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 613 records · Page 34Linked to original sources
PubMed2006

Role of sooty mold fungi in accumulation of fine-particle-associated PAHs and metals on deciduous leaves.

The focus of this research was on elucidation of the role of deciduous tree ecosystems in accumulation of fine-particle-associated polycyclic aromatic hydrocarbons (PAHs) and heavy metals on leaves of deciduous trees. The studied species were Tilia x euchlora (frequently infested by sooty mold fungi) and Pyrus calleryana (unaffected by sooty mold fungi). The selected species have similar leaf morphology and were exposed to identical environmental conditions. Intra-species comparison showed that moldy linden leaves accumulate significantly higher amounts of PAHs and metals than unaffected linden leaves. Inter-species comparison revealed that in the absence of sooty mold fungi, physico-chemical properties of epicuticular waxes, rather than the amounts of waxes, might play an important role in accumulation of particulate matter on leaves. The accumulation and/or degradation of a number of high-molecular-weight (HMW) PAHs on leaves was temperature dependent. The results show that the presence of sooty mold fungi on deciduous leaves alters either the accumulation modes and/or degradation pathways of PAHs on deciduous leaves.

Air Pollutants↗
PubMed2005

Antiangiogenic activities of polysaccharides isolated from medicinal fungi.

Extracted polysaccharides from medicinal fungi, including Antrodia cinnamomea, Antrodia malicola, Antrodia xantha, Antrodiella liebmannii, Agaricus murrill, and Rigidoporus ulmarius, were investigated for their effects on vascular endothelial growth factor (VEGF)-induced tube formation in endothelial cells (ECs). Chemical analysis revealed that myo-inositol, sorbitol, fucose, galactosamine, glucosamine, galactose, glucose, and mannose were the neutral sugars in these polysaccharides. These fungal polysaccharides showed no toxicity to ECs. For the inhibition of endothelial tube formation, extracted polysaccharides from A. xantha and R. ulmarius were shown to produce greater inhibition compared to those from other fungi. Fucose, glucose and mannose were the predominant monosaccharides from these two fungi. These results suggest that monosaccharides may play a role in the inhibitory effect of these fungi on endothelial tube formation. In contrast to the inhibition on tube formation from polysaccharides of A. cinnamomea and A. malicola, polysaccharides from A. xantha and R. ulmarius, with molecular weight between 2693-2876 and 304-325 kDa, were critical for this inhibitory activity. Our results show that polysaccharides isolated from A. xantha and R. ulmarius provide greater antiangiogenesis than those from commercialized A. murrill (Brazilian mushroom) and A. cinnamomea. These studies provide a basis for the potential development of these polysaccharides for antiangiogenesis usage.

Angiogenesis Inhibitors↗
PubMed2004

Double-joint PCR: a PCR-based molecular tool for gene manipulations in filamentous fungi.

Gene replacement via homologous double crossover in filamentous fungi requires relatively long (preferentially >0.5 kb) flanking regions of the target gene. For this reason, gene replacement cassettes are usually constructed through multiple cloning steps. To facilitate gene function studies in filamentous fungi avoiding tedious cloning steps, we have developed a PCR-assisted DNA assembly procedure and applied it to delete genes in filamentous fungi. While the principle of this procedure is essentially the same as other recently reported PCR-based tools, our technique has been effectively used to delete 31 genes in three fungal species. Moreover, this PCR-based method was used to fuse more than 10 genes to a controllable promoter. In this report, a detailed protocol for this easy to follow procedure and examples of genes deleted or over-expressed are presented. In conjunction with the availability of genome sequences, the application of this technique should facilitate functional characterization of genes in filamentous fungi. To stream line the analysis of the transformants a relatively simple procedure for genomic DNA or total RNA isolation achieving approximately 100 samples/person/day is also presented.

Aspergillus nidulans↗
PubMed2005

DC-SIGN mediates the binding of Aspergillus fumigatus and keratinophylic fungi by human dendritic cells.

Human contact with fungi does not usually lead to pathological consequences, as the immune system manages to defeat the invader pathogens. Nevertheless, under immune suppression, fungi overcome immune defenses and cause diseases that range from nonserious colonizations of keratinizated tissue (Dermatophytosis) to life threatening disseminated infections (Aspergillosis). Host defenses against fungi rely on innate and adaptative responses, with dendritic cell (DC) and macrophage surface receptors having a major role in the recognition of fungal pathogens and in the orchestration of an effective immune response. DC-SIGN is a C-type lectin involved in the recognition of bacterial, viral and parasitic pathogens, as well as in interactions between cells of the immune system. Its expression is restricted to DCs and subsets of macrophages. Here we show that DC-SIGN mediates the binding and capture of Aspergillus fumigatus and keratinophylic fungi, including Chrysosporium tropicum, by human DCs, describe the requirements of these interactions and discuss their potential involvement in the onset and persistence of pulmonary fungal infections.

Animals↗
PubMed2004

Growth substrate selection and biodegradation of PCP by New Zealand white-rot fungi.

Nine New Zealand native white-rot fungi were studied for their ability to grow and survive on different substrates formulated from bark, wheat straw, sawdust, apple pomace and maize products in order to identify their pentachlorophenol (PCP) biodegradation potential and to select a fungal carrier for bioaugmentation of polluted soils. Isolates were also evaluated to mineralize (14)C-PCP in liquid culture and in soil. The American fungus Phanerochaete chrysosporium outgrew the native fungi on the substrates tested, but the high colonisation did not result in superior PCP dechlorination as measured by chloride release. Whilst Trametes versicolor inocula produced on wheat straw and SCS (sawdust-corn meal-starch-mix) gave the highest chloride release, colonization of these two substrates as measured by biological potential was lower compared to the pomace and pomace-sawdust-mix. Neither lignin peroxidase nor manganese peroxidase production were measured for New Zealand white-rot fungi during the experiments. Laccase was the only enzyme detected. In liquid culture, the mineralisation rate was higher for T. versicolor isolates compared to P. chyrysoporium. Very little to no pentachloroanisole (PCA) was captured in the volatile fraction of T. versicolor isolates, whereas 75% of the volatile fraction of P. chrysosporium consisted of PCA. The soil microcosms studies, using contaminated soil from a timber treatment site, clearly showed that the New Zealand T. versicolor isolates mineralized PCP. Degradation of PCP in non-sterile soil was higher in the presence of white-rot fungi than in soil without white-rot fungus. This demonstrates that viable white-rot fungus is necessary for significant PCP degradation and that T. versicolor isolates showed PCP remediation potential. Wheat straw and SCS could be suitable carriers for New Zealand native T. versicolor isolates for bioremediation of PCP polluted soil sites.

Biodegradation, Environmental↗
PubMed2006

Beneficial effect of saprobe and arbuscular mycorrhizal fungi on growth of Eucalyptus globulus co-cultured with Glycine max in soil contaminated with heavy metals.

The effects of saprobe and arbuscular mycorrhizal (AM) fungi on growth, chlorophyll and N, P and K content of Eucalyptus globulus Labill. growing in soil contaminated by heavy metals in the presence or absence of Glycine max were investigated. Glomus mosseae and Glomus deserticola increased dry weight, shoot length, total N, P and K concentration and the quantity of chlorophyll in E. globulus shoots. The protection of Eucalyptus by AM fungi against the action of the heavy metals was more evident when this plant grew as an intercrop with soybean than as a monoculture. The presence of the saprobe fungi Fusarium concolor and Trichoderma koningii further enhanced shoot dry weight, N, P and K content of AM Eucalyptus. The co-inoculation of Eucalyptus with Glomus deserticola and T. koningii was more effective for Cd uptake. In addition, Glomus deserticola enhanced the amount of Pb absorbed by Eucalyptus plants. We showed that it is important to select the most efficient AM and saprobe fungi to stimulate plant growth in heavy-metal-contaminated soil and that the combination of both plays an important role in metal tolerance of Eucalyptus plants.

Biological Availability↗
PubMed2006

The C-terminal TPR domain of Tom70 defines a family of mitochondrial protein import receptors found only in animals and fungi.

In fungi and animals the translocase in the outer mitochondrial membrane (TOM complex) consists of multiple components including the receptor subunit Tom70. Genome sequence analyses suggest no Tom70 receptor subunit exists in plants or protozoans, raising questions about its ancestry, function and the importance of its activity. Here we characterise the relationships within the Tom70 family of proteins. We find that in both fungi and animals, a conserved domain structure exists within the Tom70 family, with a transmembrane segment followed by 11 tetratricopeptide repeat motifs organised in three distinct domains. The C-terminal domain of Tom70 is highly conserved, and crucial for the import of hydrophobic substrate proteins, including those with and those without N-terminal presequences. Tom70 likely arose after fungi and animals diverged from other eukaryote lineages including plants, and subsequent gene duplication gave rise to a paralogue specific to the Saccharomyces group of yeasts. In animals and in fungi, Tom70 plays a fundamental role in the import of precursor proteins, by assisting relatively hydrophobic regions of substrate proteins into the translocation channel in the outer mitochondrial membrane. Proteins that function equivalently to Tom70 may have arisen independently in plants and protists.

Animals↗
PubMed2000

[Nosocomial infections due to opportunistic fungi: analysis of a news outbreak in the Spanish press].

BACKGROUND: To study an outbreak of media news related to nosocomial infections due to opportunistic fungi in Spanish hospitals. METHOD CASE DEFINITION: any news related to possible nosocomial infection due to opportunistic fungi in Spanish hospitals, published in national or local daily newspapers, over the pre-epidemic (July-December, 1998) and epidemic periods (January-June, 1999). All news were reviewed and identified using global press reports summaries, prepared by two independent sources, and were analyzed by three different observers. RESULTS: Over the pre-epidemic period there were not any news related to nosocomial infections due to opportunistic fungi. Over the epidemic period, a total of 218 news were identified, 154 (71%) published in national newspapers and 64 (29%) in local ones. We analyzed separately 18 editorials or opinion articles related to this subject. The epidemic curve (distribution of news by week) showed an incidence news peak at week 5 (102 news, 46.7% of all news published). The media mentioned up to 19 different hospitals as institutions with possible cases of nosocomial fungal infections. After week 8, news incidence drop, and remain thereafter at minimum levels. CONCLUSIONS: The example provided by the analysis of this outbreak of media news, related to nosocomial infections by Aspergillus an other opportunistic fungi, is useful to allow us understand how some medical news arise, develop and were transmitted. The public alert situation created in Spain was remarkable, and it is likely that there was a transient loss of confidence in the safety of public health institutions. Today's medicine requires a great and better openness to the media, and a better cooperation between both parts.

Cross Infection↗
PubMed2001

The utilization of aniline, chlorinated aniline, and aniline blue as the only source of nitrogen by fungi in water.

The ability of fungi to degrade aniline and its derivatives in water is reported. Several fungi are able to degrade aniline and its derivatives as a sole nitrogen, carbon and energy source. Some of these fungi were obtained from activated sludge by enrichment technique. Among the 10 studied fungi, Fusarium sp. and Rhizopus sp. utilize aniline as a sole nitrogen, carbon and energy source, with production of acetanilide and catechol. Fusarium sp. utilized 70% of 10 mmol aniline and produced 3.55 mM ammonia during 30 days. Rhizopus sp. utilized 65% of 10 mmol aniline during 30 days. Rhizopus sp. and Fusarium sp. utilized only 2-chloroaniline and 3-chloroaniline as nitrogen source in the presence of glucose, with production of catechol, ammonium and chloride. The utilization of 2-chloroaniline was better than 3-chloroaniline, by Fusarium sp. and Rhizopus sp. Cladosporium sp. was the best isolate which could use aniline blue as the only source of nitrogen. This fungus reduced 89% of aniline blue, and ammonia is produced as the result of aniline blue biodegradation by Cladosporium sp.

Alternaria↗
PubMed2002

Occurrence of xerophilic fungi in bakery gingerbread production.

The production process of a coconut type of gingerbread was examined for possible sources of contamination with xerophilic fungi. In the production flow chart, critical control points were found at which some effective steps could be made to eliminate undesirable fungal contamination, affected by water activity and temperature, and to prevent mould spoilage of the products. The following xerophilic fungi were detected, isolated and identified: Eurotium amstelodami, E. chevalieri, E. herbariorum, E. rubrum and Wallemia sebi. The resistance of these fungi against elevated temperature and preserving agents was investigated. It was found that Eurotium species were more resistant than W. sebi. Preservation against xerophilic fungi was more effective with the use of propionic acid than with potassium sorbate.

Ascomycota↗
PubMed1997

Flow sensing in mycelial fungi.

Hyphae of a variety of mycelial fungi were shown to reorient their direction of growth to grow upstream in a continuous flowing current of liquid medium. Among those tested fungi, Aspergillus niger hyphae was most polarized towards the upstream. Hyphae of A. niger which had been attached to poly-L-lysine coated plates on the base of a continuous-culture flow cell were exposed to a current of medium of flow rates in the range of 0-6400 microns s-1 for 1-4 h. Hyphal tips quickly reoriented towards the upstream of the flowing medium and became aligned parallel to the flow axis as they grew larger. At flow rates above 1600 microns s-1, however, the percentage of polarization of hyphae reached a constant level. With other fungi, germ tube emergence was not polarized but hyphae and branches grew towards the upstream. There was no detectable difference in the pH and oxygen concentration of the flowing medium between inlet and outlet of the flow cell. This result suggests that hyphae of mycelial fungi sense transient flow of liquid medium over their surface and reorient their direction to grow upstream.

Aspergillus niger↗
PubMed2002

Antigenic and allergenic cross-reactivity of Epicoccum nigrum with other fungi.

BACKGROUND: Previous studies have identified Epicoccum nigrum (EN) as an important aeroallergen. Shared allergenicity among some fungi responsible for type I allergic disorders has been reported. OBJECTIVE: To study the cross-reactivity among different fungi and to identify immunoglobulin (Ig)G and IgE binding components shared between EN and 10 other fungi known to cause respiratory allergy. METHODS: Cross-reactivity studies were carried out by enzyme-linked immunoadsorbent assay (ELISA) and immunoblot inhibition using both rabbit antiserum raised against EN and pooled sera from patients' EN-positive skin test. RESULTS: A large number (82%) of EN-sensitive patients showed positive skin reactivity to other fungal extracts. ELISA inhibition revealed >50% inhibition in binding of EN-specific rabbit antibodies with Alternaria alternata, Curvularia lunata, Cladosporium herbarum, and Penicillium citrinum extract, whereas the other extracts showed only 20 to 40% inhibition. Rabbit antisera to A. alternata, C. herbarum, and C. lunata reacted with five to seven bands in EN, demonstrating the presence of shared antigens among these fungi. EN requires an amount of 100 ng for 50% IgE ELISA inhibition, whereas 175 ng of A. alternata, 160 ng of C. lunata, and 268 ng of C. herbarum and P. citrinum were required for the same. IgE immunoblot and immunoblot inhibition further revealed that 43-, 26-, and 17-kD allergenic bands were shared by EN and A. alternata, whereas the 80- and 37-kD bands were common to both EN and C. lunata. EN and C. herbarum shared 63- and 36-kD allergenic bands, whereas EN and P. citrinum shared the 34-kD band. CONCLUSION: EN showed maximum cross-reactivity with A. alternata followed by C. lunata, C. herbarum, and P. citrinum. This information will be useful in treating EN-allergic patients.

Allergens↗
PubMed1999

Evaluation of IgE-sensitization to fungi in HIV-positive patients with eczematous skin reactions.

BACKGROUND: Human immunodeficiency virus infection is associated with declining immune function and polyclonal B-cell activation leading to elevated IgE-levels. In selected patient categories, increased total IgE may be associated with allergic diseases. Furthermore, a significant number of patients with low CD4+ cell numbers have various skin manifestations, eg, eczema and dermatophytosis. Patients with chronic fungal infections and a tendency to produce increased levels of specific IgE may become allergic and IgE-mediated mechanism may contribute to inflammatory reactions in the skin. OBJECTIVE: This study investigates IgE-sensitization of patients infected with human immunodeficiency virus to a panel of fungal extracts of Candida albicans, Fusarium moniliforme, Penicillium notatum, Pityrosporum ovale, and Trichophyton rubrum. METHODS: Fifteen HIV-positive patients with eczematous skin manifestations and five non-atopic healthy controls were evaluated by basophil histamine release and skin prick test with fungal extracts. The extracts were separated by sodium dodecylsulfate-polyacrylamide gel electrophoresis under reducing conditions and analyzed by IgE-immunoblotting with sera from the patients and controls. RESULTS: Thirteen of 15 patients (87%) released histamine to one or more of the fungi. Skin prick test was positive to one or more fungi in 7 (47%) patients. Patient sera revealed binding to a wide range of IgE-binding components present in the fungal extracts. The IgE response was most often directed against a 46-kD main protein in the Candida albicans extract. There was no correlation between total serum IgE, CD4+ cell counts, and frequency of IgE-sensitization to fungi. CONCLUSION: The human IgE response in HIV-infected patients appears to be polyspecific and may be directed against various fungi of which Candida albicans may be an important allergen. It is possible that the sensitization is due to frequent infections with Candida albicans in this patient population. No unspecific fungal reactions were noted among control patients. These results suggest that allergen-specific IgE-mediated mechanism may contribute to the pathogenesis of the eczematous skin reaction in HIV-infected patients.

Allergens↗
PubMed2002

Dissimilatory nitrate reduction metabolisms and their control in fungi.

Most fungi grow under aerobic conditions by generating ATP through oxygen respiration. However, they alternatively express two pathways of dissimilatory nitrate reduction in response to environmental oxygen tension when the oxygen supply is insufficient. The fungus Fusarium oxysporum expressed the pathway of respiratory nitrate denitrification that is catalyzed by the sequential reactions of nitrate reductase and nitrite reductase. These enzymes are coupled with ATP generation through the respiratory chain and produce nitric oxide. Fungal nitric oxide reductase uses NADH as the direct electron donor in contrast to bacterial systems and thus might function in regeneration of NAD+ and detoxification of the toxic radical, nitric oxide. Another pathway of nitrate dissimilation by fungi reduces nitrate to ammonium and couples acetogenic reaction with substrate-level phosphorylation. This metabolic mechanism is also in feature of a variety of fungi and it is called ammonia fermentation. Thus, fungi adapt to various aerated conditions using these pathways of nitrate dissimilation in addition to conventional oxygen respiration.

Journal Article↗
PubMed2005

Influence of different AM-fungi on the growth, nutrition and forskolin content of Coleus forskohlii.

A glasshouse investigation was conducted to study the effectiveness of 11 arbuscular mycorrhizal (AM) fungi on the medicinal plant Coleusforskohlii. Coleus plants raised in presence of most of the AM fungi in polythene bags showed an increase in plant growth (height, number of branches and biomass), P, and forskolin contents over those grown in the absence of soil inoculation with AM fungi. The extent of growth, P, and forskolin status varied with the AM fungi used. Based on the plant biomass, P uptake and forskolin content per plant, Glomus bagyarajii was found to be the best AM symbiont for inoculating C. forskohlii, the next being Scutellospora calospora.

Coleus↗
PubMed2006

Occurrence of ochratoxin A- and aflatoxin B1-producing fungi in Lebanese grapes and ochratoxin a content in musts and finished wines during 2004.

This paper reports the results of an extensive survey on the occurrence of filamentous fungi isolated from wine-grapes in Lebanon and to test their ability to produce ochratoxin A (OTA) and aflatoxin B1 (AFB1) on CYA culture medium, in order to assess their potential for producing these mycotoxins on grapes. From the 470 grapes samples taken during season 2004, 550 fungi strains were isolated with 490 belonging to Aspergillus spp. and 60 belonging to Penicillium spp. All these isolated fungi starins were tested for their ability to produce OTA and AFB1. Aspergillus carbonarius shows that it is the only species able to produce OTA with a production percentage reaching 100% and a maximum concentration of 52.8 microg/g of Czapek yeast extract agar (CYA). In its turn, Aspergillus flavus was considered as the only AFB1-producing species with production percentage of 45.3% and a maximum concentration reaching 40 microg/g CYA. A total of 47 handmade musts produced from the collected grapes were also analyzed in order to correlate the presence of OTA in must and the occurrence of filamentous fungi on grapes; 57.4% were contaminated with OTA at low level with concentrations ranging between 0.011 and 0.221 microg OTA L(-1). The analysis of these must samples was not performed with regard to AFB1. Seventy samples of finish red wine were also assayed for OTA content. The results showed that 42 of the tested samples (60%) were found to be positive for OTA with low levels (0.012-0.126 microg OTA L(-1)).

Aflatoxin B1↗
PubMed2001

Host plant effects on activity of the mitosporic fungi Beauveria bassiana and Paecilomyces fumosoroseus against two populations of Bemisia whiteflies (Homoptera: Aleyrodidae).

Laboratory bioassays were conducted to determine the effect of host plant on mycosis in two geographically distinct populations of early 2nd-instar nymphs of Bemisia argentifolii Bellows & Perring from the entomopathogenic fungi Beauveria bassiana (Balsamo) Vuillemin and Paecilomyces fumosoroseus (Wize) Brown & Smith. Mycosis in B. argentifolii nymphs varied according to the host plant on which the nymphs were reared but not according to the population. Both populations of whiteflies reared on cotton were consistently significantly less susceptible to infection by either fungus than when reared on melon. We hypothesized that the cotton plant produced a fungal inhibitor that may confer protection on whiteflies feeding (and possibly sequestering) upon it. Germination of conidia of both fungi was strongly inhibited (below 12% germination) on the cuticle of nymphs reared on cotton but was over 95% on the cuticle of nymphs reared on melon. We further hypothesized that the terpenoid gossypol, produced by many cultivars of cotton, might have been involved in antibiosis. Gossypol mixed with Noble agar at five concentrations was tested for its effects on germination of conidia of both fungi. P. fumosoroseus was highly tolerant of gossypol, even at the relatively high concentration of 1000 ppm, while B. bassiana tolerated gossypol at concentrations up to 500 ppm and strong inhibition only occurred in presence of gossypol at 1000 ppm. Our in vivo findings on cotton and on the insect's cuticle pointed at a potential host plant-mediated antibiosis. The in vitro tolerance of P. fumosoroseus and partial tolerance of B. bassiana to gossypol disagreed with our in vivo data. Gossypol concentrations higher than 1000 ppm might have increased the sensitivity of the fungi in our in vitro tests. Sequestered gossypol (and/or other cotton plant allelochemicals) by B. argentifolii nymphs would explain, at least partially, the insect's defense against the pathogens.

Animals↗
PubMed2002

Effects of some groundnut packaging methods and protection with Ocimum and syzygium powders on kernel infection by fungi.

Powders from the leaves of Ocimum gratissimum and cloves of Syzygium aromaticum were used as protectants at 3% (w/w) in combination with various packaging methods to store 3.5 kg groundnut kernel samples (9.3% moisture) artificially inoculated with Aspergillus parasiticus. Phostoxin-protected and unprotected samples were the controls. Packaging was accomplished with (i) Jute bags; JB (ii) Interlaced polypropylene bags; IPPB (iii) Polyethylene bags; PB (iv) PB inserted into IPPB and (v) PB inserted into JB. Selected treatments were repeated concurrently with naturally infected kernels (6.6% moisture). With 9.3% moisture kernels, there was a highly significant protectant, packaging method, and protectant X packaging method effect on protection of kernels from fungal infection at 2, 4, and 6 months. Packaging with JB and IPPB with or without plant powders gave 100% protection against fungi but insect infestation was prevented only when the Syzygium powder was used. When PB was used either singly or in combination with JB and IPPB, 100% protection from fungi was achieved up to 2 months with the Ocimum and up to 4 months with the Syzygium powder. The phostoxin treatment also gave 100% protection with JB and IPPB packaging but was ineffective with PB packaging. Kernels packaged with PB without the powders were extensively mouldy. Kernels with natural mycoflora (6.6% moisture) were free from fungi at 6 months regardless of the protectant and packaging used. In further tests, the Syzygium powder, at 3% and in combination with JB-packaging, effectively suppressed cross infection of healthy kernels (12% moisture) by fungi from diseased kernels when both kernel types occurred in the same lot. At 18.5% kernel moisture and with identical packaging, the Syzygium powder at 3%, was not as effective.

Aflatoxins↗