RESUMEN
Light influences developmental pathways in fungi. Recent transcriptomic and biochemical analyses have demonstrated that light influences the metabolism of a white-rot basidiomycete Cerrena unicolor. However, the expression profile of genes involved in the growth and development, or micromorphological observations of the mycelium in response to variable lighting and culturing media, have not performed. We aim to reveal the effect of light and nutrients on C. unicolor growth and a potential relationship between the culture medium and lighting conditions on fungus micromorphological structures. Confocal laser scanning microscopy and scanning electron microscopy were employed for morphological observations of C. unicolor mycelium cultivated in red, blue, green, and white light and darkness on mineral and sawdust media. A comprehensive analysis of C. unicolor differentially expressed genes (DEGs) was employed to find global changes in the expression profiles of genes putatively involved in light-dependent morphogenesis. Both light and nutrients influenced C. unicolor growth and development. Considerable differences in the micromorphology of the mycelia were found, which were partially reflected in the functional groups of DEGs observed in the fungus transcriptomes. A complex cross-interaction of nutritional and environmental signals on C. unicolor growth and morphology was suggested. The results are a promising starting point for further investigations of fungus photobiology.
Asunto(s)
Basidiomycota/ultraestructura , Micelio/ultraestructura , Nutrientes/farmacología , Polyporaceae/ultraestructura , Basidiomycota/genética , Basidiomycota/crecimiento & desarrollo , Basidiomycota/efectos de la radiación , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Regulación Fúngica de la Expresión Génica/efectos de la radiación , Luz , Metabolismo/efectos de los fármacos , Metabolismo/efectos de la radiación , Microscopía Confocal , Micelio/genética , Micelio/crecimiento & desarrollo , Micelio/efectos de la radiación , Polyporaceae/efectos de los fármacos , Polyporaceae/genética , Polyporaceae/efectos de la radiaciónRESUMEN
Four fungal isolates: Simplicillium chinense (iso 9, accession no. KX425621), Penicillium simplicissimum (iso 10, KP713758), Trichoderma asperellum (iso 11, KP792512), and Coriolopsis sp. (1c3, KM403574) were subjected to a series of induced-tolerance training under high metal concentrations to determine if greater tolerance could be achieved from constant exposure to such conditions. Adaptive tolerance assay (Tolerance Index, TI) and Field-Emission Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) characterized their metal tolerance. "Untrained" S. chinense, P. simplicissimum and T. asperellum showed tolerance towards 4000-4500ppm Al(III) (TI: 0.64-0.71), 1000ppm Cr(III) (0.52-0.83) and Pb(II) (0.32-0.88). With tolerance training, tolerance towards 2000-6000ppm Al(III), 500-3000ppm Pb(II) and 2000-3000ppm Cr(III) were achieved (TI: 0.01-0.82) compared to untrained cultures (0.00-0.59). In contrast, tolerance training for Coriolopsis sp. and P. simplicissimum was less successful, with TI values similar or lower than untrained cultures. SEM-EDX analysis proposed biosorption and bioaccumulation as mechanisms for metal removal. The latter was demonstrated with the removal of Cr(III) and Pb(II) by S. chinense (12.37 and 11.52mgg-1, respectively) and T. asperellum (10.44 and 7.50mgg-1). Induced-tolerance training may render benefit in the long run, but this delicate approach is suggestively species and metal dependent.
Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Farmacorresistencia Fúngica , Hypocreales/efectos de los fármacos , Metales/toxicidad , Penicillium/efectos de los fármacos , Polyporaceae/efectos de los fármacos , Trichoderma/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Hypocreales/fisiología , Hypocreales/ultraestructura , Metales/aislamiento & purificación , Microscopía Electrónica de Rastreo , Penicillium/fisiología , Penicillium/ultraestructura , Polyporaceae/fisiología , Polyporaceae/ultraestructura , Trichoderma/fisiología , Trichoderma/ultraestructura , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/metabolismoRESUMEN
Dichomitus squalens efficiently decolorized both Orange G and Remazol Brilliant Blue R (RBBR) at concentrations of 0.5gl(-1) and 3gl(-1) in static and shaken culture and also on solid medium within 14d. The presence of the dyes in the culture medium mostly caused a decrease in biomass production and in growth rate, which was more significant in the case of RBBR. After 14d of cultivation, electron microscopy showed substantial morphological changes in mycelia of D. squalens growing in media containing dyes. The hyphae deformations were more intensively manifested in solid media than in liquid culture. In all the cases, the morphological changes were more prominent in the presence of RBBR. Higher concentrations of both dyes brought about more intensive changes. The toxicity of synthetic dyes Orange G and RBBR was tested using a bioassay based on the growth inhibition of duckweed Lemna minor. Two endpoints such as the number of fronds and their weight were studied during the bioassay. The results showed higher toxicity of RBBR than that of Orange G. The toxicity of both dyes decreased after the decolorization process.
Asunto(s)
Antraquinonas , Compuestos Azo , Polyporaceae , Contaminantes Químicos del Agua , Antraquinonas/química , Antraquinonas/toxicidad , Araceae/efectos de los fármacos , Araceae/crecimiento & desarrollo , Compuestos Azo/química , Compuestos Azo/toxicidad , Biodegradación Ambiental , Biomasa , Hifa/efectos de los fármacos , Hifa/crecimiento & desarrollo , Hifa/ultraestructura , Microscopía Electrónica , Polyporaceae/efectos de los fármacos , Polyporaceae/crecimiento & desarrollo , Polyporaceae/ultraestructura , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidadRESUMEN
Forty-two dikaryotic and 42 monokaryotic isolates, and 34 pairings were examined by horizontal polyacrylamide gel electrophoresis (PAGE) for six enzymatic activities, viz. EST, 6PGD, IDH, MDH, SHDH and SOD. 44 bands were analysed. Numerical analysis of the isoenzymatic patterns was undertaken and compared with those from morphological characters. The analysis of six enzymatic systems showed the existence of four monomorphic systems (IDH, MDH, SHDH and SOD). The sterease system (EST) appears to be polymorphic in Polyporus ciliatus and in populations of P. tenuiculus from Argentina, being monomorphic in the remaining species studied. The 6PGD system is polymorphic in P. tucumanensis and monomorphic in the other species. Predominance of monomorphic enzymes and a clear distribution of the electromorphs among the species, indicates that isoenzymatic analysis is a good taxonomic tool within Polyporus. The low intraspecific variability allowed the use of interspecific differences to separate species. Numerical analysis showed a good correlation between morphological and molecular characters. In the isoenzymatic phenogram the similarity index is high only among very close species, showing a stressed separation of species.
Asunto(s)
Isoenzimas/análisis , Polyporaceae/clasificación , Polyporaceae/enzimología , Oxidorreductasas de Alcohol/análisis , Electroforesis en Gel de Poliacrilamida , Esterasas/análisis , Isocitrato Deshidrogenasa/análisis , Malato Deshidrogenasa/análisis , Técnicas de Tipificación Micológica , Fosfogluconato Deshidrogenasa/análisis , Polyporaceae/genética , Polyporaceae/ultraestructura , América del Sur , Superóxido Dismutasa/análisisRESUMEN
The enzyme oxalate oxidase was identified in mycelial extracts of the basidiomycete Ceriporiopsis subvermispora and thereafter purified to homogeneity. The purification procedure included only three steps: Q-Sepharose chromatography, precipitation at pH 3.0, and phosphocellulose chromatography. The enzyme is a 400-kDa homohexamer, as determined by gel permeation in Sephadex G-200 and SDS-polyacrylamide gel electrophoresis. Isoelectrofocusing revealed a pI of 4.2. Optimal activity was obtained at pH 3.5 and at 45 degrees C. The purified enzyme has Km and kcat values of 0.1 mM and 88 s-1, respectively. It is highly specific for oxalate, although it is inhibited at concentrations of this substrate above 2.5 mM. Hystochemistry studies conducted over mycelium slices showed reactions products in both endocellular and periplasmic associated elements. A possible connection between the intracellular metabolism of oxalate and the extracellular ligninolytic activity of the fungus is proposed.
Asunto(s)
Oxidorreductasas/química , Oxidorreductasas/aislamiento & purificación , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Polyporaceae/enzimología , Activación Enzimática , Histocitoquímica , Microscopía Electrónica , Oxidorreductasas/fisiología , Proteínas de Plantas/fisiología , Polyporaceae/ultraestructura , Fracciones Subcelulares/enzimología , Fracciones Subcelulares/ultraestructuraRESUMEN
The ligninolytic fungus Pleurotus eryngii grown in liquid medium secreted extracellular polysaccharide (87% glucose) and the H2O2-producing enzyme aryl-alcohol oxidase (AAO). The production of both was stimulated by wheat-straw. Polyclonal antibodies against purified AAO were obtained, and a complex of glucanase and colloidal gold was prepared. With these tools, the localization of AAO and extracellular glucan in mycelium from liquid medium and straw degraded under solid-state fermentation conditions was investigated by transmission electron microscopy (TEM) and fluorescence microscopy. These studies revealed that P. eryngii produces a hyphal sheath consisting of a thin glucan layer. This sheath appeared to be involved in both mycelial adhesion to the straw cell wall during degradation and AAO immobilization on hyphal surfaces, with the latter evidenced by double labelling. AAO distribution during differential degradation of straw tissues was observed by immunofluorescence microscopy. Finally, TEM immunogold studies confirmed that AAO penetrates the plant cell wall during P. eryngii degradation of wheat straw.
Asunto(s)
Oxidorreductasas de Alcohol/metabolismo , Glucanos/metabolismo , Polyporaceae/enzimología , Polyporaceae/metabolismo , Biodegradación Ambiental , Pared Celular/enzimología , Pared Celular/metabolismo , Celulasa/inmunología , Celulasa/metabolismo , Fermentación , Microscopía Fluorescente , Microscopía Inmunoelectrónica , Polyporaceae/ultraestructura , Triticum/microbiologíaRESUMEN
Six tyrosinase isozymes were purified from the browned gill of the fruiting body of Lentinus edodes by ammonium sulfate fractionation, DEAE-Sephacel and Q-Sepharose column chromatography, and partially denaturing SDS-PAGE. At the step of Q-Sepharose column chromatography, two active fractions (A and B) were obtained. Each fraction was separated to three further fractions, A1, A2, and A3, and B1, B2, and B3, respectively, by partially denaturing SDS-PAGE. All these isozymes consisted of two types of polypeptides: alpha polypeptide (A alpha or B alpha) and either beta (A beta or B beta) or gamma polypeptide (A gamma or B gamma). The alpha polypeptide contained the consensus amino acid sequence of the active site of known tyrosinases, which is considered to act as a catalytic subunit. From the results of peptide mapping and the amino acid composition, A alpha and B alpha polypeptides were considered to be different proteins. The kinetic properties of the purified tyrosinase isozymes differed greatly according to whether they contained beta or gamma polypeptide, indicating these polypeptides to be a possible regulatory subunit.
Asunto(s)
Isoenzimas/aislamiento & purificación , Monofenol Monooxigenasa/aislamiento & purificación , Polyporaceae/enzimología , Secuencia de Aminoácidos , Aminoácidos/análisis , Conservación de Alimentos , Isoenzimas/química , Datos de Secuencia Molecular , Monofenol Monooxigenasa/química , Polyporaceae/ultraestructura , Homología de Secuencia de AminoácidoRESUMEN
The septal complex in hyphae of Hirshioporus pargamenus (Fr.) Bond. & Sing. is generally similar to that described for other Homobasidiomycetes. A noteworthy distinction is the presence of imperforate parenthesomes. A dark line is frequently observed in the inner matrix of the parenthesome. We suggest that this line is an image produced by the overlapping of folded, opposing membranes differentiated from the wall endoplasmic reticulum.
Asunto(s)
Basidiomycota/ultraestructura , Polyporaceae/ultraestructura , Pared Celular/ultraestructura , Retículo Endoplásmico/ultraestructura , Uniones Intercelulares/ultraestructuraRESUMEN
Necortrophic mycoparasitism by Hirschioporus parganenus (Fr.) Bond. & Sing. on selected non-basidiomycetous fungi is characterized by rapid necrosis of host cytoplasm. Invagination of the host plasmalemma is followed by the production of a conspicuous extraplasmalemmal wall deposit. Necrosis is the result of disruption of membrane systems and is followed by the penetration of dead host cells. Pathogenesis involves an unidentified toxic substance excreted by the parasite. Contact is not essential.
Asunto(s)
Ascomicetos , Basidiomycota/crecimiento & desarrollo , Polyporaceae/crecimiento & desarrollo , Antibiosis , Ascomicetos/metabolismo , Membrana Celular/metabolismo , Micotoxinas/biosíntesis , Polyporaceae/metabolismo , Polyporaceae/ultraestructuraRESUMEN
The antagonistic activity of Trametes hispida Bagl. in dual culture with Hirschioporus species and other non-basidiomycetous fungi is interpreted as hyphal interference. Hyphae of T. hispida grow into and over colonies of sensitive fungi. Contact with hyphae of T. hispida results in cessation of growth and rapid necrosis of affected cells. Ultrastructural studies of the affected hyphae of Hirschioporus pargamenus (Fr.) Bond. & Sing. showed an early formation of extraplasmalemmal wall deposits, disruption of membrane systems, coagulation of cytoplasm, localized dissolution of walls, and loss of cell contents without penetration by the antagonist.
Asunto(s)
Basidiomycota/crecimiento & desarrollo , Polyporaceae/crecimiento & desarrollo , Ecología , Microscopía Electrónica , Polyporaceae/ultraestructuraRESUMEN
Cytochalasin B inhibited the radial growth rate of Polyporus biennis, and caused an increase in hyphal density through a reduction in the distance between successive branches. Cytochalasin B also produced irregular hyphal profiles and, in a small percentage of hyphae, forked apices. The position of clamp connexions was little affected by cytochalasin B, but the developmental process was specifically inhibited during initiation and during the last two stages, when contact and dissolution of the clamp were occurring. There were no major disruptions of the ultrastructure of the dolipore/parenthesome septum caused by cytochalasin B treatment.