JSM Mycotoxins
Online ISSN : 1881-0128
Print ISSN : 0285-1466
ISSN-L : 0285-1466
Volume 59 , Issue 2
Showing 1-8 articles out of 8 articles from the selected issue
Review
  • Masahiro OKADA, Jianhua QI, Youji SAKAGAMI
    Type: Review
    2009 Volume 59 Issue 2 Pages 55-66
    Published: 2009
    Released: November 05, 2009
    JOURNALS FREE ACCESS
    The ComX pheromone is a post-translationally modified oligopeptide that stimulates natural genetic competence controlled by quorum sensing in Bacillus subtilis. The structure of the ComXRO-E-2 pheromone produced by strain RO-E-2 was determined. In the pheromone molecule, a geranyl group is bound to the tryptophan residue, which results in the formation of a tricyclic ring structure. Molds in the genus Phytophthora are some of the most destructive phytopathogens known. An important biological event in Phytophthora is sexual reproduction. A factor known as hormone α1 is secreted by the A1 mating type, and this induces the formation of oospores in the A2 mating type. The structure of hormone α1 is a C-20 linear isoprenoid and the absolute stereochemistry was determined by chemical synthesis.
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Regular Papers
  • Hitoshi NAGASHIMA, Hiroyuki NAKAGAWA, Masayo KUSHIRO, Keiko IWASHITA
    Type: Regular Papers
    2009 Volume 59 Issue 2 Pages 67-73
    Published: 2009
    Released: November 05, 2009
    JOURNALS FREE ACCESS
    To elucidate the molecular mechanism underlying the toxicity of the Fusarium mycotoxin nivalenol, we investigated the involvement of stress-activated MAP kinases (SAPKs; c-Jun Nterminal kinases (JNKs) and p38s) in nivalenol-caused cytotoxicity and interleukin (IL) -8 secretion in human promyelocytic leukemia HL60 cells. Nivalenol treatment for 24 h increased the phosphorylated (i.e., the active-form) JNKs with maximum effect at 1 μg/mL; when nivalenol was given at this concentration in a time-series experiment, phosphorylated JNK quantity peaked at 12 h and then decreased. Essentially the same results were obtained for phosphorylated (active-form) p38s. To elucidate the functions of SAPKs, we investigated the effects of the JNK-specific inhibitor SP600125 and the p38-specific inhibitor SB203580 on nivalenol-caused cytotoxicity and IL-8 secretion. Nivalenol hindered cell proliferation regardless of the presence or absence of SAPK-specific inhibitors. However, co-treatment with SAPK inhibitors reduced this effect, indicating that JNKs and p38s play roles in nivalenolassociated retardation of cell proliferation. SP600125 significantly reduced nivalenol-induced IL-8 secretion, indicating that JNKs contribute to this phenomenon. SB203580 moderately lessened nivalenol-elicited IL-8 secretion, however, the contribution of p38s to nivalenolinduced IL-8 secretion appears to be meaningful, because SB203580 alone markedly increased IL-8 secretion.
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  • Tomoo HOSOE, Hiroyoshi MORIYAMA, Daigo WAKANA, Takeshi ITABASHI, Ken-i ...
    Type: Regular Papers
    2009 Volume 59 Issue 2 Pages 75-82
    Published: 2009
    Released: November 05, 2009
    JOURNALS FREE ACCESS
    Dihydroterrein (1) and terrein (2) were isolated from methanol extracts of the solid culture of Asperillus novofumigatus IFM 55215. Both 1 and 2 inhibited human platelet aggregation induced by collagen at a concentration of 5.0 × 102 μmol/L in vitro and they displayed slight inhibitory effects when platelet aggregation was induced by adenosine diphosphate (ADP). Inhibitory activity of dihydroterrein diacetate (3) and terrein diacetate (4) on platelet aggregation was also examined. Compound 4 was found to possess the highest inhibitory effect on both collagen- and ADP-induced platelet aggregation among 1 - 4.
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Proceedings of the 65th Meeting
Special Lecture
  • proposals for polluted water treatment by applying flocculating activity of cross-linked poly-γ-glutamic acid
    Makoto TANIGUCHI
    Type: Special Lecture
    2009 Volume 59 Issue 2 Pages 83-93
    Published: 2009
    Released: November 05, 2009
    JOURNALS FREE ACCESS
    Cross-linked poly-γ-glutamic acid (C-L γ-PGA) markedly purified polluted water collected from rivers and ponds by flocculation and precipitation. This effect of C-L γ-PGA occasionally required pretreatment with polyaluminum chloride (PAC). Components of polluted water in rivers or ponds are generally thought to be clay minerals, microorganisms and chemical compounds. In this study, the flocculating activities of C-L γ-PGA against suspensions of bentonite, diatomaceous earth, Escherichia coli and Mycrocystis aeruginosa, and against solutions of crystal violet and bisphenol A were investigated. The mode of action of C-L γ-PGA is thought to be based on electrostatic interaction between flocculants, C-L γ-PGA and PAC, and the surface of polluted water components, which may lead to neutralization of the zetapotential of those components.
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Symposium
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