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PubMed2005

Biotic relation between Fusarium oxysporum schlecht. and fungi isolated from the substrate of Stewartia pseudocamellia (max.).

The effect of the fungi community colonizing the substrate of Stewartia plants on the growth of Fusarium oxysporum Schlecht. was investigated. The soil samples from 2 years old Stewartia cuttings were taken for analysis in the second decade of October 2002 and 2003, when the symptoms of disease appeared on Stewartia plant. Fungi were isolated from the substrate using the sand method (Mańka K. 1974). Fusarium oxysporum were isolated from root system of Stewartia pseudocamellia plant. The isolates selected for the investigation proved pathogenic influence on Stewartia in an infection experiment. For estimation of biotic effect of saprobiotic fungi community on Stewartia pathogen F. oxysporum the biotic series method (Mańka K. 1974) was applied. The results showed that species of genera: Penicillium and Trichoderma were the most frequent in the community of fungi in the substrate. Both fungi communities of these fungi could not limit the growth of investigated pathogen F. oxysporum. It showed negative ABSTRACT biotic effect. The strongest antagonistic effect displayed Trichoderma viride and Trichoderma harzianum.

Fusarium↗
PubMed1982

[The role of clothing in the transmission of pathogenic fungi ].

Laboratory studies were made to examine the possibility of transmission of pathogenic fungi through textiles. 1. Dermatophytes were proven to be present in clothing and leather articles worn over areas infected by fungi. In patients known to be infected with Pityriasis versicolor, contaminated scales were obtained from their textiles, the fungi could be demonstrated. 2. Artificially infected textiles were found to harbor dermatophytes and pathogenic yeasts for a number of weeks without limiting the survival capacity of the fungi. 3. At low temperatures, fungi were not affected by various detergents. Under conditions simulating machine washings (30 minutes exposure time) at a temperature of 60 degrees C any washing agent was sufficient to cause irreversible damage. At higher temperatures the time for killing the fungi was diminished. These results were confirmed by experiments with contaminated material from patients (scales, hairs, nail particles).

Arthrodermataceae↗
PubMed1968

The metabolism of aromatic acids by micro-organisms. Metabolic pathways in the fungi.

1. The metabolic pathways of aromatic-ring fission were examined in a range of fungal genera that utilize several compounds related to lignin. 2. Most of the genera, after growth on p-hydroxybenzoate, protocatechuate or compounds that are degraded to the latter (e.g. caffeate, ferulate or vanillate), rapidly oxidized these compounds, but not catechol. 3. Such genera possessed a protocatechuate 3,4-oxygenase and accumulated beta-carboxymuconate as the product of protocatechuate oxidation. This enzyme had a high pH optimum in most organisms; the Rhodotorula enzyme was competitively inhibited by catechol. 4. beta-Carboxymuconate was converted by all competent fungi into beta-carboxymuconolactone, which was isolated and characterized. None of the fungi produced or utilized at significant rates the corresponding bacterial intermediate gamma-carboxymuconolactone. 5. The lactonizing enzymes of Rhodotorula and Neurospora crassa had a pH optimum near 5.5 and approximate molecular weights of 19000 and 190000 respectively. 6. The fungi did not degrade the isomeric (+)-muconolactone, gamma-carboxymethylenebutanolide or beta-oxoadipate enol lactone at significant rates, and thus differ radically from bacteria, where beta-oxoadipate enol lactone is the precursor of beta-oxoadipate in all strains examined. 7. The end product of beta-carboxymuconolactone metabolism by extracts was beta-oxoadipate. 8. Evidence for a coenzyme A derivative of beta-oxoadipate was found during further metabolism of this keto acid. 9. A few anomalous fungi, after growth on p-hydroxybenzoate, had no protocatechuate 3,4-oxygenase, but possessed all the enzymes of the catechol pathway. Catechol was detected in the growth medium in one instance. 10. A strain of Penicillium sp. formed pyruvate but no beta-oxoadipate from protocatechuate, suggesting the existence also of a ;meta' type of ring cleavage among fungi.

Ascomycota↗
PubMed1982

Isolation of fungi from bats of the Amazon basin.

A total of 2,886 bats captured in the Amazon Basin of Brazil were processed for the isolation of fungi. From the livers, spleens, and lungs of 155 bats (5.4%), 186 fungal isolates of the genera Candida (123 isolates), Trichosporon (26 isolates), Torulopsis (25 isolates), Kluyveromyces (11 isolates), and Geotrichum (1 isolate) were recovered. Seven known pathogenic species were present: Candida parapsilosis, C. guilliermondii, C. albicans, C. stellatoidea, C. pseudotropicalis, Trichosporon beigelii, and Torulopsis glabrata. Twenty-three culture-positive bats showed identical fungal colonization in multiple organs or mixed colonization in a single organ. The fungal isolation rates for individual bat species varied from 1 fungus per 87 bats to 3 fungi per 13 bats, and the mycoflora diversity for members of an individual fungus-bearing bat species varied from 16 fungi per 40 bats to 7 fungi per 6 bats. Of the 38 fungal species isolated, 36 had not been previously described as in vivo bat isolates. Of the 27 culture-positive bat species, 21 had not been previously described as mammalian hosts for medically or nonmedically important fungi.

Animals↗
PubMed1963

Psychrophilic and mesophilic fungi in frozen food products.

The mold flora of certain frozen pastries and chicken pies was investigated. Molds were determined qualitatively or quantitatively, or both, by preparing pour plates of the blended product and incubating the plates at various temperatures. The mesophilic fungal flora developed on plates incubated at 10 and 20 C, whereas psychrophilic fungi were obtained on plates incubated at 0 and 5 C. About 2,000 cultures of fungi, representing about 100 different species, were isolated from various products. Four different brands of blueberry, two brands of cherry pastries, two brands of apple, and one brand of raspberry pastries were examined. In addition, two brands of chicken pies were studied. Blueberry pastries had a much higher total fungal population than the other products, although different brands of blueberry pastries varied considerably. Blueberry pastries had from 347 to 1,586 psychrophilic fungi per g. Cherry pastries had about 70 to 110 psychrophiles per g, and apple pastries had 19 to 92 psychrophiles per g. Chicken pies contained very few psychrophilic fungi, about 15 per g. Aureobasidium pullulans was recovered most frequently. About 90% of the psychrophilic fungi found in blueberry products was A. pullulans. Depending upon the brand of cherry pastry, either Phoma spp. or A. pullulans was the most common fungus present. Apple pastries also displayed brand variation, but were unique in having many mesophilic aspergilli. This genus was generally absent from other products. The Penicillium content of apple pastries was also rather high; 50% of the psychrophilic flora was represented by this genus. The psychrophilic fungal flora of chicken pies was composed primarily of penicillia (50%) and Chrysosporium pannorum (46%).

Aspergillus↗
PubMed1972

Fungi isolated from flue-cured tobacco sold in Southeast United States, 1968-1970.

Flue-cured tobacco leaves, from low- and middle-stalk positions, offered for sale in each of two markets, within each of five tobacco types, were evaluated for moisture content (MC) and filamentous fungi during August through October in 1968, 1969, and 1970. Alternaria alternata, Penicillium cyclopium, Aspergillus niger, Aspergillus repens, and Aspergillus flavus were most frequently isolated from cultured tissue. Other filamentous fungi that grew from the tissue included species from four genera of field fungi and seven species of storage fungi. Although the MC ranged from 11.0 to 22.5%, it averaged 16.4, 16.8, and 15.9% for samples taken in 1968, 1969, and 1970, respectively. Average populations of fungi per sample over the three years ranged from 0 to 1,528,500 colonies/g of tobacco.

Aspergillus↗
PubMed1977

Growth of fungi in broiler houses.

The growth of fungi in broiler houses with and without histories of problems of unknown etiology or of mycotoxicoses was studied. Fungal growth data were obtained by the strip bait method and results expressed as frequency and relative density. The frequency and relative density of fungal growth of several species were higher in problem houses than in those without problems. In problem houses many known toxic fungi and several fungi of unknown toxicity were found growing, increasing in density and frequency during the rearing period. Houses without problems (control houses) were dominated throughout the rearing period by the growth of Scopulariopsis brevicaulis. This fungus grew infrequently and in low relative density in problem houses. There was no correlation between species composition and litter removal, pH, and moisture in problem and control houses. Fungi did not grow in inside feed hoppers or in dust on rafters in the broiler houses. One thermotolerant and two thermophilic species of fungi were found growing in outside feed bins. Three generalized fungal growth patterns in litter are described and theoretical consideration of environmental factors on these patterns are discussed.

Animals↗
PubMed1993

Metabolism of PAH by fungi and correlation with extracellular enzymatic activities.

The activity to metabolize the polycyclic aromatic hydrocarbons (PAH) phenanthrene, anthracene, pyrene, fluorene and fluoranthene by Trametes versicolor, Pleurotus ostreatus (white rot fungi), Laetiporus sulphureus, Daedaela quercina, Flamulina velutipes (brown rot fungi), Marasmiellus sp. (litter decaying fungus) and Penicillium sp. M 1 (isolated from a PAH contaminated soil sample) were compared. Screening methods for the presence of exoenzymes (peroxidases, polyphenoloxidases, "radical generating" enzymes) were evaluated for their use in screenings for fungi degrading PAH. Laetiporus sulphureus and Penicillium sp. M 1 cometabolize several PAH with rates comparable to white rot fungi. In most of the cases the patterns of extracellular peroxidases indicate the potential of fungi to degrade PAH.

Fungi↗
PubMedDate not supplied

HAP-Like CCAAT-binding complexes in filamentous fungi: implications for biotechnology.

Regulatory CCAAT boxes are found frequently in eukaryotic promoter regions. They are bound by different CCAAT-binding factors. Until now, a single CCAAT-binding complex has been reported in fungi. It is also found in higher eukaryotes and is highly conserved among eukaryotic organisms. This multimeric protein complex is designated HAP, AnCF, CBF, or NF-Y. The complex consists of at least three subunits. In fungi, only the HAP complex of Saccharomyces cerevisiae had been known for a long time. The recent cloning of genes encoding the components of the corresponding complex (AnCF/PENR1) of Aspergillus nidulans and characterization of CCAAT-regulated genes in A. nidulans, as well as other filamentous fungi, led to a deeper insight into the role of this transcription complex, in particular in aerobically growing fungi. An overview of the function of HAP-like complexes in gene regulation in filamentous fungi is presented. Some of the genes that have been found to be regulated by HAP-like complexes encode enzymes of biotechnological interest, like taka-amylase, xylanases, cellobiohydrolase, and penicillin biosynthesis enzymes. The importance of HAP-like complexes in controlling the expression of biotechnologically important genes is discussed.

Biotechnology↗
PubMed2000

Translocation induced outgrowth of fungi in nutrient-free environments.

The study of alternatives to chemical methods of nematode control in agriculture has received significant recent interest. One such method is biological control using nematode trapping fungi such as Arthrobotrys superba. To understand how these fungi can be implemented as effective nematicides, it is essential to study their outgrowth into soil from localized nutrient resources. In this paper, we use a mathematical model to investigate the outgrowth of fungi into an environment essentially without available nutrients capable of supporting net growth. By comparing model solutions with experimental results, we show that in such circumstances, continual mycelial expansion can only be obtained if internal metabolites are actively translocated through the mycelium. Predictions are made concerning the maximal extension possible from a given quantity of nutrients and a testable functional relationship between the two is derived. Using this modelling technique we are able to map not only biomass extent but also biomass distribution at each stage. The type of environmental heterogeneity investigated here is encountered by many species of fungi in nature and is of relevance for the introduction of specific fungi into soil for biological control or bioremediation purposes.

Animals↗
PubMed1992

Drug resistance in human pathogenic fungi.

Since the therapy of the mycoses, particularly the systemic mycoses, is relatively long-term in nature, emergence of resistance to antifungal drugs during the treatment of period would be of considerable clinical importance. However, most reports of resistance to antifungal agents among human pathogenic fungi indicate that naturally-occurring resistance is very rare, and that the induction of resistant mutants or variants is much more difficult to achieve in vitro and in vivo than with bacteria. As a matter of fact, amphotericin B and some other classic antifungals have not as yet posed a broadly significant problem relative to drug resistance despite their widespread and frequent use. Fungal resistance has thus received little attention, in contrast to the critical importance of bacterial resistance frequently caused by a variety of antibacterial chemotherapeutic agents, until a single exception to this generalization arose with the advent of flucytosine. This new development has aroused great interest in the problem of fungal resistance among the scientists involved with medical mycology. It is generally believed that fungi, like bacteria, are intrinsically capable of developing resistance to antifungal agents. As illustrated by flucytosine, inherently resistant mutants to antifungals occur within sensitive strains of human pathogenic fungi with significant frequency. Given the relatively high degree of such primary resistance, these mutants should develop secondary resistance during therapy, thus resulting in considerable limitations in the clinical usefulness of the antifungals. Virtually, all unsuccessful cases of mycoses treated with some of the recently exploited antifungal drugs, albeit scarce to date, would obviously be attributable to the occurrence of secondary resistance. The exploitation of new antifungal drugs thus requires investigations of their resistance as one of the most important research projects to be undertaken before receiving approval for use on humans. This paper reviews from various aspects the literature on resistance to various classic and novel antifungal agents among human pathogenic fungi. The resistance of some nonpathogenic fungi to these agents will also be described from genetic and biochemical points of view.

Antifungal Agents↗
PubMed1978

Role of opportunistic fungi in ocular infections in Nigeria.

The importance of opportunistic fungal pathogens in causing ocular infections is emphasized. A study was conducted over a period of 4 years (1974--1977) to investigate the role of opportunistic fungi in causing mycotic keratitis and to elucidate certain aspects of epidemiology of this disease in Nigeria. Fifty-nine cases of corneal ulcers of suspected mycotic etiology were investigated. Fungal etiology was confirmed in 42 of these cases. The predominant etiological agent was Fusarium solani in 14 cases (33.33%) followed by Penicillium citrinum in 8 cases (19.04%) and Aspergillus fumigatus in 5 cases (11.90%). The yeasts were responsible for only 3 cases (7.14%) i.e. one each caused by Candida albicans, C. parapsilosis and C. guilliermondii. Among the remaining 12 cases, one was caused by F. moniliforme, 3 by A. flavus, 2 each by A. niger, Penicillium expansum and Penicillium sp., and one each by Cladosporium cladosporioides and Cladosporium sp. The clinical features of the cases are briefly described. The incidence of mycotic keratitis in relation to sex, age, occupation, trauma and other factors has been analysed. Corneal trauma appeared to be an important predisposing factor as 27 (67.28%) of the patients gave a history of injuries to the eye. Notably, a large number of patients were farmers and trauma was most often from palm tree leaf, thorn, kernel or other plant objects. Topical application of corticosteroids or broad spectrum antibiotics did not seem to play an important role in the etiology of keratomycosis. Cases were recorded throughout the year although the number of cases was higher in the months of March--May, and November--December than that during the rest of the year. The isolates of the causative agents were studied in detail for their morphological and cultural characters. The isolates of F. solani grew well at 37 degrees C and survived at 40 degrees C for more than 3 weeks. In vitro drug sensitivity tests indicated good antifungal activity of pimaricin and econazole for F. solani, clotrimazole and econazole for Aspergillus fumigatus. A. flavus and Penicillium citrinum, and 5-fluorocytosine for Candida spp. Investigations on the incidence of fungi in normal healthy eyes of 450 persons comprising 204 adults and 246 children yielded 204 isolates belonging to 21 genera of fungi. Cladosporium was most frequent (12.88%) followed by Penicillium (10.22%) and Aspergillus (6.66%). Another important fungus was Fusarium represented by 10 isolates, viz. 4 of F. solani, 2 of F. moniliforme, 1 of F. exysporum, and 3 of Fusarium sp. The yeasts were represented by two isolates each of Candida tropicalis, C. pseudotropicalis, C. krusei, Trichosporon sp and Cryptococcus albidus, and one of Candida guilliermondii. Successive culturing of fungi from normal eyes in a small group indicated that fungi occur in the outer eye generally as transients. The epidemiology of mycotic keratitis has been discussed in relation to the present findings and in comparison with observations of other investigators.

Adolescent↗
PubMed1991

Occurrence of keratinophilic fungi on Indian birds.

Keratinophilic fungi were isolated from feathers of most common Indian birds, viz. domestic chicken (Gallus domesticus), domestic pigeon (Columba livia), house sparrow (Passer domesticus), house crow (Corvus splendens), duck (Anas sp.), rose-ringed parakeet (Psittacula krameri). Out of 87 birds, 58 yielded 4 keratinophilic fungal genera representing 13 fungal species and one sterile mycelium. The isolated fungi were cultured on Sabouraud's dextrose agar at 28 +/- 2 degrees C. Chrysosporium species were isolated on most of the birds. Chrysosporium lucknowense and Chrysosporium tropicum were the most common fungal species associated with these Indian birds. Maximum occurrence of fungi (47%) was recorded on domestic chickens and the least number of keratinophilic fungi was isolated from the domestic pigeon and duck. The average number of fungi per bird was found to be the 0.44.

Animals↗
PubMed2003

Recently discovered functions of glucosylceramides in plants and fungi.

Glycosphingolipids are ubiquitous membrane lipids of eukaryotic organisms and a few bacteria. Whereas inositol-containing glycosphingolipids are restricted to plants and fungi, galactosylceramide occurs only in fungi and animals. In contrast, glucosylceramide is the unique glycosphingolipid which plants, fungi and animals have in common. However, there are specific differences in the structure of the ceramide backbone of glucosylceramides from these organisms. A comparison of the structural features and the biosynthesis of glucosylceramides from plants, fungi and animals will contribute to our understanding of their functions, which so far have been analysed mainly in animals. The availability of nearly all genes involved in the biosynthesis of glucosylceramides enables the specific manipulation of glycosphingolipid metabolism by techniques of forward and reverse genetics. Application of this approach to unicellular organisms like yeasts, multicellular filamentous fungi, as well as to complex organisms like plants will reveal common and different glucosylceramide functions in these organisms. These glycolipids play a role both in intracellular processes and in cell-to-cell interactions. These interactions may occur between cells of a multicellular organism or between cells of different species, as in host-pathogen interactions.

Animals↗
PubMed2003

Interactions between Trichoderma pseudokoningii strains and the arbuscular mycorrhizal fungi Glomus mosseae and Gigaspora rosea.

The interaction between Trichoderma pseudokoningii (Rifai) 511, 2212, 741A, 741B and 453 and the arbuscular mycorrhizal fungi Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe BEG12 and Gigaspora rosea Nicolson & Schenck BEG9 were studied in vitro and in greenhouse experiments. All T. pseudokoningii strains inhibited the germination of G. mosseae and Gi. rosea except the strain 453, which did not affect the germination of Gi. rosea. Soluble exudates and volatile substances produced by all T. pseudokoningii strains inhibited the spore germination of G. mosseae. The germination of Gi. rosea spores was inhibited by the soluble exudates produced by T. pseudokoningii 2212 and 511, whereas T. pseudokoningii 714A and 714B inhibited the germination of Gi. rosea spores by the production of volatile substances. The strains of T. pseudokoningii did not affect dry matter and percentage of root length colonization of soybean inoculated with G. mosseae, except T. pseudokoningii 2212, which inhibited both parameters. However, all T. pseudokoningii strains decreased the shoot dry matter and the percentage of AM root length colonization of soybean inoculated with Gi. rosea. The saprotrophic fungi tested seem to affect AM colonization of root by effects on the presymbiotic phase of the AM fungi. No influence of AM fungi on the number of CFUs of T. pseudokoningii was found. The effect of saprotrophic fungi on AM fungal development and function varied with the strain of the saprotrophic species tested.

Fungi↗
PubMed2003

Diversity of arbuscular mycorrhizal fungi colonising roots of the grass species Agrostis capillaris and Lolium perenne in a field experiment.

Analysis of arbuscular mycorrhizal (AM) fungal diversity through morphological characters of spores and intraradicular hyphae has suggested previously that preferential associations occur between plants and AM fungi. A field experiment was established to investigate whether AM fungal diversity is affected by different host plants in upland grasslands. Indigenous vegetation from plots in an unimproved pasture was replaced with monocultures of either Agrostis capillaris or Lolium perenne. Modification of the diversity of AM fungi in these plots was evaluated by analysis of partial sequences in the large subunit (LSU) ribosomal RNA (rDNA) genes. General primers for AM fungi were designed for the PCR amplification of partial sequences using DNA extracted from root tissues of A. capillaris and L. perenne. PCR products were used to construct LSU rDNA libraries. Sequencing of randomly selected clones indicated that plant roots were colonised by AM fungi belonging to the genera Glomus, Acaulospora and Scutellospora. There was a difference in the diversity of AM fungi colonising roots of A. capillaris and L. perenne that was confirmed by PCR using primers specific for each sequence group. These molecular data suggest the existence of a selection pressure of plants on AM fungal communities.

Agrostis↗
PubMed1996

Inhibition of chitinolytic activities from tree species and associated fungi.

Effects of two inhibitors, allosamidin and (2-acetamido-2-deoxy-D-glucopyranosylidene)amino phenylcarbamate (PUGNAC), have been assessed on chitinolytic activities of two plants, Pinus sylvestris L. and Eucalyptus pilularis Sm., and of seven fungi. Pinus sylvestris and E. pilularis root endochitinase activities were inhibited by allosamidin. Activities of P. sylvestris were more sensitive to inhibition than those of E. pilularis. The mechanism of inhibition varied with the plant species and the enzyme involved. PUGNAC inhibited beta-N-acetylglucosaminidase and exochitinase activities in root extracts from both plant species. In all cases PUGNAC acted as a reversible competitive inhibitor. Both inhibitors also affected chitinolytic activities from the fungi screened. Allosamidin inhibited endochitinase activities from both the mycorrhizal and pathogenic fungi tested. In addition, exochitinase activity from the ectomycorrhizal fungus Paxillus involutus (Batsch) Fr. was inhibited by allosamidin. PUGNAC inhibited beta-N-acetylglucosaminidase activity from all the fungi tested. PUGNAC was also a potent inhibitor of both exo- and endochitinase activities from the fungi, except P. involutus. Competitive inhibition was the most common form. These findings show allosamidin does inhibit endochitinase activity in plants and the ability of PUGNAC to inhibit not only beta-N-acetylglucosaminidase activity but also fungal endochitinase activity may be useful to distinguish between host and fungal endochitinase activities in symbiotic or pathogenic dual systems.

Acetylglucosamine↗
PubMed1988

The relationship of insects to the deterioration of stored grain by fungi.

The data presented tests the hypothesis that knowledge of basic biological relationships between insects and fungi in the stored grain ecosystem can open new paths for management of the system. Evidence indicates: (1) some storage insect species are disseminators of storage fungi and some are exterminators; (2) some storage fungi attract storage insects and promote their population increases and other repel and secrete toxins harmful to insects; (3) certain morphophysiologic, biochemical similarities of fungi and the early developmental stages of insects suggest that new protective chemicals, 'insecticidal fungicides', could be designed or specifically sought. A specific example of a naturally occurring compound with dual action, sorbic acid (2,4-hexadienoic acid), is given and its effect on both insects and fungi is discussed. Sorbic acid is the only compound in the U.S. presently labelled by the FDA (Food and Drug Administration) as GRAS (Generally Regarded as Safe) and registered by the EPA (Environmental Protection Agency) for use on grain (maize) in storage.

Animals↗