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Endogenous polyamine content of the ectomycorrhizal fungus Paxillus involutus, as well as the activity of its biosynthetic enzymes in relation to mycelia ageing were investigated in this work. Polyamines in free, PCA-soluble and insoluble conjugated forms, are present in Paxillus involutus mycelia in relatively high amounts and the ratio of putrescine to spermidine is age-dependent. Both arginine- and ornithine-decarboxylases are present, but putrescine biosynthesis proceeds mostly via ornithine decarboxylase and decreases with the age of mycelia. There was a large release of free polyamines from mycelia which showed age-dependent features. Clear polyamine uptake was observed in 2-wk-old mycelia and no competition between putrescine and cadaverine was detected. Putrescine uptake seems to reduce ornithine decarboxylase activity, but does not affect arginine decarboxylase.
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http://dx.doi.org/10.1046/j.1469-8137.1999.00480.x | DOI Listing |
Environ Microbiol
August 2025
Polish Academy of Sciences, Institute of Bioorganic Chemistry, Poznań, Poland.
This metabolomic study investigates, using GC MS/MS analysis, the molecular response of Paxillus involutus mycelia to prolonged low temperature (4°C) exposure. Alongside reduced growth, decreased overall nutrient levels, and increased oxidative stress indicators, analyses revealed a significant increase in nitrogen (N) concentration and enhanced N metabolism, particularly via the GS-GOGAT pathway, which was associated with elevated concentrations of numerous amino acids. In contrast, carbon (C) metabolism was not intensified but largely reprogrammed, with varying changes in carbohydrate abundance but higher levels of several stress-related metabolites, such as trehalose and inositol family members, indicating activation of tolerance mechanisms, all with unchanged C (%).
View Article and Find Full Text PDFFungal Biol
December 2024
Natural History Museum, Cromwell Road, SW7 5BD, London, UK.
Phyllosilicates provide a primary source of minerals used by microorganisms and plants, particularly clay minerals, i.e., phyllosilicates of very small particle size.
View Article and Find Full Text PDFBMC Plant Biol
October 2024
Escola Superior de Biotecnologia, Catholic University of Portugal, Rua Diogo Botelho, 1327, Porto, 4169-005, Portugal.
Drug Chem Toxicol
May 2025
Institute for the Application of Nuclear Energy (INEP), University of Belgrade, Zemun, Serbia.
In the present study, phenolic and flavonoid composition and biological properties of methanolic extract of wild growing collected in Serbia have been investigated. Ellagic acid was the most abundant phenolic compound (34.92 µg g-), followed by 5-O-caffeoylquinic acid (4.
View Article and Find Full Text PDFPlant Physiol Biochem
October 2024
GreenUPorto - Sustainable Agrifood Production Research Centre/Inov4Agro, Department of Biology, Faculty of Sciences, University of Porto, Campus Campo Alegre, Rua do Campo Alegre s/n, 4169-007, Porto, Portugal.
Castanea sativa Miller, a high-valuable crop for Mediterranean countries, is facing frequent and prolonged periods of heat and drought, severely affecting chestnut production. Aiming to tackle this problem, this study unraveled the influence of mycorrhizal association with the fungi Paxillus involutus (Batsch) on young chestnut plants' responses to combined heat (42 °C; 4 h/day) and drought (no irrigation until soil moisture reached 25%) over 21 days of stress exposure. Heat stress had no harmful effects on growth, photosynthesis, nor induced oxidative stress in either mycorrhizal (MR) or non-mycorrhizal (NMR) chestnut plants.
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