGF-5, Aspergillus flavus LM-02, A. fumigatus IPP-21, T. rubrum ATCC 28184, T. mentagrophytes LM-64, Microsporum gypseum ATCC 184, M. canis LM-36 and Cladosporium herbarium ATCC 26362. O. vulgare essential oil presented a MIC value of 80 µL/mL, while for O. majorana this was 160 µL/mL. C. krusei LM-09 was the only strain resistant to all assayed concentrations of both essential oils. O. vulgare and O. majorana essential oil at their MIC values provided a cidal effect against C. albicans ATCC 7645 after 4 h of exposure. O. vulgare essential oil at 80 µL/mL exhibited 100 % inhibition of the radial mycelia growth of T. rubrum ATCC 28184 and M. canis LM-36 for 14 days. Assayed fungus strain protected by sorbitol (osmo-protectant agent grew in media containing higher concentrations of O. vulgare and O. majorana essential oil in comparison to media without sorbitol, suggesting some specificity of these essential oils for targeting cell wall in the fungi cell. Main morphological changes observed under light microscopy provided by the essential oil of O. vulgare in A. flavus LM-02 were decreased conidiation, leakage of cytoplasm, loss of pigmentation and disrupted cell structure indicating fungal wall degeneration. These results suggest that essential oils from Origanum could be regarded as a potential antifungal compound for controlling the growth of pathogen fungi and the occurrence of mycoses.O objetivo deste estudo foi observar a eficácia do óleo essencial de O

Cluster bomb ocular injuries.

Science.gov (United States)

Mansour, Ahmad M; Hamade, Haya; Ghaddar, Ayman; Mokadem, Ahmad Samih; El Hajj Ali, Mohamad; Awwad, Shady

2012-01-01

To present the visual outcomes and ocular sequelae of victims of cluster bombs. This retrospective, multicenter case series of ocular injury due to cluster bombs was conducted for 3 years after the war in South Lebanon (July 2006). Data were gathered from the reports to the Information Management System for Mine Action. There were 308 victims of clusters bombs; 36 individuals were killed, of which 2 received ocular lacerations and; 272 individuals were injured with 18 receiving ocular injury. These 18 surviving individuals were assessed by the authors. Ocular injury occurred in 6.5% (20/308) of cluster bomb victims. Trauma to multiple organs occurred in 12 of 18 cases (67%) with ocular injury. Ocular findings included corneal or scleral lacerations (16 eyes), corneal foreign bodies (9 eyes), corneal decompensation (2 eyes), ruptured cataract (6 eyes), and intravitreal foreign bodies (10 eyes). The corneas of one patient had extreme attenuation of the endothelium. Ocular injury occurred in 6.5% of cluster bomb victims and 67% of the patients with ocular injury sustained trauma to multiple organs. Visual morbidity in civilians is an additional reason for a global ban on the use of cluster bombs.

Genome Sequencing and Comparative Transcriptomics of the Model Entomopathogenic Fungi Metarhizium anisopliae and M. acridum

Science.gov (United States)

Shang, Yanfang; Duan, Zhibing; Hu, Xiao; Xie, Xue-Qin; Zhou, Gang; Peng, Guoxiong; Luo, Zhibing; Huang, Wei; Wang, Bing; Fang, Weiguo; Wang, Sibao; Zhong, Yi; Ma, Li-Jun; St. Leger, Raymond J.; Zhao, Guo-Ping; Pei, Yan; Feng, Ming-Guang; Xia, Yuxian; Wang, Chengshu

2011-01-01

Metarhizium spp. are being used as environmentally friendly alternatives to chemical insecticides, as model systems for studying insect-fungus interactions, and as a resource of genes for biotechnology. We present a comparative analysis of the genome sequences of the broad-spectrum insect pathogen Metarhizium anisopliae and the acridid-specific M. acridum. Whole-genome analyses indicate that the genome structures of these two species are highly syntenic and suggest that the genus Metarhizium evolved from plant endophytes or pathogens. Both M. anisopliae and M. acridum have a strikingly larger proportion of genes encoding secreted proteins than other fungi, while ∼30% of these have no functionally characterized homologs, suggesting hitherto unsuspected interactions between fungal pathogens and insects. The analysis of transposase genes provided evidence of repeat-induced point mutations occurring in M. acridum but not in M. anisopliae. With the help of pathogen-host interaction gene database, ∼16% of Metarhizium genes were identified that are similar to experimentally verified genes involved in pathogenicity in other fungi, particularly plant pathogens. However, relative to M. acridum, M. anisopliae has evolved with many expanded gene families of proteases, chitinases, cytochrome P450s, polyketide synthases, and nonribosomal peptide synthetases for cuticle-degradation, detoxification, and toxin biosynthesis that may facilitate its ability to adapt to heterogenous environments. Transcriptional analysis of both fungi during early infection processes provided further insights into the genes and pathways involved in infectivity and specificity. Of particular note, M. acridum transcribed distinct G-protein coupled receptors on cuticles from locusts (the natural hosts) and cockroaches, whereas M. anisopliae transcribed the same receptor on both hosts. This study will facilitate the identification of virulence genes and the development of improved biocontrol strains

A study on biological activity of marine fungi from different habitats in coastal regions.

Science.gov (United States)

Zhou, Songlin; Wang, Min; Feng, Qi; Lin, Yingying; Zhao, Huange

2016-01-01

In recent years, marine fungi have become an important source of active marine natural products. Former researches are limited in habitats selection of fungi with bioactive compounds. In this paper were to measure antibacterial and antitumor cell activity for secondary metabolites of marine fungi, which were isolated from different habitats in coastal regions. 195 strains of marine fungi were isolated and purified from three different habitats. They biologically active experiment results showed that fungi isolation from the mangrove habitats had stronger antibacterial activity than others, and the stains isolated from the estuarial habitats had the least antibacterial activity. However, the strains separated from beach habitats strongly inhibited tumor cell proliferation in vitro, and fungi of mangrove forest habitats had the weakest activity of inhibiting tumor. Meanwhile, 195 fungal strains belonged to 46 families, 84 genera, 142 species and also showed 137 different types of activity combinations by analyzing the inhibitory activity of the metabolites fungi for 4 strains of pathogenic bacteria and B-16 cells. The study investigated the biological activity of marine fungi isolated from different habitats in Haikou coastal regions. The results help us to understand bioactive metabolites of marine fungi from different habitats, and how to selected biological activity fungi from various marine habitats effectively.

Control of grapevine wood fungi in commercial nurseries

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C. Rego

2009-05-01

Full Text Available Previous surveys conducted in commercial nurseries found that different wood fungi, namely Cylindrocarpon spp., Botryosphaeriaceae, Phomopsis viticola and Phaeomoniella chlamydospora infect grapevine cuttings. Two field trials were carried out to evaluate the effectiveness of cyprodinil + fludioxonil, pyraclostrobin + metiram, fludioxonil and cyprodinil to prevent or reduce natural infections caused by such fungi. Rootstock and scion cuttings were soaked in fungicidal suspensions for 50 min prior to grafting. After callusing, the grafted cuttings were planted in two commercial field nurseries with and without a previous history of grapevine cultivation. After nine months in the nursery, the plants were uprooted and analysed for the incidence and severity of the wood fungi. Plants uprooted from the field without a previous history of grapevine cultivation were generally less strongly infected by wood fungi. Under this condition, only the mixture cyprodinil + fludioxonil simultaneously reduced the incidence of Cylindrocarpon and Botryosphaeriaceae fungi, as well as the severity of Cylindrocarpon infections. Treatments did not produce significant differences in the incidence and severity of P. viticola, and Pa. chlamydospora. For plants grown in the field with a grapevine history, all fungicides except cyprodinil significantly reduced the incidence and severity of Cylindrocarpon fungi. Also, the incidence and severity of Botryosphaeriaceae pathogens were significantly decreased both by cyprodinil + fludioxonil and by cyprodinil. No significant differences were noticed for P. viticola incidence and severity, and Pa. chlamydospora was not detected again. These results suggest that the practice of soaking grapevine cuttings in selected fungicides prior to grafting significantly reduces Cylindrocarpon spp. and Botryosphaeriaceae infections, thus improving the quality of planting material.

Secretome of fungus-infected aphids documents high pathogen activity and weak host response

DEFF Research Database (Denmark)

Grell, Morten Nedergaard; Jensen, Annette Bruun; Olsen, Peter B.

2011-01-01

Discovery of novel secretome proteins contributes to the understanding of host-pathogen interactions. Here we report a rich diversity of secreted proteins from the interaction between grain aphids (host, insect order Hemiptera) and fungi of the order Entomophthorales (insect pathogens), made...

Partnerships Between Ambrosia Beetles and Fungi: Lineage-Specific Promiscuity Among Vectors of the Laurel Wilt Pathogen, Raffaelea lauricola.

Science.gov (United States)

Saucedo-Carabez, J R; Ploetz, Randy C; Konkol, J L; Carrillo, D; Gazis, R

2018-04-20

Nutritional mutualisms that ambrosia beetles have with fungi are poorly understood. Although these interactions were initially thought to be specific associations with a primary symbiont, there is increasing evidence that some of these fungi are associated with, and move among, multiple beetle partners. We examined culturable fungi recovered from mycangia of ambrosia beetles associated with trees of Persea humilis (silk bay, one site) and P. americana (avocado, six commercial orchards) that were affected by laurel wilt, an invasive disease caused by a symbiont, Raffaelea lauricola, of an Asian ambrosia beetle, Xyleborus glabratus. Fungi were isolated from 20 adult females of X. glabratus from silk bay and 70 each of Xyleborus affinis, Xyleborus bispinatus, Xyleborus volvulus, Xyleborinus saxesenii, and Xylosandrus crassiusculus from avocado. With partial sequences of ribosomal (LSU and SSU) and nuclear (β-tubulin) genes, one to several operational taxonomic units (OTUs) of fungi were identified in assayed individuals. Distinct populations of fungi were recovered from each of the examined beetle species. Raffaelea lauricola was present in all beetles except X. saxesenii and X. crassiusculus, and Raffaelea spp. predominated in Xyleborus spp. Raffaelea arxii, R. subalba, and R. subfusca were present in more than a single species of Xyleborus, and R. arxii was the most abundant symbiont in both X. affinis and X. volvulus. Raffaelea aguacate was detected for the first time in an ambrosia beetle (X. bispinatus). Yeasts (Ascomycota, Saccharomycotina) were found consistently in the mycangia of the examined beetles, and distinct, putatively co-adapted populations of these fungi were associated with each beetle species. Greater understandings are needed for how mycangia in ambrosia beetles interact with fungi, including yeasts which play currently underresearched roles in these insects.

The cuticle and plant defense to pathogens

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Jean-Pierre eMetraux

2014-06-01

Full Text Available The cuticle provides a physical barrier against water loss and protects against irradiation, xenobiotics and pathogens. Components of the cuticle are perceived by invading fungi and activate developmental processes during pathogenesis. In addition, cuticle alterations of various types induce a syndrome of reactions that often results in resistance to necrotrophs. This article reviews the current knowledge on the role of the cuticle in relation to the perception of pathogens and activation of defenses.

Flexible gateway constructs for functional analyses of genes in plant pathogenic fungi

NARCIS (Netherlands)

Mehrabi, Rahim; Mirzadi Gohari, Amir; Silva, da Gilvan Ferreira; Steinberg, Gero; Kema, Gert H.J.; Wit, de Pierre J.G.M.

2015-01-01

Genetic manipulation of fungi requires quick, low-cost, efficient, high-throughput and molecular tools. In this paper, we report 22 entry constructs as new molecular tools based on the Gateway technology facilitating rapid construction of binary vectors that can be used for functional analysis of

OCULAR ASPECTS OF HYPERTHYROIDISM WITH SPECIAL REFERENCE TO OCULAR MYOPATHY

OpenAIRE

Mallika O. U; Suma Job

2017-01-01

BACKGROUND Hyperthyroidism can result in ocular manifestations even before systemic signs and symptoms develop. It is seen more in females and severe forms are more common in males. Early detection of ocular involvement can prevent vision threatening complications and troublesome discomforts affecting quality of vision. This clinical study highlights the importance of detailed ocular examination in hyperthyroidism. MATERIALS AND METHODS Fifty consecutive patients with ocu...

Spore Acquisition and Survival of Ambrosia Beetles Associated with the Laurel Wilt Pathogen in Avocados after Exposure to Entomopathogenic Fungi.

Science.gov (United States)

Avery, Pasco B; Bojorque, Verónica; Gámez, Cecilia; Duncan, Rita E; Carrillo, Daniel; Cave, Ronald D

2018-04-25

Laurel wilt is a disease threatening the avocado industry in Florida. The causative agent of the disease is a fungus vectored by ambrosia beetles that bore into the trees. Until recently, management strategies for the vectors of the laurel wilt fungus relied solely on chemical control and sanitation practices. Beneficial entomopathogenic fungi (EPF) are the most common and prevalent natural enemies of pathogen vectors. Laboratory experiments demonstrated that commercial strains of EPF can increase the mortality of the primary vector, Xyleborus glabratus , and potential alternative vectors, Xylosandrus crassiusculus , Xyleborus volvulus and Xyleborus bispinatus (Coleoptera: Curculionidae: Scolytinae). Our study provides baseline data for three formulated commercially-available entomopathogenic fungi used as potential biocontrol agents against X. crassiusculus , X. volvulus and X. bispinatus. The specific objectives were to determine: (1) the mean number of viable spores acquired per beetle species adult after being exposed to formulated fungal products containing different strains of EPF ( Isaria fumosorosea , Metarhizium brunneum and Beauveria bassiana ); and (2) the median and mean survival times using paper disk bioassays. Prior to being used in experiments, all fungal suspensions were adjusted to 2.4 × 10⁶ viable spores/mL. The number of spores acquired by X. crassiusculus was significantly higher after exposure to B. bassiana , compared to the other fungal treatments. For X. volvulus , the numbers of spores acquired per beetle were significantly different amongst the different fungal treatments, and the sequence of spore acquisition rates on X. volvulus from highest to lowest was I. fumosorosea > M. brunneum > B. bassiana . After X. bispinatus beetles were exposed to the different suspensions, the rates of acquisition of spores per beetle amongst the different fungal treatments were similar. Survival estimates (data pooled across two tests) indicated an

Ocular lesions and experimental choline deficiency Lesiones oculares y deficiencia experimental de colina

Directory of Open Access Journals (Sweden)

Georgina P. Ossani

2006-10-01

Full Text Available Previous studies have shown ocular haemorrhages in choline-deficient rats. The aim of this paper is to study further the relationship between ocular and renal lesions and biochemical alterations in rats fed a choline-deficient diet. Fifty one weanling male Wistar rats, were divided into two groups. Thirty one of them were fed a choline-deficient diet and the rest was fed a choline-supplemented diet ad libitum. Animals from both groups were killed between the fifth and the eighth day. Urea, creatinine and homocysteine concentrations in blood were determined. Eyes were used for light microscopy study; high resolution light microscopy and the study of the retina as "rétine a plat". Kidneys were studied by light microscopy. Choline-supplemented rats did not show ocular or renal lesion. Choline-deficient rats that showed renal lesions, tubular or cortical necrosis, did not always have ocular changes. There were no ocular changes in the only choline-deficient rat without renal lesion. The ocular changes consisted mainly in haemorrhage in both cameras and ciliary and vitreous bodies. Correlations between ocular and renal lesion (r=0.72, pEstudios previos han demostrado hemorragia ocular en ratas deficientes en colina. El objetivo de este trabajo es profundizar en la relación entre las alteraciones oculares, renales y bioquímicas en ratas deficientes en colina. Cincuenta y una ratas Wistar macho recién destetadas fueron divididas en dos grupos: treinta y una fueron alimentadas con una dieta colino deficiente y el resto con colina suplementada ad-libitum. Los animales de ambos grupos fueron sacrificados entre el quinto y el octavo día. Se midió la concentración de urea, creatinina y homocisteína en sangre. Los ojos fueron estudiados por microscopía de luz, microscopía óptica de alta resolución y para el estudio de la retina como retina plana. Los riñones fueron estudiados por microscopía de luz. Las ratas suplementadas con colina no

Predator-prey interactions of nematode-trapping fungi and nematodes: both sides of the coin.

Science.gov (United States)

Vidal-Diez de Ulzurrun, Guillermo; Hsueh, Yen-Ping

2018-05-01

Nematode-trapping fungi develop complex trapping devices to capture and consume nematodes. The dynamics of these organisms is especially important given the pathogenicity of nematodes and, consequently, the potential application of nematode-trapping fungi as biocontrol agents. Furthermore, both the nematodes and nematode-trapping fungi can be easily grown in laboratories, making them a unique manipulatable predator-prey system to study their coevolution. Several different aspects of these fungi have been studied, such as their genetics and the different factors triggering trap formation. In this review, we use the nematode-trapping fungus Arthrobotrys oligospora (which forms adhesive nets) as a model to describe the trapping process. We divide this process into several stages; namely attraction, recognition, trap formation, adhesion, penetration, and digestion. We summarize the latest findings in the field and current knowledge on the interactions between nematodes and nematode-trapping fungi, representing both sides of the predator-prey interaction.

RNAi suppressors encoded by pathogenic human viruses

NARCIS (Netherlands)

de Vries, Walter; Berkhout, Ben

2008-01-01

RNA silencing or RNAi interference (RNAi) serves as an innate antiviral mechanism in plants, fungi and animals. Human viruses, like plant viruses, encode suppressor proteins or RNAs that block or modulate the RNAi pathway. This review summarizes the mechanisms by which pathogenic human viruses

Community composition of target vs. non-target fungi in fungicide treated wheat

DEFF Research Database (Denmark)

Knorr, Kamilla; Jørgensen, Lise Nistrup; Justesen, Annemarie Fejer

2012-01-01

disease in wheat and within the last decade, new aggressive strains of yellow rust has caused severe epidemics that lead to substantial yield losses. This study explored the community composition of target versus non-target fungi in yellow rust infected wheat as affected by treatment timing and dose......Fungicide treatments are common control strategies used to manage fungal pathogens in agricultural fields, however, effects of treatments on the composition of total fungal communities, including non-target fungi, in the phyllosphere is not well known. Yellow rust (Puccinia striiformis) is a common...

[Diversity and community structure of endophytic fungi from Taxus chinensis var. mairei].

Science.gov (United States)

2014-07-01

A total of 628 endophytic fungi were isolated from 480 tissue segments of needles and branches of Taxus chinensis var. mairei. According to morphological characteristics and ITS sequences, they represented 43 taxa in 28 genera, of which 10 Hyphomycetes, 20 Coelomycetes, 12 Ascomycetes and 1 unknown fungus. Phomopsis mali was confirmed as the dominant species. In accordance with relative frequency, Alternaria alternata, Aureobasidium pullulans, Colletotrichum boninense, C. gloeosporioides, Epicoccum nigrum , Fungal sp., Fusarium lateritium, Glomerella cingulata, Magnaporthales sp. , Nigrospora oryzae, Pestalotiopsis maculiformans, P. microspora, Peyronellaea glomerata and Xylaria sp. 1 were more common in T. chinensis var. mairei. T. chinensis var. mairei were severely infected by endophytic fungi. Endophytic fungi were found in 81 percent of plant tissues with a high diversity. Distribution ranges of endophytic fungi were influenced by tissue properties. The colonization rate, richness, diversity of endophytic fungi in needles were obviously lower than in branches, and kinds of endophytic fungi between branches were more similar than those in needles, thus endophytic fungi had tissue preference. In addition, tissue age influenced the community structure of endophytic fungi. The elder branch tissues were, the higher colonization rate, richness, diversity of endophytic fungi were. Systematic studying the diversity and community structure of endophytic fungi in T. chinensis var. mairei and clarifying their distribution regularity in plant tissues would offer basic data and scientific basis for their development and utilization. Discussing the presence of fungal pathogens in healthy plant tissues would be of positive significance for source protection of T. chinensis var. mairei.

Fungal Diversity in Field Mold-Damaged Soybean Fruits and Pathogenicity Identification Based on High-Throughput rDNA Sequencing

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Jiang Liu

2017-05-01

Full Text Available Continuous rain and an abnormally wet climate during harvest can easily lead to soybean plants being damaged by field mold (FM, which can reduce seed yield and quality. However, to date, the underlying pathogen and its resistance mechanism have remained unclear. The objective of the present study was to investigate the fungal diversity of various soybean varieties and to identify and confirm the FM pathogenic fungi. A total of 62,382 fungal ITS1 sequences clustered into 164 operational taxonomic units (OTUs with 97% sequence similarity; 69 taxa were recovered from the samples by internal transcribed spacer (ITS region sequencing. The fungal community compositions differed among the tested soybeans, with 42 OTUs being amplified from all varieties. The quadratic relationships between fungal diversity and organ-specific mildew indexes were analyzed, confirming that mildew on soybean pods can mitigate FM damage to the seeds. In addition, four potentially pathogenic fungi were isolated from FM-damaged soybean fruits; morphological and molecular identification confirmed these fungi as Aspergillus flavus, A. niger, Fusarium moniliforme, and Penicillium chrysogenum. Further re-inoculation experiments demonstrated that F. moniliforme is dominant among these FM pathogenic fungi. These results lay the foundation for future studies on mitigating or preventing FM damage to soybean.

X-linked ocular albinism in Blacks. Ocular albinism cum pigmento.

Science.gov (United States)

O'Donnell, F E; Green, W R; Fleischman, J A; Hambrick, G W

1978-07-01

X-linked ocular albinism can be an unsuspected cause of congenital nystagmus in blacks. In this study, eight of ten black ocular albinos from two kindreds had nonalbinotic, moderately pigmented fundi and no transillumination of the iris. We refer to this paradoxical condition as "ocular albinism cum pigmento." The only constant ophthalmoscopic feature was a foveal hypoplasia. Biopsy of clinically normal skin to demonstrate giant pigment granules is the most accurate means of diagnosis.

Host-induced aneuploidy and phenotypic diversification in the Sudden Oak Death pathogen Phytophthora ramorum

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Aneuploidy can result in significant phenotypic changes, which can sometimes be selectively advantageous. For example, aneuploidy confers resistance to antifungal drugs in human pathogenic fungi. Aneuploidy has also been observed in invasive fungal and oomycete plant pathogens in the field. Environm...

Evolution and genome architecture in fungal plant pathogens.

Science.gov (United States)

Möller, Mareike; Stukenbrock, Eva H

2017-12-01

The fungal kingdom comprises some of the most devastating plant pathogens. Sequencing the genomes of fungal pathogens has shown a remarkable variability in genome size and architecture. Population genomic data enable us to understand the mechanisms and the history of changes in genome size and adaptive evolution in plant pathogens. Although transposable elements predominantly have negative effects on their host, fungal pathogens provide prominent examples of advantageous associations between rapidly evolving transposable elements and virulence genes that cause variation in virulence phenotypes. By providing homogeneous environments at large regional scales, managed ecosystems, such as modern agriculture, can be conducive for the rapid evolution and dispersal of pathogens. In this Review, we summarize key examples from fungal plant pathogen genomics and discuss evolutionary processes in pathogenic fungi in the context of molecular evolution, population genomics and agriculture.

Fungal endophytes which invade insect galls: insect pathogens, benign saprophytes, or fungal inquilines?

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Wilson, Dennis

1995-08-01

Fungi are frequently found within insect galls. However, the origin of these fungi, whether they are acting as pathogens, saprophytes invading already dead galls, or fungal inquilines which invade the gall but kill the gall maker by indirect means, is rarely investigated. A pathogenic role for these fungi is usually inferred but never tested. I chose the following leaf-galling-insect/host-plant pairs (1) a cynipid which forms two-chambered galls on the veins of Oregon white oak, (2) a cynipid which forms single-chambered galls on California coast live oak, and (3) an aphid which forms galls on narrowleaf cottonwood leaves. All pairs were reported to have fungi associated with dead insects inside the gall. These fungi were cultured and identified. For the two cynipids, all fungi found inside the galls were also present in the leaves as fungal endophytes. The cottonwood leaves examined did not harbor fungal endophytes. For the cynipid on Oregon white oak, the fungal endophyte grows from the leaf into the gall and infects all gall tissue but does not directly kill the gall maker. The insect dies as a result of the gall tissue dying from fungal infection. Therefore, the fungus acts as an inquiline. Approximately 12.5% of these galls die as a result of invasion by the fungal endophyte.

An integrated genomic and transcriptomic survey of mucormycosis-causing fungi

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Chibucos, Marcus C.; Soliman, Sameh; Gebremariam, Teclegiorgis; Lee, Hongkyu; Daugherty, Sean; Orvis, Joshua; Shetty, Amol C.; Crabtree, Jonathan; Hazen, Tracy H.; Etienne, Kizee A.; Kumari, Priti; O'Connor, Timothy D.; Rasko, David A.; Filler, Scott G.; Fraser, Claire M.; Lockhart, Shawn R.; Skory, Christopher D.; Ibrahim, Ashraf S.; Bruno, Vincent M.

2016-01-01

Mucormycosis is a life-threatening infection caused by Mucorales fungi. Here we sequence 30 fungal genomes, and perform transcriptomics with three representative Rhizopus and Mucor strains and with human airway epithelial cells during fungal invasion, to reveal key host and fungal determinants contributing to pathogenesis. Analysis of the host transcriptional response to Mucorales reveals platelet-derived growth factor receptor B (PDGFRB) signaling as part of a core response to divergent pathogenic fungi; inhibition of PDGFRB reduces Mucorales-induced damage to host cells. The unique presence of CotH invasins in all invasive Mucorales, and the correlation between CotH gene copy number and clinical prevalence, are consistent with an important role for these proteins in mucormycosis pathogenesis. Our work provides insight into the evolution of this medically and economically important group of fungi, and identifies several molecular pathways that might be exploited as potential therapeutic targets. PMID:27447865

The Relationship Between Ocular Itch, Ocular Pain, and Dry Eye Symptoms (An American Ophthalmological Society Thesis).

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Galor, Anat; Small, Leslie; Feuer, William; Levitt, Roy C; Sarantopoulos, Konstantinos D; Yosipovitch, Gil

2017-08-01

To evaluate associations between sensations of ocular itch and dry eye (DE) symptoms, including ocular pain, and DE signs. A cross-sectional study of 324 patients seen in the Miami Veterans Affairs eye clinic was performed. The evaluation consisted of questionnaires regarding ocular itch, DE symptoms, descriptors of neuropathic-like ocular pain (NOP), and evoked pain sensitivity testing on the forehead and forearm, followed by a comprehensive ocular surface examination including corneal mechanical sensitivity testing. Analyses were performed to examine for differences between those with and without subjective complaints of ocular itch. The mean age was 62 years with 92% being male. Symptoms of DE and NOP were more frequent in patients with moderate-severe ocular itch compared to those with no or mild ocular itch symptoms. With the exception of ocular surface inflammation (abnormal matrix metalloproteinase 9 testing) which was less common in those with moderate-severe ocular itch symptoms, DE signs were not related to ocular itch. Individuals with moderate-severe ocular itch also demonstrated greater sensitivity to evoked pain on the forearm and had higher non-ocular pain, depression, and post-traumatic stress disorders scores, compared to those with no or mild itch symptoms. Subjects with moderate-severe ocular itch symptoms have more severe symptoms of DE, NOP, non-ocular pain and demonstrate abnormal somatosensory testing in the form of increased sensitivity to evoked pain at a site remote from the eye, consistent with generalized hypersensitivity.

Ocular Sarcoidosis

Science.gov (United States)

Pasadhika, Sirichai; Rosenbaum, James T

2015-01-01

Sarcoidosis is one of the leading causes of inflammatory eye disease. Ocular sarcoidosis can involve any part of the eye and its adnexal tissues, and may cause uveitis, episcleritis/scleritis, eyelid abnormalities, conjunctival granuloma, optic neuropathy, lacrimal gland enlargement and orbital inflammation. Glaucoma and cataract can be complications from inflammation itself or adverse effects from therapy. Ophthalmic manifestations can be isolated, or associated with other organ involvement. Patients with ocular sarcoidosis can present with a wide range of clinical presentations and severity. Multi-disciplinary approaches are required to achieve the best treatment outcomes for both ocular and systemic manifestations. PMID:26593141

The genetic basis of local adaptation for pathogenic fungi in agricultural ecosystems.

Science.gov (United States)

Croll, Daniel; McDonald, Bruce A

2017-04-01

Local adaptation plays a key role in the evolutionary trajectory of host-pathogen interactions. However, the genetic architecture of local adaptation in host-pathogen systems is poorly understood. Fungal plant pathogens in agricultural ecosystems provide highly tractable models to quantify phenotypes and map traits to corresponding genomic loci. The outcome of crop-pathogen interactions is thought to be governed largely by gene-for-gene interactions. However, recent studies showed that virulence can be governed by quantitative trait loci and that many abiotic factors contribute to the outcome of the interaction. After introducing concepts of local adaptation and presenting examples from wild plant pathosystems, we focus this review on a major pathogen of wheat, Zymoseptoria tritici, to show how a multitude of traits can affect local adaptation. Zymoseptoria tritici adapted to different thermal environments across its distribution range, indicating that thermal adaptation may limit effective dispersal to different climates. The application of fungicides led to the rapid evolution of multiple, independent resistant populations. The degree of colony melanization showed strong pleiotropic effects with other traits, including trade-offs with colony growth rates and fungicide sensitivity. The success of the pathogen on its host can be assessed quantitatively by counting pathogen reproductive structures and measuring host damage based on necrotic lesions. Interestingly, these two traits can be weakly correlated and depend both on host and pathogen genotypes. Quantitative trait mapping studies showed that the genetic architecture of locally adapted traits varies from single loci with large effects to many loci with small individual effects. We discuss how local adaptation could hinder or accelerate the development of epidemics in agricultural ecosystems. © 2016 John Wiley & Sons Ltd.

The hydrolytic enzymes produced by fungi strains isolated from the sand and soil of recreational areas

Science.gov (United States)

Kurnatowski, Piotr; Wójcik, Anna; Błaszkowska, Joanna; Góralska, Katarzyna

2016-10-01

The pathogenicity of fungi depends on, inter alia, the secretion of hydrolytic enzymes. The aim of this study was to determine the enzymatic activity of yeasts and yeast-like fungi isolated from children’s recreation areas, and compare the results with literature data of strains obtained from patients with mycoses. The enzymatic activity of 96 strains was assessed using an API ZYM kit (bioMerieux, France) and their biotypes were established. The fungal species were found to produce from 16 to 19 hydrolases: the most active were: leucine arylamidase (e5), acid phosphatase (e10), alkaline phosphatase (e1), naphthol-AS-BI-phosphohydrolase (e11), esterase – C4 (e2), β-galac - tosidase (e13) and β-glucosidase (e16). In addition, 13 biotypes characteristic of particular species of fungi were defined. Most strains could be categorized as biotypes C2 – 39.5% and A – 26%. The examined fungal strains isolated from recreational areas have selected biochemical characteristics i.e. production of hydrolases, which demonstrate their pathogenicity. They produce a number of enzymes which are also present in strains isolated from patients with mycoses, including: leucine arylamidase (e5), acid phosphatase (e10), naphthol-AS-BI-phosphohydrolase (e11) and alkaline phosphatase (e1). The biotypes identified in the course of this study (A, B3, B4, C1, C6 and D3) have been also reported in cases of fungal infection. Therefore, the fungi present in the sand and soil of recreational have pathogenic properties and are possible factors of fungal infection among children.

Thermophillic and thermotolerant fungi isolated from the thermal effluent of nuclear power generating reactors

International Nuclear Information System (INIS)

Rippon, J.W.; Gerhold, R.; Heath, M.

1980-01-01

Over a period of a year, samples of water, foam, microbial mat, soil and air were obtained from areas associated with the cooling canal of a nuclear power station. The seventeen sample sites included water in the cooling canal that was thermally enriched and soil and water adjacent to, up-stream, downstream and at a distance from the generator. Air samples were taken at the plant and at various disstances from the plant. Fifty-two species of thermotolerant and thermophilic fungi were isolated. Of these, eleven species are grouped as opportunistic Mucorales or opportunistic Aspergillus sp. One veterinary pathogen was also isolated (Dactylaria gallopara). The opportunistic/pathogenic fungi were found primarily in the intake bay, the discharge bay and the cooling canal. Smaller numbers were obtained at both upstream and downstream locations. Soil samples near the cooling canal reflected an enrichment of thermophilous organisms, the previously mentioned opportunistic Mucorales and Aspergillus spp. Their numbers were found to be greater than that usually encountered in a mesophilic environment. However, air and soil samples taken at various distances from the power station indicated no greater abundance of these thermophilous fungi than would be expected from a thermal enriched environment. Our results indicate that there was no significant dissemination of thermophilous fungi from the thermal enriched effluents to the adjacent environment. These findings are consistent with the results of other investigators. (orig.)

Mutualism and Antagonism: Ecological Interactions Among Bark Beetles, Mite and Fungi

Science.gov (United States)

K.D. Klepzig; J.C. Moser; M.J. Lombardero; M.P. Ayres; R.W. Hofstetter; C.J. Walkinshaw

2001-01-01

Insect-fungal complexes provide challenging and fascinating systems for the study of biotic interactions between plants. plant pathogens, insect vectors and other associated organisms. The types of interactions among these organisms (mutualism. antagonism. parasitism. phoresy. etc.) are as variable as the range of organisms involved (plants, fungi, insects. mites. etc...

PsAAT3, an oomycete-specific aspartate aminotransferase, is required for full pathogenicity of the oomycete pathogen Phytophthora sojae.

Science.gov (United States)

Wang, Rongbo; Zhang, Meixiang; Liu, Hong; Xu, Jing; Yu, Jia; He, Feng; Zhang, Xiong; Dong, Suomeng; Dou, Daolong

2016-04-01

Pathogen nutrient acquisition and metabolism are critical for successful infection and colonization. However, the nutrient requirements and metabolic pathways related to pathogenesis in oomycete pathogens are unknown. In this study, we bioinformatically identified Phytophthora sojae aspartate aminotransferases (AATs), which are key enzymes that coordinate carbon and nitrogen metabolism. We demonstrated that P. sojae encodes more AATs than the analysed fungi. Some of the AATs contained additional prephenate dehydratase and/or prephenate dehydrogenase domains in their N-termini, which are unique to oomycetes. Silencing of PsAAT3, an infection-inducible expression gene, reduced P. sojae pathogenicity on soybean plants and affected the growth under N-starving condition, suggesting that PsAAT3 is involved in pathogen pathogenicity and nitrogen utilisation during infection. Our results suggest that P. sojae and other oomycete pathogens may have distinct amino acid metabolism pathways and that PsAAT3 is important for its full pathogenicity. Copyright © 2016 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

USE OF SAPROPHYTIC FUNGI SPECIMENS AS A PLANT PROTECTION AGENTS IN TOMATOE PLANTATION

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Katarzyna Bandurska

2015-07-01

Full Text Available The purpose of this study was to determine the effects of the Trichoderma spp. fungi on the conditions and health of tomato plants. The experiments were conducted in pot cultures and controlled conditions. Commercial formula TRIFENDER containing Trichoderma asperellum spores and isolated from garden soil strain T12 Trichoderma viride were used. In one embodiment, the plants were treated with pathogenic strain of Fusarium sp. that commonly damages crops and against which the whole arsenal of chemicals is used. Preparations obtained from isolated and multiplied fungal cultures were used for the treatment of the above-ground (spraying and under-ground (sprinkling parts of tomatoes. Influence of the Trichoderma fungi was determined by comparing the presence of necrosis on leaves in various groups of cultivated tomatoes compared to control samples. The development of seedlings was checked by measuring the length of plants and the weight of fresh and dry plants. The results demonstrated the protective role of Trichoderma spp. fungi in relation to the Fusarium sp.. Leaves of tomato treated with solutions of saprophytic fungi had a statistically significant lower amount of necrotic changes caused by the pathogen. More effective in this regard was uncommercial isolate of T. viride. Formulation used in the experiments Trifender and isolate T. viride statistically significant influence on the growth and development of the tomato plants as evidenced by increased compared to the control fresh and dry weight of plants.

Diverse deep-sea fungi from the South China Sea and their antimicrobial activity.

Science.gov (United States)

Zhang, Xiao-Yong; Zhang, Yun; Xu, Xin-Ya; Qi, Shu-Hua

2013-11-01

We investigated the diversity of fungal communities in nine different deep-sea sediment samples of the South China Sea by culture-dependent methods followed by analysis of fungal internal transcribed spacer (ITS) sequences. Although 14 out of 27 identified species were reported in a previous study, 13 species were isolated from sediments of deep-sea environments for the first report. Moreover, these ITS sequences of six isolates shared 84-92 % similarity with their closest matches in GenBank, which suggested that they might be novel phylotypes of genera Ajellomyces, Podosordaria, Torula, and Xylaria. The antimicrobial activities of these fungal isolates were explored using a double-layer technique. A relatively high proportion (56 %) of fungal isolates exhibited antimicrobial activity against at least one pathogenic bacterium or fungus among four marine pathogenic microbes (Micrococcus luteus, Pseudoaltermonas piscida, Aspergerillus versicolor, and A. sydowii). Out of these antimicrobial fungi, the genera Arthrinium, Aspergillus, and Penicillium exhibited antibacterial and antifungal activities, while genus Aureobasidium displayed only antibacterial activity, and genera Acremonium, Cladosporium, Geomyces, and Phaeosphaeriopsis displayed only antifungal activity. To our knowledge, this is the first report to investigate the diversity and antimicrobial activity of culturable deep-sea-derived fungi in the South China Sea. These results suggest that diverse deep-sea fungi from the South China Sea are a potential source for antibiotics' discovery and further increase the pool of fungi available for natural bioactive product screening.

When green and red mycology meet: Impressions from an interdisciplinary forum on virulence mechanisms of phyto- and human-pathogenic fungi.

Science.gov (United States)

Yu, Yidong; Hube, Bernhard; Kämper, Jörg; Meyer, Vera; Krappmann, Sven

2017-10-03

Fungal infections pose a constant threat to plants and humans, but detailed knowledge about pathogenesis, immunity, or virulence is rather scarce. Due to the fact that a certain overlap in the armoury of infection exists between plant- and human-pathogenic fungi, an interdisciplinary forum was held in October 2016 at the Institute for Clinical Microbiology, Immunology and Hygiene in Erlangen under the organisational umbrella from two special interest groups of German microbial societies. Scientific exchange and intense discussion of this timely topic was fostered by bringing together renowned experts in their respective fields to present their thoughts and recent findings in the course of a plenary lecture and six themed sessions, accompanied by oral and poster contributions of young researchers. By targeting the topic of fungal virulence mechanisms from various angles and in the context of plant and human hosts, some common grounds and exciting perspectives could be deduced during this vibrant scientific event.

Miopatia ocular descendente

Directory of Open Access Journals (Sweden)

Marcos R. G. de Freitas

1975-06-01

Full Text Available Os autores apresentam caso de paciente jovem, do sexo feminino, com afecção muscular primária ocular e faríngea sem caráter familial. Foram feitos estudos eletromiográficos e histopatológicos musculares que confirmam o caráter miogênico do processo. É feita comparação entre a miopatia ocular e a miopatia ocular descendente, acreditando os autores que seriam variantes

Diversity and antibacterial activities of fungi derived from the Gorgonian Echinogorgia rebekka from the South China Sea.

Science.gov (United States)

Wang, Ya-Nan; Shao, Chang-Lun; Zheng, Cai-Juan; Chen, Yi-Yan; Wang, Chang-Yun

2011-01-01

The diversity of symbiotic fungi associated with the gorgonian coral Echinogorgia rebekka from the Weizhou coral reef in the South China Sea was investigated. Combined with morphologic traits, ITS-rDNA sequences revealed 18 fungal strains from this gorgonian. All of the 18 fungi belonged to the phylum Ascomycota and were distributed among seven genera in five orders: Eurotiales (Aspergillus and Penicillium), Pleosporales (Alternaria), Capnodiales (Cladosporium), Trichosphaeriales (Nigrospora) and Hypocreales (Hypocrea and Nectria). Antibacterial activities of these fungal strains were investigated with five pathogenic bacteria. All of the 18 fungal strains displayed different levels of antibacterial activities, most of which exhibited moderate to high antibacterial activities to the Gram-positive pathogens Staphylococcus aureus and Micrococcus tetragenus, and showed relatively low bioactivities to other three pathogenic bacteria. Several fungal strains in the genera Penicillium and Cladosporium with strong antibacterial activities provide potential for further research on isolation of bioactive secondary metabolites.

Cotton plants export microRNAs to inhibit virulence gene expression in a fungal pathogen.

Science.gov (United States)

Zhang, Tao; Zhao, Yun-Long; Zhao, Jian-Hua; Wang, Sheng; Jin, Yun; Chen, Zhong-Qi; Fang, Yuan-Yuan; Hua, Chen-Lei; Ding, Shou-Wei; Guo, Hui-Shan

2016-09-26

Plant pathogenic fungi represent the largest group of disease-causing agents on crop plants, and are a constant and major threat to agriculture worldwide. Recent studies have shown that engineered production of RNA interference (RNAi)-inducing dsRNA in host plants can trigger specific fungal gene silencing and confer resistance to fungal pathogens 1-7 . Although these findings illustrate efficient uptake of host RNAi triggers by pathogenic fungi, it is unknown whether or not such an uptake mechanism has been evolved for a natural biological function in fungus-host interactions. Here, we show that in response to infection with Verticillium dahliae (a vascular fungal pathogen responsible for devastating wilt diseases in many crops) cotton plants increase production of microRNA 166 (miR166) and miR159 and export both to the fungal hyphae for specific silencing. We found that two V. dahliae genes encoding a Ca 2+ -dependent cysteine protease (Clp-1) and an isotrichodermin C-15 hydroxylase (HiC-15), and targeted by miR166 and miR159, respectively, are both essential for fungal virulence. Notably, V. dahliae strains expressing either Clp-1 or HiC-15 rendered resistant to the respective miRNA exhibited drastically enhanced virulence in cotton plants. Together, our findings identify a novel defence strategy of host plants by exporting specific miRNAs to induce cross-kingdom gene silencing in pathogenic fungi and confer disease resistance.

Development of a Selective Medium for the Fungal Pathogen Fusarium graminearum Using Toxoflavin Produced by the Bacterial Pathogen Burkholderia glumae

Directory of Open Access Journals (Sweden)

Boknam Jung

2013-12-01

Full Text Available The ascomycete fungus Fusarium graminearum is a major causal agent for Fusarium head blight in cereals and produces mycotoxins such as trichothecenes and zearalenone. Isolation of the fungal strains from air or cereals can be hampered by various other airborne fungal pathogens and saprophytic fungi. In this study, we developed a selective medium specific to F. graminearum using toxoflavin produced by the bacterial pathogen Burkholderia glumae. F. graminearum was resistant to toxoflavin, while other fungi were sensitive to this toxin. Supplementing toxoflavin into medium enhanced the isolation of F. graminearum from rice grains by suppressing the growth of saprophytic fungal species. In addition, a medium with or without toxoflavin exposed to wheat fields for 1 h had 84% or 25%, respectively, of colonies identified as F. graminearum. This selection medium provides an efficient tool for isolating F. graminearum, and can be adopted by research groups working on genetics and disease forecasting.

Systematic analysis of ocular trauma by a new proposed ocular trauma classification

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Bhartendu Shukla

2017-01-01

Full Text Available Purpose: The current classification of ocular trauma does not incorporate adnexal trauma, injuries that are attributable to a nonmechanical cause and destructive globe injuries. This study proposes a new classification system of ocular trauma which is broader-based to allow for the classification of a wider range of ocular injuries not covered by the current classification. Methods: A clinic-based cross-sectional study to validate the proposed classification. We analyzed 535 cases of ocular injury from January 1, 2012 to February 28, 2012 over a 4-year period in an eye hospital in central India using our proposed classification system and compared it with conventional classification. Results: The new classification system allowed for classification of all 535 cases of ocular injury. The conventional classification was only able to classify 364 of the 535 trauma cases. Injuries involving the adnexa, nonmechanical injuries and destructive globe injuries could not be classified by the conventional classification, thus missing about 33% of cases. Conclusions: Our classification system shows an improvement over existing ocular trauma classification as it allows for the classification of all type of ocular injuries and will allow for better and specific prognostication. This system has the potential to aid communication between physicians and result in better patient care. It can also provide a more authentic, wide spectrum of ocular injuries in correlation with etiology. By including adnexal injuries and nonmechanical injuries, we have been able to classify all 535 cases of trauma. Otherwise, about 30% of cases would have been excluded from the study.

Ocular Straylight

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Sigrid Mueller-Schotte OD, MSc

2015-10-01

Full Text Available Intra-ocular straylight can cause decreased visual functioning, and it may cause diminished vision-related quality of life (VRQOL. This cross-sectional population-based study investigates the association between straylight and VRQOL in middle-aged and elderly individuals. Multivariable linear regression analyses were used to assess the association between straylight modeled continuously and cutoff at the recommended fitness-to-drive value, straylight ≥ 1.4 log(s, and VRQOL. The study showed that participants with normal straylight values, straylight ≤ 1.4 log(s, rated their VRQOL slightly better than those with high straylight values (straylight ≥ 1.4 log(s. Furthermore, multivariable regression analysis revealed a borderline statistical significant association ( p = .06 between intra-ocular straylight and self-reported VRQOL in middle-aged and elderly individuals. The association between straylight and self-reported VRQOL was not influenced by the status of the intra-ocular lens (natural vs. artificial intra-ocular lens after cataract extraction or the number of (instrumental activities of daily living that were reported as difficult for the elderly individuals.

Comparative Genomics of Smut Pathogens: Insights From Orphans and Positively Selected Genes Into Host Specialization

NARCIS (Netherlands)

Benevenuto, J.; Texeira-Silva, N.S.; Kuramae, E.E.; Croll, D.; Vitorello, C.B.M.

2018-01-01

Host specialization is a key evolutionary process for the diversification and emergence of new pathogens. However, the molecular determinants of host range are poorly understood. Smut fungi are biotrophic pathogens that have distinct and narrow host ranges based on largely unknown genetic

Isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings.

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Soltani, Maryam; Bayat, Mansour; Hashemi, Seyed J; Zia, Mohammadali; Pestechian, Nader

2013-01-01

Invasive fungal infections cause considerable morbidity and mortality in immunocompromised hosts. Pigeon droppings could especially be a potential carrier in the spread of pathogenic yeasts and mold fungi into the environment. The objective of this study was to isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings. One hundred twenty samples of pigeon droppings were suspended 1:10 in saline solution and then cultured. Identification of C. neoformans was performed on bird seed agar, presence of a capsule on India ink preparation, urease production on urea agar medium and RapID yeast plus system. The identification of candida species was based on micro-morphological analysis on corn meal-Tween 80 agar, RapID yeast plus system and growth in CHROMagar candida. The identification of other fungi was based on macromorphologic, microscopic, biochemical and physiological characteristics. The highest frequency of yeasts and mold fungi were observed in Candida albicans 6.6% and Penicillium spp. 25%. The frequency rate of C. neoformans isolation was 2.5%. Several types of fungi are present in pigeon droppings that can spread in environment and transmit to children and elderly as well as immunocompromised patients who are at increased risk of contracting opportunistic diseases.

Isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings

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Maryam Soltani

2013-01-01

Full Text Available Background: Invasive fungal infections cause considerable morbidity and mortality in immunocompromised hosts. Pigeon droppings could especially be a potential carrier in the spread of pathogenic yeasts and mold fungi into the environment. The objective of this study was to isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings. Materials and Methods: One hundred twenty samples of pigeon droppings were suspended 1:10 in saline solution and then cultured. Identification of C. neoformans was performed on bird seed agar, presence of a capsule on India ink preparation, urease production on urea agar medium and RapID yeast plus system. The identification of candida species was based on micro-morphological analysis on corn meal-Tween 80 agar, RapID yeast plus system and growth in CHROMagar candida. The identification of other fungi was based on macromorphologic, microscopic, biochemical and physiological characteristics. Results: The highest frequency of yeasts and mold fungi were observed in Candida albicans 6.6% and Penicillium spp. 25%. The frequency rate of C. neoformans isolation was 2.5%. Conclusion: Several types of fungi are present in pigeon droppings that can spread in environment and transmit to children and elderly as well as immunocompromised patients who are at increased risk of contracting opportunistic diseases.

The Hierarchy of Proinflammatory Cytokines in Ocular Inflammation.

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Da Cunha, A P; Zhang, Q; Prentiss, M; Wu, X Q; Kainz, V; Xu, Y Y; Vrouvlianis, J; Li, H; Rangaswamy, N; Leehy, B; McGee, T L; Bell, C L; Bigelow, C E; Kansara, V; Medley, Q; Huang, Q; Wu, H Y

2018-04-01

The concept of tissue-dependent cytokine hierarchy has been demonstrated in a number of diseases, but it has not been investigated in ophthalmic diseases. Here, we evaluated the functional hierarchy of interleukin-1β (IL-1β), IL-6, IL-17A, and tumor necrosis factor (TNF) in the induction of ocular inflammation. We delivered adeno-associated virus (AAV) vectors expressing IL-1β, IL-6, IL-17A, or TNF intravitreally in naïve C57/BL6 mice and compared and contrasted the inflammatory effects in the eye 5 weeks after AAV-mediated gene transfer. We also used an in vitro human system to test the effect of cytokines on barrier function. We found that IL-1β had the highest ability to initiate ocular inflammation. The continuous overexpression of IL-1β resulted in a significant upregulation of additional proinflammatory mediators in the eye. Using scanning laser ophthalmoscope and optical coherence tomography imaging techniques, we showed that a low dose of AAVIL-1β was sufficient and was as pathogenic as a high dose of TNF in inducing vascular leakage, retinal degeneration, and cellular infiltration. Furthermore, only a marginal increase in IL-1β was enough to cause cellular infiltration, thus confirming the highly pathogenic nature of IL-1β in the eye. Contrary to our expectation, IL-6 or IL-17A had minimal or no effect in the eye. To examine the clinical relevance of our findings, we used an impedance assay to show that IL-1β alone or TNF alone was able to cause primary human retinal endothelial cell barrier dysfunction in vitro. Again, IL-6 alone or IL-17A alone had no effect on barrier function; however, in the presence of IL-1β or TNF, IL-17A but not IL-6 may provide additive proinflammatory effects. Our studies demonstrate the existence of a functional hierarchy of proinflammatory cytokines in the eye, and we show that IL-1β is the most pathogenic when it is continuously expressed in the eye.

Nutrient acquisition and secondary metabolites in plant pathogenic fungi

DEFF Research Database (Denmark)

Droce, Aida

Fusarium graminearum is a necrotrophic plant pathogen that leads to severe infections of cereals contaminating them with mycotoxins harmful to human and animal. Blumeria graminis f. sp. hordei is an obligate biotroph that causes powdery mildew infections of barley. In this thesis, lifecycles and ...

Comparative genomic analysis of human fungal pathogens causing paracoccidioidomycosis.

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Christopher A Desjardins

2011-10-01

Full Text Available Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18 and one strain of Paracoccidioides lutzii (Pb01. These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic

Spore Acquisition and Survival of Ambrosia Beetles Associated with the Laurel Wilt Pathogen in Avocados after Exposure to Entomopathogenic Fungi

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Pasco B. Avery

2018-04-01

Full Text Available Laurel wilt is a disease threatening the avocado industry in Florida. The causative agent of the disease is a fungus vectored by ambrosia beetles that bore into the trees. Until recently, management strategies for the vectors of the laurel wilt fungus relied solely on chemical control and sanitation practices. Beneficial entomopathogenic fungi (EPF are the most common and prevalent natural enemies of pathogen vectors. Laboratory experiments demonstrated that commercial strains of EPF can increase the mortality of the primary vector, Xyleborus glabratus, and potential alternative vectors, Xylosandrus crassiusculus, Xyleborus volvulus and Xyleborus bispinatus (Coleoptera: Curculionidae: Scolytinae. Our study provides baseline data for three formulated commercially-available entomopathogenic fungi used as potential biocontrol agents against X. crassiusculus, X. volvulus and X. bispinatus. The specific objectives were to determine: (1 the mean number of viable spores acquired per beetle species adult after being exposed to formulated fungal products containing different strains of EPF (Isaria fumosorosea, Metarhizium brunneum and Beauveria bassiana; and (2 the median and mean survival times using paper disk bioassays. Prior to being used in experiments, all fungal suspensions were adjusted to 2.4 × 106 viable spores/mL. The number of spores acquired by X. crassiusculus was significantly higher after exposure to B. bassiana, compared to the other fungal treatments. For X. volvulus, the numbers of spores acquired per beetle were significantly different amongst the different fungal treatments, and the sequence of spore acquisition rates on X. volvulus from highest to lowest was I. fumosorosea > M. brunneum > B. bassiana. After X. bispinatus beetles were exposed to the different suspensions, the rates of acquisition of spores per beetle amongst the different fungal treatments were similar. Survival estimates (data pooled across two tests indicated an

Molecular signatures of nicotinoid-pathogen synergy in the termite gut.

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Ruchira Sen

Full Text Available Previous studies in lower termites revealed unexpected synergies between nicotinoid insecticides and fungal entomopathogens. The present study investigated molecular mechanisms of nicotinoid-pathogen synergy in the lower termite Reticulitermes flavipes, using the nicotinoid, imidacloprid, in combination with fungal and bacterial entomopathogens. Particular focus was placed on metatranscriptome composition and microbial dynamics in the symbiont-rich termite gut, which houses diverse mixes of protists and bacteria. cDNA microarrays containing a mix of host and protist symbiont oligonucleotides were used to simultaneously assess termite and protist gene expression. Five treatments were compared that included single challenges with sublethal doses of fungi (Metharizium anisopliae, bacteria (Serratia marcescens or imidacloprid, and dual challenges with fungi + imidacloprid or bacteria + imidacloprid. Our findings point towards protist dysbiosis and compromised social behavior, rather than suppression of stereotypical immune defense mechanisms, as the dominant factors underlying nicotinoid-pathogen synergy in termites. Also, greater impacts observed for the fungal pathogen than for the bacterial pathogen suggest that the rich bacterial symbiont community in the R. flavipes gut (>5000 species-level phylotypes exists in an ecological balance that effectively excludes exogenous bacterial pathogens. These findings significantly advance our understanding of antimicrobial defenses in this important eusocial insect group, as well as provide novel insights into how nicotinoids can exert deleterious effects on social insect colonies.

Introduction of Non-Native Pollinators Can Lead to Trans-Continental Movement of Bee-Associated Fungi.

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Shannon M Hedtke

Full Text Available Bees are essential pollinators for many flowering plants, including agriculturally important crops such as apple. As geographic ranges of bees or their host plants change as a result of human activities, we need to identify pathogens that could be transmitted among newly sympatric species to evaluate and anticipate their effects on bee communities. We used PCR screening and DNA sequencing to evaluate exposure to potentially disease-causing microorganisms in a pollinator of apple, the horned mason bee (Osmia cornifrons. We did not detect microsporidia, Wolbachia, or trypanosomes, which are common pathogens of bees, in any of the hundreds of mason bees screened. We did detect both pathogenic and apathogenic (saprophytic fungal species in the genus Ascosphaera (chalkbrood, an unidentified species of Aspergillus fungus, and a strain of bacteria in the genus Paenibacillus that is probably apathogenic. We detected pathogenic fungal strains in asymptomatic adult bees that therefore may be carriers of disease. We demonstrate that fungi from the genus Ascosphaera have been transported to North America along with the bee from its native range in Japan, and that O. cornifrons is exposed to fungi previously only identified from nests of other related bee species. Further study will be required to quantify pathogenicity and health effects of these different microbial species on O. cornifrons and on closely-related native North American mason bees that may now be exposed to novel pathogens. A global perspective is required for pathogen research as geographic ranges of insects and microorganisms shift due to intentional or accidental introductions.

Introduction of Non-Native Pollinators Can Lead to Trans-Continental Movement of Bee-Associated Fungi.

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Hedtke, Shannon M; Blitzer, Eleanor J; Montgomery, Graham A; Danforth, Bryan N

2015-01-01

Bees are essential pollinators for many flowering plants, including agriculturally important crops such as apple. As geographic ranges of bees or their host plants change as a result of human activities, we need to identify pathogens that could be transmitted among newly sympatric species to evaluate and anticipate their effects on bee communities. We used PCR screening and DNA sequencing to evaluate exposure to potentially disease-causing microorganisms in a pollinator of apple, the horned mason bee (Osmia cornifrons). We did not detect microsporidia, Wolbachia, or trypanosomes, which are common pathogens of bees, in any of the hundreds of mason bees screened. We did detect both pathogenic and apathogenic (saprophytic) fungal species in the genus Ascosphaera (chalkbrood), an unidentified species of Aspergillus fungus, and a strain of bacteria in the genus Paenibacillus that is probably apathogenic. We detected pathogenic fungal strains in asymptomatic adult bees that therefore may be carriers of disease. We demonstrate that fungi from the genus Ascosphaera have been transported to North America along with the bee from its native range in Japan, and that O. cornifrons is exposed to fungi previously only identified from nests of other related bee species. Further study will be required to quantify pathogenicity and health effects of these different microbial species on O. cornifrons and on closely-related native North American mason bees that may now be exposed to novel pathogens. A global perspective is required for pathogen research as geographic ranges of insects and microorganisms shift due to intentional or accidental introductions.

Diverse Lifestyles and Strategies of Plant Pathogenesis Encoded in the Genomes of Eighteen Doethideomycetes Fungi

Energy Technology Data Exchange (ETDEWEB)

Ohm, Robin A.; Feau, Nicolas; Henrissat, Bernard; Schoch, Conrad L.; Horwitz, Benjamin A.; Barry, Kerrie W.; Condon, Bradford J.; Copeland, Alex C.; Dhillon, Braham; Glaser, Fabien; Hesse, Cedar N.; Kosti, Idit; LaButti, Kurt; Lindquist, Erika A.; Lucas, Susan; Salamov, Asaf A.; Bradshaw, Rosie E.; Ciuffetti, Lynda; Hamelin, Richard C.; Kema, Gert H. J.; Lawrence, Christopher; Scott, James A.; Spatafora, Joseph W.; Turgeon, B. Gillian; de Wit, Pierre J. G. M.; Zhong, Shaobin; Goodwin, Stephen B.; Grigoriev, Igor V.

2012-03-13

The class of Dothideomycetes is one of the largest and most diverse groups of fungi. Many are plant pathogens and pose a serious threat to agricultural crops grown for biofuel, food or feed. Most Dothideomycetes have only a single host and related species can have very diverse host plants. Eighteen genomes of Dothideomycetes have currently been sequenced by the Joint Genome Institute and other sequencing centers. Here we describe the results of comparative analyses of the fungi in this group.

Ecological plasticity of Trichoderma fungi in leached chernozem

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Svistova, I. D.; Senchakova, T. Yu.

2010-03-01

The autecological properties of Trichoderma fungi ecotypes isolated from the leached chernozem of the forest-steppe zone of the European part of Russia have been studied. We were the first who carried out the complex study of the synecological relations of micromycetes of such kinds in a system including the soil, microbial community, and plants, i.e., their relations with soil saprotrophic fungi, bacteria, actinomycetes, plants, and pathogenic fungi. It was shown that the ecological plasticity of the Trichoderma genus in the soil of this zone is determined by its growth rate, the optimum pH and temperature, the biosynthesis of extracellular hydrolytic enzymes, the biological action of mycotoxins, and the ability for parasitism. The efficiency of the introduction of Trichoderma species typical and atypical for the leached chernozem into this soil and their influence on the structure of the microbial community were evaluated. The T. pseudokoningii ecotype, which produces cellulolytic enzymes, is very promising for industrial biotechnology, and the T. harzianum ecotype can be used in soil biotechnology for the biocontrol of chernozem. The addition of a commercial trichodermin preparation into the chernozem damages the structure of its microbial community.

Infection of Drosophila suzukii with the obligate insect-pathogenic fungus Entomophthora muscae

DEFF Research Database (Denmark)

Becher, Paul G.; Jensen, Rasmus E.; Natsopoulou, Myrsini E.

2018-01-01

Physiological constraints restrict specialist pathogens from infecting new hosts. From an applied perspective, a narrow host range makes specialist pathogens interesting for targeting specific pest insects since they have minimal direct effects on non-target species. Entomopathogenic fungi of the...

The effect of chitosan on limitation of growth and development of some pathogenic fungi for ornamental plants

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Alicja Saniewska

2013-12-01

Full Text Available The inhibitory effect of crab-shell chitosan, medium (200-800 cps and high molecular weight ( 800-2000 cps (purchased from Sigma-Aldrich Chemicals toward Alternaria alternata, Botrytis tulipae, Fiisarium oxysporum f. sp. callistephi, Fusarium oxysporum f. sp. tulipae, Phoma narcissi and Phoma poolensis was evaluated in vitro and in vivo. The chitosan evidently inhibited in vitro growth of all tested pathogens, with a marked effect at higher concentrations above 200 μg/cm3. Chitosan at a concentration of 1,25; 2,5 and 5,0 mg/cm3 didn't have inhibitory action in appearance of fungi growth on naturally contaminated Callistephus chinensis seeds. At the same concentrations, chitosan applied as bulb scales dressing of Hymenocallis narcissiflora bulbs, before inoculation or after inoculation with Phoma narcissi, inhibited the development of necrotic spots on scales. Chitosan used preventively or curatively at a concentrations of 1,25; 2,5 and 5,0 mg/cm3 indicated inhibitory effect on development of Fusarium oxysporum f. sp. tulipae on tulip bulbs. Chitosan at a concentration of 10 mg/cm3 applied preventively (first spray 12th June was very effective in the control of Puccinia antirrhini on snapdragon in the field. The strongest inhibitory effect was observed on snapdragon treated 8 times at week intervals.

Interactions of Heterodera glycines, Macrophomina phaseolina, and Mycorrhizal Fungi on Soybean in Kansas.

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Winkler, H E; Hetrick, B A; Todd, T C

1994-12-01

The impact of naturally occurring arbuscular mycorrhizal fungi on soybean growth and their interaction with Heterodera glycines were evaluated in nematode-infested and uninfested fields in Kansas. Ten soybean cultivars from Maturity Groups III-V with differential susceptibility to H. glycines were treated with the fungicide benomyl to suppress colonization by naturally occurring mycorrhizal fungi and compared with untreated control plots. In H. glycines-infested soil, susceptible cultivars exhibited 39% lower yields, 28% lower colonization by mycorrhizal fungi, and an eightfold increase in colonization by the charcoal rot fungus, Macrophomina phaseolina, compared with resistant cultivars. In the absence of the nematode, susceptible cultivars exhibited 10% lower yields than resistant cultivars, root colonization of resistant vs. susceptible soybean by mycorrhizal fungi varied with sampling date, and there were no differences in colonization by M. phaseolina between resistant and susceptible cultivars. Benomyl application resulted in 19% greater root growth and 9% higher seed yields in H. glycines-infested soil, but did not affect soybean growth and yield in the absence of the nematode. Colonization of soybean roots by mycorrhizal fungi was negatively correlated with H. glycines population densities due to nematode antagonism to the mycorrhizal fungi rather than suppression of nematode populations. Soybean yields were a function of the pathogenic effects of H. glycines and M. phaseolina, and, to a lesser degree, the stimulatory effects of mycorrhizal fungi.

Diversity and Antibacterial Activities of Fungi Derived from the Gorgonian Echinogorgia rebekka from the South China Sea

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Chang-Yun Wang

2011-08-01

Full Text Available The diversity of symbiotic fungi associated with the gorgonian coral Echinogorgia rebekka from the Weizhou coral reef in the South China Sea was investigated. Combined with morphologic traits, ITS-rDNA sequences revealed 18 fungal strains from this gorgonian. All of the 18 fungi belonged to the phylum Ascomycota and were distributed among seven genera in five orders: Eurotiales (Aspergillus and Penicillium, Pleosporales (Alternaria, Capnodiales (Cladosporium, Trichosphaeriales (Nigrospora and Hypocreales (Hypocrea and Nectria. Antibacterial activities of these fungal strains were investigated with five pathogenic bacteria. All of the 18 fungal strains displayed different levels of antibacterial activities, most of which exhibited moderate to high antibacterial activities to the Gram-positive pathogens Staphylococcus aureus and Micrococcus tetragenus, and showed relatively low bioactivities to other three pathogenic bacteria. Several fungal strains in the genera Penicillium and Cladosporium with strong antibacterial activities provide potential for further research on isolation of bioactive secondary metabolites.

Biodiversity, Phylogeny, and Antifungal Functions of Endophytic Fungi Associated with Zanthoxylum bungeanum

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Peiqin Li

2016-09-01

Full Text Available This study investigated the biodiversity, phylogeny, and antifungal activity of endophytic fungi isolated from Zanthoxylum bungeanum. A total of 940 isolates obtained were grouped into 93 morphotypes, 43 species, and 23 genera, which were authenticated by molecular identification based on rDNA internal transcribed spacer (ITS sequence analysis. A high diversity of endophytic fungi from Z. bungeanum are observed with high species richness S (43, Margalef index D′ (6.1351, Shannon–Wiener index H′ (3.2743, Simpson diversity index Ds (0.9476, PIE index (0.9486, and evenness Pielou index J (0.8705 but a low dominant index λ (0.0524. Significant tissue specificity of the endophytic fungi was observed in Z. bungeanum, and the highest species richness and diversity indexes were obtained in the stem. Phylogenetic analyses of the 93 endophytic isolates were carried out by the neighbor-joining (NJ method to demonstrate their evolutionary processes. Antifungal activities of endophytic fungi were assayed and eight endophytic isolates showed strong and long-lasting inhibition against host pathogenic fungi Fusarium sambucinum and Pseudocercospora zanthoxyli. Here, for the first time, we systematically demonstrate the biodiversity, phylogeny, and antifungal activity of endophytic fungi associated with Z. bungeanum and reveal the value of sampling different tissues of a given plant to obtain the greatest endophyte species diversity, which might offer a framework for further investigation and utilization of endophytic fungi as aunique source of interesting and useful bioactive compounds.

A network approach to predict pathogenic genes for Fusarium graminearum.

Science.gov (United States)

Liu, Xiaoping; Tang, Wei-Hua; Zhao, Xing-Ming; Chen, Luonan

2010-10-04

Fusarium graminearum is the pathogenic agent of Fusarium head blight (FHB), which is a destructive disease on wheat and barley, thereby causing huge economic loss and health problems to human by contaminating foods. Identifying pathogenic genes can shed light on pathogenesis underlying the interaction between F. graminearum and its plant host. However, it is difficult to detect pathogenic genes for this destructive pathogen by time-consuming and expensive molecular biological experiments in lab. On the other hand, computational methods provide an alternative way to solve this problem. Since pathogenesis is a complicated procedure that involves complex regulations and interactions, the molecular interaction network of F. graminearum can give clues to potential pathogenic genes. Furthermore, the gene expression data of F. graminearum before and after its invasion into plant host can also provide useful information. In this paper, a novel systems biology approach is presented to predict pathogenic genes of F. graminearum based on molecular interaction network and gene expression data. With a small number of known pathogenic genes as seed genes, a subnetwork that consists of potential pathogenic genes is identified from the protein-protein interaction network (PPIN) of F. graminearum, where the genes in the subnetwork are further required to be differentially expressed before and after the invasion of the pathogenic fungus. Therefore, the candidate genes in the subnetwork are expected to be involved in the same biological processes as seed genes, which imply that they are potential pathogenic genes. The prediction results show that most of the pathogenic genes of F. graminearum are enriched in two important signal transduction pathways, including G protein coupled receptor pathway and MAPK signaling pathway, which are known related to pathogenesis in other fungi. In addition, several pathogenic genes predicted by our method are verified in other pathogenic fungi, which

A network approach to predict pathogenic genes for Fusarium graminearum.

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Xiaoping Liu

Full Text Available Fusarium graminearum is the pathogenic agent of Fusarium head blight (FHB, which is a destructive disease on wheat and barley, thereby causing huge economic loss and health problems to human by contaminating foods. Identifying pathogenic genes can shed light on pathogenesis underlying the interaction between F. graminearum and its plant host. However, it is difficult to detect pathogenic genes for this destructive pathogen by time-consuming and expensive molecular biological experiments in lab. On the other hand, computational methods provide an alternative way to solve this problem. Since pathogenesis is a complicated procedure that involves complex regulations and interactions, the molecular interaction network of F. graminearum can give clues to potential pathogenic genes. Furthermore, the gene expression data of F. graminearum before and after its invasion into plant host can also provide useful information. In this paper, a novel systems biology approach is presented to predict pathogenic genes of F. graminearum based on molecular interaction network and gene expression data. With a small number of known pathogenic genes as seed genes, a subnetwork that consists of potential pathogenic genes is identified from the protein-protein interaction network (PPIN of F. graminearum, where the genes in the subnetwork are further required to be differentially expressed before and after the invasion of the pathogenic fungus. Therefore, the candidate genes in the subnetwork are expected to be involved in the same biological processes as seed genes, which imply that they are potential pathogenic genes. The prediction results show that most of the pathogenic genes of F. graminearum are enriched in two important signal transduction pathways, including G protein coupled receptor pathway and MAPK signaling pathway, which are known related to pathogenesis in other fungi. In addition, several pathogenic genes predicted by our method are verified in other

Tumor ocular metastásico Metastatic ocular tumor

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Martha G Domínguez Expósito

2004-06-01

Full Text Available El carcinoma metastásico del ojo es considerado la neoplasia maligna que más frecuente se encuentra de forma intraocular. Solo cerca del 10 % de las personas que tienen una o más lesiones metastásicas intraoculares son detectadas clínicamente antes de la muerte. A menudo, el carcinoma metastásico ocular es diagnosticado por el oftalmólogo ante la presencia de síntomas oculares. Las lesiones están localizadas con preferencia en coroides. Nos motivo a realizar la presentación de este caso la presencia de lesiones intraoculares múltiples tumorales metastásicos en un paciente cuyo síntoma de presentación fue la disminución de la agudeza visualThe eye metastatic carcinoma is considered the most frequently found intraocular malignant neoplasia. Only 10 % of the persons with one or more metastatic intraocular injuries are clinically detected before death. The metastatic ocular carcinoma is often diagnosed by the ophthalmologist in the presence of ocular symptoms. The injuries are preferably located in the choroid. The appearance of multiple metastatic intraaocular tumoral injuries in a patient whose chief complaint was the reduction of visual acuity motivated us to presente this case

Genome-Enhanced Detection and Identification (GEDI of plant pathogens

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Nicolas Feau

2018-02-01

Full Text Available Plant diseases caused by fungi and Oomycetes represent worldwide threats to crops and forest ecosystems. Effective prevention and appropriate management of emerging diseases rely on rapid detection and identification of the causal pathogens. The increase in genomic resources makes it possible to generate novel genome-enhanced DNA detection assays that can exploit whole genomes to discover candidate genes for pathogen detection. A pipeline was developed to identify genome regions that discriminate taxa or groups of taxa and can be converted into PCR assays. The modular pipeline is comprised of four components: (1 selection and genome sequencing of phylogenetically related taxa, (2 identification of clusters of orthologous genes, (3 elimination of false positives by filtering, and (4 assay design. This pipeline was applied to some of the most important plant pathogens across three broad taxonomic groups: Phytophthoras (Stramenopiles, Oomycota, Dothideomycetes (Fungi, Ascomycota and Pucciniales (Fungi, Basidiomycota. Comparison of 73 fungal and Oomycete genomes led the discovery of 5,939 gene clusters that were unique to the targeted taxa and an additional 535 that were common at higher taxonomic levels. Approximately 28% of the 299 tested were converted into qPCR assays that met our set of specificity criteria. This work demonstrates that a genome-wide approach can efficiently identify multiple taxon-specific genome regions that can be converted into highly specific PCR assays. The possibility to easily obtain multiple alternative regions to design highly specific qPCR assays should be of great help in tackling challenging cases for which higher taxon-resolution is needed.

Muscodor albus Volatiles Control Toxigenic Fungi under Controlled Atmosphere (CA Storage Conditions

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Gordon Braun

2012-11-01

Full Text Available Muscodor albus, a biofumigant fungus, has the potential to control post-harvest pathogens in storage. It has been shown to produce over 20 volatile compounds with fungicidal, bactericidal and insecticidal properties. However, M. albus is a warm climate endophyte, and its biofumigant activity is significantly inhibited at temperatures below 5 °C. Conidia of seven mycotoxin producing fungi, Aspergillus carbonarius, A. flavus, A. niger, A. ochraceus, Penicillium verrucosum, Fusarium culmorum and F. graminearum, were killed or prevented from germinating by exposure to volatiles from 2 g M. albus-colonized rye grain per L of headspace in sealed glass jars for 24 h at 20 °C. Two major volatiles of M. albus, isobutyric acid (IBA and 2-methyl-1-butanol (2MB at 50 µL/L and 100 µL/L, respectively, gave differential control of the seven fungi when applied individually at 20 °C. When the fungi were exposed to both IBA and 2MB together, an average of 94% of the conidia were killed or suppressed. In a factorial experiment with controlled atmosphere storage (CA at 3 °C and 72 h exposure to four concentrations of IBA and 2MB combinations, 50 µL/L IBA plus 100 µL/L 2MB killed or suppressed germination of the conidia of all seven fungi. Controlled atmosphere had no significant effect on conidial viability or volatile efficacy. Major volatiles of M. albus may have significant potential to control plant pathogens in either ambient air or CA storage at temperatures below 5 °C. However, combinations of volatiles may be required to provide a broader spectrum of control than individual volatiles.

Genome wide analysis of the transition to pathogenic lifestyles in Magnaporthales fungi

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The rice blast fungus Pyricularia oryzae (syn. Magnaporthe oryzae, Magnaporthe grisea), a member of the order Magnaporthales in the class Sordariomycetes, is an important plant pathogen and a model species for studying pathogen infection and plant-fungal interaction. In this study, we generated geno...

Microbial Inhibition of Fusarium Pathogens and Biological Modification of Trichothecenes in Cereal Grains

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Urszula Wachowska

2017-12-01

Full Text Available Fungi of the genus Fusarium infect cereal crops during the growing season and cause head blight and other diseases. Their toxic secondary metabolites (mycotoxins contaminate grains. Several dozen toxic compounds produced by fungal pathogens have been identified to date. Type B trichothecenes—deoxynivalenol, its acetyl derivatives and nivalenol (produced mainly by F. graminearum and F. culmorum—are most commonly detected in cereal grains. “T-2 toxin” (produced by, among others, F. sporotrichioides belongs to type-A trichothecenes which are more toxic than other trichothecenes. Antagonistic bacteria and fungi can affect pathogens of the genus Fusarium via different modes of action: direct (mycoparasitism or hyperparasitism, mixed-path (antibiotic secretion, production of lytic enzymes and indirect (induction of host defense responses. Microbial modification of trichothecenes involves acetylation, deacetylation, oxidation, de-epoxidation, and epimerization, and it lowers the pathogenic potential of fungi of the genus Fusarium. Other modifing mechanisms described in the paper involve the physical adsorption of mycotoxins in bacterial cells and the conjugation of mycotoxins to glucose and other compounds in plant and fungal cells. The development of several patents supports the commercialization and wider application of microorganisms biodegrading mycotoxins in grains and, consequently, in feed additives.

Alergia ocular: un reto diagnóstico Ocular allergy: a diagnostic challenge

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Ricardo Cardona Villa

2007-12-01

Full Text Available El ojo es uno de los órganos más sensibles y está permanentemente expuesto a diversos agentes ambientales. Dado que la conjuntiva es un tejido inmunológicamente activo, no es sorprendente que sea un sitio común de respuestas alérgicas. Las alergias oculares son un grupo de enfermedades que afectan la superficie conjuntival y están asociadas usualmente a reacciones de hipersensibilidad tipo 1. Pueden ser divididas en varias categorías: conjuntivitis alérgica estacional, conjuntivitis alérgica perenne, queratoconjuntivitis vernal y queratoconjuntivitis atópica. La inflamación de la superficie ocular produce prurito, lagrimeo, edema conjuntival y fotofobia. Como en otras enfermedades alérgicas, se puede desarrollar una condición crónica, acompañada de remodelación de los tejidos oculares. Las estrategias para el tratamiento de la alergia ocular han aumentado exponencialmente y los clínicos disponen de un inventario cada vez mayor de agentes dirigidos a la protección del ojo contra la inflamación. En este trabajo presentamos una revisión sobre las principales formas de alergia ocular, haciendo énfasis en el cuadro clínico, el diagnóstico y las nuevas opciones terapéuticas disponibles en la actualidad. The eye, one of the most sensitive organs, is permanently exposed to different environmental agents. Since the conjunctiva is an immunologically active tissue, it is not surprising for it to be a common site for allergic responses. Ocular allergies constitute a group of diseases affecting the conjunctival surface; they are usually associated with type 1 hypersensitivity reactions. This disorder can be divided into several categories: seasonal allergic conjunctivitis, perennial allergic conjunctivitis, vernal keratoconjunctivitis and atopic keratoconjunctivitis. Ocular surface inflammation results in itching, tearing, conjunctival edema, and photophobia. As is the case with other allergic diseases, a chronic situation can also

Fungi and their role in corals and coral reef ecosystems

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C.; Ravindran, J.

fungal hyphae have on corals, their mechanism of penetration and the role their enzymes play in this process. 3.2. Fungi as pathogens in reef ecosystems Besides natural disasters and climate warming, diseases have contributed to coral decline... defence mechanisms against predation, biofouling, diseases, environmental perturbations and other stressors. These chemicals are either synthesized by the organisms themselves or their endobiontic microorganisms. If these valuable compounds...

An investigation of radiosensitivity of selected stored seed and seed borne fungi

International Nuclear Information System (INIS)

Maity, Jyoti Prakash; Chatterjee, S.; Mishra, D.; Chakraborty, A.; Saha, A.; Santra, S.C.; Chanda, S.

2004-01-01

Spoilage of nutritional value of the grains by the microbes, especially those producing mycotoxins, is a worldwide economic problem. The decontamination method, using gamma ray or fast electrons, is receiving growing attention. The present investigation was designed to determine an appropriate dose-range of gamma radiation for the stored grains to reduce levels of pathogenic fungi with minimal loss in viability, food value and/or germinating potential of the selected seeds. Further the study also aimed at assessing response of specific fungus to gamma irradiation in isolated condition and when attached to seeds to discern host-specific interaction if any, of the concerned fungi

Draft Genome Sequences of Human Pathogenic Fungus Geomyces pannorum Sensu Lato and Bat White Nose Syndrome Pathogen Geomyces (Pseudogymnoascus) destructans

OpenAIRE

Chibucos, Marcus C.; Crabtree, Jonathan; Nagaraj, Sushma; Chaturvedi, Sudha; Chaturvedi, Vishnu

2013-01-01

We report the draft genome sequences of Geomyces pannorum sensu lato and Geomyces (Pseudogymnoascus) destructans. G.?pannorum has a larger proteome than G.?destructans, containing more proteins with ascribed enzymatic functions. This dichotomy in the genomes of related psychrophilic fungi is a valuable target for defining their distinct saprobic and pathogenic attributes.

Pathogenicity characteristics of filamentous fungi strains isolated from processed oat Características de patogenicidade em amostras de fungos filamentosos isolados de aveia processada

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Eliane N. B. da Silva

1999-12-01

Full Text Available Nineteen strains of filamentous fungi isolated from processed oat were tested for pathogenicity factors, based on three parameters: growth at 37oC, production of phospholipase and urease. Aspergillus niveus, Oidiodendron gryseum and Sporothrix cyanescens were positive for the three parameters. The other species were positive only for one or two of them.Dezenove amostras de fungos filamentosos isoladas de aveia processada foram testadas quanto a fatores de patogenicidade, utilizando-se três parâmetros: crescimento a 37oC, atividades fosfolipásica e ureásica. Sporothrix cianescens, Aspergillus niveus e Oidiodendron gryseum apresentaram características de patogenicidade nos três testes realizados. As demais espécies apresentaram características de patogenicidade somente em um ou dois destes parâmetros.

The role of the arbuscular mycorrhiza-associated rhizobacteria in the biocontrol of soilborne phyto pathogens

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Lioussanne, L.

2010-07-01

The mutualistic symbiosis of most land plants with arbuscular mycorrhizal (AM) fungi has been shown to favor mineral and water nutrition and to increase resistance to abiotic and biotic stresses. This review reports the main mechanisms involved in the control of the disease symptoms and of the intraradical proliferation of soilborne phytopathogens by root colonization with AM fungi, with a special emphasis on the role of the rhizobacteria shown to be specifically associated with the AM extraradical network and the mycorrhizosphere (the soil zone with particular characteristics under the influence of the root/AM association). The mycorrhizosphere would constitute an environment conducive to microorganisms antagonistic to pathogen proliferation. Moreover, attempts to identify rhizobacteria from AM structures and/or the mycorrhizosphere often lead to the isolation of organisms showing strong properties of antagonism on various soilborne pathogens. The ability of AM fungi to control soilborne diseases would be strongly related to their capacity to specifically stimulate the establishment of rhizobacteria unfavorable to pathogen development within the mycorrhizosphere before root infection. Current knowledge concerning the mechanisms involved in AM/rhizobacteria interactions are also described in this review. (Author) 101 refs.

Entomopathogenic fungi as biological controllers: New insights into their virulence and pathogenicity

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Shahid Ali Ahmad; Rao Qayyum Abdul; Bakhsh Allah; Husnain Tayyab

2012-01-01

Entomopathogenic fungi vary considerably in their mode of action and virulence. Successful infection depends primarily on the adherence and penetration ability of a fungus to the host integuments. A variety of extracellular enzymes is produced during the degradation of insect integument. The attempts to control insects have changed over time from chemicals to natural control methods. This is why the development of natural methods of insect control or biopesticides, is preferred. By the ...

Mycoparasitism studies of Trichoderma species against three phytopathogenic fungi: evaluation of antagonism and hydrolytic enzyme production.

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Qualhato, Thiago Fernandes; Lopes, Fabyano Alvares Cardoso; Steindorff, Andrei Stecca; Brandão, Renata Silva; Jesuino, Rosália Santos Amorim; Ulhoa, Cirano José

2013-09-01

Trichoderma spp. are used for biocontrol of several plant pathogens. However, their efficient interaction with the host needs to be accompanied by production of secondary metabolites and cell wall-degrading enzymes. Three parameters were evaluated after interaction between four Trichoderma species and plant-pathogenic fungi: Fusarium solani, Rhizoctonia solani and Sclerotinia sclerotiorum. Trichoderma harzianum and T. asperellum were the most effective antagonists against the pathogens. Most of the Trichoderma species produced toxic volatile metabolites, having significant effects on growth and development of the plant pathogens. When these species were grown in liquid cultures with cell walls from these plant pathogens, they produced and secreted β-1,3-glucanase, NAGAse, chitinase, acid phosphatase, acid proteases and alginate lyase.

Deconstructing host-pathogen interactions in Drosophila

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Ethan Bier

2012-01-01

Full Text Available Many of the cellular mechanisms underlying host responses to pathogens have been well conserved during evolution. As a result, Drosophila can be used to deconstruct many of the key events in host-pathogen interactions by using a wealth of well-developed molecular and genetic tools. In this review, we aim to emphasize the great leverage provided by the suite of genomic and classical genetic approaches available in flies for decoding details of host-pathogen interactions; these findings can then be applied to studies in higher organisms. We first briefly summarize the general strategies by which Drosophila resists and responds to pathogens. We then focus on how recently developed genome-wide RNA interference (RNAi screens conducted in cells and flies, combined with classical genetic methods, have provided molecular insight into host-pathogen interactions, covering examples of bacteria, fungi and viruses. Finally, we discuss novel strategies for how flies can be used as a tool to examine how specific isolated virulence factors act on an intact host.

Assessing the potential effects of fungicides on nontarget gut fungi (trichomycetes) and their associated larval black fly hosts

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Wilson, Emma R.; Smalling, Kelly L.; Reilly, Timothy J.; Gray, Elmer; Bond, Laura; Steele, Lance; Kandel, Prasanna; Chamberlin, Alison; Gause, Justin; Reynolds, Nicole; Robertson, Ian; Novak, Stephen; Feris, Kevin; White, Merlin M.

2014-01-01

Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far-reaching consequences within aquatic ecosystems.

Nonhost resistance to rust pathogens - a continuation of continua.

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Bettgenhaeuser, Jan; Gilbert, Brian; Ayliffe, Michael; Moscou, Matthew J

2014-01-01

The rust fungi (order: Pucciniales) are a group of widely distributed fungal plant pathogens, which can infect representatives of all vascular plant groups. Rust diseases significantly impact several crop species and considerable research focuses on understanding the basis of host specificity and nonhost resistance. Like many pathogens, rust fungi vary considerably in the number of hosts they can infect, such as wheat leaf rust (Puccinia triticina), which can only infect species in the genera Triticum and Aegilops, whereas Asian soybean rust (Phakopsora pachyrhizi) is known to infect over 95 species from over 42 genera. A greater understanding of the genetic basis determining host range has the potential to identify sources of durable resistance for agronomically important crops. Delimiting the boundary between host and nonhost has been complicated by the quantitative nature of phenotypes in the transition between these two states. Plant-pathogen interactions in this intermediate state are characterized either by (1) the majority of accessions of a species being resistant to the rust or (2) the rust only being able to partially complete key components of its life cycle. This leads to a continuum of disease phenotypes in the interaction with different plant species, observed as a range from compatibility (host) to complete immunity within a species (nonhost). In this review we will highlight how the quantitative nature of disease resistance in these intermediate interactions is caused by a continuum of defense barriers, which a pathogen needs to overcome for successfully establishing itself in the host. To illustrate continua as this underlying principle, we will discuss the advances that have been made in studying nonhost resistance towards rust pathogens, particularly cereal rust pathogens.

The diversity and distribution of fungi on residential surfaces.

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Rachel I Adams

Full Text Available The predominant hypothesis regarding the composition of microbial assemblages in indoor environments is that fungal assemblages are structured by outdoor air with a moderate contribution by surface growth, whereas indoor bacterial assemblages represent a mixture of bacteria entered from outdoor air, shed by building inhabitants, and grown on surfaces. To test the fungal aspect of this hypothesis, we sampled fungi from three surface types likely to support growth and therefore possible contributors of fungi to indoor air: drains in kitchens and bathrooms, sills beneath condensation-prone windows, and skin of human inhabitants. Sampling was done in replicated units of a university-housing complex without reported mold problems, and sequences were analyzed using both QIIME and the new UPARSE approach to OTU-binning, to the same result. Surfaces demonstrated a mycological profile similar to that of outdoor air from the same locality, and assemblages clustered by surface type. "Weedy" genera typical of indoor air, such as Cladosporium and Cryptococcus, were abundant on sills, as were a diverse set of fungi of likely outdoor origin. Drains supported more depauperate assemblages than the other surfaces and contained thermotolerant genera such as Exophiala, Candida, and Fusarium. Most surprising was the composition detected on residents' foreheads. In addition to harboring Malassezia, a known human commensal, skin also possessed a surprising richness of non-resident fungi, including plant pathogens such as ergot (Claviceps purperea. Overall, fungal richness across indoor surfaces was high, but based on known autecologies, most of these fungi were unlikely to be growing on surfaces. We conclude that while some endogenous fungal growth on typical household surfaces does occur, particularly on drains and skin, all residential surfaces appear - to varying degrees - to be passive collectors of airborne fungi of putative outdoor origin, a view of the origins

Coloboma ocular: alterações oculares e sistêmicas associadas

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Tzelikis Patrick Frensel de Moraes

2004-01-01

Full Text Available OBJETIVO: Avaliar e comparar com a literatura o perfil dos pacientes portadores de colobomas oculares, bem como verificar a acuidade visual, alterações oculares associadas e alterações sistêmicas apresentadas pelos mesmos. MÉTODOS: Foram estudados retrospectivamente 18 pacientes com diagnóstico de coloboma ocular matriculados no serviço de Visão Subnormal do Hospital São Geraldo da Universidade Federal de Minas Gerais (HSG - HCUFMG. Foram avaliados: sexo, idade, raça, história familiar de anomalias oculares, história gestacional, tipo de coloboma, localização, bilateralidade, presença de microftalmia ou anoftalmia, alterações oculares concomitantes, e associação com doenças sistêmicas e acuidade visual. RESULTADO: Dez (55,6% pacientes eram do sexo feminino, 15 (83,3% eram leucodérmicos. A idade variou de 4 a 57 anos, com média de 9,5 anos. Apenas 3 (16,7% apresentavam história familiar para coloboma. Todos apresentavam história gestacional negativa para qualquer intercorrência. Houve acometimento bilateral em 100% dos casos, com microftalmia presente em 6 (33,3% casos. O coloboma foi típico em 14 (77,8% pacientes, sendo o coloboma mais comum o retinocoroidal ocorrendo em 16 (88,9% pacientes. 50% dos pacientes apresentavam o coloboma como achado isolado, e a outra metade associado a alguma doença sistêmica. Em 14 (77,8% pacientes foi encontrado algum tipo de alteração ocular além do coloboma. CONCLUSÃO: O exame oftalmológico completo é muito importante tanto no diagnóstico quanto no prognóstico de pacientes com coloboma, visto que este pode estar associado a uma baixa visual importante, além de poder estar relacionados a diferentes anomalias ou síndromes.

ISOLATION OF FILAMENTOUS FUNGI ASSOCIATED WITH TWO COMMON EDIBLE AQUATIC INSECTS, HYDROPHILUS PICEUS AND DYTISCUS MARGINALIS

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Ozlem Gur

2012-08-01

Full Text Available Insects are widely used for their potential source of protein, lipids, carbohydrates and certain vitamins in many parts of the world. As in terrestial ones, aquatic insects can also carry fungal structures. Therefore, in the present study, we evaluated microfungal flora of internal and external surface of Hydrophilus piceus and Dytiscus marginalis collected from their natural habitats in Erzurum (Turkey. We isolated total 19 different species of fungi belonging to Penicillium, Alternaria, Beauveria, Trichoderma, Fusarium, Aspergillus, Acremonium, Paecilomyces genera. The relationship between these fungi and edible insects was discussed further in the light of the existing literature. Among the isolated fungi, species that were recognized as pathogenic or toxigenic, and ones having biotechnological importance were found.

Draft Genome Sequences of Human Pathogenic Fungus Geomyces pannorum Sensu Lato and Bat White Nose Syndrome Pathogen Geomyces (Pseudogymnoascus) destructans.

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Chibucos, Marcus C; Crabtree, Jonathan; Nagaraj, Sushma; Chaturvedi, Sudha; Chaturvedi, Vishnu

2013-12-19

We report the draft genome sequences of Geomyces pannorum sensu lato and Geomyces (Pseudogymnoascus) destructans. G. pannorum has a larger proteome than G. destructans, containing more proteins with ascribed enzymatic functions. This dichotomy in the genomes of related psychrophilic fungi is a valuable target for defining their distinct saprobic and pathogenic attributes.

Biological activity of some bacterial isolates against soil borne pathogenic fungi

International Nuclear Information System (INIS)

Makbol, H.; Refae, R.I.; Eid, H.A.; Mohamed, O.M.

2011-01-01

The antagonistic activity of three bacterial isolates namely Micro bacterium terregens, Cellulosimicrobium cellulans and Bacillus amyloliquefaciens was evaluated through direct confrontation method and filtrates culture against the growth of Fusarium solani, Fusarium oxysporum, Rhizoctonia solani and Phytophthra cactorum. All bacterial isolates showed the inhibition of the mycelia growth of the isolated fungi as resulting to confrontation methods except R. solani with C. cellulans that showed no inhibitory effect and energized the low activity with B. amyloliquefaciens. Culture filtrate of different bacterial isolates after different incubation periods revealed that the highest antifungal activity between 3-10 days

Preservation methods for isolates of ascochyta blight fungi

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Joanna Marcinkowska

2014-08-01

Full Text Available Isolates of ascochyta blight fungi, two of Ascochyta pisi, four of Mycosphaerella pinodes and four of Phoma pinodella were stored: A - on slants under mineral oil, B - on CN's medium agar disks, and as conidial suspension: C - in glycerine, D · in water. Viability and pathogenicity of recovered cultures after each consecutive year were assesed from 1991 to 1999. The compared parameters were first of all strongly influenced by the preservation method, but fungus species and number of years had a minor importance. The best for longer storage was method "A" because after 9 years the isolates were viable, highly pathogenic, and cultures recovered from them were clean. Thc method "C'' is good for short keeping (2-3 years, as conidia in vials need only small space and gave clean cultures.

Antimicrobial evaluation of the crude extract of symbiotic fungi from marine sponge Reniera japonica

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Xuelian Bai

2018-05-01

Full Text Available Marine sponge-derived microbes are one of the rich sources of bioactive natural products with a broad spectrum of bioactivities. The present work focuses on the isolation and antimicrobial screening of the marine sponge-associated fungi from Reniera japonica MNP-2016. The results indicated that five fungi (L1-2, L2-1, L4, L8-1 and L14 were successfully isolated. Bioassay tests showed that only strain L14 had strong inhibitory effect on the pathogens, Staphyloccocus aureus, Escherichia coli and Candida albicans. 18S rDNA sequence analysis indicated that strain L14 was ascribed to Aspergillus genus. To the best of our knowledge, this work was the first report on the isolation and antimicrobial evaluation of fungi from R. japonica.

Widespread occurrence of honey bee pathogens in solitary bees.

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Ravoet, Jorgen; De Smet, Lina; Meeus, Ivan; Smagghe, Guy; Wenseleers, Tom; de Graaf, Dirk C

2014-10-01

Solitary bees and honey bees from a neighbouring apiary were screened for a broad set of putative pathogens including protists, fungi, spiroplasmas and viruses. Most sampled bees appeared to be infected with multiple parasites. Interestingly, viruses exclusively known from honey bees such as Apis mellifera Filamentous Virus and Varroa destructor Macula-like Virus were also discovered in solitary bees. A microsporidium found in Andrena vaga showed most resemblance to Nosema thomsoni. Our results suggest that bee hives represent a putative source of pathogens for other pollinators. Similarly, solitary bees may act as a reservoir of honey bee pathogens. Copyright © 2014 Elsevier Inc. All rights reserved.

In vitro suppression of fungi caused by combinations of apparently non-antagonistic soil bacteria.

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de Boer, Wietse; Wagenaar, Anne-Marieke; Klein Gunnewiek, Paulien J A; van Veen, Johannes A

2007-01-01

We hypothesized that apparently non-antagonistic soil bacteria may contribute to suppression of fungi during competitive interactions with other bacteria. Four soil bacteria (Brevundimonas sp., Luteibacter sp., Pedobacter sp. and Pseudomonas sp.) that exhibited little or no visible antifungal activity on different agar media were prescribed. Single and mixed strains of these species were tested for antagonism on a nutrient-poor agar medium against the plant pathogenic fungi Fusarium culmorum and Rhizoctonia solani and the saprotrophic fungus Trichoderma harzianum. Single bacterial strains caused little to moderate growth reduction of fungi (quantified as ergosterol), most probably due to nutrient withdrawal from the media. Growth reduction of fungi by the bacterial mixture was much stronger than that by the single strains. This appeared to be mostly due to competitive interactions between the Pseudomonas and Pedobacter strains. We argue that cohabitation of these strains triggered antibiotic production via interspecific interactions and that the growth reduction of fungi was a side-effect caused by the sensitivity of the fungi to bacterial secondary metabolites. Induction of gliding behavior in the Pedobacter strain by other strains was also observed. Our results indicate that apparently non-antagonistic soil bacteria may be important contributors to soil suppressiveness and fungistasis when in a community context.

First report of a cross-kingdom pathogenic bacterium, Achromobacter xylosoxidans isolated from stipe-rot Coprinus comatus.

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Ye, Luona; Guo, Mengpei; Ren, Pengfei; Wang, Gangzheng; Bian, Yinbing; Xiao, Yang; Zhou, Yan

2018-03-01

Coprinus comatus is an edible mushroom widely cultivated in China as a delicious food. Various diseases have occurred on C. comatus with the cultivated area increasing. In this study, the pathogenic bacterium JTG-B1, identified as Achromobacter xylosoxidans by 16S rDNA and nrdA gene sequencing, was isolated from edible mushroom Coprinus comatus with serious rot disease on its stipe. A. xylosoxidans has been confirmed as an important opportunistic human pathogenic bacterium and has been isolated from respiratory samples from cystic fibrosis. It is widely distributed in the environment. Here, we first report that fungi can also serve as a host for A. xylosoxidans. We confirmed that it can cross-kingdom infect between animals (mice) and fungi (C. comatus). The results of pathogenicity tests, physiological, biochemical and genotyping analysis of A. xylosoxidans from different hosts suggested that different strain of A. xylosoxidans may have pathogenicity differentiation. A. xylosoxidans not only is pathogenic to C. comatus but also may threaten human health. Copyright © 2017 Elsevier GmbH. All rights reserved.

Viable allergenic fungi in a documentary deposit of the National Archive of Cuba

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Alian Molina-Veloso

2017-02-01

Full Text Available Background: Intense and persistent exposure to indoor-air biological agents has been associated with the appearance of allergic diseases. Archives and libraries Indoor environments in tropical countries are an important reservoir of fungal propagules. Objective: To evaluate the degree of air pollution with allergenic fungi in a repository of frequently-manipulated documents. Methods: Air sampling was performed by two methods: active (biocollector and passive (sedimentation plate. Fungi were taxonomically identified, and spores were measured to determine their penetrability in the human respiratory tract, and its impact on episodes of allergy. Results: In terms of concentration and diversity, the local environment behaved as a fungal propagule reservoir, which showed that there is significant health risk for the staff that manipulates the documents. Some spores were shown to be able to reach the lower respiratory tract when inhaled, which increases their allergenic and pathogenic potential. Aspergillus, Cladosporium, Penicillium and Alternaria, which are referred to as highly allergenic fungi, were prevalent. Conclusion: Aerobiological studies are a valuable tool for the treatment of patients with allergy to fungi and other disorders they produce.

Metagenomic analysis of medicinal Cannabis samples; pathogenic bacteria, toxigenic fungi, and beneficial microbes grow in culture-based yeast and mold tests [version 1; referees: 2 approved, 1 approved with reservations

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Kevin McKernan

2016-10-01

Full Text Available Background: The presence of bacteria and fungi in medicinal or recreational Cannabis poses a potential threat to consumers if those microbes include pathogenic or toxigenic species. This study evaluated two widely used culture-based platforms for total yeast and mold (TYM testing marketed by 3M Corporation and Biomérieux, in comparison with a quantitative PCR (qPCR approach marketed by Medicinal Genomics Corporation. Methods: A set of 15 medicinal Cannabis samples were analyzed using 3M and Biomérieux culture-based platforms and by qPCR to quantify microbial DNA. All samples were then subjected to next-generation sequencing and metagenomics analysis to enumerate the bacteria and fungi present before and after growth on culture-based media. Results: Several pathogenic or toxigenic bacterial and fungal species were identified in proportions of >5% of classified reads on the samples, including Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, Ralstonia pickettii, Salmonella enterica, Stenotrophomonas maltophilia, Aspergillus ostianus, Aspergillus sydowii, Penicillium citrinum and Penicillium steckii. Samples subjected to culture showed substantial shifts in the number and diversity of species present, including the failure of Aspergillus species to grow well on either platform. Substantial growth of Clostridium botulinum and other bacteria were frequently observed on one or both of the culture-based TYM platforms. The presence of plant growth promoting (beneficial fungal species further influenced the differential growth of species in the microbiome of each sample. Conclusions: These findings have important implications for the Cannabis and food safety testing industries.

Influence of mycorrhizal fungi (glomus intraradices) on survival of Salmonella and E.coli 0157:H7 in soil and translocation into romaine lettuce roots and shoot

Science.gov (United States)

Modern agriculture practices disrupt the natural symbiotic relationship that arbuscular mycorrhizal (AM) fungi have with most vegetable plants, which may affect translocation of human pathogens into the plant and/or survival in the soil. AM-fungi are frequently utilized in organic farming to improv...

Antimicrobial potential of endophytic fungi derived from three seagrass species: Cymodocea serrulata, Halophila ovalis and Thalassia hemprichii.

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Preuttiporn Supaphon

Full Text Available Endophytic fungi from three commonly found seagrasses in southern Thailand were explored for their ability to produce antimicrobial metabolites. One hundred and sixty endophytic fungi derived from Cymodoceaserrulata (Family Cymodoceaceae, Halophilaovalis and Thalassiahemprichii (Family Hydrocharitaceae were screened for production of antimicrobial compounds by a colorimetric broth microdilution test against ten human pathogenic microorganisms including Staphylococcus aureus ATCC 25923, a clinical isolate of methicillin-resistant S. aureus, Escherichia coli ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Candida albicans ATCC 90028 and NCPF 3153, Cryptococcus neoformans ATCC 90112 and ATCC 90113 and clinical isolates of Microsporumgypseum and Penicilliummarneffei. Sixty-nine percent of the isolates exhibited antimicrobial activity against at least one test strain. Antifungal activity was more pronounced than antibacterial activity. Among the active fungi, seven isolates including Hypocreales sp. PSU-ES26 from C. serrulata, Trichoderma spp. PSU-ES8 and PSU-ES38 from H. ovalis, and Penicillium sp. PSU-ES43, Fusarium sp. PSU-ES73, Stephanonectria sp. PSU-ES172 and an unidentified endophyte PSU-ES190 from T. hemprichii exhibited strong antimicrobial activity against human pathogens with minimum inhibitory concentrations (MIC of less than 10 µg/ml. The inhibitory extracts at concentrations of 4 times their MIC destroyed the targeted cells as observed by scanning electron microscopy. These results showed the antimicrobial potential of extracts from endophytic fungi from seagrasses.

The Phytochemical and Antimicrobial Properties of Entomopathogenic Fungi in Nueva Vizcaya, Philippines

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Fitzgerald L. Fabelico

2015-12-01

Full Text Available Entomopathogenicfungi (EPF are potential biocontrol agents against agricultural pests and insects. These fungi are also known to be a source of secondary metabolites and could be a potential source of antibiotic drugs in the future. This study aims to determine the phytochemical and antimicrobial properties of EPF isolated from different host insects and their larvae in the province of Nueva Vizcaya.The method employed in this study includes the collection of EPF from dead insects and their larvae, isolation and mass production of the fungi, identification of the different fungi, extraction of secondary metabolites from the fungi, phytochemical screening, and antimicrobial assay. The results revealed that the antimicrobial properties of the different EPF could be explained by their phytochemical properties.When compared to the positive control, the significantly high antifungal activities of the Pandora neoaphidis(EPF 1 against the Candida albicans can be due to the presence of sterols. Conversely, the significantly high antibacterial activities of Beauveria alba (EPF 5 against Bacillus subtiliscould be due to the presence ofsteroids, triterpenoids, glycosides, and fatty acids.These findings indicate that entomopathogenic fungi could be a potential source of antibiotic drugs against pathogenic microorganism in the near future. To realize this, future research is highly recommended for the isolation, elucidation, and evaluation of the safety of the bioactive compounds of entomopathogenic fungi responsible for the antimicrobial activities, prior to their use in humans.

The virulence of human pathogenic fungi: notes from the South of France.

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Reedy, Jennifer L; Bastidas, Robert J; Heitman, Joseph

2007-08-16

The Second FEBS Advanced Lecture Course on Human Fungal Pathogens: Molecular Mechanisms of Host-Pathogen Interactions and Virulence, organized by Christophe d'Enfert (Institut Pasteur, France), Anita Sil (UCSF, USA), and Steffen Rupp (Fraunhofer, IGB, Germany), occurred May 2007 in La Colle sur Loup, France. Here we review the advances presented and the current state of knowledge in key areas of fungal pathogenesis.

Pathogenicity of two seed-borne fungi commonly involved in maize ...

African Journals Online (AJOL)

Nazar Hussain

2013-03-20

Mar 20, 2013 ... pathogenicity on seeds and 6.55% on seedlings, whilst Aspergillus niger had 62.87% .... Nigrospora oryzae .... PDA culture in test tubes slants; (b) Fusarium moniliforme PDA culture in test tubes slants; (c) Mycoflora culture of.

The Frequency Of Fungi In Doubtful Appendicitis

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J Hashemi

2006-06-01

Full Text Available Background and Aim: While nowadays,great attainments have been achieved in curing and preventing the pathogenic fungal infections, and some how there has been reduction in the number of occurrences, the occurrences of opportunistic infections have been increased. Since the study of fungal infections in various organs (e.g.digestive system is crucial ,and because of few study were done in this field in the world, it is decided to examine the apendectomide tissue for fungal contamination in Iran. Materials and Methods: The work has been done for six months. After oparation sergery the appendix tissue in two media (formalin & normal salin were carried out in the medical mycology laboratory at Tehran University of medical sciences. The specimens were examined directly and cultured in sabourauds dextrose agar with chloramphenicol (sc. In this experiment 200 appendicular tissues were examined. Results: Out of them some fungi were isolated in 10 cases included 4 Candida albican (40%, 2 Candida tropicalis (20%,1 Cryptococcus sp. (10%,1 Candida sp.and 2 Geotrichum sp. Cryptococcus sp. was identified with mycological methods. This isolation related to a young man that has a history for long contact to pigeon.some of the fungi specially yeast can be a part of mycoflora in digestive system but the finding of Cryptococcus is uncommon. Conclusion: In this study the fungi were isolated from 5% of appendisits and with pay attention to this finding that the most patients hadn.t background factors causing the proliferation of the fungal agents in the intestine, so with further studies it is probable to consider the fungi as the agents causing appendicitis in this patients.

Gold nanoparticles synthesized by Brassica oleracea (Broccoli) acting as antimicrobial agents against human pathogenic bacteria and fungi

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Piruthiviraj, Prakash; Margret, Anita; Krishnamurthy, Poornima Priyadharsani

2016-04-01

Production of antimicrobial agents through the synthesis of gold nanoparticles using green technology has been extensively made consistent by various researchers; yet, this study uses the flower bud's aqueous extracts of Brassica oleracea (Broccoli) as a reducing agent for chloroauric acid (1 mM). After 30 min of incubation, synthesis of gold nanoparticles (AuNps) was observed by a change in extract color from pale yellow to purple color. Synthesis of AuNps was confirmed in UV-visible spectroscopy at the range of approximately 560 nm. The SEM analysis showed the average nanoparticles size of 12-22 nm. The antimicrobial activity of AuNps was analyzed by subjecting it to human pathogenic bacteria (Gram-positive Staphylococcus aureus and Gram-negative Klebsiella pneumonia) and fungi (Aspergillus flavus, Aspergillus niger and Candida albicans) using disc diffusion method. The broccoli-synthesized AuNps showed the efficient antibacterial and antifungal activity of above-mentioned microbes. It was confirmed that AuNps have the best antimicrobial agent compared to the standard antibiotics (Gentamicin and Fluconazole). When the concentrations of AuNps were increased (10, 25, and 50 µg/ml), the sensitivity zone also increased for all the tested microbes. The synthesized AuNps are capable of rendering high antimicrobial efficacy and, hence, have a great potential in the preparation of drugs used against major bacterial and fungal diseases in humans.

Isolation and antifungal screening of endophytic fungi from Erigeron canadensis

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Xuelian Bai

2017-07-01

Full Text Available Sixteen fungal strains isolated from the Erigeron canadensis, one of traditional Chinese medicines used to treat the pathogenic infection and dysentery, were evaluated for their antifungal activities against one human pathogen Candida albicans, and two phytopathogens, Colletotrichum fructicola and Rhizoctonia cerealis. The bioassay results indicated that the ethyl acetate extract of the fermentation broth of these fungal endophytes had stronger antimicrobial activities. Among these endophytic strains, the ethyl acetate extracts of strains NPR003 and NPR005 showed the strongest inhibitory effects and has potential application in the discovery of new antifungal agents. This was the first report on the isolation of endophytic fungi from E. canadensis and evaluation of their antifungal activities.

Antifungal potential of Bacillus vallismortis R2 against different phytopathogenic fungi

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Kaur, P.K.; Kaur, J.; Saini, H.S.

2015-07-01

The cash crops grown in an agro-climatic region are prone to infection by various fungal pathogens. The use of chemical fungicides over the years has resulted in emergence of resistant fungal strains, thereby necessitating the development of effective and environmental friendly alternatives. The natural antagonistic interactions among different microbial populations have been exploited as an eco-friendly approach for controlling fungal pathogens resistant to synthetic chemicals. Morphologically distinct bacterial cultures (150), isolated from rhizospheric soils of wheat, rice, onion and tomato plants were screened for their antifungal potential against seven phytopathogenic fungi prevalent in the State of Punjab (India). The bacterial isolate R2, identified as Bacillus vallismortis, supported more than 50% inhibition of different phytopathogenic fungi (Alternaria alternata, Rhizoctonia oryzae, Fusarium oxysporum, Fusarium moniliforme, Colletotrichum sp, Helminthosporium sp and Magnaporthe grisea) in dual culture plate assay. The thin layer chromatography based bio-autography of acid-precipitated biomolecules (APB) indicated the presence of more than one type of antifungal molecule, as evidenced from zones of inhibition against the respective fungal pathogen. The initial analytical studies indicated the presence of surfactin, iturin A and fengycin-like compounds in APB. The antifungal activity of whole cells and APB of isolate R2 was evaluated by light and scanning electron microscopy. The wheat grains treated with APB and exposed to spores of A. alternata showed resistance to the development of black point disease, thereby indicating the potential application of R2 and its biomolecules at field scale level. (Author)

Function of VtPGIP in pathogenic fungus resistance of Vitis thunbergii

African Journals Online (AJOL)

edoja

2014-02-19

Feb 19, 2014 ... with pathogenic fungi and water were harvested, immediately frozen in liquid nitrogen, and stored at ... structure of the VtPGIP protein and molecular modeling were analyzed using Swiss-Pdb Viewer 3.7. Cloning of the VtPGIP ...

Disease-Causing Fungi in Homes and Yards in the Midwestern United States

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Dennis J. Baumgardner

2016-04-01

Full Text Available A number of fungal pathogens that may result in a variety of human diseases are found in residential homes and yards. The growth of these microscopic fungi is often favored by particular characteristics of the dwelling and nearby outdoor environment. Evolved virulence factors or increased ability of specific fungi to grow in diverse, and sometimes harsh, microenvironments presented by the domestic environment may promote growth and pathogenesis. Infection may occur by inhalation or direct inoculation and include endemic fungi in addition to opportunistic or emerging species. Systemic or locally aggressive fungal infections are particularly likely and may be life-threatening in those with compromised immune systems. Allergic disease may include sinusitis, pneumonitis and immediate hypersensitivity. Controversial topics include mycotoxins, volatile organic compounds and sick building syndrome. This narrative review describes the usual presentations, domestic environmental sources, prevention techniques and risk of acquiring these diseases in the Midwestern United States.

Gene therapy for ocular diseases.

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Liu, Melissa M; Tuo, Jingsheng; Chan, Chi-Chao

2011-05-01

The eye is an easily accessible, highly compartmentalised and immune-privileged organ that offers unique advantages as a gene therapy target. Significant advancements have been made in understanding the genetic pathogenesis of ocular diseases, and gene replacement and gene silencing have been implicated as potentially efficacious therapies. Recent improvements have been made in the safety and specificity of vector-based ocular gene transfer methods. Proof-of-concept for vector-based gene therapies has also been established in several experimental models of human ocular diseases. After nearly two decades of ocular gene therapy research, preliminary successes are now being reported in phase 1 clinical trials for the treatment of Leber congenital amaurosis. This review describes current developments and future prospects for ocular gene therapy. Novel methods are being developed to enhance the performance and regulation of recombinant adeno-associated virus- and lentivirus-mediated ocular gene transfer. Gene therapy prospects have advanced for a variety of retinal disorders, including retinitis pigmentosa, retinoschisis, Stargardt disease and age-related macular degeneration. Advances have also been made using experimental models for non-retinal diseases, such as uveitis and glaucoma. These methodological advancements are critical for the implementation of additional gene-based therapies for human ocular diseases in the near future.

Trachoma: protective and pathogenic ocular immune responses to Chlamydia trachomatis.

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Victor H Hu

Full Text Available Trachoma, caused by Chlamydia trachomatis (Ct, is the leading infectious blinding disease worldwide. Chronic conjunctival inflammation develops in childhood and leads to eyelid scarring and blindness in adulthood. The immune response to Ct provides only partial protection against re-infection, which can be frequent. Moreover, the immune response is central to the development of scarring pathology, leading to loss of vision. Here we review the current literature on both protective and pathological immune responses in trachoma. The resolution of Ct infection in animal models is IFNγ-dependent, involving Th1 cells, but whether this is the case in human ocular infection still needs to be confirmed. An increasing number of studies indicate that innate immune responses arising from the epithelium and other innate immune cells, along with changes in matrix metalloproteinase activity, are important in the development of tissue damage and scarring. Current trachoma control measures, which are centred on repeated mass antibiotic treatment of populations, are logistically challenging and have the potential to drive antimicrobial resistance. A trachoma vaccine would offer significant advantages. However, limited understanding of the mechanisms of both protective immunity and immunopathology to Ct remain barriers to vaccine development.

Plant pathogens as biocontrol agents of Cirsium arvense – an overestimated approach?

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Esther Müller

2011-11-01

Full Text Available Cirsium arvense is one of the worst weeds in agriculture. As herbicides are not very effective and not accepted by organic farming and special habitats, possible biocontrol agents have been investigated since many decades. In particular plant pathogens of C. arvense have received considerable interest and have been promoted as “mycoherbicides” or “bioherbicides”. A total of 10 fungi and one bacterium have been proposed and tested as biocontrol agents against C. arvense. A variety of experiments analysed the noxious influence of spores or other parts of living fungi or bacteria on plants while others used fungal or bacterial products, usually toxins. Also combinations of spores with herbicides and combinations of several pathogens were tested. All approaches turned out to be inappropriate with regard to target plant specificity, effectiveness and application possibilities. As yet, none of the tested species or substances has achieved marketability, despite two patents on the use of Septoria cirsii and Phomopsis cirsii. We conclude that the potential of pathogens for biocontrol of C. arvense has largely been overestimated.

Molecular Diagnostics for Soilborne Fungal Pathogens

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E.J. Paplomatas

2004-08-01

Full Text Available Several classical approaches have been developed to detect and identify soil fungal inhabitants through the years. Selective media have been devised to exclude the large number of soil organisms and allow growth of target fungi. However the advent of molecular biology has offered a number of revolutionary insights into the detection and enumeration of soilborne fungal pathogens and also has started to provide information on the identification of unknown species from DNA sequences. This review paper focuses on the application of various molecular techniques in the detection, identification, characterization and quantification of soilborne fungal plant pathogens. This is based on information from the literature and is combined with personal research findings of the author.

Diversity and antimicrobial activity of culturable endophytic fungi isolated from moso bamboo seeds.

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Xiao-Ye Shen

Full Text Available Bamboos, regarded as therapeutic agents in ethnomedicine, have been used to inhibit inflammation and enhance natural immunity for a long time in Asia, and there are many bamboo associated fungi with medical and edible value. In the present study, a total of 350 fungal strains were isolated from the uncommon moso bamboo (Phyllostachys edulis seeds for the first time. The molecular diversity of these endophytic fungi was investigated and bioactive compound producers were screened for the first time. All the fungal endophytes were categorized into 69 morphotypes according to culturable characteristics and their internal transcriber spacer (ITS regions were analyzed by BLAST search with the NCBI database. The fungal isolates showed high diversity and were divided in Ascomycota (98.0% and Basidiomycota (2.0%, including at least 19 genera in nine orders. Four particular genera were considered to be newly recorded bambusicolous fungi, including Leptosphaerulina, Simplicillium, Sebacina and an unknown genus in Basidiomycetes. Furthermore, inhibitory effects against clinical pathogens and phytopathogens were screened preliminarily and strains B09 (Cladosporium sp., B34 (Curvularia sp., B35 (undefined genus 1, B38 (Penicillium sp. and zzz816 (Shiraia sp. displayed broad-spectrum activity against clinical bacteria and yeasts by the agar diffusion method. The crude extracts of isolates B09, B34, B35, B38 and zzz816 under submerged fermentation, also demonstrated various levels of bioactivities against bambusicolous pathogenic fungi. This study is the first report on the antimicrobial activity of endophytic fungi associated with moso bamboo seeds, and the results show that they could be exploited as a potential source of bioactive compounds and plant defense activators. In addition, it is the first time that strains of Shiraia sp. have been isolated and cultured from moso bamboo seeds, and one of them (zzz816 could produce hypocrellin A at high yield, which

Analysis of the community compositions of rhizosphere fungi in soybeans continuous cropping fields.

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Bai, Li; Cui, Jiaqi; Jie, Weiguang; Cai, Baiyan

2015-11-01

We used rhizosphere soil sampled from one field during zero year and two years of continuous cropping of high-protein soybean to analyze the taxonomic community compositions of fungi during periods of high-incidence of root rot. Our objectives were to identify the dominant pathogens in order to provide a theoretical basis for the study of pathogenesis as well as control tactics for soybean root rot induced by continuous cropping. A total of 17,801 modified internal transcribed spacer (ITS) sequences were obtained from three different soybean rhizosphere soil samples after zero year and 1 or 2 years of continuous cropping using 454 high-throughput sequencing. The dominant eumycote fungal were identified to be Ascomycota and Basidiomycota in the three soil samples. Continuous cropping of soybean affected the diversity of fungi in rhizosphere soils and increased the abundance of Thelebolus and Mortierellales significantly. Thanatephorus, Fusarium, and Alternaria were identified to be the dominant pathogenic fungal genera in rhizosphere soil from continuously cropped soybean fields. Copyright © 2015 Elsevier GmbH. All rights reserved.

Isolation of fungi from nature in the region of Botucatu, state of São Paulo, Brazil, an endemic area of paracoccidioidomycosis

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MR Montenegro

1996-12-01

Full Text Available In an attempt to isolate Paracoccidioides brasiliensis from nature 887 samples of soil from Botucatu, SP, Brazil, were collected cultured in brain heart infusion agar supplemented with dextrose, in potato dextrose agar and in yeast extract starch dextrose agar, all with antibiotics, at 25º and 37ºC. Five thermo-dependent dimorphic fungi morphologically resembling P. brasiliensis were isolated; two from armadillo holes; further studies of the biology, antigenicity and genetic features of the five dimorphic fungi are necessary to clarify their taxonomy and their possible relation to P. brasiliensis. In addition, 98 dematiaceous fungi and 581 different species of Aspergillus spp. were also isolated. Our findings emphasize that armadillos and their environment are associated with thermo-dimorphic fungi and confirm the ubiquity of pathogenic dematiaceous fungi and Aspergillus spp.

A field study using the fungicide benomyl to investigate the effect of mycorrhizal fungi on plant fitness.

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Carey, Peter D; Fitter, Alastair H; Watkinson, Andrew R

1992-07-01

The effect of vesicular-arbuscular mycorrhiza (VAM) on the fecundity ofVulpia ciliata ssp.ambigua was investigated at two field sites in eastern England by applying the fungicide benomyl to reduce VAM infection. The application of benomyl at the two sites produced very different results. At one site the application of the fungicide reduced the fecundity of plants whereas at the other fecundity was increased. At the first site the reduction in fecundity was linked to a significant reduction in VAM infection on the sprayed plants. The mechanism of the benefit associated with the VAM infection is however unclear: there was no treatment effect on morphology or on phosphorus inflow. At the second site, where fecundity was increased, there was only a negligible amount of VAM infection amongst the unsprayed plants and it is suggested that the increase in fecundity with the application of benomyl may have resulted from a reduction in infection by other, presumably pathogenic, fungi. The value of VAM fungi to the host plant may therefore not be restricted to physiological benefits. They may also provide protection to the plant by competing for space with other species of pathogenic fungi.

Nonhost resistance to rust pathogens – a continuation of continua

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Jan eBettgenhaeuser

2014-12-01

Full Text Available The rust fungi (order: Pucciniales are a group of widely distributed fungal plant pathogens, which can infect representatives of all vascular plant groups. Rust diseases significantly impact several crop species and considerable research focuses on understanding the basis of host specificity and nonhost resistance. Like many pathogens, rust fungi vary considerably in the number of hosts they can infect, such as wheat leaf rust (Puccinia triticina, which can only infect species in the genera Triticum and Aegilops, whereas Asian soybean rust (Phakopsora pachyrhizi is known to infect over 95 species from over 42 genera. A greater understanding of the genetic basis determining host range has the potential to identify sources of durable resistance for agronomically important crops. Delimiting the boundary between host and nonhost has been complicated by the quantitative nature of phenotypes in the transition between these two states. Plant-pathogen interactions in this intermediate state are characterized either by (1 the majority of accessions of a species being resistant to the rust or (2 the rust only being able to partially complete key components of its life cycle. This leads to a continuum of disease phenotypes in the interaction with different plant species, observed as a range from compatibility (host to complete immunity within a species (nonhost. In this review we will highlight how the quantitative nature of disease resistance in these intermediate interactions is caused by a continuum of defense barriers, which a pathogen needs to overcome for successfully establishing itself in the host. To illustrate continua as this underlying principle, we will discuss the advances that have been made in studying nonhost resistance towards rust pathogens, particularly cereal rust pathogens.

Nonhost resistance to rust pathogens – a continuation of continua

Science.gov (United States)

Bettgenhaeuser, Jan; Gilbert, Brian; Ayliffe, Michael; Moscou, Matthew J.

2014-01-01

The rust fungi (order: Pucciniales) are a group of widely distributed fungal plant pathogens, which can infect representatives of all vascular plant groups. Rust diseases significantly impact several crop species and considerable research focuses on understanding the basis of host specificity and nonhost resistance. Like many pathogens, rust fungi vary considerably in the number of hosts they can infect, such as wheat leaf rust (Puccinia triticina), which can only infect species in the genera Triticum and Aegilops, whereas Asian soybean rust (Phakopsora pachyrhizi) is known to infect over 95 species from over 42 genera. A greater understanding of the genetic basis determining host range has the potential to identify sources of durable resistance for agronomically important crops. Delimiting the boundary between host and nonhost has been complicated by the quantitative nature of phenotypes in the transition between these two states. Plant–pathogen interactions in this intermediate state are characterized either by (1) the majority of accessions of a species being resistant to the rust or (2) the rust only being able to partially complete key components of its life cycle. This leads to a continuum of disease phenotypes in the interaction with different plant species, observed as a range from compatibility (host) to complete immunity within a species (nonhost). In this review we will highlight how the quantitative nature of disease resistance in these intermediate interactions is caused by a continuum of defense barriers, which a pathogen needs to overcome for successfully establishing itself in the host. To illustrate continua as this underlying principle, we will discuss the advances that have been made in studying nonhost resistance towards rust pathogens, particularly cereal rust pathogens. PMID:25566270

Entomopathogenic fungi as biological control agents of diamondback moth (Lepidoptera: Plutellidae)and compatibility with chemical insecticides

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The objectives were to evaluate the efficiency of entomopathogenic fungi against Plutella xylostella (L.) and the compatibility of the most virulent isolates with some of the insecticides registered for use on cabbage crops. Pathogenicity tests used isolates of Beauveria bassiana, Metarhizium rileyi...

Comparative genomics and transcriptomics depict ericoid mycorrhizal fungi as versatile saprotrophs and plant mutualists.

Science.gov (United States)

Martino, Elena; Morin, Emmanuelle; Grelet, Gwen-Aëlle; Kuo, Alan; Kohler, Annegret; Daghino, Stefania; Barry, Kerrie W; Cichocki, Nicolas; Clum, Alicia; Dockter, Rhyan B; Hainaut, Matthieu; Kuo, Rita C; LaButti, Kurt; Lindahl, Björn D; Lindquist, Erika A; Lipzen, Anna; Khouja, Hassine-Radhouane; Magnuson, Jon; Murat, Claude; Ohm, Robin A; Singer, Steven W; Spatafora, Joseph W; Wang, Mei; Veneault-Fourrey, Claire; Henrissat, Bernard; Grigoriev, Igor V; Martin, Francis M; Perotto, Silvia

2018-02-01

Some soil fungi in the Leotiomycetes form ericoid mycorrhizal (ERM) symbioses with Ericaceae. In the harsh habitats in which they occur, ERM plant survival relies on nutrient mobilization from soil organic matter (SOM) by their fungal partners. The characterization of the fungal genetic machinery underpinning both the symbiotic lifestyle and SOM degradation is needed to understand ERM symbiosis functioning and evolution, and its impact on soil carbon (C) turnover. We sequenced the genomes of the ERM fungi Meliniomyces bicolor, M. variabilis, Oidiodendron maius and Rhizoscyphus ericae, and compared their gene repertoires with those of fungi with different lifestyles (ecto- and orchid mycorrhiza, endophytes, saprotrophs, pathogens). We also identified fungal transcripts induced in symbiosis. The ERM fungal gene contents for polysaccharide-degrading enzymes, lipases, proteases and enzymes involved in secondary metabolism are closer to those of saprotrophs and pathogens than to those of ectomycorrhizal symbionts. The fungal genes most highly upregulated in symbiosis are those coding for fungal and plant cell wall-degrading enzymes (CWDEs), lipases, proteases, transporters and mycorrhiza-induced small secreted proteins (MiSSPs). The ERM fungal gene repertoire reveals a capacity for a dual saprotrophic and biotrophic lifestyle. This may reflect an incomplete transition from saprotrophy to the mycorrhizal habit, or a versatile life strategy similar to fungal endophytes. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Ocular emergencies presenting to Menelik II Hospital.

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Negussie, Dereje; Bejiga, Abebe

2011-01-01

Ocular conditions such as trauma, painful red eye of any cause, painless sudden visual loss and others are commonly seen as ocular emergencies, and can lead to ocular morbidity and visual loss. To determine types and causes of ocular emergencies seen at Menelik II hospital. A cross-sectional study was conducted from April to October, 2007. Consecutive patients who presented with ocular emergencies at any time of the day were prospectively evaluated and registered on a formatted questionnaire. Evaluation of the patients included history of presenting illness, visual acuity testing intraocular pressure measurement on non-perforated and non-infected eyes, and complete eye examination in order to arrive at the diagnosis. A total of 26,400 patients attended Menelik II hospital during the study period. Of these, 758 (3%) were persons with an ocular emergency. The majority of patients (n=551; 72.7%) were male, with a male to female ratio of 2.7:1. The age group of 16 to 30 years was the most affected (47.9%), followed by those aged 15 years or younger (27.3%). Ocular trauma and ocular infections accounted for 75.6% and 13.1% of cases, respectively. Of the total ocular emergencies, open globe injuries constituted 171 (22.6%), corneal foreign bodies and abrasion 125 (16.5%), and open adnexal injuries 119 (15.7%). Metal and wood were the commonest work-related causes of ocular injuries in adults, with both together accounting for 60% of all ocular injuries. Children, on the other hand, sustained ocular injury while playing with others in 128 (22.3%) of cases. This study was able to provide a more complete picture to improve understanding of the nature and circumstances of ocular emergencies in Ethiopia. Ocular emergencies were dominated by ocular trauma, particularly affecting males and working-age adults. Public education and use of protective safety measures are recommended to alleviate the problem.

Raft-like membrane domains in pathogenic microorganisms.

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Farnoud, Amir M; Toledo, Alvaro M; Konopka, James B; Del Poeta, Maurizio; London, Erwin

2015-01-01

The lipid bilayer of the plasma membrane is thought to be compartmentalized by the presence of lipid-protein microdomains. In eukaryotic cells, microdomains composed of sterols and sphingolipids, commonly known as lipid rafts, are believed to exist, and reports on the presence of sterol- or protein-mediated microdomains in bacterial cell membranes are also appearing. Despite increasing attention, little is known about microdomains in the plasma membrane of pathogenic microorganisms. This review attempts to provide an overview of the current state of knowledge of lipid rafts in pathogenic fungi and bacteria. The current literature on characterization of microdomains in pathogens is reviewed, and their potential role in growth, pathogenesis, and drug resistance is discussed. Better insight into the structure and function of membrane microdomains in pathogenic microorganisms might lead to a better understanding of their pathogenesis and development of raft-mediated approaches for therapy. Copyright © 2015 Elsevier Inc. All rights reserved.

Identification of Contaminated Cells with Viruses, Bacteria, or Fungi by Fourier Transform Infrared Microspectroscopy

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V. Erukhimovitch

2013-01-01

Full Text Available Fourier transform infrared microspectroscopy (FTIR-M can detect small molecular changes in cells and therefore was previously applied for the identification of different biological samples. In the present study, FTIR spectroscopy was used for the identification and discrimination of Vero cells infected with herpes viruses or contaminated with bacteria or fungi in cell culture. Vero cells in culture were infected herpes simplex virus type 1 (HSV-1 or contaminated with E. coli bacteria or Candida albicans fungi and analyzed by FTIR microscopy at 24 h postinfection/contamination. Specific different spectral changes were observed according to the infecting or contaminating agent. For instance, both pure fungi and cell culture contaminated with this fungi showed specific peaks at 1030 cm−1 and at 1373 cm−1 regions, while pure E. coli and cell culture contaminated with this bacteria showed a specific and unique peak at 1657 cm−1. These results support the potential of developing FTIR microspectroscopy as a simple, reagent free method for identification and discrimination between different tissue infection or contamination with various pathogens.

Candida and Fusarium species known as opportunistic human pathogens from customer-accessible parts of residential washing machines.

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Babič, Monika Novak; Zalar, Polona; Ženko, Bernard; Schroers, Hans-Josef; Džeroski, Sašo; Gunde-Cimerman, Nina

2015-03-01

Energy constraints have altered consumer practice regarding the use of household washing machines. Washing machines were developed that use lower washing temperatures, smaller amounts of water and biodegradable detergents. These conditions may favour the enrichment of opportunistic human pathogenic fungi. We focused on the isolation of fungi from two user-accessible parts of washing machines that often contain microbial biofilms: drawers for detergents and rubber door seals. Out of 70 residential washing machines sampled in Slovenia, 79% were positive for fungi. In total, 72 strains belonging to 12 genera and 26 species were isolated. Among these, members of the Fusarium oxysporum and Fusarium solani species complexes, Candida parapsilosis and Exophiala phaeomuriformis represented 44% of fungi detected. These species are known as opportunistic human pathogens and can cause skin, nail or eye infections also in healthy humans. A machine learning analysis revealed that presence of detergents and softeners followed by washing temperature, represent most critical factors for fungal colonization. Three washing machines with persisting malodour that resulted in bad smelling laundry were analysed for the presence of fungi and bacteria. In these cases, fungi were isolated in low numbers (7.5 %), while bacteria Micrococcus luteus, Pseudomonas aeruginosa, and Sphingomonas species prevailed. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Fungi and fungi-like Oomycetes isolated from affected leaves of rhododendron

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Maria Kowalik

2013-12-01

Full Text Available The aim of the work is to identify fungi and fungi-like Oomycetes occurring on affected leaves of rhododendron Rhododendron L. Mycological analyses were carried out on 200 leaves collected from green areas of Kraków from May till September 2005. Isolated fungi-like Oomycetes belonged to 67 taxa. The most frequently found fungi included: Alternaria alternata, Aspergillus niger, Botrytis cinerea, Coelophoma empetri, Nigrospora sphaerica, Pestalotia sydowiana, Phialophora cyclaminis, Phomopsis archeri, Septoria azalea and Sordaria fimicola. Among fungi-like organisms Phytophthora cinnamomi and P. citricola were isolated.

Ocular pulsation correlates with ocular tension: the choroid as piston for an aqueous pump?

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Phillips, C I; Tsukahara, S; Hosaka, O; Adams, W

1992-01-01

In 26 random out-patients, including 13 treated glaucoma patients and ocular hypertensives, the higher the ocular tension, the greater the pulse amplitude, by Alcon pneumotonometry, at a statistically significant level. In a single untreated hypertensive, when 2-hourly pneumotonometry was done for 24 h, the correlation was similar and significant. The higher the diastolic blood pressure, the higher the ocular pulsation, also significantly. Pulsation is suggested to be a pump, the choroid being the piston, contributing (1) to an increase in the outflow of aqueous humour and (2) to a homeostatic mechanism contributing to normalization of the intra-ocular pressure, wherein pulsation increases or decreases, as the intraocular pressure increases or decreases, respectively.

Aspergilli: Models for systems biology in filamentous fungi

DEFF Research Database (Denmark)

Brandl, Julian; Andersen, Mikael Rørdam

2017-01-01

and proteomics where outstanding contributions are highlighted. From past developments it becomes apparent that CRISPR technology will speed up genetic research in the Aspergillus field. This speed up will allow for an increase in systems biology targeted research by accelerating data generation. The increase......Aspergillus is a diverse genus of filamentous fungi including common house hold mold as well as human pathogens. More than 350 species are currently part of this genus and all their genomes are soon to be sequenced. The availability of this vast amount of data will allow for more in...

Multiple genotypes within aecial clusters in Puccinia graminis and Puccinia coronata: improved understanding of the biology of cereal rust fungi.

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Berlin, Anna; Samils, Berit; Andersson, Björn

2017-01-01

Cereal rust fungi ( Puccinia spp.) are among the most economically important plant pathogens. These fungi have a complex life cycle, including five spore stages and two hosts. They infect one grass host on which they reproduce clonally and cause the cereal rust diseases, while the alternate host is required for sexual reproduction. Although previous studies clearly demonstrate the importance of the alternate host in creating genetic diversity in cereal rust fungi, little is known about the amount of novel genotypes created in each successful completion of a sexual reproduction event. In this study, single sequence repeat markers were used to study the genotypic diversity within aecial clusters by genotyping individual aecial cups. Two common cereal rusts, Puccinia graminis causing stem rust and Puccinia coronata the causal agent of crown rust were investigated. We showed that under natural conditions, a single aecial cluster usually include several genotypes, either because a single pycnial cluster is fertilized by several different pycniospores, or because aecia within the cluster are derived from more than one fertilized adjoining pycnial cluster, or a combination of both. Our results imply that although sexual events in cereal rust fungi in most regions of the world are relatively rare, the events that occur may still significantly contribute to the genetic variation within the pathogen populations.

Hyphema as a Complication of Blunt Ocular Trauma and Additional Ocular Findings

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Mehmet Giray Ersöz

2014-01-01

Full Text Available Objectives: To investigate the frequency of angle recession, commotio retinae, and other ocular findings in patients with hyphema due to blunt ocular trauma. Materials and Methods: The medical records of 66 patients hospitalized between July 2010 and May 2012 with a diagnosis of traumatic hyphema were retrospectively reviewed. The age, gender, period between injury and the first examination, visual acuity at presentation, intraocular pressure (IOP, time of disappearance of hyphema, cause of blunt injury, additional ocular findings, medical and/or surgical treatment, follow-up time, and visual outcome were noted. Results: The mean age of the patients was 23.8±19.2 years. Males constituted the 83.3% of the whole group. Game-related injury (43.9% and work-related injury (22.7% were the most common causes of blunt trauma. The bead gun was the most common tool involved in injury. Angle recession was detected in 36 patients (54.5%. Development of secondary glaucoma was higher in the patients with angle recession (chi-square test, p<0.05. Commotio retinae was observed in 47% of patients. The mean visual acuity at presentation was 0.4±0.3, while at the last visit, it was 0.8±0.3. There was a statistically significant difference between baseline and final visual acuity (paired-samples t-test, p<0.001. Conclusion: Hyphema due to blunt ocular trauma is observed mostly in young men and children. The most common blunt ocular injuries are game-and work-related. Angle recession and commotio retinae are the main complications of blunt ocular trauma causing hyphema. In cases with blunt ocular trauma, the presence of hyphema makes it difficult to examine the anterior chamber angle and the fundus. It is important to perform these investigations at the earliest stage to manage the complications since commotio retinae and angle recession accompany many cases with hyphema. (Turk J Ophthalmol 2014; 44: 19-22

Ocular Effects of Sulfur Mustard

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Yunes Panahi

2013-06-01

Full Text Available Purpose: To review current knowledge about ocular effects of sulfur mustard (SM and the associated histopathologic findings and clinical manifestationsMethods: Literature review of medical articles (human and animal studies was accomplished using PubMed, Scopus and ISI databases. A total of 274 relevant articles in English were retrieved and reviewed thoroughly.Results: Eyes are the most sensitive organs to local toxic effects of mustard gas. Ocular injuries are mediated through different toxic mechanisms including: biochemical damages, biomolecular and gene expression modification, induction of immunologic and inflammatory reactions, disturbing ultrastructural architecture of the cornea, and long-lasting corneal denervation. The resulting ocular injuries can roughly be categorized into acute or chronic complications. Most of the patients recover from acute injuries, but a minority of victims will suffer from chronic ocular complications. Mustard gas keratopathy (MGK is a devastating late complication of SM intoxication that proceeds from limbal stem cell deficiency (LSCD.Conclusion: SM induces several different damaging changes in case of ocular exposure; hence leading to a broad spectrum of ocular manifestations in terms of severity, timing and form. Unfortunately, no effective strategy has been introduced yet to inhibit or restore these damaging changes.

Epidemiology of Ocular Toxoplasmosis

NARCIS (Netherlands)

Petersen, E.; Kijlstra, A.; Stanford, M.

2012-01-01

Retinal infection with Toxoplasma gondii is the most important cause of posterior uveitis, whereby prevalence and incidence of ocular symptoms after infection depend on socio-economic factors and the circulating parasite genotypes. Ocular toxoplasmosis is more common in South America, Central

Antifungal Rhizosphere Bacteria Can increase as Response to the Presence of Saprotrophic Fungi.

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Wietse de Boer

Full Text Available Knowledge on the factors that determine the composition of bacterial communities in the vicinity of roots (rhizosphere is essential to understand plant-soil interactions. Plant species identity, plant growth stage and soil properties have been indicated as major determinants of rhizosphere bacterial community composition. Here we show that the presence of saprotrophic fungi can be an additional factor steering rhizosphere bacterial community composition and functioning. We studied the impact of presence of two common fungal rhizosphere inhabitants (Mucor hiemalis and Trichoderma harzianum on the composition of cultivable bacterial communities developing in the rhizosphere of Carex arenaria (sand sedge in sand microcosms. Identification and phenotypic characterization of bacterial isolates revealed clear shifts in the rhizosphere bacterial community composition by the presence of two fungal strains (M. hiemalis BHB1 and T. harzianum PvdG2, whereas another M. hiemalis strain did not show this effect. Presence of both M. hiemalis BHB1 and T. harzianum PvdG2 resulted in a significant increase of chitinolytic and (in vitro antifungal bacteria. The latter was most pronounced for M. hiemalis BHB1, an isolate from Carex roots, which stimulated the development of the bacterial genera Achromobacter and Stenotrophomonas. In vitro tests showed that these genera were strongly antagonistic against M. hiemalis but also against the plant-pathogenic fungus Rhizoctonia solani. The most likely explanation for fungal-induced shifts in the composition of rhizosphere bacteria is that bacteria are being selected which are successful in competing with fungi for root exudates. Based on the results we propose that measures increasing saprotrophic fungi in agricultural soils should be explored as an alternative approach to enhance natural biocontrol against soil-borne plant-pathogenic fungi, namely by stimulating indigenous antifungal rhizosphere bacteria.

Evaluation of pathogenic fungi occurrence in traumatogenic structures of freshwater fish Avaliação da ocorrência de fungos patogênicos em estruturas traumatogênicas de peixes fluviais

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Fabio Caetano Oliveira Leme

2011-04-01

Full Text Available INTRODUCTION: Fungal infections in human skin, such as sporotrichosis, can occur after fish induced trauma. This work aimed to identify fungi in freshwater fish that are pathogenic to humans. METHODS: Extraction of dental arches from Serrassalmus maculatus (piranha and Hoplias malabaricus (wolf fish, stings from Pimelodus maculatus (mandis catfish, dorsal fin rays from Plagioscion spp. (corvina and Tilapia spp., for culture in Mycosel agar. Some cultures were submitted to DNA extraction for molecular identification by sequencing ITS-5.8S rDNA. RESULTS: Cultures identified most yeast as Candida spp., while sequencing also permitted the identification of Phoma spp. and Yarrowia lipolytica. CONCLUSIONS: While the search for S. schenckii was negative, the presence of fungus of the genera Phoma and Candida revealed the pathogenic potential of this infection route. The genus Phoma is involved in certain forms of phaeohyphomycosis, a subcutaneous mycosis caused by dematiaceous fungi, with reports of infections in human organs and systems. Traumatizing structures of some freshwater fish present pathogenic fungi and this may be an important infection route that must be considered in some regions of Brazil, since there are a large number of a fisherman in constant contact with traumatogenic fish.INTRODUÇÃO: Infecções fúngicas na pele humana (como a esporotricose podem se manifestar após traumatismos por peixes. O objetivo deste trabalho é procurar fungos patogênicos para o homem em peixes fluviais. MÉTODOS: Extração de arcadas dentárias Serrassalmus maculatus (piranha e Hoplias malabaricus (traíra, ferrões de Pimelodus maculatus (mandis, raios da nadadeira dorsal de Plagioscion spp. (corvina e Tilapia spp. para a realização do cultivo em agar Mycosel. Algumas culturas foram submetidas à extração de DNA para a identificação molecular pelo seqüenciamento da região ITS-5.8S do rDNA. RESULTADOS: As culturas mostraram que a maioria das

Evaluating Susceptibility to Commercial Fungicide of Endophytic Fungi Isolated from Roses (Rosa hybrida

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Ingrid Carolina Corredor Perilla

2007-01-01

Full Text Available Fungal endophytes have shown their potential as biocontrol agents; however, their application in commercial fields remains limited. Continuously applying fungicides to crops (specifically to roses may have harmful effects on endophyte growth. Endophytic fungi were isolated from R. hybrida and their susceptibility to fungicides regularly used for controlling important pathogens was analysed. This was performed in vitro, mixing several fungicide concentrations with standard medium for fungal endophytes; growth inhibition was then measured. The susceptibility of Botrytis cinerea (3015 strain, one of the most important pathogens affecting roses in Colombia, was also assessed using the same protocols. Active ingredients, such as boscalid, captan, iprodione and pyrimethanyl, showed susceptibility ranging from not sensitive (³73.75% to regularly sensitive (³48.75% - <61.25% for 45.45% of the fungal endophytes assessed. Endophytic fungi were highly susceptible to fungicides such as pyrimethanyl, carboxin plus thiram, fludioxonyl plus ciprodinyl and prochloraz. B. cinerea (3015 strain presented high susceptibility (<23.75% to fungicides such as pyrimethanyl, carboxin and thiram, fludioxonil and ciprodinyl, prochloraz. Although B. cinerea showed the greatest growth in controls, the endophytic fungi being assessed grew better in different media with fungicides. The results revealed some of these fungal endophytes’ potential for integrated pest management (IPM in roses in Colombia (3002, 3003, 3004, 3005 and 3006 strains, taking into account correct application time, application frequency and both fungal endophyte and fungicide dosage which may greatly limit fungal endophyte growth.

Natural occurrence of entomophthoroid fungi of aphid pests on Medicago sativa L. in Argentina

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Romina G Manfrino

Full Text Available Four species of entomophthoroid fungi, Pandora neoaphidis (Entomophthorales: Entomophthoraceae, Zoophthora radicans (Entomophthorales: Entomophthoraceae, Entomophthora planchoniana (Entomophthorales: Entomophthoraceae and Neozygites fresenii (Neozygitales: Neozygitaceae were found to infect Aphis craccivora, Therioaphis trifolii, and Acyrthosiphon pisum and unidentified species of Acyrthosiphon on lucerne in Argentina. Samples were collected from five sites (Ceres, Rafaela, Sarmiento, Monte Vera and Bernardo de Irigoyen in the province of Santa Fe. In this study, Zoophthora radicans was the most important pathogen and was recorded mainly on Acyrthosiphon sp. Zoophthora radicans was successfully isolated and maintained in pure cultures. This study is the first report of entomophthoroid fungi infecting lucerne (Medicago sativa L. aphids in Argentina.

[Microscopic soil fungi - bioindicators organisms contaminated soil].

Science.gov (United States)

Donerian, L G; Vodianova, M A; Tarasova, Zh E

In the paper there are considered methodological issues for the evaluation of soil biota in terms of oil pollution. Experimental studies have shown that under the exposure of a various levels of oil pollution meeting certain gradations of the state and optimal alteration in microbocenosis in sod-podzolic soils, there is occurred a transformation of structure of the complex of micromycetes and the accumulation of toxic species, hardly typical for podzolic soils - primarily represantatives of the genus Aspergillus (A.niger and A. versicolor), Paecilomyces (P.variotii Bainer), Trichoderma (T.hamatum), the genus of phytopathogens Fusarium (F.oxysporum), dermatophytes of genus Sporothrix (S. schenckii) and dark-colored melanin containing fungi of Dematiaceae family. Besides that there are presented data on the study of microbiocenosis of the urban soil, the urban soil differed from the zone soil, but shaped in similar landscape and climatic conditions, and therefore having a tendency to a similar response from the side of microorganisms inhabiting the soil. Isolated complex of soil microscopic fungi is described by many authors as a complex, characteristic for soils of megalopolises. This allowed authors of this work to suggest that in urban soils the gain in the occurrence of pathogenic species micromycetes also increases against a background of chronic, continuously renewed inflow of petroleum hydrocarbons from various sources of pollution. Because changes in the species composition of micromycetes occurred in accordance with the increasing load of oil, so far as microscopic soil fungi can be recommended as a bioindicator organisms for oil. In the article there is also provided information about the distinctive features of modern DNA identification method of soil microscopic fungi and accepted in our country methodology of isolation of micromycetes with the use of a nutrient Czapek medium.

[Descending ocular myopathy].

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de Freitas, M R; Nascimento, O J

1975-06-01

The case of a 23 years old female patient, with primary involvement of the extraocular and faringeal muscles without familiar history is reported. Electromyographic and muscular biopsy studies proved the myogenic nature of the process. A clinical comparison between the ocular myopathy and the descending ocular myopathy is made, the authors thinking that both of them would be variants of the same muscle disease.

The vaginal mycobiome: A contemporary perspective on fungi in women's health and diseases.

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Bradford, L Latéy; Ravel, Jacques

2017-04-03

Most of what is known about fungi in the human vagina has come from culture-based studies and phenotypic characterization of single organisms. Though valuable, these approaches have masked the complexity of fungal communities within the vagina. The vaginal mycobiome has become an emerging field of study as genomics tools are increasingly employed and we begin to appreciate the role these fungal communities play in human health and disease. Though vastly outnumbered by its bacterial counterparts, fungi are important constituents of the vaginal ecosystem in many healthy women. Candida albicans, an opportunistic fungal pathogen, colonizes 20% of women without causing any overt symptoms, yet it is one of the leading causes of infectious vaginitis. Understanding its mechanisms of commensalism and patho-genesis are both essential to developing more effective therapies. Describing the interactions between Candida, bacteria (such as Lactobacillus spp.) and other fungi in the vagina is funda-mental to our characterization of the vaginal mycobiome.

Responsiveness of entomopathogenic fungi to menadione-induced oxidative stress.

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Azevedo, Rosana F F; Souza, Roberta K F; Braga, Gilberto U L; Rangel, Drauzio E N

2014-12-01

Entomopathogenic fungi are predisposed to ROS induced by heat and UV-A radiation when outside the insect host. When inside the host, they are subject to phagocytic cells that generate ROS to eliminate invading pathogens. The oxidative stress tolerance of the entomopathogenic fungi Aschersonia aleyrodis (ARSEF 430 and 10276), Aschersonia placenta (ARSEF 7637), Beauveria bassiana (ARSEF 252), Isaria fumosorosea (ARSEF 3889), Lecanicillium aphanocladii (ARSEF 6433), Metarhizium acridum (ARSEF 324), Metarhizium anisopliae (ARSEF 5749), Metarhizium brunneum (ARSEF 1187 and ARSEF 5626), Metarhizium robertsii (ARSEF 2575), Tolypocladium cylindrosporum (ARSEF 3392), Tolypocladium inflatum (ARSEF 4877), and Simplicillium lanosoniveum (ARSEF 6430 and ARSEF 6651) was studied based on conidial germination on a medium supplemented with menadione. Conidial germination was evaluated 24 h after inoculation on potato dextrose agar (PDA) (control) or PDA supplemented with menadione. The two Aschersonia species (ARSEF 430, 7637, and 10276) were the most susceptible fungi, followed by the two Tolypocladium species (ARSEF 3392 and 4877) and the M. acridum (ARSEF 324). Metarhizium brunneum (ARSEF 5626) and M. anisopliae (ARSEF 5749) were the most tolerant isolates with MIC 0.28 mM. All fungal isolates, except ARSEF 5626 and ARSEF 5749, were not able to germinate at 0.20 mM. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Pathogenic Fungal Species Associated with Digestive System of Periplaneta americana (Blattaria: Blattidae Trapped from Residential Dwellings in Ahvaz City, Southwestern Iran

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Hamid Kassiri

2018-03-01

Full Text Available Background: Cockroaches are the most prevalent domestic pests of a worldwide distribution. They were recognized as possible vectors of pathogenic bacteria, viruses, fungi and parasites in residential dwellings and hospital environ­ments. The present study isolated and identified yeasts and filamentous fungi from digestive tract of American cock­roaches, collected from three different residential regions of Iran.Methods: Seventy cockroaches were sampled using direct collection (hand catch, vacuum cleaner and sticky traps in Ahvaz, Iran in 2009–2010. Their medically important fungal microorganisms were isolated from digestive tract using standard mycological methods. Filamentous fungi were identified by macroscopic and microscopic examina­tion. Yeasts were identified by API ID32C-32100 kit.Results: A high percentage of cockroaches (88.6% were detected to carry fungi of medical importance. Overall, 23 fungi species/genera were isolated from the American cockroaches' alimentary tract. The fungi isolated from cock­roaches, from the residential regions were species of Aspergillus, Rhizopus, Penicillium, Mucorales, Alternaria, Cladosporium, Mycelia, Chrysosporium, Candida, Rhodotorula, Zygosaccharomyces, and Debaryomyces. Candida spp. (41.4%, Aspergillus spp. (37.1% and Rhodotorula spp (27.1% were the most common fungi recovered on cockroaches. Candida albicans and Candida glabrata were the commonest species of the genus Candida. In addi­tion, Aspergillus niger and A. flavus were the most frequent species of the genus Aspergillus.Conclusion: American cockroaches may carry pathogenic fungi in the urban areas of Ahvaz.

Ocular Perfusion Pressure and Pulsatile Ocular Blood Flow in Normal and Systemic Hypertensive Patients.

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Kanadani, Fabio N; Figueiredo, Carlos R; Miranda, Rafaela Morais; Cunha, Patricia Lt; M Kanadani, Tereza Cristina; Dorairaj, Syril

2015-01-01

Glaucomatous neuropathy can be a consequence of insufficient blood supply, increase in intraocular pressure (IOP), or other risk factors that diminish the ocular blood flow. To determine the ocular perfusion pressure (OPP) in normal and systemic hypertensive patients. One hundred and twenty-one patients were enrolled in this prospective and comparative study and underwent a complete ophthalmologic examination including slit lamp examination, Goldmann applanation tonometry, stereoscopic fundus examination, and pulsatile ocular blood flow (POBF) measurements. The OPP was calculated as being the medium systemic arterial pressure (MAP) less the IOP. Only right eye values were considered for calculations using Student's t-test. The mean age of the patients was 57.5 years (36-78), and 68.5% were women. There was a statistically significant difference in the OPP of the normal and systemic hypertensive patients (p cite this article: Kanadani FN, Figueiredo CR, Miranda RM, Cunha PLT, Kanadani TCM, Dorairaj S. Ocular Perfusion Pressure and Pulsatile Ocular Blood Flow in Normal and Systemic Hypertensive Patients. J Curr Glaucoma Pract 2015;9(1):16-19.

Antagonistic Potential of Native Trichoderma viride Strain against Potent Tea Fungal Pathogens in North East India.

Science.gov (United States)

Naglot, A; Goswami, S; Rahman, I; Shrimali, D D; Yadav, Kamlesh K; Gupta, Vikas K; Rabha, Aprana Jyoti; Gogoi, H K; Veer, Vijay

2015-09-01

Indigenous strains of Trichoderma species isolated from rhizosphere soils of Tea gardens of Assam, north eastern state of India were assessed for in vitro antagonism against two important tea fungal pathogens namely Pestalotia theae and Fusarium solani. A potent antagonist against both tea pathogenic fungi, designated as SDRLIN1, was selected and identified as Trichoderma viride. The strain also showed substantial antifungal activity against five standard phytopathogenic fungi. Culture filtrate collected from stationary growth phase of the antagonist demonstrated a significantly higher degree of inhibitory activity against all the test fungi, demonstrating the presence of an optimal blend of extracellular antifungal metabolites. Moreover, quantitative enzyme assay of exponential and stationary culture filtrates revealed that the activity of cellulase, β-1,3-glucanase, pectinase, and amylase was highest in the exponential phase, whereas the activity of proteases and chitinase was noted highest in the stationary phase. Morphological changes such as hyphal swelling and distortion were also observed in the fungal pathogen grown on potato dextrose agar containing stationary phase culture filtrate. Moreover, the antifungal activity of the filtrate was significantly reduced but not entirely after heat or proteinase K treatment, demonstrating substantial role of certain unknown thermostable antifungal compound(s) in the inhibitory activity.

Antagonistic Potential of Native Trichoderma viride Strain against Potent Tea Fungal Pathogens in North East India

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A. Naglot

2015-09-01

Full Text Available Indigenous strains of Trichoderma species isolated from rhizosphere soils of Tea gardens of Assam, north eastern state of India were assessed for in vitro antagonism against two important tea fungal pathogens namely Pestalotia theae and Fusarium solani. A potent antagonist against both tea pathogenic fungi, designated as SDRLIN1, was selected and identified as Trichoderma viride. The strain also showed substantial antifungal activity against five standard phytopathogenic fungi. Culture filtrate collected from stationary growth phase of the antagonist demonstrated a significantly higher degree of inhibitory activity against all the test fungi, demonstrating the presence of an optimal blend of extracellular antifungal metabolites. Moreover, quantitative enzyme assay of exponential and stationary culture filtrates revealed that the activity of cellulase, β-1,3-glucanase, pectinase, and amylase was highest in the exponential phase, whereas the activity of proteases and chitinase was noted highest in the stationary phase. Morphological changes such as hyphal swelling and distortion were also observed in the fungal pathogen grown on potato dextrose agar containing stationary phase culture filtrate. Moreover, the antifungal activity of the filtrate was significantly reduced but not entirely after heat or proteinase K treatment, demonstrating substantial role of certain unknown thermostable antifungal compound(s in the inhibitory activity.

Ecological niche of plant pathogens

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Ecaterina Fodor

2011-06-01

Full Text Available Disease ecology is a new approach to the understanding of the spread and dynamics of pathogens in natural and man-made environments. Defining and describing the ecological niche of the pathogens is one of the major tasks for ecological theory, as well as for practitioners preoccupied with the control and forecasting of established and emerging diseases. Niche theory has been periodically revised, not including in an explicit way the pathogens. However, many progresses have been achieved in niche modeling of disease spread, but few attempts were made to construct a theoretical frame for the ecological niche of pathogens. The paper is a review of the knowledge accumulated during last decades in the niche theory of pathogens and proposes an ecological approach in research. It quest for new control methods in what concerns forest plant pathogens, with a special emphasis on fungi like organisms of the genus Phytophthora. Species of Phytophthora are the most successful plant pathogens of the moment, affecting forest and agricultural systems worldwide, many of them being invasive alien organisms in many ecosystems. The hyperspace of their ecological niche is defined by hosts, environment and human interference, as main axes. To select most important variables within the hyperspace, is important the understanding of the complex role of pathogens in the ecosystems as well as for control programs. Biotic relationships within ecosystem of host-pathogen couple are depicted by ecological network and specific metrics attached to this. The star shaped network is characterized by few high degree nodes, by short path lengths and relatively low connectivity, premises for a rapid disturbance spread. 

Ecological niche of plant pathogens

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Ecaterina Fodor

2011-02-01

Full Text Available Disease ecology is a new approach to the understanding of the spread and dynamics of pathogens in natural and man-made environments. Defining and describing the ecological niche of the pathogens is one of the major tasks for ecological theory, as well as for practitioners preoccupied with the control and forecasting of established and emerging diseases. Niche theory has been periodically revised, not including in an explicit way the pathogens. However, many progresses have been achieved in niche modeling of disease spread, but few attempts were made to construct a theoretical frame for the ecological niche of pathogens. The paper is a review of the knowledge accumulated during last decades in the niche theory of pathogens and proposes an ecological approach in research. It quest for new control methods in what concerns forest plant pathogens, with a special emphasis on fungi like organisms of the genus Phytophthora. Species of Phytophthora are the most successful plant pathogens of the moment, affecting forest and agricultural systems worldwide, many of them being invasive alien organisms in many ecosystems. The hyperspace of their ecological niche is defined by hosts, environment and human interference, as main axes. To select most important variables within the hyperspace, is important for the understanding of the complex role of pathogens in the ecosystems as well as for control programs. Biotic relationships within ecosystem of host-pathogen couple are depicted by ecological network and specific metrics attached to this. The star shaped network is characterized by few high degree nodes, by short path lengths and relatively low connectivity, premises for a rapid disturbance spread.

A drug-sensitive genetic network masks fungi from the immune system.

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Robert T Wheeler

2006-04-01

Full Text Available Fungal pathogens can be recognized by the immune system via their beta-glucan, a potent proinflammatory molecule that is present at high levels but is predominantly buried beneath a mannoprotein coat and invisible to the host. To investigate the nature and significance of "masking" this molecule, we characterized the mechanism of masking and consequences of unmasking for immune recognition. We found that the underlying beta-glucan in the cell wall of Candida albicans is unmasked by subinhibitory doses of the antifungal drug caspofungin, causing the exposed fungi to elicit a stronger immune response. Using a library of bakers' yeast (Saccharomyces cerevisiae mutants, we uncovered a conserved genetic network that is required for concealing beta-glucan from the immune system and limiting the host response. Perturbation of parts of this network in the pathogen C. albicans caused unmasking of its beta-glucan, leading to increased beta-glucan receptor-dependent elicitation of key proinflammatory cytokines from primary mouse macrophages. By creating an anti-inflammatory barrier to mask beta-glucan, opportunistic fungi may promote commensal colonization and have an increased propensity for causing disease. Targeting the widely conserved gene network required for creating and maintaining this barrier may lead to novel broad-spectrum antimycotics.

Fungal diversity and potential tree pathogens in decaying logs and stumps

NARCIS (Netherlands)

Wal, van der Annemieke; klein Gunnewiek, Paulien; Hollander, de Mattias; Boer, de Wietse

2017-01-01

Different types of dead wood in forest ecosystems contribute to an increase of habitats for decomposer fungi. This may have a positive effect on fungal diversity but may also increase habitats for tree pathogens. In this study we investigate the fungal diversity and composition via high-throughput

Endophytic fungi from Myrcia guianensis at the Brazilian Amazon: distribution and bioactivity.

Science.gov (United States)

Dos Banhos, Elissandro Fonseca; de Souza, Antonia Queiroz Lima; de Andrade, Juliano Camurça; de Souza, Afonso Duarte Leão; Koolen, Hector Henrique Ferreira; Albuquerque, Patrícia Melchionna

2014-01-01

Beneficial interactions between plants and microorganisms have been investigated under different ecological, physiological, biochemical, and genetic aspects. However, the systematic exploration of biomolecules with potential for biotechnological products from this interaction still is relatively scarce. Therefore, this study aimed the evaluation of the diversity and antimicrobial activity of the endophytic fungi obtained from roots, stems and leafs of Myrcia guianensis (Myrtaceae) from the Brazilian Amazon. 156 endophytic fungi were isolated and above 80% were identified by morphological examination as belonging to the genera Pestalotiopsis, Phomopsis, Aspergillus, Xylaria, Nectria, Penicillium and Fusarium. Fermented broth of those fungi were assayed for antimicrobial activity and four inhibited the growth of Staphylococcus aureus, Enterococcus faecalis, Candida albicans and Penicillium avellaneum. As the strain named MgRe2.2.3B (Nectria haematococca) had shown the most promising results against those pathogenic strains, its fermented broth was fractioned and only its two low polar fractions demonstrated to be active. Both fractions exhibited a minimum bactericidal concentration of 50 μg.mL(-1) against S. aureus and a minimum fungicidal concentration of 100 μg.mL(-1) against P. avellaneum. These results demonstrate the diversity of fungal genera in M. guianensis and the potential of these endophytic fungi for the production of new antibiotics.

CEREALS ASSESSMENT TOWARDS CONTAMINATION OF PHYTOPATHOGENIC FUNGI IN FOREST-STEPPE AREA OF UKRAINE

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Yekimova V. B.

2014-12-01

Full Text Available The usage of high-quality seed, not affected by pathogens and fungi promote the high and stable yields. The condition of seeds determines their germination, seedling damage and adult plants, which ultimately affects the yield and on their quality. The significant risk of seed infection was registered in years with high humidity in the pre-harvest and harvest period. Therefore, along with the traditional seed control it is necessary to conduct phytopahtology expertise, allowing to identify the species composition of the microflora of seeds and the degree of infection with different pathogens. Smut disease - a solid and loose smut of wheat, hard and loose smut of barley - cause crop losses are clear - in the form of the destruction of the ear, and hidden - in the form of a reduction in seed germination, reduce winter hardiness, plant growth inhibition. Pathogens root rot causing blight, Fusarium and Helminthosporium that insignificantly demand on environmental conditions and extremely plastic. They have large set of enzymes that can exist on a variety of substrates, and therefore are widely distributed in nature and cause considerable damage to crops. Especially significant losses occur if the humidity during the ripening grain observed for several seasons, which leads to accumulation of the infection naturally. The aim of research was to assess the contamination of grain of spring wheat and barley phytopathogenic fungi in one of the main grain regions of Ukraine - the southern forest. The research conducted during the summer 2014 and compared with the results of previous years. Samples were taken from different plots. Seed contamination of samples by various phytopathogenic fungi was determined by the number of infected kernels per 100 seed sample. Frequency of registered species was recorded. For every studied sample we set the percentage of species. Analysis of the grain on the fungal infection and avdelenie in pure culture was performed

CEREALS ASSESSMENT TOWARDS CONTAMINATION OF PHYTOPATHOGENIC FUNGI IN FOREST-STEPPE AREA OF UKRAINE

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V. B. Yekimova

2014-11-01

Full Text Available The usage of high-quality seed, not affected by pathogens and fungi promote the high and stable yields. The condition of seeds determines their germination, seedling damage and adult plants, which ultimately affects the yield and on their quality. The significant risk of seed infection was registered in years with high humidity in the pre-harvest and harvest period. Therefore, along with the traditional seed control it is necessary to conduct phytopahtology expertise, allowing to identify the species composition of the microflora of seeds and the degree of infection with different pathogens. Smut disease - a solid and loose smut of wheat, hard and loose smut of barley - cause crop losses are clear - in the form of the destruction of the ear, and hidden - in the form of a reduction in seed germination, reduce winter hardiness, plant growth inhibition. Pathogens root rot causing blight, Fusarium and Helminthosporium that insignificantly demand on environmental conditions and extremely plastic. They have large set of enzymes that can exist on a variety of substrates, and therefore are widely distributed in nature and cause considerable damage to crops. Especially significant losses occur if the humidity during the ripening grain observed for several seasons, which leads to accumulation of the infection naturally. The aim of research was to assess the contamination of grain of spring wheat and barley phytopathogenic fungi in one of the main grain regions of Ukraine - the southern forest. The research conducted during the summer 2014 and compared with the results of previous years. Samples were taken from different plots. Seed contamination of samples by various phytopathogenic fungi was determined by the number of infected kernels per 100 seed sample. Frequency of registered species was recorded. For every studied sample we set the percentage of species. Analysis of the grain on the fungal infection and avdelenie in pure culture was performed

Botryosphaeria dothidea: a latent pathogen of global importance to woody plant health

NARCIS (Netherlands)

Marsberg, Angelica; Kemler, Martin; Jami, Fahimeh; Nagel, Jan H.; Postma-Smidt, Alisa; Naidoo, Sanushka; Wingfield, Michael J.; Crous, Pedro W.; Spatafora, Joseph W.; Hesse, Cedar N.; Robbertse, Barbara; Slippers, Bernard

Botryosphaeria dothidea is the type species of Botryosphaeria (Botryosphaeriaceae, Botryosphaeriales). Fungi residing in this order are amongst the most widespread and important canker and dieback pathogens of trees worldwide, with B. dothidea one of the most common species on a large number of

[Ocular surface system integrity].

Science.gov (United States)

Safonova, T N; Pateyuk, L S

2015-01-01

The interplay of different structures belonging to either the anterior segment of the eye or its accessory visual apparatus, which all share common embryological, anatomical, functional, and physiological features, is discussed. Explanation of such terms, as ocular surface, lacrimal functional unit, and ocular surface system, is provided.

Challenging ocular image recognition

Science.gov (United States)

Pauca, V. Paúl; Forkin, Michael; Xu, Xiao; Plemmons, Robert; Ross, Arun A.

2011-06-01

Ocular recognition is a new area of biometric investigation targeted at overcoming the limitations of iris recognition performance in the presence of non-ideal data. There are several advantages for increasing the area beyond the iris, yet there are also key issues that must be addressed such as size of the ocular region, factors affecting performance, and appropriate corpora to study these factors in isolation. In this paper, we explore and identify some of these issues with the goal of better defining parameters for ocular recognition. An empirical study is performed where iris recognition methods are contrasted with texture and point operators on existing iris and face datasets. The experimental results show a dramatic recognition performance gain when additional features are considered in the presence of poor quality iris data, offering strong evidence for extending interest beyond the iris. The experiments also highlight the need for the direct collection of additional ocular imagery.

MRI in ocular drug delivery

OpenAIRE

Li, S. Kevin; Lizak, Martin J.; Jeong, Eun-Kee

2008-01-01

Conventional pharmacokinetic methods for studying ocular drug delivery are invasive and cannot be conveniently applied to humans. The advancement of MRI technology has provided new opportunities in ocular drug-delivery research. MRI provides a means to non-invasively and continuously monitor ocular drug-delivery systems with a contrast agent or compound labeled with a contrast agent. It is a useful technique in pharmacokinetic studies, evaluation of drug-delivery methods, and drug-delivery de...

Chemical ecology of fungi.

Science.gov (United States)

Spiteller, Peter

2015-07-01

Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology.

Antibacterial Activity Symbiotic Fungi of Marine Sponge Axinella sp., Aspergillus Sydowii on Four Growth Medium

Science.gov (United States)

Widyaningsih, S.; Trianto, A.; Radjasa, OK; Wittriansyah, K.

2018-02-01

Many infectious diseases caused by Escherichia coli and Staphylococcus aureus which turned into a resistant pathogen. A symbiotic fungi of marine sponge Axinella sp., Aspergillus sydowii from the waters of Riung, East Nusa Tenggara, Indonesia showed antibacterial activity, cultured on the four media, MEB (ST), Noni Juice Media (MG), avocado leaves media (AL), and Soursop leaves media (SR). The symbiotic fungi was cultured for 14 days on each media. The largest weight of symbiotic fungi biomass on ST media 138,95gr and at least 99,12gr of AL media. Purification of bioactive compound is carried out using separatory funnel, and column chromatography. The highest rendemen of extracts on SR media was 3,67%, while the lowest in ST media was 1,22%. The bioactive test used diffusion agar method. Fungi extracts from four mediums have bioactivity against, E. coli and S. aureus. The biggest inhibition zone obtained from the extract of MG KN-15-3-1-3, with inhibition zone 10.71mm and 10.98mm against E. coli and S. aureus.

The role of strigolactones during plant interactions with the pathogenic fungus Fusarium oxysporum.

Science.gov (United States)

Foo, Eloise; Blake, Sara N; Fisher, Brendan J; Smith, Jason A; Reid, James B

2016-06-01

Strigolactones (SLs) do not influence spore germination or hyphal growth of Fusarium oxysporum. Mutant studies revealed no role for SLs but a role for ethylene signalling in defence against this pathogen in pea. Strigolactones (SLs) play important roles both inside the plant as a hormone and outside the plant as a rhizosphere signal in interactions with mycorrhizal fungi and parasitic weeds. What is less well understood is any potential role SLs may play in interactions with disease causing microbes such as pathogenic fungi. In this paper we investigate the influence of SLs on the hemibiotrophic pathogen Fusarium oxysporum f.sp. pisi both directly via their effects on fungal growth and inside the plant through the use of a mutant deficient in SL. Given that various stereoisomers of synthetic and naturally occuring SLs can display different biological activities, we used (+)-GR24, (-)-GR24 and the naturally occurring SL, (+)-strigol, as well as a racemic mixture of 5-deoxystrigol. As a positive control, we examined the influence of a plant mutant with altered ethylene signalling, ein2, on disease development. We found no evidence that SLs influence spore germination or hyphal growth of Fusarium oxysporum and that, while ethylene signalling influences pea susceptibility to this pathogen, SLs do not.

Importance of seed-borne fungi of sorghum and pearl millet in Burkina Faso and their control using plant extracts

DEFF Research Database (Denmark)

Zida, Elisabeth Pawindé; Sérémé, Paco; Leth, Vibeke

2008-01-01

recorded on each crop by the blotter test. Six essential oils of plants were investigated for their inhibitory activity against eight pathogenic fungi. Thirty four and 27 fungal species were found in seed samples of sorghum and pearl millet, respectively. Phoma sp. and Fusarium moniliforme infected 95...... of pearl millet, respectively. Seeds inoculated with Acremonium strictum, Curvularia oryzae, F. equiseti, F. moniliforme and F. subglutinans and sown in sterilized soil, showed considerable mortality of the seedlings. Three essential oils inhibited in vitro the mycelial growth of all the fungi used by 85......Seed-borne fungi of sorghum and pearl millet in Burkina Faso were surveyed. A total of 188 seed samples from various locations, collected in 1989 (42) and 2002 (146), were tested, using the blotter, dry inspection and washing methods. Infection experiments were carried out with the major fungi...

Ocular complications of boxing

Science.gov (United States)

Bianco, M; Vaiano, A; Colella, F; Coccimiglio, F; Moscetti, M; Palmieri, V; Focosi, F; Zeppilli, P; Vinger, P

2005-01-01

Objectives: To investigate the prevalence of ocular injuries in a large population of boxers over a period of 16 years, in particular, the most severe lesions that may be vision threatening. Methods: Clinical records of the medical archive of the Italian Boxing Federation were analysed. A total of 1032 boxers were examined from February 1982 to October 1998. A complete ophthalmological history was available for 956, who formed the study population (a total of 10 697 examinations). The following data were collected: age when started boxing; duration of competitive boxing career (from the date of the first bout); weight category; a thorough ocular history. The following investigations were carried out: measurement of visual acuity and visual fields, anterior segment inspection, applanation tonometry, gonioscopy, and examination of ocular fundus. Eighty age matched healthy subjects, who had never boxed, formed the control group. Results: Of the 956 boxers examined, 428 were amateur (44.8%) and 528 professional (55.2%). The median age at first examination was 23.1 (4.3) years (range 15–36). The prevalence of conjunctival, corneal, lenticular, vitreal, ocular papilla, and retinal alterations in the study population was 40.9% compared with 3.1% in the control group (p⩽0.0001). The prevalence of serious ocular findings (angle, lens, macula, and peripheral retina alterations) was 5.6% in boxers and 3.1% in controls (NS). Conclusions: Boxing does not result in a higher prevalence of severe ocular lesions than in the general population. However, the prevalence of milder lesions (in particular with regard to the conjunctiva and cornea) is noteworthy, justifying the need for adequate ophthalmological surveillance. PMID:15665199

Evaluating ocular blood flow

Directory of Open Access Journals (Sweden)

Jyotsna Maram

2017-01-01

Full Text Available Studies have shown that vascular impairment plays an important role in the etiology and pathogenesis of various ocular diseases including glaucoma, age-related macular degeneration, diabetic retinopathy, and retinal venous occlusive disease. Thus, qualitative and quantitative assessment of ocular blood flow (BF is a topic of interest for early disease detection, diagnosis, and management. Owing to the rapid improvement in technology, there are several invasive and noninvasive techniques available for evaluating ocular BF, with each of these techniques having their own limitations and advantages. This article reviews these important techniques, with a particular focus on Doppler Fourier domain optical coherence tomography (OCT and OCT-angiography.

Comparative Genomics of Smut Pathogens: Insights From Orphans and Positively Selected Genes Into Host Specialization

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Juliana Benevenuto

2018-04-01

Full Text Available Host specialization is a key evolutionary process for the diversification and emergence of new pathogens. However, the molecular determinants of host range are poorly understood. Smut fungi are biotrophic pathogens that have distinct and narrow host ranges based on largely unknown genetic determinants. Hence, we aimed to expand comparative genomics analyses of smut fungi by including more species infecting different hosts and to define orphans and positively selected genes to gain further insights into the genetics basis of host specialization. We analyzed nine lineages of smut fungi isolated from eight crop and non-crop hosts: maize, barley, sugarcane, wheat, oats, Zizania latifolia (Manchurian rice, Echinochloa colona (a wild grass, and Persicaria sp. (a wild dicot plant. We assembled two new genomes: Ustilago hordei (strain Uhor01 isolated from oats and U. tritici (strain CBS 119.19 isolated from wheat. The smut genomes were of small sizes, ranging from 18.38 to 24.63 Mb. U. hordei species experienced genome expansions due to the proliferation of transposable elements and the amount of these elements varied among the two strains. Phylogenetic analysis confirmed that Ustilago is not a monophyletic genus and, furthermore, detected misclassification of the U. tritici specimen. The comparison between smut pathogens of crop and non-crop hosts did not reveal distinct signatures, suggesting that host domestication did not play a dominant role in shaping the evolution of smuts. We found that host specialization in smut fungi likely has a complex genetic basis: different functional categories were enriched in orphans and lineage-specific selected genes. The diversification and gain/loss of effector genes are probably the most important determinants of host specificity.

[Progress in research on pathogenic genes and gene therapy for inherited retinal diseases].

Science.gov (United States)

Zhu, Ling; Cao, Cong; Sun, Jiji; Gao, Tao; Liang, Xiaoyang; Nie, Zhipeng; Ji, Yanchun; Jiang, Pingping; Guan, Minxin

2017-02-10

Inherited retinal diseases (IRDs), including retinitis pigmentosa, Usher syndrome, Cone-Rod degenerations, inherited macular dystrophy, Leber's congenital amaurosis, Leber's hereditary optic neuropathy are the most common and severe types of hereditary ocular diseases. So far more than 200 pathogenic genes have been identified. With the growing knowledge of the genetics and mechanisms of IRDs, a number of gene therapeutic strategies have been developed in the laboratory or even entered clinical trials. Here the progress of IRD research on the pathogenic genes and therapeutic strategies, particularly gene therapy, are reviewed.

Combat ocular trauma and systemic injury.

Science.gov (United States)

Weichel, Eric D; Colyer, Marcus H

2008-11-01

To review the recent literature regarding combat ocular trauma during hostilities in Operations Iraqi Freedom and Enduring Freedom, describe the classification of combat ocular trauma, and offer strategies that may assist in the management of eye injuries. Several recent publications have highlighted features of combat ocular trauma from Operation Iraqi Freedom. The most common cause of today's combat ocular injuries is unconventional fragmentary munitions causing significant blast injuries. These explosive munitions cause high rates of concomitant nonocular injuries such as traumatic brain injury, amputation, and other organ injuries. The most frequent ocular injuries include open-globe and adnexal lacerations. The extreme severity of combat-related open-globe injuries leads to high rates of primary enucleation and retained intraocular foreign bodies. Visual outcomes of intraocular foreign body injuries are similar to other series despite delayed removal, and no cases of endophthalmitis have occurred. Despite these advances, however, significant vision loss persists in cases of perforating globe injuries as well as open and closed-globe trauma involving the posterior segment. This review summarizes the recent literature describing ocular and systemic injuries sustained during Operations Iraqi and Enduring Freedom. An emphasis on classification of ocular injuries as well as a discussion of main outcome measures and complications is discussed.

Neurological and ocular fascioliasis in humans.

Science.gov (United States)

Mas-Coma, Santiago; Agramunt, Verónica H; Valero, María Adela

2014-01-01

Fascioliasis is a food-borne parasitic disease caused by the trematode species Fasciola hepatica, distributed worldwide, and Fasciola gigantica, restricted to given regions of Africa and Asia. This disease in humans shows an increasing importance, which relies on its recent widespread emergence related to climate and global changes and also on its pathogenicity in the invasive, biliary, and advanced chronic phases in the human endemic areas, mainly of developing countries. In spite of the large neurological affection capacity of Fasciola, this important pathogenic aspect of the disease has been pronouncedly overlooked in the past decades and has not even appear within the numerous reviews on the parasitic diseases of the central nervous system. The aim of this wide retrospective review is an in-depth analysis of the characteristics of neurological and ocular fascioliasis caused by these two fasciolid species. The terms of neurofascioliasis and ophthalmofascioliasis are restricted to cases in which the direct affection of the central nervous system or the eye by a migrant ectopic fasciolid fluke is demonstrated by an aetiological diagnosis of recovered flukes after surgery or spontaneous moving-out of the fluke through the orbit. Cases in which the ectopic fluke is not recovered and the symptoms cannot be explained by an indirect affection at distance may also be included in these terms. Neurofascioliasis and ophthalmofascioliasis cases are reviewed and discussed. With regard to fascioliasis infection giving an indirect rise to neurological affection, the distribution and frequency of cases are analysed according to geography, sex, and age. Minor symptoms and major manifestations are discussed. Three main types of cases are distinguished depending on the characteristics of their manifestations: genuine neurological, meningeal, and psychiatric or neuropsychic. The impressive symptoms and signs appearing in each type of these cases are included. Brain examination

Fatty Acid Methyl Ester (FAME) analyses for characterization and detection of grapevine pathogens

Science.gov (United States)

Grapevines can become infected by a variety of devastating pathogens, including the bacterium Xylella fastidiosa and canker fungi. Multiple strains of Xylella fastidiosa exist, each causing different diseases on various hosts. Although sequence-based genotyping can assist in distinguishing these str...

Comparative Genomics Yields Insights into Niche Adaptation of Plant Vascular Wilt Pathogens

NARCIS (Netherlands)

Klosterman, S.J.; Subbarao, K.V.; Kang, S.; Veronese, P.; Gold, S.E.; Thomma, B.P.H.J.; Chen, Z.J.; Henrissat, B.; Lee, Y.H.; Park, J.; Garcia-Pedrajas, M.D.; Barbara, D.J.; Anchieta, A.; Jonge, de R.; Santhanam, P.; Maruthachalam, K.; Atallah, Z.; Amyotte, S.G.; Paz, Z.; Inderbitzin, P.; Hayes, R.J.; Heiman, D.I.; Young, S.; Zeng, Q.; Engels, R.; Galagan, J.; Cuomo, C.; Dobinson, K.F.; Ma, L.J.

2011-01-01

The vascular wilt fungi Verticillium dahliae and V. albo-atrum infect over 200 plant species, causing billions of dollars in annual crop losses. The characteristic wilt symptoms are a result of colonization and proliferation of the pathogens in the xylem vessels, which undergo fluctuations in

Plasticity of the human otolith-ocular reflex

Science.gov (United States)

Wall, C. 3rd; Smith, T. R.; Furman, J. M.

1992-01-01

The eye movement response to earth vertical axis rotation in the dark, a semicircular canal stimulus, can be altered by prior exposure to combined visual-vestibular stimuli. Such plasticity of the vestibulo-ocular reflex has not been described for earth horizontal axis rotation, a dynamic otolith stimulus. Twenty normal human subjects underwent one of two types of adaptation paradigms designed either to attenuate or enhance the gain of the semicircular canal-ocular reflex prior to undergoing otolith-ocular reflex testing with horizontal axis rotation. The adaptation paradigm paired a 0.2 Hz sinusoidal rotation about a vertical axis with a 0.2 Hz optokinetic stripe pattern that was deliberately mismatched in peak velocity. Pre- and post-adaptation horizontal axis rotations were at 60 degrees/s in the dark and produced a modulation in the slow component velocity of nystagmus having a frequency of 0.17 Hz due to putative stimulation of the otolith organs. Results showed that the magnitude of this modulation component response was altered in a manner similar to the alteration in semicircular canal-ocular responses. These results suggest that physiologic alteration of the vestibulo-ocular reflex using deliberately mismatched visual and semicircular canal stimuli induces changes in both canal-ocular and otolith-ocular responses. We postulate, therefore, that central nervous system pathways responsible for controlling the gains of canal-ocular and otolith-ocular reflexes are shared.

Traumatismos oculares en el deporte

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Javier Elizalde

2007-06-01

Full Text Available Los traumatismos oculares durante la práctica deportiva son relativamente frecuentes, pueden acontecer en el contexto de cualquier deporte y son muy variados, tanto en su origen, gravedad y forma de presentación clínica (traumatismos incisos, contusos o inciso-contusos. A pesar de que el diagnóstico precoz y un tratamiento adecuado a cargo de un oftalmólogo especialista suele ayudar a mejorar el pronóstico de estos casos, es cierto que en algunas situaciones las lesiones oculares secundarias al traumatismo son clínicamente irreversibles. El autor revisa la repercusión clínica ocular de los accidentes deportivos con compromiso de la órbita, de los párpados, del segmento anterior y/o posterior del globo ocular, y de las vías ópticas. La mayoría de estas lesiones se pueden evitar optimizando el estado físico (y ocular antes de la práctica deportiva, y utilizando la técnica y el material adecuado para cada situación. Asimismo una buena educación deportiva desde la infancia y la utilización de gafas de protección ocular adaptadas a cada deporte juegan un papel esencial en la prevención de estos accidentes.

Molecular phylogeny, diversity and bioprospecting of endophytic fungi associated with wild ethnomedicinal North American plant Echinacea purpurea (Asteraceae)

Science.gov (United States)

The endophytic fungal community associated with the wild ethnomedicinal North American plant Echinacea purpurea was investigated as well as its potential for providing antifungal compounds against plant pathogenic fungi. A total of 233 endophytic fungal isolates were obtained and classified into 42 ...

Comparative genomics reveals mobile pathogenicity chromosomes in Fusarium

Energy Technology Data Exchange (ETDEWEB)

Ma, Li Jun; van der Does, H. C.; Borkovich, Katherine A.; Coleman, Jeffrey J.; Daboussi, Marie-Jose; Di Pietro, Antonio; Dufresne, Marie; Freitag, Michael; Grabherr, Manfred; Henrissat, Bernard; Houterman, Petra M.; Kang, Seogchan; Shim, Won-Bo; Wolochuk, Charles; Xie, Xiaohui; Xu, Jin Rong; Antoniw, John; Baker, Scott E.; Bluhm, Burton H.; Breakspear, Andrew; Brown, Daren W.; Butchko, Robert A.; Chapman, Sinead; Coulson, Richard; Coutinho, Pedro M.; Danchin, Etienne G.; Diener, Andrew; Gale, Liane R.; Gardiner, Donald; Goff, Steven; Hammond-Kossack, Kim; Hilburn, Karen; Hua-Van, Aurelie; Jonkers, Wilfried; Kazan, Kemal; Kodira, Chinnappa D.; Koehrsen, Michael; Kumar, Lokesh; Lee, Yong Hwan; Li, Liande; Manners, John M.; Miranda-Saavedra, Diego; Mukherjee, Mala; Park, Gyungsoon; Park, Jongsun; Park, Sook Young; Proctor, Robert H.; Regev, Aviv; Ruiz-Roldan, M. C.; Sain, Divya; Sakthikumar, Sharadha; Sykes, Sean; Schwartz, David C.; Turgeon, Barbara G.; Wapinski, Ilan; Yoder, Olen; Young, Sarah; Zeng, Qiandong; Zhou, Shiguo; Galagan, James; Cuomo, Christina A.; Kistler, H. Corby; Rep, Martijn

2010-03-18

Fusarium species are among the most important phytopathogenic and toxigenic fungi, having significant impact on crop production and animal health. Distinctively, members of the F. oxysporum species complex exhibit wide host range but discontinuously distributed host specificity, reflecting remarkable genetic adaptability. To understand the molecular underpinnings of diverse phenotypic traits and their evolution in Fusarium, we compared the genomes of three economically important and phylogenetically related, yet phenotypically diverse plant-pathogenic species, F. graminearum, F. verticillioides and F. oxysporum f. sp. lycopersici. Our analysis revealed greatly expanded lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes, accounting for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity. Experimentally, we demonstrate for the first time the transfer of two LS chromosomes between strains of F. oxysporum, resulting in the conversion of a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in the F. oxysporum species complex, putting the evolution of fungal pathogenicity into a new perspective.

Phylogeny of Alternaria fungi known to produce host-specific toxins on the basis of variation in internal transcribed spacers of ribosomal DNA.

Science.gov (United States)

Kusaba, M; Tsuge, T

1995-10-01

The internal transcribed spacer regions (ITS1 and ITS2) of ribosomal DNA from Alternaria species, including seven fungi known to produce host-specific toxins, were analyzed by polymerase chain reaction-amplification and direct sequencing. Phylogenetic analysis of the sequence data by the Neighbor-joining method showed that the seven toxin-producing fungi belong to a monophyletic group together with A. alternata. In contract, A. dianthi, A. panax, A. dauci, A. bataticola, A. porri, A. sesami and A. solani, species that can be morphologically distinguished from A. alternata, could be clearly separated from A. alternata by phylogenetic of the ITS variation. These results suggest that Alternaria pathogens which produce host-specific toxins are pathogenic variants within a single variable species, A. alternata.

Antifungal activity of saponins originated from Medicago hybrida against some ornamental plant pathogens

Directory of Open Access Journals (Sweden)

Alicja Saniewska

2012-12-01

Full Text Available Antifungal activity of total saponins originated from roots of Medicago hybrida (Pourret Trautv. were evaluated in vitro against six pathogenic fungi and eight individual major saponin glycosides were tested against one of the most susceptible fungi. The total saponins showed fungitoxic effect at all investigated concentrations (0.01%, 0.05% and 0.1% but their potency was different for individual fungi. The highest saponin concentration (0.1% was the most effective and the inhibition of Fusarium oxysporum f. sp. callistephi, Botrytis cinerea, Botrytis tulipae, Phoma narcissi, Fusarium oxysporum f. sp. narcissi was 84.4%, 69.9%, 68.6%, 57.2%, 55.0%, respectively. While Fusarium oxysporum Schlecht., a pathogen of Muscari armeniacum, was inhibited by 9.5% only. Eight major saponin glycosides isolated from the total saponins of M. hybrida roots were tested against the mycelium growth of Botrytis tulipae. The mycelium growth of the pathogen was greatly inhibited by hederagenin 3-O-β-D-glucopyranoside and medicagenic acid 3-O-β-D-glucopyranoside. Medicagenic acid 3-O-β-D-glucuronopyranosyl-28-O-β-D-glucopyranoside and oleanolic acid 3-O-[β-D-glucuronopyranosyl(1→2-α-L-galactopyranosyl]-28-O-β-D-glucopyranoside showed low fungitoxic activity. Medicagenic acid 3-O-a-D-glucopyranosyl- 28-O-β-D-glucopyranoside, hederagenin 3-O-[α-L- hamnopyranosyl(1→2-β-D-glucopyranosyl(1→2-β-D-glucopyranosyl]- 28-O-α-D-glucopyranoside and hederagenin 3-O-β-D-glucuronopyranosyl-28-O-β-D- lucopyranoside did not limit or only slightly inhibited growth of the tested pathogen. While 2β, 3β-dihydroxyolean-12 ene-23-al-28-oic acid 3-O-β-D-glucuronopyranosyl-28-O-β-D-glucopyranoside slightly stimulated mycelium growth of B. tulipae.

What Is an Ocular Migraine?

Science.gov (United States)

... When to seek help What is an ocular migraine? Is it a sign of something serious? Answers ... and retinal migraine, which could signal something serious. Migraine aura affecting your vision Ocular migraine sometimes describes ...

78 FR 35155 - Establishing a List of Qualifying Pathogens Under the Food and Drug Administration Safety and...

Science.gov (United States)

2013-06-12

... is thought to be a chromosomally encoded mutation in the target enzyme, although alternative... of qualifying pathogens. E. Candida Species Candida species are fungi (specifically, yeast) that are...

Characterization and isolation of an extracellular serine protease from the tomato pathogen Colletotrichum coccodes, and it's role in pathogenicity

Science.gov (United States)

Redman, Regina S.; Rodriguez, Rusty J.

2002-01-01

Extracellular enzymes play an important role in the pathogenicity and virulence of phytopathogenic fungi. Several isolates of Colletotrichum coccodes causal agent of anthracnose on tomato, were screened to determine the relationship between protease activity and virulence. A direct relationship was observed between extracellular protease activity and the induction of disease symptoms of fruit and mortality in plants. Isolate Cc155 exhibited the highest protease activity after five days of growth in protease induction medium and produced an extracellular serine protease (sp78) that was 78 kDa, auto-degradative, glucose repressible, and non-glycosylated. To determine the role of sp78 in pathogenicity, a UV-induced extracellular protease deficient mutant (np155) was generated from the wildtype isolate Cc155. Np155 maintained growth rates comparable to Cc155 and produced wildtype levels of extracellular cellulase but did not produce extracellular protease. Unlike Cc155, np155 caused no disease symptoms on tomato fruit and 0% mortality on tomato seedlings. These results suggest that extracellular protease activity is required for pathogenicity and virulence of C. coccodes and that the elimination of protease activity transforms a virulent pathogen to a non-pathogenic endophyte.

Ocular manifestations of leptospirosis

Directory of Open Access Journals (Sweden)

Rathinam S

2005-01-01

Full Text Available Leptospiral uveitis is a common entity in tropical countries. Ocular manifestations are noted in the second phase of illness, but these remain under-diagnosed mainly because of the prolonged symptom-free period that separates the systemic manifestations from detection of ocular manifestations.Varying ophthalmic presentations and the intrinsic nature of different types of uveitis to mimic one another also challenge the accuracy of the diagnosis. Of the individual ocular signs, the combination of acute, non-granulomatous, panuveitis, hypopyon, vasculitis, optic disc edema, membranous vitreous opacities and absence of choroiditis or retinitis have high predictive value for the clinical diagnosis of leptospiral uveitis. Geographic location of the patient, occupation, socio-economic status, risk factors related to exposure, past history of fever or jaundice also aid in diagnosis.Steroids are the mainstay of treatment for leptospiral uveitis. Depending upon the severity and anatomical location of inflammatory lesion, topical, peri-ocular and/or systemic steroids are given. The prognosis is generally good, even when the inflammation is severe.

A fungal pathogen of amphibians, Batrachochytrium dendrobatidis, attenuates in pathogenicity with in vitro passages.

Science.gov (United States)

Langhammer, Penny F; Lips, Karen R; Burrowes, Patricia A; Tunstall, Tate; Palmer, Crystal M; Collins, James P

2013-01-01

Laboratory investigations into the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), have accelerated recently, given the pathogen's role in causing the global decline and extinction of amphibians. Studies in which host animals were exposed to Bd have largely assumed that lab-maintained pathogen cultures retained the infective and pathogenic properties of wild isolates. Attenuated pathogenicity is common in artificially maintained cultures of other pathogenic fungi, but to date, it is unknown whether, and to what degree, Bd might change in culture. We compared zoospore production over time in two samples of a single Bd isolate having different passage histories: one maintained in artificial media for more than six years (JEL427-P39), and one recently thawed from cryopreserved stock (JEL427-P9). In a common garden experiment, we then exposed two different amphibian species, Eleutherodactylus coqui and Atelopus zeteki, to both cultures to test whether Bd attenuates in pathogenicity with in vitro passages. The culture with the shorter passage history, JEL427-P9, had significantly greater zoospore densities over time compared to JEL427-P39. This difference in zoospore production was associated with a difference in pathogenicity for a susceptible amphibian species, indicating that fecundity may be an important virulence factor for Bd. In the 130-day experiment, Atelopus zeteki frogs exposed to the JEL427-P9 culture experienced higher average infection intensity and 100% mortality, compared with 60% mortality for frogs exposed to JEL427-P39. This effect was not observed with Eleutherodactylus coqui, which was able to clear infection. We hypothesize that the differences in phenotypic performance observed with Atelopus zeteki are rooted in changes of the Bd genome. Future investigations enabled by this study will focus on the underlying mechanisms of Bd pathogenicity.

A fungal pathogen of amphibians, Batrachochytrium dendrobatidis, attenuates in pathogenicity with in vitro passages.

Directory of Open Access Journals (Sweden)

Penny F Langhammer

Full Text Available Laboratory investigations into the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd, have accelerated recently, given the pathogen's role in causing the global decline and extinction of amphibians. Studies in which host animals were exposed to Bd have largely assumed that lab-maintained pathogen cultures retained the infective and pathogenic properties of wild isolates. Attenuated pathogenicity is common in artificially maintained cultures of other pathogenic fungi, but to date, it is unknown whether, and to what degree, Bd might change in culture. We compared zoospore production over time in two samples of a single Bd isolate having different passage histories: one maintained in artificial media for more than six years (JEL427-P39, and one recently thawed from cryopreserved stock (JEL427-P9. In a common garden experiment, we then exposed two different amphibian species, Eleutherodactylus coqui and Atelopus zeteki, to both cultures to test whether Bd attenuates in pathogenicity with in vitro passages. The culture with the shorter passage history, JEL427-P9, had significantly greater zoospore densities over time compared to JEL427-P39. This difference in zoospore production was associated with a difference in pathogenicity for a susceptible amphibian species, indicating that fecundity may be an important virulence factor for Bd. In the 130-day experiment, Atelopus zeteki frogs exposed to the JEL427-P9 culture experienced higher average infection intensity and 100% mortality, compared with 60% mortality for frogs exposed to JEL427-P39. This effect was not observed with Eleutherodactylus coqui, which was able to clear infection. We hypothesize that the differences in phenotypic performance observed with Atelopus zeteki are rooted in changes of the Bd genome. Future investigations enabled by this study will focus on the underlying mechanisms of Bd pathogenicity.

Follicular lymphoma of the ocular adnexal region

DEFF Research Database (Denmark)

Rasmussen, Peter Kristian; Ralfkiaer, E.; Prause, J.U.

2015-01-01

Purpose To characterize the clinicopathological features of follicular lymphoma of the ocular adnexal region. Methods Retrospective nation-based study of Danish patients with ocular adnexal follicular lymphoma from January 1st 1980 through December 31st 2009. Results Twenty-four patients...... with ocular adnexal follicular lymphoma were identified. Fourteen (58%) of the patients were females. The median age was 63 years (range: 42–96 years). Eleven (46%) of the patients had primary ocular adnexal lymphoma, seven (29%) had an ocular adnexal lesion in conjunction with a concurrent systemic lymphoma...... and six patients (25%) presented with an ocular adnexal relapse. The most frequently affected sites were the lacrimal gland (38%) and the orbit (33%). Thirteen patients (54%) presented with Ann Arbor stage IE lymphoma, four (17%) had stage IIE, two patients (8%) stage IIIE, and five patients (21%) had...

Complications of presumed ocular tuberculosis.

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Hamade, Issam H; Tabbara, Khalid F

2010-12-01

To determine the effect of steroid treatment on visual outcome and ocular complications in patients with presumed ocular tuberculosis. Retrospective review of patients with presumptive ocular tuberculosis. The clinical diagnosis was made based on ocular findings, positive purified protein derivative (PPD) testing of more than 15 mm induration, exclusion of other causes of uveitis and positive ocular response to anti-tuberculous therapy (ATT) within 4 weeks. Group 1 included patients who had received oral prednisone or subtenon injection of triamcinolone acetonide prior to ATT. Group 2 included patients who did not receive corticosteroid therapy prior to administration of ATT.   Among 500 consecutive new cases of uveitis encountered in 1997-2007 there were 49 (10%) patients with presumed ocular tuberculosis. These comprised 28 (57%) male and 21 (43%) female patients with a mean age of 45 years (range 12-76 years). Four (20%) patients in group 1 had initial visual acuity of 20/40 or better, in comparison to eight (28%) patients in group 2. At 1-year follow-up, six (30%) patients in group 1 had a visual acuity of 20/40 or better compared with 20 (69%) patients in group 2 (p = 0.007). Of 20 eyes (26%) in group 1 that had visual acuity of < 20/50 at 1-year follow up, 14 (70%) eyes developed severe chorioretinal lesion (p = 0.019). Early administration of corticosteroids without anti-tuberculous therapy in presumed ocular tuberculosis may lead to poor visual outcome compared with patients who did not receive corticosteroids prior to presentation. Furthermore, the severity of chorioretinitis lesion in the group of patients given corticosteroid prior to ATT may account for the poor visual outcome. © 2009 The Authors. Journal compilation © 2009 Acta Ophthalmol.

The Plant Ribosome-Inactivating Proteins Play Important Roles in Defense against Pathogens and Insect Pest Attacks

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Feng Zhu

2018-02-01

Full Text Available Ribosome-inactivating proteins (RIPs are toxic N-glycosidases that depurinate eukaryotic and prokaryotic rRNAs, thereby arresting protein synthesis during translation. RIPs are widely found in various plant species and within different tissues. It is demonstrated in vitro and in transgenic plants that RIPs have been connected to defense by antifungal, antibacterial, antiviral, and insecticidal activities. However, the mechanism of these effects is still not completely clear. There are a number of reviews of RIPs. However, there are no reviews on the biological functions of RIPs in defense against pathogens and insect pests. Therefore, in this report, we focused on the effect of RIPs from plants in defense against pathogens and insect pest attacks. First, we summarize the three different types of RIPs based on their physical properties. RIPs are generally distributed in plants. Then, we discuss the distribution of RIPs that are found in various plant species and in fungi, bacteria, algae, and animals. Various RIPs have shown unique bioactive properties including antibacterial, antifungal, antiviral, and insecticidal activity. Finally, we divided the discussion into the biological roles of RIPs in defense against bacteria, fungi, viruses, and insects. This review is focused on the role of plant RIPs in defense against bacteria, fungi, viruses, and insect attacks. The role of plant RIPs in defense against pathogens and insects is being comprehended currently. Future study utilizing transgenic technology approaches to study the mechanisms of RIPs will undoubtedly generate a better comprehending of the role of plant RIPs in defense against pathogens and insects. Discovering additional crosstalk mechanisms between RIPs and phytohormones or reactive oxygen species (ROS against pathogen and insect infections will be a significant subject in the field of biotic stress study. These studies are helpful in revealing significance of genetic control that can

Monitoring of Soil-Borne Pathogens in the Agricultural Soils of the Pestrechinsky District (Tatarstan, Russia)

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Dzhabarova, K. O.; Kuryntseva, P. A.; Galitskaya, P. Y.; Selivanovskaya, S. Y.

2018-01-01

A recent agricultural trend is aimed to develop organic farming technologies. Organic farming means no mineral fertilizers, pesticides, antibiotics and other chemical substances not characteristic of natural conditions should be used in farm production. When choosing the regions, where this technology can be successfully realized, it is important to evaluate not only the physical and chemical qualities of soils, but also the degree of their infestation with phytopathogens. The Pestrechinsky District of the Republic of Tatarstan, where transfer to organic farming is being planned, was chosen as such a region. Agricultural lands were marked at the map of the administrative region, 100 sampling site were generated using GIS Technologies. It was found out that soil microbial community was characterized by a typical ratio and count of yeast fungi (3.4·105 - 1.6·106 CFU•g-1), mold fungi (1.0·101 - 1.7·105 CFU·g-1) and bacteria (1.6·106 - 3.1·107 CFU·g-1). In all the selected soil samples plant pathogenic fungi of the Fusarium genus were found (26 to 250 CFU·g-1), and as for another genus of plant pathogenic fungi, Alternaria, their count was rather low (0 to 9 CFU·g-1, herewith in 46 samples out of 100 they were absent.

Ocular allergy latin american consensus

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Myrna Serapião dos Santos

2011-12-01

Full Text Available PURPOSE: To establish current definition, classification and staging, and to develop diagnosis and treatment recommendations for ocular allergy, by using Delphi approach. METHODS: Ten Latin American experts on ocular allergy participated in a 4-round Delphi panel approach. Four surveys were constructed and answered by panelists. A two-thirds majority was defined as consensus. Definition, classification, staging and diagnosis and treatment recommendations were the main outcomes. RESULTS: "Ocular allergy" was proposed as the general term to describe ocular allergic diseases. Consensus regarding classification was not reached. Signs and symptoms were considered extremely important for the diagnosis. It was consensus that a staging system should be proposed based on the disease severity. Environmental control, avoidance of allergens and the use of artificial tears were recommended as first line treatment. The secondary treatment should include topical anti-histamines, mast cell stabilizers and multi actions drugs. Topical non-steroidal anti-inflammatory and vasoconstrictors were not recommended. Topical corticosteroids were recommended as third line of treatment for the most severe keratoconjunctivitis. Consensus was not reached regarding the use of systemic corticosteroids or immunosuppressant. Surgical approach and unconventional treatments were not recommended as routine. CONCLUSION: The task of creating guidelines for ocular allergies showed to be very complex. Many controversial topics remain unsolved. A larger consensus including experts from different groups around the world may be needed to further improve the current recommendations for several aspects of ocular allergy.

Ocular Manifestations of Acquired Immunodeficiency Syndrome.

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Kim, Young Shin; Sun, Hae Jung; Kim, Tae Hyong; Kang, Kui Dong; Lee, Sung Jin

2015-08-01

To investigate the patterns and risk factors of the ocular manifestations of acquired immunodeficiency syndrome (AIDS) and their correlation with CD4+ count in the era of highly active antiretroviral therapy (HAART). This retrospective study examined 127 AIDS patients who presented to Soonchunhyang University Hospital. Data were collected from patient interviews, clinical examinations, and laboratory investigations. Ophthalmologic examinations included the best-corrected visual acuity, intraocular pressure, anterior segment and adnexal examination, and dilated fundus examination. Of the 127 patients with AIDS, 118 were on HAART and 9 were not. The mean CD4+ count was 266.7 ± 209.1 cells/µL. There were ocular manifestations in 61 patients (48.0%). The incidence of anterior segment manifestations was higher than posterior segment manifestations at 28.3% and 19.7%, respectively. The mean CD4+ count was significantly (p AIDS. In this study, anterior segment and external ocular manifestations occurred more frequently than posterior segment manifestations. Also, the mean CD4+ count was significantly lower in patients with posterior segment ocular manifestations versus anterior segment ocular manifestations. We found that CD4+ count and age >35 years were independent risk factors for developing ocular manifestations.

Elucidation of biocontrol mechanisms of Trichoderma harzianum against different plant fungal pathogens: Universal yet host specific response.

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Sharma, Vivek; Salwan, Richa; Sharma, Prem N; Kanwar, S S

2017-02-01

In the present study, different transcripts of Trichoderma harzianum ThHP-3 were evaluated for their response against four fungal pathogens Fusarium oxysporum, Colletotrichum capsici, Colletotrichum truncatum and Gloesercospora sorghi using RT-qPCR. The time course study of T. harzianum transcripts related to signal transduction, lytic enzymes, secondary metabolites and various transporters revealed variation in expression against four fungal pathogens. In a broader term, the transcripts were upregulated at various time intervals but the optimum expression of cyp3, abc, nrp, tga1, pmk, ech42 and glh20 varied with respect to host fungi. Additionally, the expression of transcripts related to transporters/cytochromes was also observed against Fusarium oxysporum after 96h whereas transcripts related to secondary metabolites and lytic enzymes showed significant difference in expression against Colletotrichum spp. from 72 to 96h. This is first study on transcriptomic response of T. harzianum against pathogenic fungi which shows their host specific response. Copyright © 2016 Elsevier B.V. All rights reserved.

The Top 10 fungal pathogens in molecular plant pathology.

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Dean, Ralph; Van Kan, Jan A L; Pretorius, Zacharias A; Hammond-Kosack, Kim E; Di Pietro, Antonio; Spanu, Pietro D; Rudd, Jason J; Dickman, Marty; Kahmann, Regine; Ellis, Jeff; Foster, Gary D

2012-05-01

The aim of this review was to survey all fungal pathologists with an association with the journal Molecular Plant Pathology and ask them to nominate which fungal pathogens they would place in a 'Top 10' based on scientific/economic importance. The survey generated 495 votes from the international community, and resulted in the generation of a Top 10 fungal plant pathogen list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Magnaporthe oryzae; (2) Botrytis cinerea; (3) Puccinia spp.; (4) Fusarium graminearum; (5) Fusarium oxysporum; (6) Blumeria graminis; (7) Mycosphaerella graminicola; (8) Colletotrichum spp.; (9) Ustilago maydis; (10) Melampsora lini, with honourable mentions for fungi just missing out on the Top 10, including Phakopsora pachyrhizi and Rhizoctonia solani. This article presents a short resumé of each fungus in the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant mycology community, as well as laying down a bench-mark. It will be interesting to see in future years how perceptions change and what fungi will comprise any future Top 10. © 2012 THE AUTHORS. MOLECULAR PLANT PATHOLOGY © 2012 BSPP AND BLACKWELL PUBLISHING LTD.

Ocular findings in systemic lupus erythemato

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Samir S. Shoughy

2016-04-01

Full Text Available Systemic lupus erythematosus (SLE is a chronic multisystem autoimmune disease. Ocular complications occur in up to one-third of patients with SLE. The ocular findings may represent the initial manifestation of the disease and may lead to severe ocular morbidity and loss of vision. Early diagnosis and prompt management of patients with SLE are mandatory and require collaboration between the ophthalmologist and the rheumatologist.

Ocular findings in systemic lupus erythematosus.

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Shoughy, Samir S; Tabbara, Khalid F

2016-01-01

Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease. Ocular complications occur in up to one-third of patients with SLE. The ocular findings may represent the initial manifestation of the disease and may lead to severe ocular morbidity and loss of vision. Early diagnosis and prompt management of patients with SLE are mandatory and require collaboration between the ophthalmologist and the rheumatologist.

Structural and In Vivo Studies on Trehalose-6-Phosphate Synthase from Pathogenic Fungi Provide Insights into Its Catalytic Mechanism, Biological Necessity, and Potential for Novel Antifungal Drug Design

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Miao, Yi; Tenor, Jennifer L.; Toffaletti, Dena L.; Maskarinec, Stacey A.; Liu, Jiuyu; Lee, Richard E.; Perfect, John R.; Brennan, Richard G.; Hendrickson, Wayne A.

2017-07-25

The disaccharide trehalose is critical to the survival of pathogenic fungi in their human host. Trehalose-6-phosphate synthase (Tps1) catalyzes the first step of trehalose biosynthesis in fungi. Here, we report the first structures of eukaryotic Tps1s in complex with substrates or substrate analogues. The overall structures of Tps1 fromCandida albicansandAspergillus fumigatusare essentially identical and reveal N- and C-terminal Rossmann fold domains that form the glucose-6-phosphate and UDP-glucose substrate binding sites, respectively. These Tps1 structures with substrates or substrate analogues reveal key residues involved in recognition and catalysis. Disruption of these key residues severely impaired Tps1 enzymatic activity. Subsequent cellular analyses also highlight the enzymatic function of Tps1 in thermotolerance, yeast-hypha transition, and biofilm development. These results suggest that Tps1 enzymatic functionality is essential for the fungal stress response and virulence. Furthermore, structures of Tps1 in complex with the nonhydrolyzable inhibitor, validoxylamine A, visualize the transition state and support an internal return-like catalytic mechanism that is generalizable to other GT-B-fold retaining glycosyltransferases. Collectively, our results depict key Tps1-substrate interactions, unveil the enzymatic mechanism of these fungal proteins, and pave the way for high-throughput inhibitor screening buttressed and guided by the current structures and those of high-affinity ligand-Tps1 complexes.

IMPORTANCEInvasive fungal diseases have emerged as major threats, resulting in more than 1.5 million deaths annually worldwide. This epidemic has been further complicated by increasing resistance to all major classes of antifungal drugs in the clinic. Trehalose biosynthesis is essential for the fungal stress response and virulence. Critically, this biosynthetic pathway is absent in

Ocular and systemic pharmacokinetics of lidocaine hydrochloride ophthalmic gel in rabbits after topical ocular administration.

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Liu, Bing; Ding, Li; Xu, Xiaowen; Lin, Hongda; Sun, Chenglong; You, Linjun

2015-12-01

Lidocaine hydrochloride ophthalmic gel is a novel ophthalmic preparation for topical ocular anesthesia. The study is aimed at evaluating the ocular and systemic pharmacokinetics of lidocaine hydrochloride 3.5 % ophthalmic gel in rabbits after ocular topical administration. Thirty-six rabbits were randomly placed in 12 groups (3 rabbits per group). The rabbits were quickly killed according to their groups at 0 (predose), 0.0833, 0.167, 0.333, 0.667, 1, 1.5, 2, 3, 4, 6, and 8 h postdose and then the ocular tissue and plasma samples were collected. All the samples were analyzed by a validated LC-MS/MS method. The test result showed that the maximum concentration (C max) of lidocaine in different ocular tissues and plasma were all achieved within 20 min after drug administration, and the data of C max were (2,987 ± 1814) μg/g, (44.67 ± 12.91) μg/g, (26.26 ± 7.19) μg/g, (11,046 ± 2,734) ng/mL, and (160.3 ± 61.0) ng/mL for tear fluid, cornea, conjunctiva, aqueous humor, and plasma, respectively. The data of the elimination half-life in these tissues were 1.5, 3.2, 3.5, 1.9, and 1.7 h for tear fluid, cornea, conjunctiva, aqueous humor, and plasma, respectively. The intraocular lidocaine levels were significantly higher than that in plasma, and the elimination half-life of lidocaine in cornea, conjunctiva, and aqueous humor was relatively longer than that in tear fluid and plasma. The high intraocular penetration, low systemic exposure, and long duration in the ocular tissues suggested lidocaine hydrochloride 3.5 % ophthalmic gel as an effective local anesthetic for ocular anesthesia during ophthalmic procedures.

Hyphema as a Complication of Blunt Ocular Trauma and Additional Ocular Findings

OpenAIRE

Mehmet Giray Ersöz; Seda Adıyeke; Gamze Türe; Ekrem Talay; Hakkı Özgür Konya

2014-01-01

Objectives: To investigate the frequency of angle recession, commotio retinae, and other ocular findings in patients with hyphema due to blunt ocular trauma. Materials and Methods: The medical records of 66 patients hospitalized between July 2010 and May 2012 with a diagnosis of traumatic hyphema were retrospectively reviewed. The age, gender, period between injury and the first examination, visual acuity at presentation, intraocular pressure (IOP), time of disappearance of hyphem...

The distribution and symptomatology of grapevine trunk disease pathogens are influenced by climate

NARCIS (Netherlands)

van Niekerk, J.M.; Bester, W.; Halleen, F.; Crous, P.W.; Fourie, P.H.

2011-01-01

Grapevine trunk diseases, caused by a range of phytopathogenic fungi, represent a serious impediment to wine and table grape production wherever these crops are cultivated. Previous studies have shown that the distribution of these pathogens is influenced by climate and that they are associated with

Structural and In Vivo Studies on Trehalose-6-Phosphate Synthase from Pathogenic Fungi Provide Insights into Its Catalytic Mechanism, Biological Necessity, and Potential for Novel Antifungal Drug Design

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Yi Miao

2017-07-01

Full Text Available The disaccharide trehalose is critical to the survival of pathogenic fungi in their human host. Trehalose-6-phosphate synthase (Tps1 catalyzes the first step of trehalose biosynthesis in fungi. Here, we report the first structures of eukaryotic Tps1s in complex with substrates or substrate analogues. The overall structures of Tps1 from Candida albicans and Aspergillus fumigatus are essentially identical and reveal N- and C-terminal Rossmann fold domains that form the glucose-6-phosphate and UDP-glucose substrate binding sites, respectively. These Tps1 structures with substrates or substrate analogues reveal key residues involved in recognition and catalysis. Disruption of these key residues severely impaired Tps1 enzymatic activity. Subsequent cellular analyses also highlight the enzymatic function of Tps1 in thermotolerance, yeast-hypha transition, and biofilm development. These results suggest that Tps1 enzymatic functionality is essential for the fungal stress response and virulence. Furthermore, structures of Tps1 in complex with the nonhydrolyzable inhibitor, validoxylamine A, visualize the transition state and support an internal return-like catalytic mechanism that is generalizable to other GT-B-fold retaining glycosyltransferases. Collectively, our results depict key Tps1-substrate interactions, unveil the enzymatic mechanism of these fungal proteins, and pave the way for high-throughput inhibitor screening buttressed and guided by the current structures and those of high-affinity ligand-Tps1 complexes.

Biosensors for plant pathogen detection.

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Khater, Mohga; de la Escosura-Muñiz, Alfredo; Merkoçi, Arben

2017-07-15

Infectious plant diseases are caused by pathogenic microorganisms such as fungi, bacteria, viruses, viroids, phytoplasma and nematodes. Worldwide, plant pathogen infections are among main factors limiting crop productivity and increasing economic losses. Plant pathogen detection is important as first step to manage a plant disease in greenhouses, field conditions and at the country boarders. Current immunological techniques used to detect pathogens in plant include enzyme-linked immunosorbent assays (ELISA) and direct tissue blot immunoassays (DTBIA). DNA-based techniques such as polymerase chain reaction (PCR), real time PCR (RT-PCR) and dot blot hybridization have also been proposed for pathogen identification and detection. However these methodologies are time-consuming and require complex instruments, being not suitable for in-situ analysis. Consequently, there is strong interest for developing new biosensing systems for early detection of plant diseases with high sensitivity and specificity at the point-of-care. In this context, we revise here the recent advancement in the development of advantageous biosensing systems for plant pathogen detection based on both antibody and DNA receptors. The use of different nanomaterials such as nanochannels and metallic nanoparticles for the development of innovative and sensitive biosensing systems for the detection of pathogens (i.e. bacteria and viruses) at the point-of-care is also shown. Plastic and paper-based platforms have been used for this purpose, offering cheap and easy-to-use really integrated sensing systems for rapid on-site detection. Beside devices developed at research and development level a brief revision of commercially available kits is also included in this review. Copyright © 2016 Elsevier B.V. All rights reserved.

Histone Acetylation in Fungal Pathogens of Plants

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Junhyun Jeon

2014-03-01

Full Text Available Acetylation of histone lysine residues occurs in different organisms ranging from yeast to plants and mammals for the regulation of diverse cellular processes. With the identification of enzymes that create or reverse this modification, our understanding on histone acetylation has expanded at an amazing pace during the last two decades. In fungal pathogens of plants, however, the importance of such modification has only just begun to be appreciated in the recent years and there is a dearth of information on how histone acetylation is implicated in fungal pathogenesis. This review covers the current status of research related to histone acetylation in plant pathogenic fungi and considers relevant findings in the interaction between fungal pathogens and host plants. We first describe the families of histone acetyltransferases and deacetylases. Then we provide the cases where histone acetylation was investigated in the context of fungal pathogenesis. Finally, future directions and perspectives in epigenetics of fungal pathogenesis are discussed.

Expression Study of Banana Pathogenic Resistance Genes