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PubMed2006

Soil salinity delays germination and limits growth of hyphae from propagules of arbuscular mycorrhizal fungi.

Colonisation of plant roots by some arbuscular mycorrhizal (AM) fungi is reduced in the presence of sodium chloride (NaCl), probably due to a direct effect of NaCl on the fungi. However, there appear to be differences between the fungi in their ability to colonise plants in the presence of NaCl. This experiment tested the hypothesis that propagules of different isolates and species of AM fungi from saline and nonsaline soils would differ in their ability to germinate and grow in the presence of NaCl in the soil solution. Spores or pieces of root colonised by a range of AM fungi were incubated between filters buried in soil to which NaCl had been added at concentrations of 0, 150 or 300 mM in the soil solution. At regular intervals, filters were removed from the soil and both the percentage of propagules which had germinated and the length of proliferating hyphae were determined. Germination of spores of AM fungi studied was delayed in the presence of NaCl, but the fungi differed in the extent to which germination was inhibited. Two isolates of Scutellospora calospora reached maximum germination in 300 mM NaCl, but neither of two isolates of Acaulospora laevis germinated in the presence of NaCl. Germination of spores of the other fungi, including some isolated from saline soil, fell between these extremes. For some fungi, the specific rate of hyphal extension was reduced by NaCl. For others, the specific rate of growth was similar in the presence of NaCl to that in the control treatment, but overall production of hyphae was reduced in the NaCl treatments because germination was reduced.

Germination↗
PubMed2006

NADP-dependent glutamate dehydrogenase: a dispensable function in ectomycorrhizal fungi.

There is much controversy on the contribution of NADP-dependent glutamate dehydrogenase (NADP-GDH) in NH4+ assimilation in ectomycorrhizal (ECM) fungi and ectomycorrhizas. Experiments reported here provide information on the dispensability of NADP-GDH in various ectomycorrhizal isolates. Glutamate dehydrogenase and glutamine synthetase (GS) enzyme activities were measured on mycelia grown under various nitrogen (N) conditions. The contribution of GDH in ammonium assimilation was further estimated by following 15N incorporation from (15NH4)2SO4 into glutamate, when GS was inhibited by phosphinothricin. Finally, gene amplification on cDNA and genomic DNA was performed using degenerated primers. Two groups of fungi could be distinguished. The GDH+ fungi include Hebeloma cylindrosporum-like fungi, which possess a functional NADP-GDH. The GDH- fungi include Paxillus involutus-like fungi for which the NADP-GDH activity, as well as the GDHA transcripts, were not detected, whatever the growth condition. All the results are consistent with the dispensability of the NADP-GDH function in ECM fungi, suggesting a minor role in ammonium assimilation in ectomycorrhizal fungi. We hypothesize that the lack of a functional NADP-GDH could be an evolutive adaptation in relation to the ecological niche of ECM fungi, rather than a transitional regulation in response to changes in N contents of the extracellular medium.

Adaptation, Physiological↗
PubMed1995

Production of reactive oxygen metabolites by opsonized fungi and bacteria isolated from indoor air, and their interactions with soluble stimuli, fMLP or PMA.

Changes in the levels of free intracellular calcium ([Ca2+]i) and the production of reactive oxygen metabolites (ROM) induced by opsonized indoor air fungi and bacteria in human polymorphonuclear leukocytes (PMNL) were measured. Moreover, modification of a chemotactic peptide (fMLP)-and a tumor promoter (PMA)-induced production of ROM by opsonized fungi and bacteria were studied. The cells were exposed to graded doses of opsonized Candida sp., Aspergillus sp., Cladosporium sp., Stachybotrys sp., Penicillium sp., Paecilomyces sp., or A4 or A91 Streptomyces sp. alone, or together with fMLP or PMA. All the organisms were isolated from air samples of mold-problem buildings. None of the fungi or bacteria induced changes in [Ca2+]i or the production of ROM without opsonization with human serum. Of all opsonized fungi and bacteria, only Candida sp. elevated [Ca2+]i. All fungi and bacteria, except Paecilomyces sp. and Stachybotrys sp., markedly increased the production of ROM in PMNL. Furthermore, A91 Streptomyces sp. and Aspergillus sp. amplified fMLP-induced production of ROM. Only Candida sp. increased PMA-induced phenomen that normally occurs in the lung, was required for biological activity of the fungi and bacteria. Amplification by opsonization of fungi- or bacteria-induced leukocyte activation revealed remarkable changes between these biologically active particles. The present results suggest that many indoor air fungi and bacteria may activate leukocytes to produce oxidative stress, perhaps associated with harmful effects in exposed individuals.

Adult↗
PubMed1996

Human pathogeneic fungi and their close nonpathogenic relatives.

In order to understand the relationships between human pathogenic fungi and their close, nonpathogenic relatives, we compared small-subunit ribosomal DNA sequences among four closely related pathogens, Histoplasma capsulatum, Blastomyces dermatitidis, Trichophyton rubrum, and Coccidioides immitis, and seven nonpathogenic fungi expected on morphological grounds to be their nearest relatives. We sequenced small-subunit RNA genes from these fungi and used both genetic distance and parsimony algorithms to evaluate their evolutionary relationships to the pathogens. We show that the pathogens are not a monophyletic group, but rather are interspersed among nonpathogenic fungi; thus it is likely that pathogenicity has arisen multiple times within this group. The saprobic fungi Chrysosporium parvum and Uncinocarpus reesii are the closest known relatives of the highly pathogenic Blastomyces dermatitidis and Coccidioides immitis, respectively, and thus may be considered primary candidates for model systems for researchers studying these fungi. The branching order suggests that the conidium (asexual spore) types aleurioconidia and arthroconidia do not define monophyletic groups and may be less distinct than their names suggest. Fungi with a complete life cycle are shown to have closest relatives that lack a known sexual cycle. Such analyses offer a means by which the sexual and asexual fungi could be integrated into a single classification system.

Base Sequence↗
PubMed2005

Effects of tree phytochemistry on the interactions among endophloedic fungi associated with the southern pine beetle.

We examined the interaction between host trees and fungi associated with a tree-killing bark beetle, Dendroctonus frontalis. We evaluated (1) the response of four Pinus species to fungal invasion and (2) the effects of plant secondary metabolites on primary growth of and secondary colonization of three consistent fungal associates. Two of these fungi, Entomocorticium sp. A and Ophiostoma ranaculosum, are obligate mutualists with D. frontalis, and the third associate is a blue-staining fungus, O. minus, that is commonly introduced by beetles and phoretic mites. O. minus negatively affects beetle larvae and in high abundance can impact D. frontalis population dynamics. Size of lesions formed and quantity of secondary metabolites produced in response to fungal inoculations varied significantly among Pinus species. However, monoterpene composition within infected tissue did not significantly vary across treatments. While all eight tested metabolites negatively affected the growth rate of O. minus, only 4-allylanisole, p-cymene, and terpinene reduced the growth of the mycangial fungi. Surprisingly, growth rates of mycangial fungi increased in the presence of several secondary metabolite volatiles. O. minus out-competed both mycangial fungi, but the presence of secondary metabolites altered the outcome slightly. O. ranaculosum out-performed E. sp. A in the presence of dominant conifer monoterpenes, such as alpha- and beta-pinene. Volatiles from the mycangial fungi, particularly E. sp. A, had a negative effect on O. minus growth. In general, phloem phytochemistry of particular Pinus species appeared to alter the relative growth and competitiveness of mutualistic and non-mutualistic fungi associated with D. frontalis. The outcome of interactions among these fungi likely has important consequences for the population dynamics of D. frontalis.

Animals↗
PubMed2004

Living in a fungal world: impact of fungi on soil bacterial niche development.

The colonization of land by plants appears to have coincided with the appearance of mycorrhiza-like fungi. Over evolutionary time, fungi have maintained their prominent role in the formation of mycorrhizal associations. In addition, however, they have been able to occupy other terrestrial niches of which the decomposition of recalcitrant organic matter is perhaps the most remarkable. This implies that, in contrast to that of aquatic organic matter decomposition, bacteria have not been able to monopolize decomposition processes in terrestrial ecosystems. The emergence of fungi in terrestrial ecosystems must have had a strong impact on the evolution of terrestrial bacteria. On the one hand, potential decomposition niches, e.g. lignin degradation, have been lost for bacteria, whereas on the other hand the presence of fungi has itself created new bacterial niches. Confrontation between bacteria and fungi is ongoing, and from studying contemporary interactions, we can learn about the impact that fungi presently have, and have had in the past, on the ecology and evolution of terrestrial bacteria. In the first part of this review, the focus is on niche differentiation between soil bacteria and fungi involved in the decomposition of plant-derived organic matter. Bacteria and fungi are seen to compete for simple plant-derived substrates and have developed antagonistic strategies. For more recalcitrant organic substrates, e.g. cellulose and lignin, both competitive and mutualistic strategies appear to have evolved. In the second part of the review, bacterial niches with respect to the utilization of fungal-derived substrates are considered. Here, several lines of development can be recognized, ranging from mutualistic exudate-consuming bacteria that are associated with fungal surfaces to endosymbiotic and mycophagous bacteria. In some cases, there are indications of fungal specific selection in fungus-associated bacteria, and possible mechanisms for such selection are discussed.

Bacteria↗
PubMed2002

Occurrence and densities of fungi from northern Greek coastal bathing waters and their relation with faecal pollution indicators.

The objective of this study was to determine the frequency and densities of yeasts and filamentous fungi in coastal water samples as well as their correlation with the indicator bacteria of faecal pollution. The prevalence of fungi was investigated in parallel with the standard pollution indicator microorganisms in 197 marine water samples from six northern Greek prefectures during the bathing season May-October 1999. Filamentous fungi were isolated from all the examined samples and yeasts from 29 (14.7%) of them; among the positive samples, their mean counts were 90.9 and 38.4cfu/100 ml, respectively. A total of 23 genera of filamentous fungi and four genera of yeasts were identified. Prevailing genera of filamentous fungi were Penicillium, Aspergillus and Alternaria spp., whereas Candida spp. was the most frequently isolated yeast. Counts of yeasts were significantly (p < 0.01) correlated with those of total and faecal coliforms, whereas no correlation was found between filamentous fungi and the indicator bacteria of faecal pollution. Significantly higher counts of total and faecal coliforms (p < 0.05), and enterococci (p < 0.001), were found during the months with the higher water temperatures and bather numbers. In the six prefectures, significant differences were observed in the counts of filamentous fungi and yeasts as well as in the counts of all the faecal pollution indicators. The results of this study indicate that coastal water can be a path for contamination of swimmers with yeasts and filamentous fungi and that the pollution indicator microorganisms cannot always predict their presence.

Feces↗
PubMed2004

Carbon use, nitrogen use, and isotopic fractionation of ectomycorrhizal and saprotrophic fungi in natural abundance and 13C-labelled cultures.

Stable isotopes in fruit bodies from field studies have been used to infer ectomycorrhizal or saprotrophic status and to understand carbon and nitrogen use, but few controlled culture studies have correlated source and fungal isotopic patterns. Here, we measured natural abundances of 15N and 13C in ten strains of ectomycorrhizal fungi and seven strains of saprotrophic fungi grown on agar with three different primary carbon sources: glucose, glucose plus malt extract, and potato dextrose agar. Eight fungal strains were also grown using position-specific, 13C-labelled glucose (C-1 through C-6 labelled). Most fungi resembled nitrogen sources in delta 15N, suggesting that growth on agar media minimizes isotopic fractionation on uptake compared to growth on liquid media, and that in general saprotrophic and mycorrhizal fungi process nitrogen similarly. Saprotrophic fungi were more depleted in 13C than ectomycorrhizal fungi on all media, presumably because of assimilation of 13C-depleted, agar-derived carbon. Results on 13C-enriched glucose indicated that saprotrophic fungi obtained up to 45 % of their carbon from the agar substrate. Fungi generally incorporated the individual carbon atoms of glucose in the order, C-4 < C-1 < C-2, C-3, C-5 < C-6, ranging from a mean of 9 % for the C-4 atom to 21 % for the C-6 atom. Based on these incorporation patterns and intramolecular 13C patterns within glucose, differential incorporation of carbon atoms within glucose among fungal taxa contributed less than 1% to isotopic differences among taxa, whereas isotopic fractionation among taxa during metabolism varied up to 4%. Parallel studies of 13C-enriched and natural abundance substrates were crucial to interpreting our results.

Carbon↗
PubMed1999

Degradation of polycyclic aromatic hydrocarbons with three to seven aromatic rings by higher fungi in sterile and unsterile soils.

Seven commercial 3- to 7-ring (R) polycyclic aromatic hydrocarbons (PAH) as well as PAH derived from lignite tar were spiked into 3 soils (0.8 to 9.7% of organic carbon). The disappearance of the original PAH was determined for the freshly spiked soils, for soils incubated for up to 287 d with their indigenous microflora, and for autoclaved, unsterile and pasteurized soils inoculated with basidiomycetous and ascomycetous fungi. Three to 12 d after spiking, 22 to 38% of the PAH could no longer be recovered from the soils. At 287 d, 88.5 to 92.7%, 83.4 to 87.4%, and 22.0 to 42.1% of the 3-, 4-, and 5- to 7-R PAH, respectively, had disappeared from the unsterile, uninoculated soils. In 2 organic-rich sterile soils, the groups of wood- and straw-degrading, terricolous, and ectomycorrhizal fungi reduced the concentration of 5 PAH by 12.6, 37.9, and 9.4% in 287 d. Five- to 7-R PAH were degraded as efficiently as most of the 3- to 4-R PAH. In organic-rich unsterile soils inoculated with wood- and straw-degrading fungi, the degradation of 3- to 4-R PAH was not accelerated by the presence of fungi. The 5- to 7-R PAH, which were not attacked by bacteria, were degraded by fungi to 29 to 42% in optimum combinations of fungal species and soil type. In organic-poor unsterile soil, these same fungi delayed the net degradation of PAH possibly for 2 reasons. Mycelia of Pleurotus killed most of the indigenous soil bacteria expected to take part in the degradation of PAH, whereas those of Hypholoma and Stropharia promoted the development of opportunistic bacteria in the soil, which must not necessarily be PAH degraders. Contemporarily, the contribution of the fungi themselves to PAH degradation may be negligible in the absence of soil organic matter due to the lower production of ligninolytic enzymes. It is concluded that fungi degrade PAH irrespective of their molecular size in organic-rich and wood chip-amended soils which promote fungal oxidative enzyme production.

Biodegradation, Environmental↗
PubMed2001

Prevalence of immunoglobulin E for fungi in atopic children.

BACKGROUND: The prevalence of sensitization to fungi in young atopic patients in relation to age and clinical importance is largely unknown. OBJECTIVE: The aim of this study was to investigate the prevalence of sensitization to different fungi in atopic children in relation to age and other aeroallergens. METHODS: A total of 137 atopic children (male 62%, female 38%; mean age 5 years and 9 months, range 5 months-14 years) were studied. Sera of all patients were routinely tested for total IgE and specific IgE against aeroallergens and milk. Positive sera were also tested for IgE against Alternaria alternata, Aspergillus fumigatus, Cladosporium herbarum and Penicillium chrysogenum, using the Pharmacia Enzyme CAP procedure. RESULTS: In this study in atopic children total IgE showed a significant linear relation with age, whereas specific IgE against outdoor fungi, indoor fungi and house dust mite showed significant non-linearity with age. Prevalence of specific IgE for Cladosporium ranked first, followed closely by Aspergillus and Alternaria. Calculation of the sensitization of indoor and outdoor fungi showed maximum prevalence at 7.8 years, followed by lower values at higher ages. A similar significant relation was also found for Alternaria, while this relation was not significant for the other individual fungi. Specific IgE for indoor and outdoor fungi was associated with the presence of specific IgE for aeroallergen and milk. We found that all children aged 4 years and older showed IgE for house dust mite that did not decline with increasing age. CONCLUSIONS: Sensitization to fungi is prevalent in childhood, with an age-dependent distribution reaching maximum values at 7.7-7.8 years, followed by a decline for all fungal sensitization with increasing age. The importance and relative contribution of fungal sensitization to airway disease, compared with the other allergens, remains to be established.

Adolescent↗
PubMed2000

Diversity and abundance of resupinate thelephoroid fungi as ectomycorrhizal symbionts in Swedish boreal forests.

Resupinate thelephoroid fungi (hereafter called tomentelloid fungi) have a world-wide distribution and comprise approximately 70 basidiomycete species with inconspicuous, resupinate sporocarps. It is only recently that their ability to form ectomycorrhizas (EM) has been realized, so their distribution, abundance and significance as mycobionts in forest ecosystems is still largely unexplored. In order to provide baseline data for future ecological studies of tomentelloid fungi, we explored their presence and abundance in nine Swedish boreal forests in which the EM communities had been analysed. Phylogenetic analyses were used to compare the internal transcribed spacer of nuclear ribosomal DNA (ITS rDNA) sequence data obtained from mycobionts on single ectomycorrhizal tips with that obtained from sporocarps of identified tomentelloid fungi. Five species of Tomentella and one species of Pseudotomentella were identified as ectomycorrhizal fungi. The symbiotic nature of Tomentella bryophila, T. stuposa, T. badia and T. atramentaria is demonstrated for the first time. T. stuposa and Pseudotomentella tristis were the most commonly encountered tomentelloid fungi, with the other species, including T. sublilacina, only being recorded from single stands. Overall, tomentelloid fungi were found in five of the studies, colonizing between 1 and 8% of the mycorrhizal root tips. Two of the five sites supported several tomentelloid species. Tomentelloid fungi appear to be relatively common ectomycorrhizal symbionts with a wide distribution in Swedish coniferous forests. The results are in accordance with accumulating data that fungal species which lack conspicuous sporocarps may be of considerable importance in EM communities.

DNA, Ribosomal↗
PubMed2002

Genetic variation of symbiotic fungi cultivated by the macrotermitine termite Odontotermes formosanus (Isoptera: Termitidae) in the Ryukyu Archipelago.

Fungus-growing termites have a mutualistic relationship with their cultivated fungi. To improve understanding of genetic aspects of this relationship, we examined molecular markers in the fungus-growing termite Odontotermes formosanus and its fungi Termitomyces spp. from the Ryukyu Archipelago. Based on the polymorphic band patterns obtained from arbitrarily primed polymerase chain reaction methods, we constructed cladograms for related colonies of the termites and fungi. The resulting trees indicated that the termites display little genetic variation among the colonies, while the symbiotic fungi consist of two major genetic types. In addition, molecular phylogenetic trees of the symbiotic fungi based on internal transcribed spacer and 18S rDNA suggested that these two types of fungi are different species. We also demonstrated that the fungi comprising the fruiting bodies and fungus combs are identical, and that fungus combs are probably a monoculture within a single termite colony. Our results indicate that horizontal transmission of symbiotic fungi among termite colonies occurred during the evolutionary history of this symbiosis.

Animals↗
PubMed2006

Wild-gathered fungi for health and rural livelihoods.

Fungi are a good source of digestible proteins and fibre, are low in fat and energy and make a useful contribution to vitamin and mineral intake. In terms of current dietary advice, 80 g fungi represent one portion of vegetables. Dried fungi and concentrated extracts are also used as medicines and dietary supplements. Some species show strong anti-tumour and antioxidant activity by enhancing various immune system functions and lowering cholesterol levels. Nevertheless, there are also some safety concerns. Edible species might be mistaken for poisonous ones, high heavy-metal concentrations in wild edible fungi (WEF) are a known source of chronic poisoning and the consumption of WEF can contribute markedly to the radiocaesium intake of human subjects. Some regions of Europe have a strong WEF tradition, especially eastern Europe. In the UK the consumption of wild fungi is considered of minor importance. Only one-third of adults consume fungi (cultivated species and WEF) throughout the UK; the average intake of fungi in the UK is estimated to be 0.12 kg fresh weight per capita per year. At least eighty-two species of wild fungi are recorded as being consumed in the UK, although certain species (e.g. chanterelle (Cantharellus cibarius), cep (Boletus edulis), oyster mushroom (Pleurotus ostreatus)) are favoured over others. Although WEF are not essential components in the daily diet, they are a nutritionally-valuable addition to the range of vegetables consumed, and their role in helping to avert food shortages in less-favoured areas should be definitely considered.

Consumer Product Safety↗
PubMed2000

Evidence from beta-tubulin phylogeny that microsporidia evolved from within the fungi.

Microsporidia are obligate intracellular parasites that were thought to be an ancient eukaryotic lineage based on molecular phylogenies using ribosomal RNA and translation elongation factors. However, this ancient origin of microsporidia has been contested recently, as several other molecular phylogenies suggest that microsporidia are closely related to fungi. Most of the protein trees that place microsporidia with fungi are not well sampled, however, and it is impossible to resolve whether microsporidia evolved from a fungus or from a protistan relative of fungi. We have sequenced beta-tubulins from 3 microsporidia, 4 chytrid fungi, and 12 zygomycete fungi, expanding the representation of beta-tubulin to include all four fungal divisions and a wide diversity of microsporidia. In phylogenetic trees including these new sequences, the overall topology of the fungal beta-tubulins generally matched the expected relationships among the four fungal divisions, although the zygomycetes were polyphyletic in some analyses. The microsporidia consistently fell within this fungal diversification, and not as a sister group to fungi. Overall, beta-tubulin phylogeny suggests that microsporidia evolved from a fungus sometime after the divergence of chytrids. We also found that chytrid alpha- and beta-tubulins are much less divergent than are tubulins from other fungi or microsporidia. In trees in which the only fungal representatives were the chytrids, microsporidia still branched with fungi (i.e., with chytrids), suggesting that the affiliation between microsporidian and fungal tubulins is not an artifact of long-branch attraction.

Animals↗
PubMed1992

Evaluation of filamentous fungi isolated from petals of bean and rapeseed for suppression of white mold.

The influence of filamentous fungi isolated from petals of bean and rapeseed on white mold caused by Sclerotinia sclerotiorum was evaluated. In laboratory trials, macerates of agar plugs containing hyphal fragments of the pathogen in combination with individual fungi were applied onto celery petioles, and subsequent lesion diameters were recorded. The efficacy of 10 fungi exhibiting a spectrum of lesion suppression on celery was correlated with the efficacy of the same fungi in growth-room (r = 0.78, P = 0.005) and greenhouse (r = 0.68, P = 0.032) trials. From 315 isolates of fungi evaluated in the laboratory trials, the 10 most suppressive isolates were selected and evaluated in growth-room trials. Spores of the test fungi were applied onto flowers simultaneously with, and up to 24 h after, inoculation with ascospores of S. sclerotiorum. The most suppressive fungi included isolates of Alternaria alternata, Drechslera sp., Epicoccum purpurascens, Fusarium graminearum, Fusarium heterosporum, and Myrothecium verrucaria. These fungi did not provide consistent control of white mold of bean in a field test repeated four times in 1988. However, Drechslera sp. and E. purpurascens significantly reduced the incidence of white mold in one and two trials, respectively. Combination treatments of A. alternata and Benlate (1.1 kg active ingredient ha-1) suppressed white mold significantly more than either treatment alone in one of four trials.

Anti-Bacterial Agents↗
PubMed2000

Filamentous fungi associated with holothurians from the sea of Japan, off the primorye coast of Russia.

Holothurians (Holothurioidea, Echinodermata) are known to contain triterpene glycosides, which show antifungal activity. Nevertheless, fungi can be isolated from all organs of holothurians. During 1995-1996, mycelial fungi from several Far-Eastern holothurians--Apostichopus japonicus, Eupentacta fraudatrix, Cucumaria japonica--were collected from the Sea of Japan near the coast of Primorye (Russia) and studied. Twenty-seven species of marine fungi, mostly facultative ones belonging to the mitosporic fungi, were isolated from the holothurians and identified. Fungi isolated from the holothurian surface were more diverse and abundant than those from internal organs and coelomic fluids. Of the holothurians studied, Cucumaria japonica was poorest in abundance and diversity of fungi. The fungi Cladosporium brevicompactum and C. sphaerospermum were common in the holothurian coelom. Because of their high proteolytic activity, these fungi may be pathogenic to holothurians. The detritovorus holothurian A. japonicus was shown to modify the fungal assemblages within the marine bottom sediments.

Animals↗
PubMed2005

Phylogeny of certain biocontrol agents with special reference to nematophagous fungi based on RAPd.

A number of phylogenetic studies have been carried out on biocontrol agents having similar biological control activity. However, no work has been carried out to determine the phylogenetic relationship amongst various groups of biological control agents with varied biocontrol properties. Our aim was to derive a phylogenetic relationship between diverse biocontrol agents belonging to the deuteromycetes and determine its correlation with their spore morphology and their biocontrol activity. RAPD was used to assess genomic variability in fungi used as biological control agents which included ten isolates of nematophagous fungi such as Arthrobotrys sp., Duddingtonia sp., Paecilomyces sp. and Verticillium sp., along with two isolates of fungal biocontrol agents such as Trichoderma sp. and two isolates of entomopathogenic fungi including Beauveria sp. A plant pathogenic fungus, Verticillium alboatrum was also included to increase the diversity of Deuteromycetes used. A similarity matrix was created using Jaccard's similarity coefficient & clustering was done using unweighted pair group arithmetic mean method (UPGMA). The final dendogram was created using a combination of two programs, Freetree and TreeExplorer. The phylogenetic tree constructed from the RAPD data showed marked genetic variability among different strains of the same species. The spore morphologies of all these fungi were also studied. The phylogenetic pattern could be correlated with the conidial and conidiophore morphology, a criterion commonly used for the classification of fungi in general and Deuteromycetes in particular. Interestingly, the inferred phylogeny showed no significant grouping based on either their biological control properties or the trapping structures amongst the nematophagous fungi as reported earlier by other workers. The phylogenetic pattern was also similar to the tree obtained by comparing the 18S rRNA sequences from the database. The result clearly indicates that the classical method of classification of these deuteromycete members on the basis of their spore morphology is reliable and could be used for identification of these fungi at species level. The PCR fragment pattern polymorphism exhibited by the various species of a genus and different strains of a species indicates that construction of probes from one or more of these fragments will prove to be useful as a rapid tool for identification of species and strains of nematophagous fungi in future.

Base Sequence↗
PubMed2004

[Fungi in patients with diabetes mellitus type 2: prevalence, species of isolated strains].

In 77 diabetic patients the detection of fungi was carried out in the oral cavity, digestive tract, genital organs and skin lesions. Patient age ranged from 39 to 82 years, with the Body Mass Index (BMI) from 22 to the highest values of 46.5. Diabetes control was assessed by determination of the glucose level in serum after overnight fasting and after lunch, as well as by determination of the HbA(1c) level. Fungi were diagnosed in 61 patients (79.6%). The total of 111 fungal strains were isolated in 319 cultures evaluated from 12 biological materials. Fungal strains were detected in the highest percentage in oral cavity (77.9%), in the lower percentage in anus (33.8%), vagina discharge (11.6%) and the region of vulva (14.3%). Fungi were observed in one focus--exclusively in the oral cavity--in 28 (36.4%) patients, whereas they occurred in multifocal infections in 33 (42.9%) patients. The isolated fungal strains were classified into 4 genera (Candida, Saccharomyces, Trichosporon, Aspergillus) and 12 species. The most frequently detected fungi were C. albicans (55.2%), followed by C. glabrata (12.4%), C parapsilosis (10.5%) and C. tropicalis (9.5%). Relatively low percentage of fungi identified in vagina was associated, among others, with the fact that most of the female patients with diabetes were at the postmenopausal period. In all the patients in whom fungi were isolated from the vagina contents, these fungi were also found in other ontocenoses. The increase in percentage of fungal strains from genera other than Candida in patients with a higher risk is of clinical importance, as some of them are resistant in vitro to azole derivatives e.g. fluconazole. The digestive tract is thought to be the most frequent fungal habitat. A considerable prevalence of fungi, multifocal infections, particularly related to oral cavity and anus, and occurrence of high percentage of strains different from C. albicans species of Candida genus in female patients with type 2 diabetes indicate the necessity of the special mode of diagnostic and therapeutic management.

Adult↗