[Show abstract][Hide abstract] ABSTRACT: "Fairy chemicals", 2-azahypoxanthine (AHX) and 2-aza-8-oxohypoxanthine (AOH), are two novel plant-growth regulating compounds isolated from a fairy ring forming fungus Lepista sordida. In the present study, the effects of AHX and AOH on the accumulation of carotenoids and expression of genes related to carotenoid metabolism were investigated in the juice sacs of Satsuma mandarin (Citrus unshiu Marc.) in vitro. The results showed that AHX and AOH regulated carotenoid metabolism in the citrus juice sacs. Carotenoid accumulation was induced by AHX in the second week and by AOH in the fourth week, respectively. In the meanwhile, the modification of carotenoid accumulation by the AHX and AOH treatments was highly regulated at the transcriptional level. The results presented herein provide new information on the functions of AHX and AOH in plants, and contribute to elucidating the mechanisms by which AHX and AOH stimulate plant growth.
Journal of Agricultural and Food Chemistry 07/2015; 63(32). DOI:10.1021/acs.jafc.5b02455 · 2.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: HML (Hypsizigus marmoreus lectin) was isolated from the mushroom Hypsizigus marmoreus using CM cation exchange, bovine submaxillary gland mucin affinity column and TSK-GEL G3000SW gel filtration chromatography. The results of SDS-PAGE, MALDI-TOF MS and gel filtration analysis of HML indicated that the lectin was a dimer with each subunit of 9.5 kDa. The partial amino acid sequences of HML were determined by N-terminal sequencing of peptides obtained by trypsin or Glu-C endopeptidase digest of the lectin. In the hemagglutination inhibition assay, HML did not bind to any mono- or oligo-saccharides tested. Among the glycoproteins examined, asialo-fetuin was the strongest inhibitor.
[Show abstract][Hide abstract] ABSTRACT: To examine the effect of 2-azahypoxanthine (AHX) on rice plant (Oryza sativa L. cv. Nipponbare) growth, we carried out pot and field experiments. AHX was applied at 50 μM for two weeks at four growth stages (transplanting, tillering, panicle formation and ripening stages) in the pot experiment, and 1 mM AHX at three stages [at rising of seedling in nursery boxes (seedling treatment), transplanting and panicle formation stages] in the field experiment. Both pot and field experiments showed a tendency toward increased panicle number (PN), culm length (CL) and plant dry weights with AHX treatments. Brown rice yields were also improved by AHX treatments, especially when applying at stages of tillering and panicle formation and seedling and transplanting during pot and field experiments, respectively. In the latter, yield increased drastically up to 18.7, 15.8, 9.6 and 5.8% of control. However, panicle length and 1000-grain weight were not affected by AHX application. These results suggested that AHX increased the brown rice yield through its effects on PN and/or CL.
Japan Agricultural Research Quarterly 01/2015; 49(1):45-49. DOI:10.6090/jarq.49.45 · 0.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Three novel compounds, erinaceolactones A to C (1-3), and a known compound (4) were isolated from the culture broth of Hericium erinaceus. The planar structures of 1-3 were determined by the interpretation of spectroscopic data. The absolute configuration of 3 was determined by X-ray crystallography. Although compound 4 had been synthesized, it was isolated from a natural source for the first time. In the bioassay examining plant-growth regulatory activity of these compounds (1-4) and other components of the fungus (5-8), compounds 1, 2, and 4-8 suppressed the growth of lettuce.
[Show abstract][Hide abstract] ABSTRACT: Two new compounds, 10-dehydroxymelleolide D (1) and 13-hydroxymelleolide K (2), along with seven known compounds, 5'-O-methylmelledonal (3), melleolide D (4), 13-hydroxydihydromelleolide (5), melleolide (6), armillarinin (7), armillaridin (8), and armillarikin (9), were isolated from the culture broth of Armillaria sp. Their structures were determined by spectroscopic data analysis. All the compounds inhibited plant growth of lettuce. Melleolide (6) and armillarikin (9) inhibited mycelial growth of Coprinopsis cinerea and/or Flammulina velutipes.
[Show abstract][Hide abstract] ABSTRACT: Two novel compounds, 1 and 7, along with six known compounds (2-6 and 8), were isolated from the edible mushroom Mycoleptodonoides aitchisonii (bunaharitake in Japanese). The structures of the new compounds were determined by the interpretation of spectroscopic data. Compounds 1-4 and 6-8 showed protective activity against endoplasmic reticulum stress-dependent cell death.
[Show abstract][Hide abstract] ABSTRACT: Two-year field examinations to see effects of the principle components of a fungus causing “fairy rings” phenomena on lawns, 2-azahypoxanthine (AHX) and imidazole-4-carboxamide (ICA), on wheat were performed. The treatment of AHX or ICA was performed, in the early (seedling treatment, seed soaking treatment) and late (field treatment) developmental stages, and the resulting number of ears and grain weight per plant increased. AHX treatment increased the number of ears before tillering and ICA treatment increased the number after tillering. The high temperature during tillering stage in 2011 was a stress condition for wheat production in fields. The results indicated that AHX and ICA increased number of tillers and then number of ears, resulting in the increase of the grain yield even though under high-temperature stress.
Field Crops Research 06/2014; 162:6–11. DOI:10.1016/j.fcr.2014.03.008 · 2.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A novel compound (1) and a known one (2) were isolated from the fruiting bodies of Tricholoma flavovirens. Their structures were determined by the interpretation of spectroscopic data. Both compounds showed inhibition effects on the growth of hypocotyl of lettuce with significant differences. In addition, compound 1 showed a promotion effect on the growth of root with significant differences and 2 had the similar tendency to promote the growth.
Acess at: http://www.tandfonline.com/eprint/fJ9YhsZ6bWchhwPDiSgi/full
Bioscience Biotechnology and Biochemistry 05/2014; DOI:10.1080/09168451.2014.905174 · 1.06 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We describe a practical, large-scale synthesis of the "fairy-ring" plant-growth regulator 2-azahypoxanthine (AHX), and its biologically active hydroxyl metabolite (AOH) and riboside derivative (AHXr). AHXr, a biosynthetic intermediate, was synthesized from inosine via a biomimetic route. Biotinylated derivatives of AHX and AHXr were also synthesized as probes for mechanistic studies.
[Show abstract][Hide abstract] ABSTRACT: Pleurocybella porrigens is a mushroom-forming fungus, which had been consumed as a traditional food in Japan. However, in 2004, 55 people got poisoned by eating the mushroom and 17 people among them died of acute encephalopathy. We have already reported the purification, characterization, and cDNA cloning of a lectin from the mushroom (PPL) which might have caused the poisoning. Here, we report the heterologous expression of recombinant PPL by basidiomycete Phanerochaete sordida YK-624. The glyceraldehyde 3-phosphate dehydrogenase gene promoter was used to drive the expression of the PPL gene (ppl) in P. sordida YK-624. Furthermore, the signal peptide of lignin peroxidase which is an extracellular protein was used to secrete rPPL into extracellular region. Seven regenerated clones were cultured on kirk HNHC broth, and the presence of lectin activity in the culture broth was checked by agglutination assays. The results indicated that the culture broth of rPPL-6 clone showed the strongest hemagglutination activity, and it was therefore used for subsequent analysis. The heterologous expression of rPPL by P. sordida YK-624 was confirmed by SDS-PAGE, lectin activity by the hemagglutination assay, and mass of rPPL by MALDI-TOF respectively, indicating that the extracellular secretion of rPPL as active form was successful.
[Show abstract][Hide abstract] ABSTRACT: Rings or arcs of fungus-stimulated plant growth occur worldwide; these are commonly referred to as "fairy rings". In 2010, we discovered 2-azahypoxanthine (AHX), a compound responsible for the fairy-ring phenomenon caused by fungus; AHX stimulated the growth of all the plants tested. Herein, we reveal the isolation and structure determination of a common metabolite of AHX in plants, 2-aza-8-oxohypoxanthine (AOH). AHX is chemically synthesized from 5-aminoimidazole-4-carboxamide (AICA), and AHX can be converted into AOH by xanthine oxidase. AICA is one of the members of the purine metabolic pathway in animals, plants, and microorganisms. However, further metabolism of AICA remains elusive. Based on these results and facts, we hypothesized that plants themselves produce AHX and AOH through a pathway similar to the chemical synthesis. Herein, we demonstrate the existence of endogenous AHX and AOH and a novel purine pathway to produce them in plants.
[Show abstract][Hide abstract] ABSTRACT: An unusual sterol having an unprecedented ether ring (1) and another new sterol (2) were isolated from the fruiting bodies of Stropharia rugosoannulata. Their structures were determined by the interpretation of spectroscopic data. The relative stereochemistry of 1 was determined by X-ray crystallographic analysis.
[Show abstract][Hide abstract] ABSTRACT: The absolute configuration of strophasterol B (1) isolated from the fruiting bodies of Stropharia rugosoannulata was determined by an X-ray crystallographic analysis. Three compounds (2 to 4) were isolated from the mushroom which suppressed or promoted lettuce growth.
[Show abstract][Hide abstract] ABSTRACT: The novel cerebroside, termitomycesphin I (1), and two known cerebrosides (2 and 3) were isolated from the edible mushroom, Termitomyces titanicus. The structures of 1-3 were determined and identified by interpreting the spectroscopic data.
[Show abstract][Hide abstract] ABSTRACT: Makomotindoline (1) was isolated from Makomotake, Zizania latifolia infected with Ustilago esculenta. The structure was determined by the interpretation of spectroscopic data and synthesis. Makomotindoline (1), its l-Glc isomer (2) and its aglycon (3) were synthesized and their effects on rat glioma cells showed adverse effects on the cell growth.
[Show abstract][Hide abstract] ABSTRACT: Leccinine A (1) along with a known compound (2), were isolated from the edible mushroom Leccinum extremiorientale. The structure of 1 was determined by the interpretation of spectral data. Leccinine A showed protective activity against endoplasmic reticulum stress-dependent cell death. Seven analogues (3–9) of 1 were synthesized in order to evaluate the structure–activity relationship, and the result indicated that the formamide group of 1 was indispensable for the activity.
[Show abstract][Hide abstract] ABSTRACT: Three novel sterols, gargalols A–C (1–3), and four known ones were isolated from the edible mushroom Grifola gargal. The structures of 1–7 were determined or identified by the interpretation of spectroscopic data. Compounds 1–5 suppressed the formation of osteoclast without toxicity.
[Show abstract][Hide abstract] ABSTRACT: Five fatty acid amides, termitomycamides A to E (1 to 5), were isolated from the giant edible mushroom Termitomyces titanicus. The structures of 1-5 were determined by the interpretation of spectral data and/or synthesis. Compounds 2 and 5 showed protective activity against endoplasmic reticulum stress-dependent cell death.
[Show abstract][Hide abstract] ABSTRACT: Rings or arcs of fungus-regulated plant growth occur often on the floor of woodlands, in agricultural areas, and in grasslands worldwide. These rings are commonly called "fairy rings". A plant-growth regulating compound was isolated from a fairy ring forming fungus, Lepista sordida , and its chemical structure was identified as imidazole-4-carboxamide (ICA) by spectroscopic analyses including single-crystal X-ray diffraction techniques. ICA inhibited the growth of turfgrass and rice seedling. On the other hand, in a greenhouse experiment, this compound increased rice grain yield by 26% compared with control.
Journal of Agricultural and Food Chemistry 09/2010; 58(18):9956-9. DOI:10.1021/jf101619a · 2.91 Impact Factor