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1.
Mycologia ; 113(1): 231-244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33327878

RESUMO

Megacoelomyces (type species: Megacoelomyces sanchezii), an ascomycete asexual morph infecting Myrcia fenzliana (Myrtaceae) from the Brazilian Cerrado, is described as a new genus in the Phaeosphaeriaceae (Pleosporales, Dothideomycetes, Ascomycota), based on multilocus phylogeny (three nuclear ribosomal DNA and two protein-coding genes) in addition to morphological (light and scanning electron microscopy) and ecological data.


Assuntos
Classificação , Fungos Mitospóricos , Ascomicetos/classificação , Ascomicetos/citologia , Ascomicetos/genética , Ascomicetos/ultraestrutura , Brasil , DNA Fúngico/genética , DNA Ribossômico/genética , Genes Fúngicos , Microscopia Eletrônica de Varredura , Fungos Mitospóricos/classificação , Fungos Mitospóricos/citologia , Fungos Mitospóricos/genética , Fungos Mitospóricos/ultraestrutura , Myrtaceae/microbiologia , Filogenia
2.
Mycologia ; 109(4): 588-600, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29211626

RESUMO

The genus Cheiromycina is one of the few genera of lichenized hyphomycetes for which no sexual reproductive stages have been observed. The genus includes species from boreal to temperate regions of the Northern Hemisphere where it is found growing on bark or wood. Congeners in Cheiromycina are characterized by a noncorticate thallus, nearly immersed in the substrate and presenting powdery unpigmented sporodochia, and containing chlorococcoid photobionts. The relationships of members of Cheiromycina with other fungi are not known. Here we inferred the phylogenetic placement of Cheiromycina using three loci (nuSSU, nuLSU, and mtSSU) representing C. flabelliformis, the type species for the genus, C. petri, and C. reimeri. Our results revealed that the genus Cheiromycina is found within the family Malmideaceae (Lecanorales) where members formed a monophyletic clade sister to the genera Savoronala and Malmidea. This phylogenetic placement and the relationships of Cheiromycina with other lichenized hyphomycetous taxa are here discussed.


Assuntos
Ascomicetos/classificação , Líquens/microbiologia , Fungos Mitospóricos/classificação , Filogenia , Ascomicetos/citologia , Ascomicetos/genética , DNA Fúngico/genética , Europa (Continente) , Fungos Mitospóricos/citologia , Fungos Mitospóricos/genética , Casca de Planta/microbiologia , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Estados Unidos
3.
Antonie Van Leeuwenhoek ; 108(5): 1023-35, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26363911

RESUMO

Nearly 100 years after its first discovery, Diploöspora rosea was detected on biologically damaged parchment paper in Rome, Italy and isolated from house dust collected in Micronesia. The isolation of this culture permitted morphological study of colony characters, conidium and conidiophore development, and phylogenetic investigations using sequences of nuc 18S rDNA, internal transcribed spacers, and 28S rDNA. The results indicate that D. rosea is an onygenalean fungus, of uncertain taxonomic position, basal or sister to the Gymnoascaceae. Based on observations of the parchments using SEM-Energy Dispersive Spectroscopy, we speculate that the fungus occurs in archival and domestic environments subject to periodic wetting. Its ability to grow on all low water activity media used in the study, including malt extract agar amended with 60% sucrose, confirms its xerophilic nature.


Assuntos
DNA Espaçador Ribossômico , Fungos Mitospóricos/classificação , Fungos Mitospóricos/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Código de Barras de DNA Taxonômico , Fungos Mitospóricos/citologia , Fungos Mitospóricos/ultraestrutura , Filogenia
4.
Mycoses ; 58(2): 113-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25591072

RESUMO

We report the first case of onychomycosis caused by Onychocola canadensis in Estonia. We believe that the number of nail infections caused by this fungus is underestimated due to the current diagnostic algorithm of non-dermatophytic onychomycosis. The need to define categories and criteria for 'proven' and 'probable' non-dermatophyte mold infections to promote more extensive studies in the future is also discussed.


Assuntos
Dermatoses do Pé/microbiologia , Fungos Mitospóricos/isolamento & purificação , Onicomicose/microbiologia , Onygenales/isolamento & purificação , Estônia , Feminino , Humanos , Pessoa de Meia-Idade , Fungos Mitospóricos/citologia , Onygenales/citologia
5.
Mycologia ; 104(6): 1510-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22778169

RESUMO

Two new species of aquatic hyphomycetes in the genus Tricladium are described from streams in Alaska, USA. Both species were isolated from submerged decaying sedges. Tricladium kelleri has blackish colonies and typical tricladioid conidia formed on sympodial conidiogenous cells. Tricladium alaskense has conidia with fine elements and 0-4 lateral branches; conidia are formed on sympodial conidiogenous cells. The two species are compared to other species in the genus and related genera using morphological characters and/or rDNA sequencing data (ITS and 28S). Molecular phylogenetic analysis placed both species in the Helotiales.


Assuntos
Carex (Planta)/microbiologia , Fungos Mitospóricos/classificação , Filogenia , Esporos Fúngicos/citologia , Alaska , Sequência de Bases , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fungos Mitospóricos/citologia , Fungos Mitospóricos/genética , Fungos Mitospóricos/isolamento & purificação , Dados de Sequência Molecular , Rios , Análise de Sequência de DNA , Esporos Fúngicos/classificação , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação
6.
Biocontrol Sci ; 16(4): 139-47, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22190436

RESUMO

Scolecobasidium, generally found in outdoor samples, were isolated from detergent-rich indoor environments. The isolates from bathrooms and washing machines, because of their exposure to detergents, might be genetically and biologically distinct from outdoor isolates. In this study, 11 Scolecobasidium isolates from detergent-rich indoor environments were examined to find the genetic and biological differences between the indoor and outdoor isolates. One isolate from a wall of a soap factory, showing similar conidia morphology with S. constricta, was phylogenetically distinct from the other Scolecobasidium spp. The 10 isolates from washing machines and bathrooms were identified as S. humicola, but these were classified into 2 groups that differed from the reference strain of S. humicola from leaves. All 11 isolates and the 4 reference strains of S. constricta and S. humicola grew on the medium containing sodium oleate and polyoxyethylene-(9)-lauryl ether, but the reference strains of the other Scolecobasidium spp. grew only on the medium containing sodium oleate. The results showed that S. humicola and S. constricta could utilize both surfactants generally included in soaps or synthetic detergents as nutrients. A further implication is that the genetic variation found in the S. humicola isolates from detergent-rich indoor environments can occur as a result of adaptation to such an environment.


Assuntos
Microbiologia Ambiental , Fungos Mitospóricos/genética , Detergentes , Fungos Mitospóricos/classificação , Fungos Mitospóricos/citologia , Fungos Mitospóricos/crescimento & desenvolvimento
7.
Semin Respir Crit Care Med ; 32(6): 703-16, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22167398

RESUMO

Invasive mold infections affecting the lungs are increasing in incidence and diversity. Severely immunocompromised patients are particularly vulnerable to infection from unusual, normally nonpathogenic fungi that are found naturally in the environment. Certain fungi such as Scedosporium and the dematiaceous fungi also cause lung disease in hosts without overt immune compromise. The impacts of these emerging pathogens range from airway colonization to locally invasive lung, and disseminated, disease. Diagnosis requires isolation and identification of the etiologic agent by either or both phenotypic and molecular biology methods. Evidence of tissue invasion on histopathology is often required to distinguish infection from colonization. Diagnostic imaging techniques are nonspecific, and there are no reliable serological biomarkers of infection. Many rare molds and yeasts demonstrate reduced in vitro susceptibility to antifungal agents. Although amphotericin B formulations remain clinically useful for many of these infections, voriconazole and posaconazole are more effective for some of these difficult-to-treat pathogens. Surgical resection of diseased tissue and support of the host immune system are often required to optimize outcomes.


Assuntos
Hospedeiro Imunocomprometido , Pneumopatias Fúngicas , Fungos Mitospóricos , Leveduras , Antifúngicos/uso terapêutico , Humanos , Hialoifomicose/diagnóstico , Hialoifomicose/tratamento farmacológico , Hialoifomicose/epidemiologia , Hialoifomicose/fisiopatologia , Pneumopatias Fúngicas/diagnóstico , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/epidemiologia , Pneumopatias Fúngicas/fisiopatologia , Fungos Mitospóricos/citologia , Fungos Mitospóricos/imunologia , Fungos Mitospóricos/patogenicidade , Feoifomicose/diagnóstico , Feoifomicose/tratamento farmacológico , Feoifomicose/epidemiologia , Feoifomicose/fisiopatologia , Leveduras/citologia , Leveduras/imunologia , Leveduras/patogenicidade , Zigomicose/complicações , Zigomicose/diagnóstico , Zigomicose/tratamento farmacológico , Zigomicose/epidemiologia , Zigomicose/imunologia , Zigomicose/fisiopatologia
8.
Nat Prod Res ; 24(8): 767-74, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20432159

RESUMO

Microbial transformation of beta-amyrin by growing cells of the fungus Lecanicillium muscarinium (former Cephalosporium aphidicola) was successfully accomplished after 15 days of incubation with orbital shaking at 120 rpm. Two products purified by column chromatography were identified by 1H and 13C mono- and bi-dimensional nuclear magnetic resonance as 3beta-hydroxy-olean-12-en-11-one and 11alpha,12alpha-oxidotaraxerol; these later formed new compounds formed by an interesting oxidative rearrangement of the starting material, probably via an initial hydroxylation at C-11.


Assuntos
Fungos Mitospóricos/citologia , Fungos Mitospóricos/metabolismo , Ácido Oleanólico/análogos & derivados , Biotransformação , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/metabolismo , Oxirredução
9.
Am J Clin Pathol ; 132(1): 86-93, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19864238

RESUMO

Acute fungal sinusitis is a life-threatening infection affecting immunocompromised patients. Historically, the most commonly recovered fungi are Aspergillus and Mucor. The extent of potentially disfiguring debridement surgery is grossly determined by the appearance of bleeding at the margins, signifying viable tissue and the absence of fungus. Requests for frozen section may concern the initial diagnosis and the intraoperative verification of margin status. In 12 patients with acute fungal sinusitis, frozen section was used in 8. Routine H&E stains demonstrated fungal hyphae in necrotic debris in 5 cases, often associated with vascular and perineural invasion. All patients underwent extensive sinus debridement, including orbital exenteration in 2 cases. All 12 patients died, 9 of fungal sepsis. Autopsy in 3 patients showed pulmonary involvement (2 cases), intracranial spread (1 case), and no residual fungus (1 case). Inexperience with organism recognition is surmountable. Frozen section has a role in the management of this devastating disease.


Assuntos
Secções Congeladas/métodos , Fungemia/diagnóstico , Fungos Mitospóricos/isolamento & purificação , Sinusite/diagnóstico , Sinusite/microbiologia , Adulto , Idoso , Chicago/epidemiologia , Desbridamento , Feminino , Fungemia/mortalidade , Fungemia/cirurgia , Humanos , Hifas/citologia , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Fungos Mitospóricos/citologia , Sinusite/cirurgia , Taxa de Sobrevida
10.
Mycologia ; 101(3): 417-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19537214

RESUMO

Piricaudiopsis punicae sp. nov., P. rosae sp. nov. and P. rhaphidophorae sp. nov., occurring respectively on dead branches of Punica granatum, Rosa chinensis and Rhaphidophora decursiva were collected from tropical forest in southern China. They differ from the three previously described Piricaudiopsis species in conidial morphology and proliferation of the conidiogenous cell. The presence or absence of percurrent proliferation of the conidiogenous cells and conidial appendages and the height of conidia are recognized as important characters in the delimitation of species of Piricaudiopsis. A key to Piricaudiopsis species is provided.


Assuntos
Fungos Mitospóricos/classificação , Araceae/microbiologia , China , Ecossistema , Lythraceae/microbiologia , Fungos Mitospóricos/citologia , Fungos Mitospóricos/isolamento & purificação , Fungos Mitospóricos/fisiologia , Rosa/microbiologia , Especificidade da Espécie , Esporos Fúngicos/citologia , Esporos Fúngicos/isolamento & purificação , Árvores/microbiologia
11.
J Clin Lab Anal ; 23(3): 161-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19455635

RESUMO

Most fungi occur in nature and utilize simple sources of carbohydrates and nitrogen for growth. Sabouraud's dextrose agar has been an ideal medium for primary isolation of fungi from clinical specimens, but for specimens from nonsterile sites or heavily contaminated ones, it has been necessary to include inhibitory substances such as antibiotics like chloramphenicol (antibacterial) and cycloheximide (antifungal). The problems we have in the our laboratory owing to frequent contamination of cultures and the delays in the procurement of cycloheximide have stimulated a search for alternatives in our local environment to enhance effective laboratory diagnoses of fungal infections. Purified extracts of the leaves and bark of Jatropha curcas and Moringa oleifera (common plants in our locality) were tested against clinical isolates of fungi at various concentrations to determine the minimum inhibitory concentration at which common fungal contaminants are inhibited, without affecting the growth of the pathogenic fungi sought for. At a concentration of 0.75 mg ml(-1) contaminants were totally inhibited by the leaf extracts. The bark extracts did not inhibit any fungus even at higher concentrations. From the results it was evident that the leaf extracts of both plants have potentials for use as inhibitory substances in culture media against contaminant fungi including Aspergillus spp., Penicillium spp., etc. J. curcas and M. oleifera are very common plants in our locality. They can be obtained at almost no cost and at any time needed. The benefits of these findings to mycology laboratories in a developing country are enormous.


Assuntos
Antifúngicos/farmacologia , Meios de Cultura/química , Jatropha/química , Fungos Mitospóricos/efeitos dos fármacos , Moringa oleifera/química , Micoses/diagnóstico , Extratos Vegetais/farmacologia , Aspergillus/citologia , Aspergillus/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cicloeximida/farmacologia , Técnicas e Procedimentos Diagnósticos , Humanos , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/citologia , Micoses/microbiologia , Penicillium/citologia , Penicillium/efeitos dos fármacos , Folhas de Planta/química , Trichophyton/citologia , Trichophyton/efeitos dos fármacos
12.
Artigo em Inglês | MEDLINE | ID: mdl-18583793

RESUMO

Rare molds are increasingly emerging as a cause of deep and invasive fungal infections. We report here a rare case of cutaneous phaeohyphomycosis of the lower limbs due to Alternaria alternata associated with extra-ungual localization of Scopulariopsis brevicaulis. Diagnosis was made based on repeated, direct, microscopic mycological and histological examinations. The study revealed hyphae and fungal cells in a granulomatous dermal infiltrate. Identification of the molds was based on macroscopic appearance on culture of samples from the lesions on Sabouraud's dextrose agar and microscopic appearance on Lactophenol cotton blue following slide culture.


Assuntos
Alternaria/isolamento & purificação , Dermatomicoses/microbiologia , Dermatoses da Perna/microbiologia , Fungos Mitospóricos/isolamento & purificação , Adulto , Alternaria/citologia , Dermatomicoses/diagnóstico , Evolução Fatal , Feminino , Humanos , Imunocompetência , Dermatoses da Perna/diagnóstico , Fungos Mitospóricos/citologia , Pele/microbiologia
13.
Lett Appl Microbiol ; 45(5): 508-14, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17958556

RESUMO

AIMS: To investigate antifungal activity of a novel compound (named as CF66I provisionally) against plant pathogenic fungi, mainly including Fusarium sp., Colletotrichum lindemuthianum, Rhizoctonia solani, etc. METHODS AND RESULTS: Minimal inhibition concentrations (MIC) and minimal fungicidal concentrations (MFC) of CF66I for each fungi were determined using serial broth dilution method. The data demonstrated MIC ranged from 2.5 to 20.0 microg ml(-1) and MFC were shown at levels of < or =7.5 microg ml(-1) except Fusarium sp. With reverse microscopy, profound morphological alterations of fungal cells were observed after exposure to CF66I. Conidiospores were completely inhibited, and protoplasm aggregated to form chalamydospores because of the changes of cell permeability. Some chalamydospores were broken, suggesting the compound probably possessed strong ability of damaging the cell wall. In addition, CF66I was investigated for its antifungal stability against Curvularia lunata. The results showed CF66I kept strong fungi-static activity over-wide pH range (pH 4-9) and temperature range (from -70 to 120 degrees C). CONCLUSIONS: The compound CF66I exhibited strong and stable broad-spectrum antifungal activity, and had a significant fungicidal effect on fungal cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Results from prebiocontrol evaluations performed to date are probably useful in the search for alternative approaches to controlling serious plant pathogens.


Assuntos
Amidas/farmacologia , Antifúngicos/farmacologia , Burkholderia cepacia/metabolismo , Fungos Mitospóricos/efeitos dos fármacos , Doenças das Plantas/microbiologia , Amidas/isolamento & purificação , Antifúngicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/citologia , Temperatura
14.
Mycologia ; 99(1): 24-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17663120

RESUMO

Attachment of conidia on leaves is a critical first step in the life cycle of aquatic hyphomycetes in streams. In a first series of microcosm experiments, attachment success of three common aquatic hyphomycete species differing in conidial shape (compact, filiform and tetraradiate) was determined on two leaf species, black alder and downy oak. Fungal species identity and leaf surface structure significantly affected conidial attachment after 24 h. The lower sides of oak leaves with extensive tufts trapped 2.4-8.8 more conidia than the upper sides of oak leaves and both sides of alder leaves. In a second experiment with seven fungal species, attachment success of two species with tetraradiate conidia was much greater than that of two other tetraradiate and three compact conidia, which all had similar attachment success. The species with the largest spores was also the most successful, but this pattern was not consistent across the size range of tested conidia. These results highlight the importance of leaf surface structure, possibly conidial shape and size and additional properties of aquatic hyphomycete conidia in determining attachment success on leaves and they point to the potential role of these factors in structuring fungal communities on decomposing leaves in streams.


Assuntos
Adesão Celular/fisiologia , Fungos Mitospóricos/fisiologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/microbiologia , Esporos Fúngicos/citologia , Esporos Fúngicos/fisiologia , Fungos Mitospóricos/citologia , Rios , Microbiologia da Água
15.
Mycologia ; 98(4): 628-36, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17139856

RESUMO

Foam from eight streams in boreal and mixed-wood forests in Québec were sampled in early and late fall 2002 to evaluate the biodiversity of their aquatic hyphomycete communities. Two regions were studied: 53-54 degrees N and 46-49 degrees N. A total of 54 species were identified. Twenty taxa were found only in the northern region, and four were unique to the southern region. A new aquatic hyphomycete, Dwayaangam colodena sp. nov., was found mostly in northern streams. It is described along with its taxonomic position.


Assuntos
Fungos Mitospóricos/classificação , Rios/microbiologia , Biodiversidade , DNA Espaçador Ribossômico/genética , Geografia , Fungos Mitospóricos/citologia , Fungos Mitospóricos/isolamento & purificação , Fungos Mitospóricos/fisiologia , Filogenia , Quebeque , Esporos Fúngicos/isolamento & purificação , Esporos Fúngicos/fisiologia , Árvores
16.
FEMS Microbiol Lett ; 264(1): 117-24, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17020557

RESUMO

Amino acid derivatives of monascus pigments were produced by fermentation, and their antimicrobial activities were determined. Thirty-nine l- and d-forms of amino acids were added as a precursor to the fermentation medium for derivation of pigments. Derivatives with L-Phe, D-Phe, L-Tyr, and D-Tyr exhibited high activities against Gram(+) and Gram(-) bacteria with MIC values of c. 4-8 microg mL(-1). The control red pigment exhibited minimal inhibitory concentration (MIC) values higher than 32 microg mL(-1). Derivatives with L-Asp, D-Asp, L-Tyr, and D-Tyr were effective against the filamentous fungi Aspergillus niger, Penicillium citrinum, and Candida albicans. Monascus derivatives of amino acids having a phenyl ring like Phe and Tyr derivatives showed high antimicrobial activities. Incubation of the l-Phe derivative with Bacillus subtilis caused cells to aggregate with formation of pellets. Easy adsorption of the L-Phe pigment derivative to the surface of Escherichia coli cells was observed via SEM and TEM. Addition of monascus pigment derivatives decreased the oxygen uptake rate of E. coli in culture. The antimicrobial activities of pigment derivatives are considered to be related to the reduced availability of oxygen for the cells adsorbed with pigment.


Assuntos
Aminoácidos/metabolismo , Anti-Infecciosos/farmacologia , Monascus/química , Pigmentos Biológicos/farmacologia , Adsorção , Aminoácidos/química , Anti-Infecciosos/isolamento & purificação , Fermentação , Bactérias Gram-Negativas/citologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/citologia , Bactérias Gram-Positivas/efeitos dos fármacos , Fungos Mitospóricos/citologia , Fungos Mitospóricos/efeitos dos fármacos , Monascus/metabolismo , Oxigênio/química , Pigmentos Biológicos/isolamento & purificação , Pigmentos Biológicos/metabolismo
17.
Prikl Biokhim Mikrobiol ; 42(4): 489-92, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17022462

RESUMO

The ability of deuteromycetes of the genera Penicillium, Aspergillus, and Botrytis to retain collagenolytic activity was studied after both 2 and 10 years of storage on a Czapek medium under a layer of mineral oil at 4 degrees C, as well as in silica gel granules at 20 and -60 degrees C. The enzymatic activity of several species, including Botrytis terrestris, Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum, was retained under both conditions of storage. Aspergillus repens retained enzymatic activity only if stored under a layer of mineral oil. The viability of conidia and the collagenolytic activity of Botrytis terrestris, P. janthinellum, P. chrysogenum, and Penicillium citrinum, maintained on silica gel for 10 years, depended on the storage temperature. The viability of the test strains improved after storage on a silica gel at -60 degrees C. A strain of Aspergillus repens lost its ability to dissolve collagen at various storage temperatures on the silica gel. The index of lysis for three strains of Penicillium deuteromycetes (Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum) increased after a 10-year storage on silica gel at -60 degrees C.


Assuntos
Colágeno/metabolismo , Criopreservação , Fungos Mitospóricos/enzimologia , Colágeno/química , Criopreservação/métodos , Fungos Mitospóricos/química , Fungos Mitospóricos/citologia , Sílica Gel , Dióxido de Silício/química , Fatores de Tempo
18.
Mycopathologia ; 162(2): 115-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16897590

RESUMO

The aim of this study was to select virulent strains of microfungi against Leucoagaricus gongylophorus, a symbiotic fungus cultivated by leaf-cutting ants. The results from in vitro assays showed that microfungal strains had a variable and significant impact on the colony development of L. gongylophorus. Specifically, Trichoderma harzianum, Escovopsis weberi CBS 810.71 and E. weberi A088 were more effective, inhibiting the L. gongylophorus colonies by 75, 68 and 67%, respectively (P < 0.05) after 15 days. Strain E. weberi A086 and Acremonium kiliense were less effective: 43 and 26%, respectively (P < 0.05). In spite of the current negative perspective of a microbiological control approach for these ants, the present work discusses the possibility of using mycopathogenic fungi for the control of these insects, and points out the importance of encouraging more studies in this area.


Assuntos
Formigas/microbiologia , Basidiomycota/fisiologia , Controle de Insetos/métodos , Fungos Mitospóricos/fisiologia , Animais , Basidiomycota/citologia , Fungos Mitospóricos/citologia , Simbiose
19.
Can J Microbiol ; 52(7): 643-50, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16917520

RESUMO

Phialocephala fortinii is a dark septate fungal endophyte that colonizes roots of many host species. Its effect on plant growth varies from being pathogenic to beneficial. The basic biology of this species has received little research, and thus the main objectives of this study were to determine cytological features of hyphae, including the nature of the vacuolar system, and whether polyphosphate was present in vacuoles. Both living hyphae and hyphae that had been rapidly frozen and freeze substituted before embedding were studied. A complex system of vacuoles, including a motile tubular vacuolar system, elongated vacuoles, and spherical vacuoles, was demonstrated in living hyphae by the fluorescent probe Oregon Green 488 carboxylic acid diacetate, using laser scanning confocal microscopy. The motile tubular vacuolar system was more prevalent at the hyphal tip than in more distal regions, whereas elongated vacuoles and spherical vacuoles were more abundant distal to the tip. All vacuoles contained polyphosphate as shown by labelling embedded samples with recombinant polyphosphate binding domain of Escherichia coli exopolyphosphatase, containing Xpress tag at the N-terminal end, followed by anti-Xpress antibody and a secondary antibody conjugated either to a fluorescent probe for laser scanning confocal microscopy or colloidal gold for transmission electron microscopy. The polyphosphate was dispersed in vacuoles. This was confirmed by staining embedded samples with 4',6-diamidino-2-phenylindole and viewing with UV light using epifluorescence microscopy. These cytological methods showed that the tubular vacuolar system had lower concentrations of polyphosphate than the spherical vacuoles. Lipid bodies were present around vacuoles.


Assuntos
Hifas/química , Hifas/citologia , Fungos Mitospóricos/química , Fungos Mitospóricos/citologia , Polifosfatos/análise , Vacúolos/química , Ácidos Carboxílicos , Imuno-Histoquímica , Lipídeos/análise , Microscopia Confocal
20.
Med Mycol ; 44(1): 33-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16805091

RESUMO

PCR amplification and sequencing of two separate regions of the nuclear ribosomal repeat region revealed that Polycytella hominis, a hyphomycete isolated from a human case of mycetoma, was genetically indistinguishable from Scedosporium apiospermum (the anamorph of Pseudallescheria boydii). These organisms also exhibited remarkably similar susceptibility profiles to common antifungal agents. P. hominis is thus likely to be a mutant of S. apiospermum showing abnormalities of sporulation, for which a possible mechanism is discussed. Polycytella hominis should thus be regarded as a synonym of Scedosporium apiospermum.


Assuntos
Fungos Mitospóricos/classificação , Fungos Mitospóricos/genética , Mutação , Scedosporium/classificação , Scedosporium/genética , Antifúngicos/farmacologia , Ascomicetos , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Fungos Mitospóricos/citologia , Fungos Mitospóricos/efeitos dos fármacos , Dados de Sequência Molecular , Filogenia , Scedosporium/citologia , Scedosporium/efeitos dos fármacos , Análise de Sequência de DNA , Homologia de Sequência , Esporos Fúngicos/genética
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