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Ralf G Berger - One of the best experts on this subject based on the ideXlab platform.
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formation of decatrienones with a pineapple like aroma from 1 13c acetate by cell cultures of the birch polypore fomitopsis betulina
Journal of Agricultural and Food Chemistry, 2020Co-Authors: Miriam Grosse, Ulrich Krings, Ralf G BergerAbstract:During submerged cultivation, the edible basidiomycete Fomitopsis betulina (previously Piptoporus betulinus) developed a fruity odor, strongly reminding of pineapple. Olfactometric analysis showed that this impression was mainly caused by the two (5E/Z,7E,9)-decatrien-2-ones. At the time of maximum concentration on the 5th day, the (5E/5Z)-ratio was 94:6. Three hypotheses were experimentally examined to shed light onto the genesis of the uncommon volatiles: first, an indirect effect of agro-industrial side-streams, such as cabbage cuttings, supporting good growth; second, an unsaturated odd-numbered fatty acid precursor; and third, a polyketide-like pathway. In the presence of 1-13C- or 2-13C-acetate up to five acetates were incorporated into the molecular ions of the C10-body. Addition of 1-13C-pyruvate or 1-13C-lactate did not confirm an odd-numbered starter of the polyketide chain. None of the methylketones was found in pineapple or any other food before.
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psop1 a milk clotting aspartic peptidase from the basidiomycete fungus Piptoporus soloniensis
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Hassan Abd Elbaky, Diana Linke, Manfred Nimtz, Ralf G BergerAbstract:The first enzyme of the basidiomycete Piptoporus soloniensis, a peptidase (PsoP1), was characterized after isolation from submerged cultures, purification by fractional precipitation, and preparati...
Petr Baldrian - One of the best experts on this subject based on the ideXlab platform.
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Extracellular Enzymes of the White-Rot Fungus Fomes fomentarius and Purification of 1,4-β-Glucosidase
Applied Biochemistry and Biotechnology, 2012Co-Authors: Tomáš Větrovský, Petr Baldrian, Jiří GabrielAbstract:Production of the lignocellulose-degrading enzymes endo-1,4-β-glucanase, 1,4-β-glucosidase, cellobiohydrolase, endo-1,4-β-xylanase, 1,4-β-xylosidase, Mn peroxidase, and laccase was characterized in a common wood-rotting fungus Fomes fomentarius, a species able to efficiently decompose dead wood, and compared to the production in eight other fungal species. The main aim of this study was to characterize the 1,4-β-glucosidase produced by F. fomentarius that was produced in high quantities in liquid stationary culture (25.9 U ml−1), at least threefold compared to other saprotrophic basidiomycetes, such as Rhodocollybia butyracea, Hypholoma fasciculare, Irpex lacteus, Fomitopsis pinicola, Pleurotus ostreatus, Piptoporus betulinus, and Gymnopus sp. (between 0.7 and 7.9 U ml−1). The 1,4-β-glucosidase enzyme was purified to electrophoretic homogeneity by both anion-exchange and size-exclusion chromatography. A single 1,4-β-glucosidase was found to have an apparent molecular mass of 58 kDa and a pI of 6.7. The enzyme exhibited high thermotolerance with an optimum temperature of 60 °C. Maximal activity was found in the pH range of 4.5–5.0, and KM and Vmax values were 62 μM and 15.8 μmol min−1 l−1, respectively, when p-nitrophenylglucoside was used as a substrate. The enzyme was competitively inhibited by glucose with a Ki of 3.37 mM. The enzyme also acted on p-nitrophenylxyloside, p-nitrophenylcellobioside, p-nitrophenylgalactoside, and p-nitrophenylmannoside with optimal pH values of 6.0, 3.5, 5.0, and 4.0–6.0, respectively. The combination of relatively low molecular mass and low KM value make the 1,4-β-glucosidase a promising enzyme for biotechnological applications.
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degradation of cellulose and hemicelluloses by the brown rot fungus Piptoporus betulinus production of extracellular enzymes and characterization of the major cellulases
Microbiology, 2006Co-Authors: Vendula Valášková, Petr BaldrianAbstract:Piptoporus betulinus is a common wood-rotting fungus parasitic for birch (Betula species). It is able to cause fast mass loss of birch wood or other lignocellulose substrates. When grown on wheat straw, P. betulinus caused 65 % loss of dry mass within 98 days, and it produced endo-1,4-β-glucanase (EG), endo-1,4-β-xylanase, endo-1,4-β-mannanase, 1,4-β-glucosidase (BG), 1,4-β-xylosidase, 1,4-β-mannosidase and cellobiohydrolase activities. The fungus was not able to efficiently degrade crystalline cellulose. The major glycosyl hydrolases, endoglucanase EG1 and β-glucosidase BG1, were purified. EG1 was a protein of 62 kDa with a pI of 2.6–2.8. It cleaved cellulose internally, produced cellobiose and glucose from cellulose and cellooligosaccharides, and also showed β-xylosidase and endoxylanase activities. The K m for carboxymethylcellulose was 3.5 g l−1, with the highest activity at pH 3.5 and 70 °C. BG1 was a protein of 36 kDa with a pI around 2.6. It was able to produce glucose from cellobiose and cellooligosaccharides, but also produced galactose, mannose and xylose from the respective oligosaccharides and showed some cellobiohydrolase activity. The K m for p-nitrophenyl-1,4-β-glucoside was 1.8 mM, with the highest activity at pH 4 and 60 °C, and the enzyme was competitively inhibited by glucose (K i=5.8 mM). The fungus produced mainly β-glucosidase and β-mannosidase activity in its fruit bodies, while higher activities of endoglucanase, endoxylanase and β-xylosidase were found in fungus-colonized wood.
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Estimation of bound and free fractions of lignocellulose-degrading enzymes of wood-rotting fungi Pleurotus ostreatus, Trametes versicolor and Piptoporus betulinus.
Research in microbiology, 2005Co-Authors: Vendula Valášková, Petr BaldrianAbstract:Liquid cultures with cellulose and solid state fermentation cultures on wheat straw of the white-rot fungi Pleurotus ostreatus and Trametes versicolor and the brown-rot fungus Piptoporus betulinus were assayed for the free and solid fraction-bound activity of lignocellulose-degrading enzymes. The majority of the ligninolytic enzymes laccase and Mn peroxidase was detected in the free fraction of P. ostreatus and T. versicolor. The endocleaving enzymes endo-1,4-beta-glucanase, endo-1,4-beta-mannanase and endo-1,4-beta-xylanase were detected almost exclusively in the free fraction, while significant amounts of 1,4-beta-glucosidase, cellobiohydrolase, 1,4-beta-xylosidase and 1,4-beta-mannosidase were present in the bound fraction depending on the mode of cultivation and the species. The bound enzymes accounted for 66% of the total activity in P. ostreatus straw cultures, 35% in T. versicolor and only 8% in P. betulinus. The enzymes also showed significant differences in freeze-drying stability. Hydrolases in general showed high stability, whereas laccase and Mn peroxidase of P. ostreatus were the least stable.
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Intraspecific variability in growth response to cadmium of the wood-rotting fungus Piptoporus betulinus.
Mycologia, 2002Co-Authors: Petr Baldrian, Jiří GabrielAbstract:The intraspecific variability in growth response to cadmium (Cd) on agar media and in liquid culture was studied among fourteen strains of a wood-rotting fungus Piptoporus betulinus. The variabilit...
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heavy and trace metals in wood inhabiting fungi fomitopsis pinicola ganoderma applanatum Piptoporus betulinus and stereum hirsutum from medium polluted sites in czech republic
Toxicological & Environmental Chemistry, 1999Co-Authors: Petr Baldrian, J Gabriel, E Curdova, M Suchanek, Petr RychlovskýAbstract:Contents of Ag, Al, As, Cd, Cr, Cu, Mo, Ni, Pb, Se, Tl, and Zn in fruiting bodies of wood‐inhabiting fungi Fomitopsis pinicola, Piptoporus betulinus, Stereum hirsutum, and Ganoderma applanatum collected on 13 sites with medium level of air pollution were estimated. Concentrations of individual metals (ppm) ranged from 0.0135 to 1.1165(Ag), 15.9 to 1443.1 (Al), 0.0665 to 0.7345 (As), 0.039 to 3.832 (Cd), 0.49 to 5.10 (Cr), 1.13 to 49.9 (Cu), 0.009 to 0.9995 (Mo), 0.4375 to 6.058 (Ni), 0.112 to 16.9 (Pb), 0.011 to 0.126 (Se), 0.0017 to 0.0261 (Tl), and from 15 to 1823 (Zn). The studied species of fungi were divided into groups according to the patterns of accumulation of respective metals. Wood‐inhabiting fungi were found to accumulate lower levels of Ag, As, Cd, Cu, Pb, and Se than fungi growing in soil. In studied species, little interspecific variability in contents of Cd, Cu, Pb, and Zn was found.
Jiří Gabriel - One of the best experts on this subject based on the ideXlab platform.
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Extracellular Enzymes of the White-Rot Fungus Fomes fomentarius and Purification of 1,4-β-Glucosidase
Applied Biochemistry and Biotechnology, 2012Co-Authors: Tomáš Větrovský, Petr Baldrian, Jiří GabrielAbstract:Production of the lignocellulose-degrading enzymes endo-1,4-β-glucanase, 1,4-β-glucosidase, cellobiohydrolase, endo-1,4-β-xylanase, 1,4-β-xylosidase, Mn peroxidase, and laccase was characterized in a common wood-rotting fungus Fomes fomentarius, a species able to efficiently decompose dead wood, and compared to the production in eight other fungal species. The main aim of this study was to characterize the 1,4-β-glucosidase produced by F. fomentarius that was produced in high quantities in liquid stationary culture (25.9 U ml−1), at least threefold compared to other saprotrophic basidiomycetes, such as Rhodocollybia butyracea, Hypholoma fasciculare, Irpex lacteus, Fomitopsis pinicola, Pleurotus ostreatus, Piptoporus betulinus, and Gymnopus sp. (between 0.7 and 7.9 U ml−1). The 1,4-β-glucosidase enzyme was purified to electrophoretic homogeneity by both anion-exchange and size-exclusion chromatography. A single 1,4-β-glucosidase was found to have an apparent molecular mass of 58 kDa and a pI of 6.7. The enzyme exhibited high thermotolerance with an optimum temperature of 60 °C. Maximal activity was found in the pH range of 4.5–5.0, and KM and Vmax values were 62 μM and 15.8 μmol min−1 l−1, respectively, when p-nitrophenylglucoside was used as a substrate. The enzyme was competitively inhibited by glucose with a Ki of 3.37 mM. The enzyme also acted on p-nitrophenylxyloside, p-nitrophenylcellobioside, p-nitrophenylgalactoside, and p-nitrophenylmannoside with optimal pH values of 6.0, 3.5, 5.0, and 4.0–6.0, respectively. The combination of relatively low molecular mass and low KM value make the 1,4-β-glucosidase a promising enzyme for biotechnological applications.
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enhancement of autofluorescence of the brown rot fungus Piptoporus betulinus by metal ions
Folia Microbiologica, 2010Co-Authors: Zdeněk žižka, T Vetrovský, Jiří GabrielAbstract:The autofluorescence (primary fluorescence, AF) of agar cultures of the brown-rot fungus Piptoporus betulinus was investigated in Zeiss Jenalumar and Nikon Eclipse 8201 fluorescence microscopes at various excitations. The strongest AF of hyphae was found in minimal medium with glucose, where the hyphae exhibited green AF at violet (450 nm) excitation and red AF at green (570 nm) excitation. Addition of metals to cultivation media led to enhanced white-blue AF in the presence of Co (at 450 nm) and yellow to yellow-brown AF at 510 nm. When cultivated with Mn and Zn, enhanced AF of intracellular content was observed. Only a weak signal was found in the presence of Cu and Fe.
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Intraspecific variability in growth response to cadmium of the wood-rotting fungus Piptoporus betulinus.
Mycologia, 2002Co-Authors: Petr Baldrian, Jiří GabrielAbstract:The intraspecific variability in growth response to cadmium (Cd) on agar media and in liquid culture was studied among fourteen strains of a wood-rotting fungus Piptoporus betulinus. The variabilit...
Lynne Boddy - One of the best experts on this subject based on the ideXlab platform.
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the rare oak polypore Piptoporus quercinus population structure spore germination and growth
Fungal Ecology, 2010Co-Authors: Martha E Crockatt, Alice Campbell, Leanne Allum, Martyn A Ainsworth, Lynne BoddyAbstract:Piptoporus quercinus, the rare oak polypore, is one of only four non-lichenised fungi listed on Schedule 8 of the Wildlife and Countryside Act 1981, in the UK. It is thereby accorded the highest level of legal protection in the UK. It fruits exclusively on oak (Quercus spp.), primarily veteran trees in old growth wood pasture and parkland in the midlands and southern England. Beyond information on fruit body occurrence, little is known of the ecology of this species. Germination of chlamydospores and basidiospores was investigated under a range of conditions (temperature, pH, different media). The mating system was ascertained by pairing single spore derived isolates, and somatic compatibility investigated by pairing fruit body isolates. Germination of basidiospores was consistently below 1 % with most success occurring on 2 % malt extract agar adjusted to pH 4 at 20 °C. Chlamydospores had a much higher average percentage of germination (47 % ± 22), and germinated even after prolonged exposure to extreme conditions (desiccation or exposure to −20 °C or 40 °C for 48 h, 7 d or 14 d). The mating system was unifactorial (bipolar), although only four mating alleles were discovered in the six populations sampled, two alleles being unique to one fruit body. There were no signs of somatic incompatibility between the majority of isolates, exceptions being an isolate from Wentwood, South Wales, and an isolate from Germany collected in 1975, both of which displayed apparent signs of somatic incompatibility in all experimental pairings. The lack of somatic incompatibility between the majority of UK isolates, together with the low number of mating alleles, may point to inbreeding within the UK population. Apparently compatible isolates were not, however, clonal, as shown by variation in their mycelial extension rates on agar at various temperatures.
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growth and interspecific interactions of the rare oak polypore Piptoporus quercinus
Fungal Biology, 2004Co-Authors: Paul Wald, Martha E Crockatt, Victoria Gray, Lynne BoddyAbstract:Growth and interactions of Piptoporus quercinus were studied in artificial culture to give insights into the ecological characteristics of a species which is both rare and widespread. P. quercinus grew slowly under all conditions, the maximum ranging between 1.9 and 3.15 mm d −1 , depending on isolate, at 25°C pH 3.75. Upper limits for growth were 25–30° or above 30°, depending on isolate, and pH 6.6. Lower limits for growth were 5–10°, between -1.75 and -2.5 MPa; there was still growth at pH 1.81. Preincubating plates at 5° for 77 d and then incubating at 20° resulted in a significantly greater extension rate (2.89 mm d −1 ) than when incubated continuously at 20° (1.70 mm d −1 ) for one isolate though not for another isolate. P. quercinus survived exposure to low temperature (−18° for 7 d), showing renewed growth, albeit limited, after a lag of 37 d. It was a poor combatant, being unable to replace any of the eight fungi (with a range of ecological roles) against which it was paired, and being replaced or partially replaced by most, on 2% MA at pH 5.49, at pH 3.75 and at -1.25 MPa. It did, however, inhibit extension rate of some other heart rot fungi. Results are discussed in an ecological context.
Hassan Abd Elbaky - One of the best experts on this subject based on the ideXlab platform.
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psop1 a milk clotting aspartic peptidase from the basidiomycete fungus Piptoporus soloniensis
Journal of Agricultural and Food Chemistry, 2011Co-Authors: Hassan Abd Elbaky, Diana Linke, Manfred Nimtz, Ralf G BergerAbstract:The first enzyme of the basidiomycete Piptoporus soloniensis, a peptidase (PsoP1), was characterized after isolation from submerged cultures, purification by fractional precipitation, and preparati...