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71.
Dillapiol and Apiol as specific inhibitors of the biosynthesis of aflatoxin G1 in Aspergillus parasiticus 总被引:1,自引:0,他引:1
Razzaghi-Abyaneh M Yoshinari T Shams-Ghahfarokhi M Rezaee MB Nagasawa H Sakuda S 《Bioscience, biotechnology, and biochemistry》2007,71(9):2329-2332
Dillapiol was isolated from the essential oil of dill as a specific inhibitor of aflatoxin G1 production. It inhibited aflatoxin G1 production by Aspergillus parasiticus with an IC50 value of 0.15 microM without inhibiting aflatoxin B1 production or fungal growth. Apiol and myristicin, congeners of dillapiol, showed similar activity with IC50 values of 0.24 and 3.5 microM, respectively. 相似文献
72.
Youhei Tanaka Naohiro Hayashibara Tomoya Enokido Makoto Takizawa 《Cluster computing》2007,10(1):81-93
In this paper, we discuss how to realize fault-tolerant applications on distributed objects. Servers supporting objects can
be fault-tolerant by taking advantage of replication and checkpointing technologies. However, there is no discussion on how
application programs being performed on clients are tolerant of clients faults. For example, servers might block in the two-phase
commitment protocol due to the client fault. We newly discuss how to make application programs fault-tolerant by taking advantage
of mobile agent technologies where a program can move from a computer to another computer in networks. An application program
to be performed on a faulty computer can be performed on another operational computer by moving the program in the mobile
agent model. In this paper, we discuss a transactional agent model where a reliable and efficient application for manipulating objects in multiple computers is realized in the mobile agent
model. In the transactional agent model, only a small part of the application program named routing subagent moves around computers. A routing subagent autonomously finds a computer which to visit next. We discuss a hierarchical navigation
map which computer should be visited price to another computer in a transactional agent. A routing subagent makes a decision
on which computer visit for the hierarchical navigation map. Programs manipulating objects in a computer are loaded to the
computer on arrival of the routing subagent in order to reduce the communication overhead. This part of the transactional
agent is a manipulating subagent. The manipulation subagent still exists on the computer even after the routing subagent leaves the computer in order to hold
objects until the commitment. We assume every computer may stop by fault while networks are reliable. There are kinds of faulty
computers for a transactional agent; current, destination, and sibling computers where a transactional agent now exists, will move, and has visited, respectively. The types of faults are detected
by neighbouring manipulation subagents by communicating with each other. If some of the manipulation subagents are faulty,
the routing subagent has to be aborted. However, the routing subagent is still moving. We discuss how to efficiently deliver
the abort message to the moving routing subagent. We evaluate the transactional agent model in terms of how long it takes
to abort the routing subagent if some computer is faulty.
相似文献
Makoto TakizawaEmail: |
73.
Akiko Takabatake Nozomi Kawazoe Shingo Izawa 《Applied microbiology and biotechnology》2015,99(6):2805-2814
Yro2 and its paralogous protein Mrh1 of Saccharomyces cerevisiae have seven predicted transmembrane domains and predominantly localize to the plasma membrane. Their physiological functions and regulation of gene expression have not yet been elucidated in detail. We herein demonstrated that MRH1 was constitutively expressed, whereas the expression of YRO2 was induced by acetic acid stress and entering the stationary phase. Fluorescence microscopic analysis revealed that Mrh1 and Yro2 were distributed as small foci in the plasma membrane under acetic acid stress conditions. The null mutants of these genes (mrh1?, yro2?, and mrh1?yro2?) showed delayed growth and a decrease in the productivity of ethanol in the presence of acetic acid, indicating that Yro2 and Mrh1 are involved in tolerance to acetic acid stress. 相似文献
74.
Kazutaka Sawada Tomoya Sato Hiroshi Hamajima Lahiru Niroshan Jayakody Miyo Hirata Mikako Yamashiro Marie Tajima Susumu Mitsutake Koji Nagao Keisuke Tsuge Fumiyoshi Abe Kentaro Hanada Hiroshi Kitagaki 《Applied and environmental microbiology》2015,81(11):3688-3698
In nature, different microorganisms create communities through their physiochemical and metabolic interactions. Many fermenting microbes, such as yeasts, lactic acid bacteria, and acetic acid bacteria, secrete acidic substances and grow faster at acidic pH values. However, on the surface of cereals, the pH is neutral to alkaline. Therefore, in order to grow on cereals, microbes must adapt to the alkaline environment at the initial stage of colonization; such adaptations are also crucial for industrial fermentation. Here, we show that the yeast Saccharomyces cerevisiae, which is incapable of synthesizing glucosylceramide (GlcCer), adapted to alkaline conditions after exposure to GlcCer from koji cereal cultured with Aspergillus kawachii. We also show that various species of GlcCer derived from different plants and fungi similarly conferred alkali tolerance to yeast. Although exogenous ceramide also enhanced the alkali tolerance of yeast, no discernible degradation of GlcCer to ceramide was observed in the yeast culture, suggesting that exogenous GlcCer itself exerted the activity. Exogenous GlcCer also increased ethanol tolerance and modified the flavor profile of the yeast cells by altering the membrane properties. These results indicate that GlcCer from A. kawachii modifies the physiology of the yeast S. cerevisiae and demonstrate a new mechanism for cooperation between microbes in food fermentation. 相似文献
75.
A major challenge associated with the fermentation of lignocellulose-derived hydrolysates is improved ethanol production in the presence of fermentation inhibitors, such as acetic and formic acids. Enhancement of transaldolase (TAL) and formate dehydrogenase (FDH) activities through metabolic engineering successfully conferred resistance to weak acids in a recombinant xylose-fermenting Saccharomyces cerevisiae strain. Moreover, hybridization of the metabolically engineered yeast strain improved ethanol production from xylose in the presence of both 30 mM acetate and 20 mM formate. Batch fermentation of lignocellulosic hydrolysate containing a mixture of glucose, fructose and xylose as carbon sources, as well as the fermentation inhibitors, acetate and formate, was performed for five cycles without any loss of fermentation capacity. Long-term stability of ethanol production in the fermentation phase was not only attributed to the coexpression of TAL and FDH genes, but also the hybridization of haploid strains. 相似文献
76.
The mechanism of regulation of PPARG expression during the osteogenesis of human mesenchymal stem cells (MSCs) was investigated on an extracellular matrix (ECM) model that mimicked the stepwise osteogenesis ECM. Three matrices that mimicked the ECM of MSCs (stem cell matrices), the early stage ECM (early stage matrices), and the late stage ECM (late stage matrices) of osteogenesis were prepared and compared. The matrices showed different effects on the Wnt/β-catenin signal. The β-catenin signal was activated by endogenous Wnt through interaction with chondroitin sulfate chains to suppress PPARG expression on the stem cell matrices and early stage matrices but not on late stage matrices. 相似文献
77.
Nishizaki C Nishikawa M Yata T Yamada T Takahashi Y Oku M Yurimoto H Sakai Y Nakanishi K Takakura Y 《Free radical biology & medicine》2011,51(3):773-779
Surgical trauma, which is inevitably associated with the surgical removal of cancer, has been reported to accelerate tumor metastasis. The close association of reactive oxygen species with the trauma and tumor metastasis supports the possibility of using antioxidants for the inhibition of metastasis. To inhibit surgical trauma-enhanced peritoneal dissemination, human catalase (hCAT) derivatives, i.e., hCAT-nona-arginine peptide (hCAT-R9) and hCAT-albumin-binding peptide (hCAT-ABP), were designed to increase the retention time of the antioxidant enzyme in the abdominal cavity after intraperitoneal administration. Both 125I-labeled derivatives showed significantly prolonged retention in the cavity compared to 125I-hCAT. Cauterization of the cecum of mice with a hot iron, an experimental model of surgical trauma, induced abdominal adhesions. In addition, cauterization followed by colon26 tumor cell inoculation increased lipid peroxidation in the cecum and mRNA expression of molecules associated with tissue repair/adhesion and inflammation in the peritoneum. hCAT derivatives significantly suppressed the increased mRNA expression. The cauterization also increased the number of tumor cells in the abdominal organs, and the number was significantly reduced by hCAT-R9 or hCAT-ABP. These results indicate that hCAT-R9 and hCAT-ABP, both of which have a long retention time in the peritoneal cavity, can be effective at inhibiting surgery-induced peritoneal metastasis. 相似文献
78.
Hirata T Terai T Komatsu T Hanaoka K Nagano T 《Bioorganic & medicinal chemistry letters》2011,21(20):6090-6093
We have developed a red-emitting fluorescent K(+) probe, B3TAC, which also shows a wavelength shift upon binding to K(+). The probe was synthesized by conjugating a cryptand-based chelator, 2-triazacryptand [2,2,3]-1-(2-methoxyethoxy)benzene (TAC), to position 3 of the BODIPY fluorophore through a styryl linker. In water-acetonitrile mixed solvent, it responded to K(+) in the physiological concentration range with high selectivity over Na(+) and other metal ions. B3TAC is potentially useful for measuring cellular K(+) ion concentration, as well as for simple, naked-eye detection of K(+) in solution. 相似文献
79.
Genomics of fish IL-17 ligand and receptors: a review 总被引:2,自引:0,他引:2
Interleukin-17 (IL-17) is a cytokine family composed of six ligands (A–F). Especially, the IL-17A and IL-17F are best characterized cytokines of IL-17 family cytokine. These are produced by Th17 cells and induce the expression of many mediators of inflammation properties. In addition, the five member of IL-17 receptor family (RA-RE) have been identified in mammals. Although the research on fish IL-17 is a little to date, this review discusses some of the recent advances in research on IL-17 ligand and receptor genes in fish. IL-17 family member was chosen from the fish genome database, and its structure and phylogeny is analyzed in detail. Moreover, invertebrate IL-17 genes are also discussed, and the isolation and current status of fish IL-17 receptor genes are summarized. Comparative genomic analysis of the IL-17 family among mammals, teleost and invertebrates provided new insights. Novel IL-17 ligand (IL-17N) was identified from teleost, moreover it was suggested that IL-17N may be a teleost specific ligand by synteny and phylogenetic analysis. On the other hand, IL-17 receptors are well conserved between mammal and teleost, the five member of IL-17 receptor family: IL-17RA-RE were found on the teleost genome. In addition, the IL-17RA gene was duplicated in tandem on the stickleback and medaka genome. Knowledge about the IL-17 ligand/receptor in fish is very limited. Therefore this review will hopefully encourage future studies of IL-17 in fish. 相似文献
80.
A global experiment suggests climate warming will not accelerate litter decomposition in streams but might reduce carbon sequestration 总被引:2,自引:0,他引:2
Boyero L Pearson RG Gessner MO Barmuta LA Ferreira V Graça MA Dudgeon D Boulton AJ Callisto M Chauvet E Helson JE Bruder A Albariño RJ Yule CM Arunachalam M Davies JN Figueroa R Flecker AS Ramírez A Death RG Iwata T Mathooko JM Mathuriau C Gonçalves JF Moretti MS Jinggut T Lamothe S M'Erimba C Ratnarajah L Schindler MH Castela J Buria LM Cornejo A Villanueva VD West DC 《Ecology letters》2011,14(3):289-294
The decomposition of plant litter is one of the most important ecosystem processes in the biosphere and is particularly sensitive to climate warming. Aquatic ecosystems are well suited to studying warming effects on decomposition because the otherwise confounding influence of moisture is constant. By using a latitudinal temperature gradient in an unprecedented global experiment in streams, we found that climate warming will likely hasten microbial litter decomposition and produce an equivalent decline in detritivore-mediated decomposition rates. As a result, overall decomposition rates should remain unchanged. Nevertheless, the process would be profoundly altered, because the shift in importance from detritivores to microbes in warm climates would likely increase CO(2) production and decrease the generation and sequestration of recalcitrant organic particles. In view of recent estimates showing that inland waters are a significant component of the global carbon cycle, this implies consequences for global biogeochemistry and a possible positive climate feedback. 相似文献