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Jarek Kurnitski - One of the best experts on this subject based on the ideXlab platform.

  • Bioreactivity, Guttation and Agents Influencing Surface Tension of Water Emitted by Actively Growing Indoor Mould Isolates.
    Microorganisms, 2020
    Co-Authors: Maria A. Andersson, László Kredics, Jarek Kurnitski, Johanna Salo, Orsolya Kedves, Irina S. Druzhinina, Heidi Salonen
    Abstract:

    The secretion of metabolites in Guttation droplets by indoor moulds is not well documented. This study demonstrates the Guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and Guttation of liquid droplets detected in young ( 6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (

  • bioreactivity Guttation and agents influencing surface tension of water emitted by actively growing indoor mould isolates
    Microorganisms, 2020
    Co-Authors: Maria A. Andersson, László Kredics, Jarek Kurnitski, Johanna Salo, Orsolya Kedves, Irina S. Druzhinina, Heidi Salonen
    Abstract:

    The secretion of metabolites in Guttation droplets by indoor moulds is not well documented. This study demonstrates the Guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and Guttation of liquid droplets detected in young ( 6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (<3 weeks old) biomasses were toxic more than 10 times towards mammalian cell lines (PK-15 and MNA) compared to the old dormant, dry biomasses, when calculated per biomass wet weight and per conidial particle. Surfactant activity was emitted in exudates from fresh biomass of T. atroviride, Rhizopus sp. and Stachybotrys sp. Surfactant activity was also provoked by fresh conidia from T. atroviride and Stachybotrys sp. strains. Water repealing substances were emitted by cultures of P. expansum, T. atroviride and C. globosum strains. The metabolic state of the indoor fungal growth may influence emission of liquid soluble bioreactive metabolites into the indoor air.

  • Penicillium expansum strain isolated from indoor building material was able to grow on gypsum board and emitted Guttation droplets containing chaetoglobosins and communesins A, B and D.
    Journal of Applied Microbiology, 2019
    Co-Authors: Marja Salo, Tamás Marik, Raimo Mikkola, Maria A. Andersson, László Kredics, Heidi Salonen, Jarek Kurnitski
    Abstract:

    AIMS Emission of toxic metabolites in Guttation droplets of common indoor fungi is not well documented. The aims of this study were (i) to compare mycotoxins in biomass and Guttation droplets from indoor fungi from a building following health complaints among occupants, (ii) to identify the most toxic strain and to test if mycotoxins in Guttation liquids migrated trough air and (iii) to test if toxigenic Penicillium expansum strains grew on gypsum board. METHODS AND RESULTS Biomass suspensions and Guttation droplets from individual fungal colonies representing Aspergillus, Chaetomium, Penicillium, Stachybotrys and Paecilomyces were screened toxic to mammalian cells. The most toxic strain, RcP61 (CBS 145620), was identified as Pen. expansum Link by sequence analysis of the ITS region and a calmodulin gene fragment, and confirmed by the Westerdijk Institute based on ITS and beta-tubulin sequences. The strain was isolated from a cork liner, was able to grow on gypsum board and to produce toxic substances in biomass extracts and Guttation droplets inhibiting proliferation of somatic cells (PK-15, MNA, FL) in up to 20 000-fold dilutions. Toxic compounds in biomass extracts and/or Guttation droplets were determined by HPLC and LC-MS. Strain RcP61 produced communesins A, B and D, and chaetoglobosins in Guttation droplets (the liquid emitted from them) and biomass extracts. The toxins of the Guttation droplets migrated c. 1 cm through air and condensed on a cool surface. CONCLUSIONS The mycotoxin-containing Guttation liquids emitted by Pen. expansum grown on laboratory medium exhibited airborne migration and were >100 times more toxic in bioassays than Guttation droplets produced by indoor isolates of the genera Aspergillus, Chaetomium, Stachybotrys and Paecilomyces. SIGNIFICANCE AND IMPACT OF THE STUDY Toxic exudates produced by Pen. expansum containing communesins A, B and D, and chaetoglobosins were transferable by air. This may represent a novel mechanism of mycotoxin dispersal in indoor environment.

  • Indoor Trichoderma strains emitting peptaibols in Guttation droplets.
    Journal of applied microbiology, 2018
    Co-Authors: Emmanuelle Castagnoli, Tamás Marik, Raimo Mikkola, Maria A. Andersson, László Kredics, Heidi Salonen, Jarek Kurnitski
    Abstract:

    AIMS The production of peptaibols, toxic secondary metabolites of Trichoderma, in the indoor environment is not well-documented. Here, we investigated the toxicity of peptaibols in the Guttation droplets and biomass of Trichoderma strains isolated from problematic buildings. METHODS AND RESULTS Seven indoor-isolated strains of T. atroviride, T. trixiae, T. paraviridescens and T. citrinoviride were cultivated on malt extract agar, gypsum boards and paperboards. Their biomass extracts and Guttation droplets were highly cytotoxic in resting and motile boar sperm cell assays and in inhibition of somatic cell proliferation assays. The toxins were identified with HPLC/ESI-MS/MS as trichorzianines, trilongins, trichostrigocins and trichostrigocin-like peptaibols. They exhibited toxicity profiles similar to the reference peptaibols alamethicin, trilongins, and trichorzianine TA IIIc purified from T. atroviride H1/226. Particular Trichoderma strains emitted the same peptaibols in both their biomasses and exudate droplets. The trilongin-producing T. citrinoviride SJ40 strain grew at 37°C. CONCLUSIONS To our knowledge, this is the first report of indoor-isolated Trichoderma strains producing toxic peptaibols in their Guttation droplets. SIGNIFICANCE AND IMPACT OF THE STUDY This report proves that indoor isolates of Trichoderma release peptaibols in their Guttation droplets. The presence of toxins in these types of exudates may serve as a mechanism of aerosol formation for nonvolatile toxins in the indoor air.

Frederick B Abeles - One of the best experts on this subject based on the ideXlab platform.

  • Xylem sap proteins.
    Plant Physiology, 1991
    Co-Authors: Catherine L Biles, Frederick B Abeles
    Abstract:

    Xylem sap from apple (Malus domestica Borkh), peach (Prunus persica Batsch), and pear (Pyrus communis L.) twigs was collected by means of pressure extrusion. This sap contained a number of acidic peroxidases and other proteins. Two other sources of xylem sap used in this study were stem exudates and Guttation fluid. Similar peroxidases were also found in stem exudates and Guttation fluids of strawberry (Fragaria x ananassa Duch.), tomato (Lycopersicum esculentum L.), and cucumber (Cucumis sativus L.). Isoelectric focusing activity gels showed that two peroxidases (isoelectric point [pl] 9 and pl 4.6) were present in initial stem exudates collected in the first 30 minutes after excision. Subsequent samples of stem exudate collected contained only the pl 4.6 isozyme. The pl 4.6 peroxidase isozyme was also found in root tissue and Guttation fluid. These observations suggest that roots produce and secrete the pl 4.6 peroxidase into xylem sap. Cucumber seedlings were treated with 100 microliters per liter ethylene for 16 hours and the exudate from decapitated hypocotyl stumps was collected over a 3 hour period. Ethylene increased the peroxidase activity of stem exudates and inhibited the amount of exudate released. These observations suggest that xylem sap peroxidase may play a role in plugging damaged vascular tissue.

  • Xylem sap proteins.
    Plant Physiology, 1991
    Co-Authors: Catherine L Biles, Frederick B Abeles
    Abstract:

    Xylem sap from apple (Malus domestica Borkh), peach (Prunus persica Batsch), and pear (Pyrus communis L.) twigs was collected by means of pressure extrusion. This sap contained a number of acidic peroxidases and other proteins. Two other sources of xylem sap used in this study were stem exudates and Guttation fluid. Similar peroxidases were also found in stem exudates and Guttation fluids of strawberry (Fragaria x ananassa Duch.), tomato (Lycopersicum esculentum L.), and cucumber (Cucumis sativus L.). Isoelectric focusing activity gels showed that two peroxidases (isoelectric point [pl] 9 and pl 4.6) were present in initial stem exudates collected in the first 30 minutes after excision. Subsequent samples of stem exudate collected contained only the pl 4.6 isozyme. The pl 4.6 peroxidase isozyme was also found in root tissue and Guttation fluid. These observations suggest that roots produce and secrete the pl 4.6 peroxidase into xylem sap. Cucumber seedlings were treated with 100 microliters per liter ethylene for 16 hours and the exudate from decapitated hypocotyl stumps was collected over a 3 hour period. Ethylene increased the peroxidase activity of stem exudates and inhibited the amount of exudate released. These observations suggest that xylem sap peroxidase may play a role in plugging damaged vascular tissue.

Klaus Kloppstech - One of the best experts on this subject based on the ideXlab platform.

  • identification of Guttation fluid proteins the presence of pathogenesis related proteins in non infected barley plants
    Physiologia Plantarum, 2003
    Co-Authors: Ingo Grunwald, Ines Rupprecht, Gadi Schuster, Klaus Kloppstech
    Abstract:

    The main driving force behind water transport in plants is the air's low water potential. In the presence of high humidity, the transpiration process is halted and water transport is mainly sustained by the root pressure. The surplus of water following the removal of essential components (e.g. salts) is excreted by the plant via Guttation through the hydathodes. When Guttation occurs, the plant surface is wetted. These are the conditions that will allow epiphytic living, motile bacteria to move and to eventually enter the plant's interior via the hydathodes. The question arose as to whether the plant has developed a protection mechanism against motile bacteria in the vicinity of the hydathodes. Such a protection mechanism could use the well known pathogenesis-related (PR) proteins. Indeed, an analysis of the Guttation fluid using one- and two-dimensional electrophoresis showed a clustering of approximately 200 proteins, primarily with isoelectric points in the acidic pH. Proteins identified using electrospray ionization mass spectroscopic analysis and western blot analysis belong mostly to the family of PR-proteins suggesting a role in plant protection against invaders. The protein profile of the Guttation fluid was remarkably modified by treating plants with methyl jasmonic acid suggesting that the protein composition of the Guttation fluid is controlled by internal and/or external stimuli.

  • Identification of Guttation fluid proteins: the presence of pathogenesis‐related proteins in non‐infected barley plants
    Physiologia Plantarum, 2003
    Co-Authors: Ingo Grunwald, Ines Rupprecht, Gadi Schuster, Klaus Kloppstech
    Abstract:

    The main driving force behind water transport in plants is the air's low water potential. In the presence of high humidity, the transpiration process is halted and water transport is mainly sustained by the root pressure. The surplus of water following the removal of essential components (e.g. salts) is excreted by the plant via Guttation through the hydathodes. When Guttation occurs, the plant surface is wetted. These are the conditions that will allow epiphytic living, motile bacteria to move and to eventually enter the plant's interior via the hydathodes. The question arose as to whether the plant has developed a protection mechanism against motile bacteria in the vicinity of the hydathodes. Such a protection mechanism could use the well known pathogenesis-related (PR) proteins. Indeed, an analysis of the Guttation fluid using one- and two-dimensional electrophoresis showed a clustering of approximately 200 proteins, primarily with isoelectric points in the acidic pH. Proteins identified using electrospray ionization mass spectroscopic analysis and western blot analysis belong mostly to the family of PR-proteins suggesting a role in plant protection against invaders. The protein profile of the Guttation fluid was remarkably modified by treating plants with methyl jasmonic acid suggesting that the protein composition of the Guttation fluid is controlled by internal and/or external stimuli.

Catherine L Biles - One of the best experts on this subject based on the ideXlab platform.

  • Xylem sap proteins.
    Plant Physiology, 1991
    Co-Authors: Catherine L Biles, Frederick B Abeles
    Abstract:

    Xylem sap from apple (Malus domestica Borkh), peach (Prunus persica Batsch), and pear (Pyrus communis L.) twigs was collected by means of pressure extrusion. This sap contained a number of acidic peroxidases and other proteins. Two other sources of xylem sap used in this study were stem exudates and Guttation fluid. Similar peroxidases were also found in stem exudates and Guttation fluids of strawberry (Fragaria x ananassa Duch.), tomato (Lycopersicum esculentum L.), and cucumber (Cucumis sativus L.). Isoelectric focusing activity gels showed that two peroxidases (isoelectric point [pl] 9 and pl 4.6) were present in initial stem exudates collected in the first 30 minutes after excision. Subsequent samples of stem exudate collected contained only the pl 4.6 isozyme. The pl 4.6 peroxidase isozyme was also found in root tissue and Guttation fluid. These observations suggest that roots produce and secrete the pl 4.6 peroxidase into xylem sap. Cucumber seedlings were treated with 100 microliters per liter ethylene for 16 hours and the exudate from decapitated hypocotyl stumps was collected over a 3 hour period. Ethylene increased the peroxidase activity of stem exudates and inhibited the amount of exudate released. These observations suggest that xylem sap peroxidase may play a role in plugging damaged vascular tissue.

  • Xylem sap proteins.
    Plant Physiology, 1991
    Co-Authors: Catherine L Biles, Frederick B Abeles
    Abstract:

    Xylem sap from apple (Malus domestica Borkh), peach (Prunus persica Batsch), and pear (Pyrus communis L.) twigs was collected by means of pressure extrusion. This sap contained a number of acidic peroxidases and other proteins. Two other sources of xylem sap used in this study were stem exudates and Guttation fluid. Similar peroxidases were also found in stem exudates and Guttation fluids of strawberry (Fragaria x ananassa Duch.), tomato (Lycopersicum esculentum L.), and cucumber (Cucumis sativus L.). Isoelectric focusing activity gels showed that two peroxidases (isoelectric point [pl] 9 and pl 4.6) were present in initial stem exudates collected in the first 30 minutes after excision. Subsequent samples of stem exudate collected contained only the pl 4.6 isozyme. The pl 4.6 peroxidase isozyme was also found in root tissue and Guttation fluid. These observations suggest that roots produce and secrete the pl 4.6 peroxidase into xylem sap. Cucumber seedlings were treated with 100 microliters per liter ethylene for 16 hours and the exudate from decapitated hypocotyl stumps was collected over a 3 hour period. Ethylene increased the peroxidase activity of stem exudates and inhibited the amount of exudate released. These observations suggest that xylem sap peroxidase may play a role in plugging damaged vascular tissue.

László Kredics - One of the best experts on this subject based on the ideXlab platform.

  • Bioreactivity, Guttation and Agents Influencing Surface Tension of Water Emitted by Actively Growing Indoor Mould Isolates.
    Microorganisms, 2020
    Co-Authors: Maria A. Andersson, László Kredics, Jarek Kurnitski, Johanna Salo, Orsolya Kedves, Irina S. Druzhinina, Heidi Salonen
    Abstract:

    The secretion of metabolites in Guttation droplets by indoor moulds is not well documented. This study demonstrates the Guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and Guttation of liquid droplets detected in young ( 6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (

  • bioreactivity Guttation and agents influencing surface tension of water emitted by actively growing indoor mould isolates
    Microorganisms, 2020
    Co-Authors: Maria A. Andersson, László Kredics, Jarek Kurnitski, Johanna Salo, Orsolya Kedves, Irina S. Druzhinina, Heidi Salonen
    Abstract:

    The secretion of metabolites in Guttation droplets by indoor moulds is not well documented. This study demonstrates the Guttation of metabolites by actively growing common indoor moulds. Old and fresh biomasses of indoor isolates of Aspergillus versicolor, Chaetomium globosum, Penicillium expansum, Trichoderma atroviride, T. trixiae, Rhizopus sp. and Stachybotrys sp. were compared. Metabolic activity indicated by viability staining and Guttation of liquid droplets detected in young ( 6 months old) cultures consisting of dehydrated hyphae and dormant conidia. Fresh (<3 weeks old) biomasses were toxic more than 10 times towards mammalian cell lines (PK-15 and MNA) compared to the old dormant, dry biomasses, when calculated per biomass wet weight and per conidial particle. Surfactant activity was emitted in exudates from fresh biomass of T. atroviride, Rhizopus sp. and Stachybotrys sp. Surfactant activity was also provoked by fresh conidia from T. atroviride and Stachybotrys sp. strains. Water repealing substances were emitted by cultures of P. expansum, T. atroviride and C. globosum strains. The metabolic state of the indoor fungal growth may influence emission of liquid soluble bioreactive metabolites into the indoor air.

  • Penicillium expansum strain isolated from indoor building material was able to grow on gypsum board and emitted Guttation droplets containing chaetoglobosins and communesins A, B and D.
    Journal of Applied Microbiology, 2019
    Co-Authors: Marja Salo, Tamás Marik, Raimo Mikkola, Maria A. Andersson, László Kredics, Heidi Salonen, Jarek Kurnitski
    Abstract:

    AIMS Emission of toxic metabolites in Guttation droplets of common indoor fungi is not well documented. The aims of this study were (i) to compare mycotoxins in biomass and Guttation droplets from indoor fungi from a building following health complaints among occupants, (ii) to identify the most toxic strain and to test if mycotoxins in Guttation liquids migrated trough air and (iii) to test if toxigenic Penicillium expansum strains grew on gypsum board. METHODS AND RESULTS Biomass suspensions and Guttation droplets from individual fungal colonies representing Aspergillus, Chaetomium, Penicillium, Stachybotrys and Paecilomyces were screened toxic to mammalian cells. The most toxic strain, RcP61 (CBS 145620), was identified as Pen. expansum Link by sequence analysis of the ITS region and a calmodulin gene fragment, and confirmed by the Westerdijk Institute based on ITS and beta-tubulin sequences. The strain was isolated from a cork liner, was able to grow on gypsum board and to produce toxic substances in biomass extracts and Guttation droplets inhibiting proliferation of somatic cells (PK-15, MNA, FL) in up to 20 000-fold dilutions. Toxic compounds in biomass extracts and/or Guttation droplets were determined by HPLC and LC-MS. Strain RcP61 produced communesins A, B and D, and chaetoglobosins in Guttation droplets (the liquid emitted from them) and biomass extracts. The toxins of the Guttation droplets migrated c. 1 cm through air and condensed on a cool surface. CONCLUSIONS The mycotoxin-containing Guttation liquids emitted by Pen. expansum grown on laboratory medium exhibited airborne migration and were >100 times more toxic in bioassays than Guttation droplets produced by indoor isolates of the genera Aspergillus, Chaetomium, Stachybotrys and Paecilomyces. SIGNIFICANCE AND IMPACT OF THE STUDY Toxic exudates produced by Pen. expansum containing communesins A, B and D, and chaetoglobosins were transferable by air. This may represent a novel mechanism of mycotoxin dispersal in indoor environment.

  • Indoor Trichoderma strains emitting peptaibols in Guttation droplets.
    Journal of applied microbiology, 2018
    Co-Authors: Emmanuelle Castagnoli, Tamás Marik, Raimo Mikkola, Maria A. Andersson, László Kredics, Heidi Salonen, Jarek Kurnitski
    Abstract:

    AIMS The production of peptaibols, toxic secondary metabolites of Trichoderma, in the indoor environment is not well-documented. Here, we investigated the toxicity of peptaibols in the Guttation droplets and biomass of Trichoderma strains isolated from problematic buildings. METHODS AND RESULTS Seven indoor-isolated strains of T. atroviride, T. trixiae, T. paraviridescens and T. citrinoviride were cultivated on malt extract agar, gypsum boards and paperboards. Their biomass extracts and Guttation droplets were highly cytotoxic in resting and motile boar sperm cell assays and in inhibition of somatic cell proliferation assays. The toxins were identified with HPLC/ESI-MS/MS as trichorzianines, trilongins, trichostrigocins and trichostrigocin-like peptaibols. They exhibited toxicity profiles similar to the reference peptaibols alamethicin, trilongins, and trichorzianine TA IIIc purified from T. atroviride H1/226. Particular Trichoderma strains emitted the same peptaibols in both their biomasses and exudate droplets. The trilongin-producing T. citrinoviride SJ40 strain grew at 37°C. CONCLUSIONS To our knowledge, this is the first report of indoor-isolated Trichoderma strains producing toxic peptaibols in their Guttation droplets. SIGNIFICANCE AND IMPACT OF THE STUDY This report proves that indoor isolates of Trichoderma release peptaibols in their Guttation droplets. The presence of toxins in these types of exudates may serve as a mechanism of aerosol formation for nonvolatile toxins in the indoor air.