Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FUNGI”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,423 records · Page 79Linked to original sources
PubMed1995

Filamentous soil fungi and unidentified bacteria in drinking water from wells and water mains near Bratislava.

The occurrence of filamentous fungi in 294 samples of drinking water taken from wells and taps near Bratislava was studied. Fungal contaminants were found in 192 samples (44%). 39 genera and 64 species of soil filamentous fungi were identified by routine isolation and cultivation methods. Most of them belong to the Deuteromycetes. In the course of fungal cultivation in Czapek-Dox agar supplemented with 20 mg.l-1 tetracycline, colonies of unknown yellow coloured bacteria were observed.

Bacteria↗
PubMed1994

[Characterization of fungi isolated from woody-chip piles, especially thermophilic and thermotolerant isolates].

Samples were taken in order to isolate fungi from four woodychip piles (three of these were treated with liquid manure) from different depths. 39 species of 121 isolates could be determined. They represent 28 genera. Aspergillus fumigatus, Trichoderma reseei, Corynascus sespedonium and Mucor hiemalis were isolated most frequently. The isolates were examined for their temperature requirements. Following the definitions of Hawskworth (1983) they could be classified into the three groups of "thermophilic" (28 isolates), "thermotolerant" (29 isolates) and "mesophilic" (64 isolates) fungi. The temperature requirements for sporulation were also examined. Partly sporulation could be observed within more restricted temperature borders than growth but optimal sporulation occurs within wider temperature areas than optimal growth. The optimal sporulation-temperature was defined as the temperature at which sporulation began fastest.

Fungi↗
PubMed1999

Lead mineral transformation by fungi.

Pyromorphite (Pb5(PO4)3Cl), the most stable lead mineral under a wide range of geochemical conditions [1], can form in urban and industrially contaminated soils [2] [3] [4] [5]. It has been suggested that the low solubility of this mineral could reduce the bioavailability of lead, and several studies have advocated pyromorphite formation as a remediation technique for lead-contaminated land [3] [5] [6], if necessary using addition of phosphate [6]. Many microorganisms can, however, make insoluble soil phosphate bioavailable [7] [8] [9] [10], and the solubilisation of insoluble metal phosphates by free-living and symbiotic fungi has been reported [11] [12] [13] [14] [15]. If pyromorphite can be solubilised by microbial phosphate-solubilising mechanisms, the question arises of what would happen to the released lead. We have now clearly demonstrated that pyromorphite can be solubilised by organic-acid-producing fungi, for example Aspergillus niger, and that plants grown with pyromorphite as sole phosphorus source take up both phosphorus and lead. We have also discovered the production of lead oxalate dihydrate by A. niger during pyromorphite transformation, which is the first recorded biogenic formation of this mineral. These mechanisms of lead solubilisation, or its immobilisation as a novel lead oxalate, have significant implications for metal mobility and transfer to other environmental compartments and organisms. The importance of considering microbial processes when developing remediation techniques for toxic metals in soils is therefore emphasised.

Aspergillus niger↗
PubMed2000

cAMP signalling in pathogenic fungi: control of dimorphic switching and pathogenicity.

Morphological changes in pathogenic fungi often underlie the development of virulence and infection by these organisms. Our knowledge of the components of the cell signalling pathways controlling morphological switching has, to a large extent, come from studies of pseudohyphal growth of the model organism Saccharomyces cerevisiae, in which control is exerted via changes in the intracellular cAMP and mitogen-activated protein kinase cascades. There is evidence that pathogenic fungi also utilize these pathways to control dimorphic switching between saprobic and pathogenic forms and, as such, the elements of these pathways have potential as drug targets.

Carbon↗
PubMed1999

The influence of dsRNA viruses on the biology of plant pathogenic fungi.

Double-stranded RNA viruses are ubiquitous in fungi. They are non-infective and, like most prokaryotic plasmids, are only transmitted to compatible strains via cell fusion. Most are cryptic, but some with an established phenotype, such as the hypoviruses of the chestnut-blight fungus, have been studied for their potential as biological control agents of fungi.

Fungi↗
PubMed2006

Clustered sensitivity to fungi: anaphylactic reactions caused by ingestive allergy to yeasts.

BACKGROUND: Respiratory allergy to environmental molds is relatively common, and fungal allergen-specific reactivity seems to cluster in certain persons. However, generalized reactions caused by ingested fungi have seldom been described. OBJECTIVE: To describe a mold-sensitized patient who developed multiple anaphylactic reactions after ingesting a yeast preparation widely used by the food industry as flavoring in, for example, powdered and ready-made sauces. METHODS: Skin prick tests and serum IgE tests were performed with inhalant and food allergens, including molds and yeasts, 2 pasta sauces consumed by the patient, individual sauce ingredients, and a food-quality yeast extract. Radioallergosorbent test inhibition was used for specificity studies. RESULTS: Skin prick and serum IgE test results were positive to several molds (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, and Penicillium notatum), baker's yeast (Saccharomyces cerevisiae), Malassezia furfur, and champignon and to the 2 pasta sauces, the yeast ingredient, and a food-quality yeast extract. Radioallergosorbent test inhibition studies confirmed that the sauces contain cross-reacting yeast and mold allergens. CONCLUSIONS: This patient has a clustered sensitization to fungi characterized by allergy to environmental fungal allergens and to yeast extracts used in the food industry. Yeasts should be considered as possible ingestive allergens in mold-allergic patients.

Adult↗
PubMed2001

Fungi: toxic killers or unavoidable nuisances?

OBJECTIVES: This discussion is focused on the many roles of fungi in human health, and also to put the mycotoxin literature into perspective. DATA SOURCES: Data are derived from the literature referenced in PubMed from the National Library of Medicine, earlier references in the authors' reprint collection, and ongoing research. Studies for review were either selected from the peer-reviewed literature or from standard texts that are well recognized in the field. RESULTS: The review yielded many studies of the role of fungi in allergic disease, but none that systematically documented such a role for mycotoxins or fungal volatiles. Many case studies were found, but none of these unequivocally document a cause/effect relationship between mycotoxin exposure by inhalation and human disease in residential, school, or office settings. CONCLUSIONS: The review led to the conclusion that that the primary result from fungal exposure is allergic disease, and that the evidence for inhalation disease resulting from mycotoxin exposure in residential and office settings is extremely weak.

Administration, Inhalation↗
PubMed2001

Fatty acid composition and dynamics of selected fungal-feeding nematodes and fungi.

Fatty acid profiles of fungal-feeding nematodes, Aphelenchus avenae and Aphelenchoides composticola, and selected fungi were determined in microcosm cultures of agar, broth, or sand amended with organic matter. Fatty acids of A. avenae and A. composticola included 16:0 18:0, 18:1omega7, 18:1omega9, 18:2, 20:0, 20:1, 20:2, 20:3 and 20:4 phospholipid fatty acids (PLFAs) and neutral lipid fatty acids (NLFAs). The nematodes differed in relative amounts of saturated and C(18) fatty acids. Similar C(16) and C(18) PLFAs and whole-cell fatty acids were found in Rhizoctonia solani, Fusarium oxysporum and Trichoderma sp. with 18:2omega6 as the major component. The C(20) fatty acids were not found in these fungi. Although only present in the nematodes, C(20) PLFAs were only detected when nematode population levels were > or =22 per gram of sand, suggesting that there is a detection threshold that might limit their use as biomarkers in the soil community. After removal of nematodes from a food source, the relative amount of C(20) PLFAs (structural components of nematode cell membranes) decreased more slowly than the C(16) and C(18) PLFAs, which may have reflected ingested fungal cytoplasm in the nematode intestine. In the early stage of organic matter decomposition, total and fungal PLFAs were lower in the presence of A. composticola then in its absence at C:N ratios > or =30:1.

Animals↗
PubMed2005

Isolation, identification and antifungal susceptibility of lemon pathogenic and non pathogenic fungi.

Numerous species of filamentous fungi were isolated from lemon on different plantations in the province of Tucuman, Argentina. The techniques suggested by the Subcommittee of Antifungal Susceptibility of the National Committee for Clinical Laboratory Standards, (USA) were adapted. The effect of three different concentrations of the fungicides imazalil, guazatine, SOPP and thiabendazole on the fungi Fusarium oxysporum, Fusarium moniliforme, Aspergillus niger, Aspergillus flavus, Aspergillus clavatus, Geotrichum candidum, Rhizopus sp, Penicillium sp, Penicillium digitatum and Mucor sp were studied. All the tested strains were resistant to thiabendazole. We assayed a mixture of SOPP (5%), guazatine (350 ppm) and imazalil (100 ppm), which showed a synergic effect on Rhizopus sp. Mucor sp was the only fungus resistant to the four fungicides tested as well as to the above mentioned mixture.

Aspergillus↗
PubMed2006

Fungi in bottled water: a case study of a production plant.

A one-year fungal survey of a water bottling plant was conducted in order to evaluate the incidence and fluctuations of the mycobiota. The dominant fungal genera in order of highest numbers isolated were Penicillium, Cladosporium and Trichoderma followed by Aspergillus, Paecilomyces, and others. As expected, the highest number of isolates were collected during the warmer months, particularly May and June. Indeed during these two months there were more fungi present in the water, indicating that during those times of the year when fungal contamination is high, 0.4 mm filters should be changed on a more regular basis. In order to assess whether contamination was single or multi-loci, molecular methods based on the PCR were used for Penicillium brevicompactum. Overall, fungal contamination arose from multiple sources. Some P. brevicompactum strains were very "alike" and were detected during different sampling times, indicating that they were endemic to the plant. There was no evidence to suggest that fungi detected in the source water passed through to other parts of the plant. However, there was evidence that fungal strains isolated from the water filter were detected elsewhere in the factory, confirming the need to change filters more regularly during periods of high fungal contamination. In order to improve quality control a HACCP programme was implemented and Best Practice Guidelines introduced.

Air Microbiology↗
PubMed2002

Genomics of parasitic and symbiotic fungi.

Complete and partial genome sequence information is underway in several parasitic and symbiotic fungi that infect humans, other animals and plants. Comparative analyses of these sequences will provide new insights into the genomic plasticity and evolution of parasitism and mutualism in fungi.

DNA, Fungal↗
PubMed1998

Insertional mutagenesis of pathogenic fungi.

Screening insertional mutants for loss of virulence is an effective method for investigating the molecular genetic basis of bacterial pathogenesis, but has only recently been applied to fungal pathogens. For many pathogenic fungi transformation with heterologous plasmid DNA results in complex integration events. This problem can now be circumvented for some species using restriction enzyme mediated integration. Insertional mutagenesis of Fusarium oxysporum using the naturally occurring fungal transposon impala has been described, but transposon tagging for other fungi has yet to be developed. Although insertional mutagenesis has recently identified important virulence determinants of fungal phytopathogens, the lack of suitable screening strategies has so far limited its applicability for fungal pathogens of humans.

Fungi↗
PubMed2007

Role of mini-host models in the study of medically important fungi.

Mini-host models have emerged as simple experimental systems to study the pathogenesis and host innate immune responses in fungal invaders and also to test drug efficacy against these organisms. A growing number of medically important fungi, including Aspergillus spp, Candida spp, Cryptococcus spp, and species in the class Zygomycetes, have been shown to infect and kill invertebrates such as roundworms, fruit flies, and wax moths. These studies have shown that several genes implicated in the virulence of fungi in mammalian models also have a similarly important pathogenic role in mini-host organisms. These mini-host models provide a unique opportunity of simultaneously exploring the molecular mechanisms of fungal pathogenicity and candidate agents with antifungal activity. Furthermore, the fact that some of these mini-hosts have well-defined genetics and conserved innate immunity offers the advantage of a comprehensive analysis of the molecular aspects of host immune response. We examine the relevance, advantages, and pitfalls of experimental systems of fungal infections in various mini-hosts and compare them with what is known in experimental systems in mammalian animal models.

Animals↗
PubMed1991

In vitro stress selection of nematophagous fungi for biocontrol of parasitic nematodes in ruminants.

Laboratory experiments were designed to select nematophagous fungi that were able to survive in vitro conditions simulating passage through the gastro-intestinal tract of cattle. All of the tests were conducted at 39 degrees C. In a primary stress selection step in diluted rumen fluid, 21 isolates were obtained. Each of the primary stress selected isolates was tested in synthetic saliva, rumen fluid simulating the activity in the rumen, rumen fluid followed by pepsin-hydrochloric acid treatment simulating the additional effect of ruminal and abomasal activity, pepsin-hydrochloric acid solution simulating conditions in the abomasum and finally in a trypsin solution as an example of enzyme activity in the gut. The effect of the rumen fluid alone, or rumen fluid followed by pepsin-hydrochloric acid treatment, were responsible for the reduction in surviving fungal isolates. Only six of thirteen isolates belonging to the genus Arthrobotrys survived while seven of eight isolates of the genus Duddingtonia survived. Fourteen isolates were tested for their predatory capacity in a dung pat bioassay. Fungi of the genera Arthrobotrys and Duddingtonia reduced the development of Ostertagia ostertagi third stage larvae by approximately 75% and 96% respectively compared to the number of larvae that developed from fungus-free control pats.

Animals↗
PubMed1993

Antagonistic effect of predacious Arthrobotrys fungi on infective Haemonchus placei larvae.

Laboratory experiments were performed to investigate the ability of isolates from the predacious fungus species Arthrobotrys conoides (one isolate) and Al. robusta (four isolates) to trap and kill infective Haemonchus placei larvae. Three groups for each isolate were formed: group 1, fungi and infective larvae; group 2, fungi; group 3, infective larvae. There were statistically significant differences (P < 0.05) between the antagonistic effects of three isolates of A. robusta, but there was no such difference between the isolate of A. conoides and isolates of A. robusta. This result indicates that there can be a variation in the predatory capacity of different isolates within a single fungus species. After 20 days of assay, there was greater recuperation of infective H. placei larvae in group 3 compared to group 1.

Animals↗
PubMed2003

Effect of mycoparasitic fungi on the development of Sphaerotheca fusca in melon leaves.

We evaluated the possibilities of exploitation of several mycoparasitic fungi in the biocontrol of cucurbit powdery mildew (Sphaerotheca fusca) in melon greenhouses. To simplify the screening, an in vitro biological control test on detached leaves of melon has been used and a detailed microscopic analysis of the interactions between mycoparasites and S. fusca conducted. In this context, the effect of mycoparasitic fungi on the formation of infection structures of S. fusca such as haustoria, conidia and conidiospores has been quantified. On the basis of the microscopic data, effect of mycoparasites on severity and incidence of cucurbit powdery mildew has been discussed. Our results show that, under controlled environmental conditions, Acremonium alternatum, Ampelomyces quisqualis and especially Lecanicillium lecanii, when applied in early stages of infection, were able to significantly reduce cucurbit powdery mildew symptoms and S. fusca development on melon leaves. These results indicate that these mycoparasites are promising candidates for the biocontrol of cucurbit powdery mildew in melon greenhouses.

Antibiosis↗
PubMed2004

Colonisation and molecular diversity of arbuscular mycorrhizal fungi in the aquatic plants Littorella uniflora and Lobelia dortmanna in southern Sweden.

The colonisation intensity and composition of the mycorrhizal community in the aquatic plants Lobelia dortmanna and Littorella uniflora were studied. The mycorrhizal fungi were characterised by fungal specific nested PCR and sequencing using the 5'-end of the LSU rDNA as target. For this, primers for the clade of Acaulospora, the clade including Glomus mosseae and G. intraradices and the clade containing G. etunicatum and G. claroideum were used. The nested PCR products were screened for different sequence types using single stranded conformation polymorphism (SSCP) and representatives for each type were sequenced. A phylogenetic analysis of the sequences showed two phylotypes of Acaulospora, one phylotype within the clade of G. etunicatum/G. claroideum and five within the G. mosseae/ G. intraradices clade. The colonisation intensity was comparable to that seen in typical grassland vegetation. The neutral lipid fatty acid 16: 1omega5 was seen to be indicative of mycorrhizal colonisation with concentrations up to 35 nmol mg(-1) root DW, which indicates that the fungi are active.

Fatty Acids↗
PubMed2004

Ionizing radiation attracts soil fungi.

During the last 15 years, about 2000 strains of 200 species of 98 genera of fungi have been isolated from around the Chernobyl Atomic Energy Station. Many of these microfungi are capable of growing into and decomposing 'hot particles'; carbon based radioactive graphite from the reactor and there are suggestions that some fungi actively direct their growth toward sources of radioactivity, possibly attracted to the carbon skeleton of these structures. In our experiments, we eliminated the confounding effects of carbon as a fungal resource, by developing experimental protocols that expose fungal spores and their germinating hyphae to directional sources of ionizing radiation allowing us to measure fungal response to ionizing radiation per se. We show that both beta and gamma radiation promote directional growth of hyphae towards the source of ionizing radiation.

Beta Particles↗