Effects of polysaccharides (FI0-b) from mycelium of Ganoderma tsugae on proinflammatory cytokine production by THP-1 cells and human PBMC (I). (1/385)

AIM: To compare the effects of water-soluble polysaccharides, FI0-b, and its formic acid-modified derivative, FI0-b-H, on production of human proinflammatory cytokines. METHODS: The polysaccharides were modified by formic acid. Cytokine production was quantitated by radioimmunoassay. mRNA for cytokines was measured by semi-quantitative RT-PCR. RESULTS: FI0-b and FI0-b-H 4, 40, and 400 mg/L significantly downregulated interleukin-1 alpha (IL-1 alpha) production by THP-1 cells induced by lypopolysaccharide (LPS) 1 or 10 mg/L and phorbol myristate acetate (PMA) 200 nmol/L. At lower stimulation with LPS 10 mg/L and PMA 200 nmol/L, both polysaccharides significantly upregulated tumor necrosis factor alpha (TNF alpha) production by THP-1 cells. However, at higher stimulation with LPS 100 mg/L and PMA 200 nmol/L, they downregulated TNF alpha production. FI0-b-H downregulated interleukin-8 (IL-8) production by THP-1 cells at a lower-dose of LPS 1 mg/L and PMA 200 nmol/L, but upregulated IL-8 production at a higher-dose of LPS 10 mg/L and PMA 200 nmol/L. Production of cytokines (IL-1 alpha and TNF alpha) was transcriptionally or post-transcriptionally regulated by FI0-b and FI0-b-H. CONCLUSION: The water-soluble polysaccharides of Ganoderma tsugae mycelium have bidirectional immunomodulatory effects on cytokine production in different stimulatory conditions in a dose-dependent manner. Compared with FI0-b, FI0-b-H has more marked effects on human proinflammatory cytokine production.  (+info)

Effects of polysaccharides (FI0-c) from mycelium of Ganoderma tsugae on proinflammatory cytokine production by THP-1 cells and human PBMC (II). (2/385)

AIM: To study the effects of water-soluble polysaccharides. FI0-c, and its sulfated derivative, FI0-c-S, on production of human proinflammatory cytokines, interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor alpha (TNF alpha). METHODS: The herbal polysaccharides were modified by chlorosulfornic acid in dimethyl sulfoxide (Me2SO). Cytokine production was measured by radioimmunoassay, mRNA for the cytokines was measured by semi-quantitative RT-PCR. RESULTS: FI0-c 4 mg/L itself induced IL-1 alpha production by THP-1 cells without stimulants, such as lipopolysaccharides (LPS) and phorbol myristate acetate (PMA). On the other hand, FI0-c and FI0-c-S inhibited the IL-1 alpha production by THP-1 cells with these stimulants. FI0-c and FI0-c-S significantly upregulated TNF alpha production by THP-1 cells without stimulants or at a low dose of LPS 10 mg/L and PMA 200 nmol/L, whereas these polysaccharides markedly downregulated the TNF alpha production by a high dose of LPS 100 mg/L and PMA. Human peripheral blood mononuclear cells (PBMC) responded to FI0-c and FI0-c-S in IL-1 alpha and TNF alpha production in a fashion similar to THP-1 cell responses. FI0-c 4 mg/L downregulated high-dose LPS- and PMA-induced IL-1 alpha or TNF alpha mRNA and their protein production by THP-1 cells. CONCLUSION: The water-soluble polysaccharides of Ganoderma tsugae mycelium have bidirectional immunomodulatory effects on cytokine production in different cell stimulatory conditions. Chemical modification of this polysaccharide changed the intensity of regulatory effect on cytokine production.  (+info)

A phosphate transporter gene from the extra-radical mycelium of an arbuscular mycorrhizal fungus Glomus intraradices is regulated in response to phosphate in the environment. (3/385)

The majority of vascular flowering plants are able to form symbiotic associations with arbuscular mycorrhizal fungi. These symbioses, termed arbuscular mycorrhizas, are mutually beneficial, and the fungus delivers phosphate to the plant while receiving carbon. In these symbioses, phosphate uptake by the arbuscular mycorrhizal fungus is the first step in the process of phosphate transport to the plant. Previously, we cloned a phosphate transporter gene involved in this process. Here, we analyze the expression and regulation of a phosphate transporter gene (GiPT) in the extra-radical mycelium of the arbuscular mycorrhizal fungus Glomus intraradices during mycorrhizal association with carrot or Medicago truncatula roots. These analyses reveal that GiPT expression is regulated in response to phosphate concentrations in the environment surrounding the extra-radical hyphae and modulated by the overall phosphate status of the mycorrhiza. Phosphate concentrations, typical of those found in the soil solution, result in expression of GiPT. These data imply that G. intraradices can perceive phosphate levels in the external environment but also suggest the presence of an internal phosphate sensing mechanism.  (+info)

Translocation and utilization of fungal storage lipid in the arbuscular mycorrhizal symbiosis. (4/385)

The arbuscular mycorrhizal (AM) symbiosis is responsible for huge fluxes of photosynthetically fixed carbon from plants to the soil. Carbon is transferred from the plant to the fungus as hexose, but the main form of carbon stored by the mycobiont at all stages of its life cycle is triacylglycerol. Previous isotopic labeling experiments showed that the fungus exports this storage lipid from the intraradical mycelium (IRM) to the extraradical mycelium (ERM). Here, in vivo multiphoton microscopy was used to observe the movement of lipid bodies through the fungal colony and to determine their sizes, distribution, and velocities. The distribution of lipid bodies along fungal hyphae suggests that they are progressively consumed as they move toward growing tips. We report the isolation and measurements of expression of an AM fungal expressed sequence tag that encodes a putative acyl-coenzyme A dehydrogenase; its deduced amino acid sequence suggests that it may function in the anabolic flux of carbon from lipid to carbohydrate. Time-lapse image sequences show lipid bodies moving in both directions along hyphae and nuclear magnetic resonance analysis of labeling patterns after supplying 13C-labeled glycerol to either extraradical hyphae or colonized roots shows that there is indeed significant bidirectional translocation between IRM and ERM. We conclude that large amounts of lipid are translocated within the AM fungal colony and that, whereas net movement is from the IRM to the ERM, there is also substantial recirculation throughout the fungus.  (+info)

Synthesis of southern (C1'-C11') and eastern (C8-C18) fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger. (5/385)

Synthesis of the southern C1'-C11' and eastern C8-C18 fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger, was achieved. The southern fragment was synthesized by using the Evans aldol reaction and cis-selective iodoetherification as the key steps in a 9.6% overall yield (7 steps). The eastern fragment was constructed via the Julia coupling reaction and cis-selective iodoetherification in a 3.0% overall yield (8 steps from the known epoxide).  (+info)

Isolation and regeneration of protoplasts from the yeast and mycelial form of the dimorphic zygomycete Benjaminiella poitrasii: role of chitin metabolism for morphogenesis during regeneration. (6/385)

Experimental parameters for isolation and regeneration of protoplasts from the mycelial and yeast form cells of the dimorphic zygomycete Benjamininiella poitrasii are reported. Using a chitosanase containing preparation from Streptomyces sp. MCl we obtained protoplasts after 5 h incubation with a yield of 2+/-0.3 x 10(6) ml(-1) and 3+/-0.4 x 10(7) ml(-1) for the mycelial and yeast form, respectively. During regeneration under conditions triggering dimorphism the two morphological forms were observed after 36 h. Initially, for 10-12 h only an irregular mass was formed as a result of deregulated cell wall synthesis. Among the tested inhibitors influencing cell wall metabolism, chitin metabolism inhibitors showed distinctive effects on the regeneration of protoplasts suggesting that the respective enzymes significantly contribute to determining the morphogenesis of the dimorphic fungus B. poitrasii.  (+info)

PCR amplification and polymorphism analysis of the intergenic spacer region of ribosomal DNA in Tuber borchii. (7/385)

PCR amplification of the complete intergenic spacer region (IGS) of the Tuber borchii nuclear ribosomal repeat was obtained using universal primers CNL 12 and NS1rev. In order to improve amplification yield a specific primer, T1, was selected from a partial sequence of the IGS product. IGS diversity was characterized both at the intraindividual and intraspecific level. The results obtained at the intraindividual level showed 10% varying repeats on ten screened colonies, while at the intraspecific level the IGS polymorphism was evident as difference in length amplification between mycelial strains and fruit bodies: 3.5 kb and 2 kb respectively.  (+info)

Production of a monoclonal antibody specific to the genus Trichoderma and closely related fungi, and its use to detect Trichoderma spp. in naturally infested composts. (8/385)

Studies of the interactions between hyperparasitic fungi and their hosts are severely hampered by the absence of methods that allow the unambiguous identification of individual genera in complex environments that contain mixed populations of fungi, such as soil or compost. This study details the development of a monoclonal antibody (MF2) that allows the detection and recovery of Trichoderma spp. in naturally infested composts, and the visualization of hyperparasitic strains of Trichoderma during antagonistic interactions with their hosts. Murine monoclonal antibody MF2, of immunoglobulin class M (IgM), was raised against a protein epitope of a glycoprotein antigen(s) specific for species of the genus Trichoderma and for the closely related fungi Gliocladium viride, Hypomyces chrysospermus, Sphaerostilbella spp. and Hypocrea spp. MF2 did not react with antigens from Gliocladium catenulatum, Gliocladium roseum, Nectria ochroleuca and Clonostachys spp., nor with a range of unrelated soil- and compost-borne fungi. Extracellular production of the MF2 antigen was constitutive. Western-blotting analysis showed that MF2 bound to a ladder of proteins with apparent molecular masses in the range 35-200 kDa. Immunofluorescence studies showed that MF2 bound strongly to the cell walls of hyphae and phialides and the intercalary and terminal chlamydospores of Trichoderma spp., whereas immunogold electron microscopy revealed strong binding of MF2 to the cell walls and septa of hyphae and to the cell walls of phialoconidia. In immunofluorescence studies of dual cultures of Trichoderma and Rhizoctonia solani, only the cell walls of the hyperparasite, which coiled around the host, were stained by MF2. The specificity of MF2 enabled the development of a combined baiting-ELISA technique for the detection of Trichoderma spp. in naturally infested composts. The specificity of this technique was confirmed by phylogenetic analysis based on sequences of the ITS1-5.8S-ITS2 rRNA-encoding regions of the isolates.  (+info)

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