Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 75 , Issue 8
Showing 1-43 articles out of 43 articles from the selected issue
Award Reviews
  • Masahiro OKADA
    2011 Volume 75 Issue 8 Pages 1413-1417
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Bacillus subtilis and related bacilli produce a post-translationally modified oligopeptide, ComX pheromone, that stimulates natural genetic competence controlled by quorum sensing. The ComX pheromones are formed by geranylation or farnesylation on a tryptophan residue at the 3 position of its indole ring. This results in the formation of a tricyclic structure including, a newly formed five-membered ring, similar to proline. Isoprenylation of ComX to form ComX pheromones is essential for pheromonal activity, and is functionally more crucial than its amino acid sequence. The ComX pheromone is the first example of isoprenoidal modifiations of tryptophan residues in living organisms and post-translational isoprenylation of any amino acid in prokaryotes. Because the presence of geranylated compounds is unusual in primary and secondary metabolites outside the plant kingdom, post-translational geranylation in bacilli is unprecedented in nature.
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  • Arata YAJIMA
    2011 Volume 75 Issue 8 Pages 1418-1429
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Microbial signaling molecules such as autoinducers and microbial hormones play important roles in intercellular communication in microorganisms. Information transfer between the individual cells of a microorganism is one of the most important biological events among them. Researchers often suffer from extremely low levels of microbial signaling molecule contents, which prevent them from understanding chemistry and biology of intercellular communication in microorganisms. Chemical synthesis is a powerful tool to obtain sufficient amounts of sample and to clarify the structure of a molecule. This review focuses on the synthesis and stereochemistry-bioactivity relationships of five microbial signaling molecules, Vibrio cholerae autoinducer-1 (CAI-1), AI-2 precursor (DPD), an acylhomoserine lactone from Rhizobium leguminosarum (small bacteriocin), a diffusible extracellular factor of Xanthomondas campestris pv. campestris, and Phytophthora mating hormone α1.
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Organic Chemistry Regular Papers
  • Uswatun Hasanah ZAIDAN, Mohd Basyaruddin ABDUL RAHMAN, Siti Salhah OTH ...
    2011 Volume 75 Issue 8 Pages 1446-1450
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    The utilization of natural mica as a biocatalyst support in kinetic investigations is first described in this study. The formation of lactose caprate from lactose sugar and capric acid, using free lipase (free-CRL) and lipase immobilized on nanoporous mica (NER-CRL) as a biocatalyst, was evaluated through a kinetic study. The apparent kinetic parameters, Km and Vmax, were determined by means of the Michaelis-Menten kinetic model. The Ping-Pong Bi-Bi mechanism with single substrate inhibition was adopted as it best explains the experimental findings. The kinetic results show lower Km values with NER-CRL than with free-CRL, indicating the higher affinity of NER-CRL towards both substrates at the maximum reaction velocity (Vmax,app>Vmax). The kinetic parameters deduced from this model were used to simulate reaction rate data which were in close agreement with the experimental values.
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  • Daichi OGURO, Hidenori WATANABE
    2011 Volume 75 Issue 8 Pages 1502-1505
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    The synthesis and sensory evaluation of enantiomeric sets of sedanenolide (1) and 3-butylphthalide (3) are described. The asymmetric synthesis was achieved via the intramolecular Diels-Alder reaction of chiral propargylester (5) which was prepared from optically active propargyl alcohol (4) and 2,4-pentadienoic acid. The sensory evaluation of these enantiomers revealed that there were distinct differences between their aroma character and odor threshold.
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  • Yong LI, Man-Li ZHANG, Bin CONG, Si-Ming WANG, Mei DONG, Franço ...
    2011 Volume 75 Issue 8 Pages 1554-1556
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Achillinin A (2β,3β-epoxy-1α,4β,10α-trihydroxyguai-11(13)-en-12,6α-olide, 1), a new guaianolide isolated from the flower of Achillea millefolium, exhibited potential antiproliferative activity to A549, RERF-LC-kj and QG-90 cells with 50% inhibitory concentration (IC50) values of 5.8, 10 and 0.31 μM, respectively.
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Organic Chemistry Notes
  • Yumiko SANNOHE, Shuichi GOMI, Takashi MURATA, Makoto OHYAMA, Kumiko YO ...
    2011 Volume 75 Issue 8 Pages 1606-1607
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Cacao beans are composed of cacao nibs and germs. Although numerous chemical and physiological studies on cacao nib compounds have been reported, there is little information on cacao germ compounds. We therefore analyzed an extract from the cacao germ, and found two compounds that were specific to the germ. One of these two compounds was identified as the new glycosylated abscisic acid metabolite, dihydrophaseic acid-4′-O-6″-(β-ribofuranosyl)-β-glucopyranoside, and the other as the known compound, dihydrophaseic acid-4′-O-β-D-glucopyranoside.
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  • Kenji KOBATA, Makoto MIMURA, Mai SUGAWARA, Tatsuo WATANABE
    2011 Volume 75 Issue 8 Pages 1611-1614
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Stable isotope-labeled precursors were synthesized for an analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to elucidate the biosynthetic flow of capsaicinoids, capsinoids, and capsiconinoids. [1′-13C][5-2H]-Vanillin was prepared by the condensation of guaiacol with [13C]-chloroform and a D2O treatment. Labeled vanillylamine, vanillyl alcohol, ferulic acid, and coniferyl alcohol were prepared from the labeled vanillin. The labeled vanillylamine was converted to labeled capsaicinoid in a crude enzyme solution extracted from pungent Capsicum fruits.
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  • Masayoshi YAMADA, Kazuhiko NAKAMURA, Taeko WATABE, Osamu OHNO, Masaru ...
    2011 Volume 75 Issue 8 Pages 1628-1630
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    The EtOH extract of tarragon Artemisia dracunculus, a perennial herb in the family Asteraceae, was found to potently inhibit α-melanocyte-stimulating hormone (α-MSH) induced melanin production in B16 mouse melanoma cells. Bioassay-guided fractionation led to the isolation of two alkamide compounds, isobutyl (1) and piperidiyl (2) amides of undeca-2E,4E-dien-8,10-dynoic acid. The respective EC50 values for melanin biosynthesis inhibition were 1.8 and 2.3 μg/mL for 1 and 2.
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Biochemistry & Molecular Biology Regular Papers
  • Nanae SHIMONO, Yuuki NISHIMURA, Hiroshi KAMIGUCHI, Yoshihisa NISHIKAWA
    2011 Volume 75 Issue 8 Pages 1451-1455
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    We cloned a novel human mannosyltransferase-like gene, designated Hmat-Xa, as a gene homologous to the Drosophila GC15914 gene encoding the 9QVXN0 protein: see “Project Report for FY2002 on the ‘Construction of Libraries of Human Genes Participating in Glycosylation’ project” 43–45 (2003), New Energy and Industrial Technology Development Organization (NEDO), NEDO and Research Association for Biotechnology, Tokyo, Japan (in Japanese). After that, the GTDC1 gene, as reported by Zhao et al., DNA Cell Biol., 23, 183–187 (2004), was found to be the same as the Hmat-Xa gene. Domain EXFGI/L/VX2L/VE in the Hmat-Xa protein, also present in both human mannosyltransferase II/III and mannosyltransferase IV/V, which are involved in the synthesis of lipid-linked oligosaccharides, and some bacterial mannosyltransferases. A real-time PCR study of Hmat-Xa mRNA expression in human normal and tumor multiple tissue cDNA identified its tissue-specific expression and its remarkable expression in colon adenocarcinoma as compared to the normal counterpart. Thus the elevated expression of Hmat-Xa might serve as a candidate marker for colon adenocarcinoma.
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  • Dipali Rani GUPTA, Swapan Kumar PAUL, Yasuo OOWATARI, Yasuhiro MATSUO, ...
    2011 Volume 75 Issue 8 Pages 1456-1465
    Published: August 23, 2011
    Released: August 23, 2011
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    Nine sam mutants that undergo sexual differentiation without requiring starvation in Schizosaccharomyces pombe were previously isolated. In this study, we identified a nonsense mutation on the pka1 locus in the sam6 mutant. pka1 encodes a catalytic subunit of protein kinase A (PKA). Replacement and overexpression of pka1 suppressed the KCl sensitivity and hyper-mating phenotype of sam6, confirming that sam6 is an allele of pka1. To characterize further the regulation of Pka1, we tested the physical interaction between Pka1 and Cgs1 (a regulatory subunit of PKA). Pka1 and Cgs1 physically interacted under glucose-limited conditions but not under glucose-rich conditions. In addition, the formation of a Pka1-Cgs1 complex was detected under glucose-limited conditions by Blue Native PAGE. Furthermore, the Pka1 protein was found to be phosphorylated under glucose-starved conditions, and at the same time its localization shifted from the nucleus towards the cytoplasm (mainly the vacuoles), suggesting a strong relationship among phosphorylation, complex formation, and the cytoplasmic distribution of Pka1.
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  • Takehiko YOKOYAMA, Masafumi AMANO, Masae SEKINE, Hiroshi HOMMA, Masaha ...
    2011 Volume 75 Issue 8 Pages 1481-1484
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Immunohistochemical localization (cellular localization) of endogenous D-aspartate in the marine brown alga Sargassum fusiforme was investigated by the use of a specific polyclonal antibody raised against D-aspartate. D-Aspartate immunoreactivity was evident in the medullary layer in the blade of the alga, and weak staining was found in the cortical layer, whereas epidermal cells were found to lack D-aspartate. Within the cells of the layers, immunoreactivity was confirmed only in the cytosol and not in the cell wall, chloroplast, or vacuole. These results suggest that D-aspartate is present in S. fusiforme cells, and excludes the possibility that it is derived from attached or symbiotic organisms such as marine bacteria. This is the first report describing the localization of free D-aspartate in plant cells.
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  • Hiroyuki NAGAI, Tsuyoshi GOTO, Nobuyuki TAKAHASHI, Tatsuya KUSUDOH, Yo ...
    2011 Volume 75 Issue 8 Pages 1485-1489
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    A useful method employing liquid chromatography mass spectrometry (LC/MS) and a stable isotope was developed for simultaneous examination of major metabolism in adipocytes, de novo fatty acid synthesis, glycerol output, and glucose uptake with high sensitivity. The addition of thiazolidinediones, potent agonists of peroxisome proliferator-activated receptors-γ, for 10 d increased glucose uptake in a dose-dependent manner. Fatty acid (FA) synthesis increased at low concentrations of thiazolidinediones (TZDs) and decreased at high concentrations. It is important to assess adipocytes from various examples of metabolism, because each example of adipocyte metabolism is directly related to obesity or metabolic syndrome in various ways. The technique makes metabolic examination easier than conventional methods by means of radioisotopes and makes it possible to identify metabolites and to apply them in biomarker screening.
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  • Takayasu KAWASAKI, Kenji ONODERA, Shunsuke KAMIJO
    2011 Volume 75 Issue 8 Pages 1496-1501
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    Since the soluble oligomers of 42-residue amyloid β (Aβ42) might be neurotoxins at an early stage of Alzheimer’s disease (AD), inhibition of soluble Aβ42 oligomerization should be effective in the treatment of AD. We have found by phage display that a 7-residue peptide, SRPGLRR, exhibited inhibitory activity against soluble 37/48 kDa oligomers of Aβ42. In the present study, we newly prepared 3- and 4-residue random peptides libraries and performed pannings of them against soluble Aβ42 to search for important factors in the inhibition of Aβ42 oligomerization. After the fifth round, arginine-containing peptides were enriched in both libraries. SDS–PAGE and size-exclusion chromatography indicated that the inhibitory activities of 4-residue peptides against the soluble 37/48 kDa oligomers of Aβ42 were higher than those of the 3-residue peptides, and RFRK exhibited strong inhibitory activity as well as SRPGLRR. These short peptides should be useful for the suppression of soluble Aβ42 oligomer formation.
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  • Eriko MATSUO, Toshihiro NAGAMINE, Shogo MATSUMOTO, Kazuhide TSUNEIZUMI
    2011 Volume 75 Issue 8 Pages 1511-1515
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Nucleostemin (NS), a nucleolar guanosine triphosphate (GTP)-binding protein, plays significant roles in cell cycle progression and ribosomal biogenesis. Drosophila Nucleostemin 2 (NS2), a member of the Drosophila NS family, regulates early eye development and is essential to cell survival in vivo, but the underlying mechanisms have yet to be clarified. Biochemical analysis using the recombinant NS2 protein indicated that NS2 has GTPase activity. Immunohistochemistry revealed that NS2 changes in subcellular locus from the nucleolus to the nucleoplasm during larval development, and that a mutation in the ATP/GTP-binding site motif A (p-loop) prevents nuclear localization of NS2 and results in cytoplasmic distribution. Furthermore, downregulation of NS2 altered the rRNA proportions between the nucleus and the cytoplasm. These results suggest that NS2 at least requires GTP to import into the nucleoplasm.
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  • Yinxia LI, Manabu ISHIDA, Hiroyuki ASHIDA, Takahiro ISHIKAWA, Hitoshi ...
    2011 Volume 75 Issue 8 Pages 1524-1532
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    We report the molecular characterization and physiological function of a novel L-aspartate dehydrogenase (AspDH). The purified enzyme was a 28-kDa dimeric protein, exhibiting high catalytic activity for L-aspartate (L-Asp) oxidation using NAD and/or NADP as cofactors. Quantitative real-time PCR analysis indicated that the genes involved in the AspDH gene cluster, poly-3-hydroxyalkanoate (PHA) biosynthesis, and the TCA cycle were substantially induced by L-Asp in wild-type cells. In contrast, expression of the aspartase and aspartate aminotransferase genes was substantially induced in the AspDH gene knockout mutant (ΔB3576) but not in the wild type. GC-MS analyses revealed that the wild-type strain synthesized poly-3-hydroxybutyrate from fructose or L-Asp, whereas the ΔB3576 mutant did not synthesize PHA from L-Asp. AspDH gene cluster products might be involved in the biosynthesis of the PHA precursor, revealing that AspDH was a non-NadB type enzyme, and thus entirely different from the previously reported NadB type enzymes working in NAD biosynthesis.
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  • Saori YAMAWAKI, Takafumi YAMASHINO, Hanayo NAKANISHI, Takeshi MIZUNO
    2011 Volume 75 Issue 8 Pages 1533-1539
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    The developmental programs of Physcomitrella patens, a basal lineage of land plants, are regulated by phytohormones and light-signaling responses. In this study, our attention was focused on the HY5-family of transcription factors, which are known to play important roles immediately downstream of photoreceptors during the early photomorphogenesis of Arabidopsis thaliana. We retrieved two HY5-homologs, named PpHY5a and PpHY5b, from the whole genome sequence database of P. patens. Arabidopsis transgenic plants overproducing the basic leucine zipper (bZIP) domain of PpHY5a exhibited a phenotype of short hypocotyls, suggesting a functional relationship between PpHY5 and Arabidopsis HY5. A loss-of-function Δhy5a Δhy5b double mutant was defective in the vigorous protrusion of caulonema cells from the protonema networks of P. patens under light and dark conditions. These results suggest that the function of HY5-homologs in P. patens is evolutionarily conserved, and is implicated in a process of caulonema development.
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  • Shao-Xiang WANG, Huai-Qiang JU, Kai-Sheng LIU, Jia-Xuan ZHANG, Xiao WA ...
    2011 Volume 75 Issue 8 Pages 1540-1545
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    SNX-2112 is a heat shock protein 90 (Hsp90) inhibitor with anticancer properties currently in clinical trials. This study investigated the effects of SNX-2112 on inhibition of cell growth, the cell cycle, and apoptosis in MCF-7 human breast cancer cells, in addition to the various molecular mechanisms. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis suggest that SNX-2112 inhibits cell growth in a time- and dose-dependent manner more potently than 17-(allylamino)-17-demethoxygeldanmycin (17-AAG), a traditional Hsp90 inhibitor, probably as a result of cell-cycle arrest at the G2/M phase and the induction of apoptosis. Downregulation of Bcl-2 and Bcl-xL, upregulation of Bax, cleavage of caspase-9 and poly (ADP-ribose) polymerase (PARP), and degradation of the breast cancer-related Hsp90 client proteins human epidermal growth factor receptor-2 (HER2), Akt, Raf-1, and nuclear factor kappa-B kinase (IKK) were observed in SNX-2112 treated cells by Western blot assay. These findings suggest that the molecular mechanisms of cell-growth inhibition by SNX-2112 involve activation of the mitochondrial apoptotic pathway and the degradation of breast cancer-related proteins.
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  • Mitsuaki SANADA, Kouichi KURODA, Mitsuyoshi UEDA
    2011 Volume 75 Issue 8 Pages 1546-1553
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    GTS1 of Saccharomyces cerevisiae is a pleiotropic gene. Its induction leads to a variety of biological phenomena represented by cell aggregation. The C-terminal polyglutamine sequence in Gts1p is indispensable for its pleiotropy and nuclear localization. This sequence is often observed in polyglutamine diseases, such as Huntington disease, and is believed to induce protein aggregation, leading to cell death. In this study, protein aggregates were formed in a polyglutamine-dependent manner in cells inducing GTS1, and heat-shock protein family, translation elongation factor, and mitochondrial proteins were trapped in Gts1p-mediated protein aggregates. Moreover, the polyglutamine sequence of Gts1p was indispensable to the induction of reactive oxygen species (ROS) production and apoptosis. Deletion of the genes encoding Por1p and Yhb1p altered the profiles of ROS production and apoptosis caused by GTS1 induction, suggesting that the trapping of these proteins in Gts1p-mediated protein aggregates inhibits the intrinsic functions of these proteins.
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  • Momoko KOBAYASHI, Hironori HONDOH, Haruhide MORI, Wataru SABURI, Masay ...
    2011 Volume 75 Issue 8 Pages 1557-1563
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Dextran glucosidase from Streptococcus mutans (SmDG), which belongs to glycoside hydrolase family 13 (GH13), hydrolyzes the non-reducing terminal glucosidic linkage of isomaltooligosaccharides and dextran. Thermal deactivation of SmDG did not follow the single exponential decay but rather the two-step irreversible deactivation model, which involves an active intermediate having 39% specific activity. The presence of a low concentration of CaCl2 increased the thermostability of SmDG, mainly due to a marked reduction in the rate constant of deactivation of the intermediate. The addition of MgCl2 also enhanced thermostability, while KCl and NaCl were not effective. Therefore, divalent cations, particularly Ca2+, were considered to stabilize SmDG. On the other hand, CaCl2 had no significant effect on catalytic reaction. The enhanced stability by Ca2+ was probably related to calcium binding in the β→α loop 1 of the (β⁄α)8 barrel of SmDG. Because similar structures and sequences are widespread in GH13, these GH13 enzymes might have been stabilized by calcium ions.
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  • Tomoko MIYAKE, Kiyoshi YASUKAWA, Kuniyo INOUYE
    2011 Volume 75 Issue 8 Pages 1564-1569
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Green tea catechins inhibit human matrix metalloproteinase 7 (MMP-7) activity non-competitively, and the galloyl group is essential for potent inhibition (Oneda et al., J. Biochem., 133, 571–576 (2003)). In this study, we analyzed the mechanism of this inhibition. In the hydrolysis of (7-methoxycoumarin-4-yl)acetyl-L-Pro-L-Leu-Gly-L-Leu-[N3-(2,4-dinitrophenyl)-L-2,3-diaminopropionyl]-L-Ala-L-Arg-NH2, the inhibitory effects of (−)-epigallocatechin-3-gallate (EGCG), (−)-gallocatechin-3-gallate (GCG), (−)-epicatechin-3-gallate (ECG), and (−)-catechin-3-gallate (CG) increased with increasing pH levels from 7.0 to 8.5. The inhibitory effects of EGCG and GCG were more potent than those of ECG and CG, and increased with increasing CaCl2 concentrations from 10 to 50 mM. The fluorescence of EGCG and GCG decreased with increasing CaCl2 concentrations and with the addition of MMP-7, while those of ECG and CG did not. Our results suggest that these differences result from that in the B ring, EGCG and GCG have phenol hydroxyl groups at the 3′, 4′, and 5′ positions, while ECG and CG have them at the 3′ and 4′ positions.
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  • Chiyomi NISHIDA, Takeo TOMITA, Makoto NISHIYAMA, Ryuyo SUZUKI, Mutsuko ...
    2011 Volume 75 Issue 8 Pages 1570-1575
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    A/B-Transferase is a glycosyltransferase that transfers a sugar substrate onto H-antigen, which is responsible for the synthesis of glycoprotein- and glycolipid-conjugates termed A/B-antigens. One polymorphism that causes the Pro234Ser substitution in B-transferase was recently found in a genotyping study, and might be cis-AB. In the present study, we analyzed the phenotypes arising from the enzymatic specificity of B-transferase with the Pro234Ser mutation. To evaluate the effect of the P234S mutation on enzymatic specificity, we generated an expression plasmid for B-transferase with Pro234Ser as well as A-transferase with Leu266Met, which is frequently found in cis-ABs. Transfection of B-transferase/P234S or A-transferase/L266M cDNA into HeLa cells, an O-blood group cell line, resulted in an AB-phenotype by absorption-elution testing and immunostaining, whereas A- and B-transferase-expressing HeLa cells exhibited only their own activity. Molecular simulation indicated that the P234S mutation causes a conformational change in the substrate pocket making it suitable for N-acetylgalactosamine.
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  • Lingzhu MENG, Ming LI, Seung Hwan YANG, Tae-Jong KIM, Joo-Won SUH
    2011 Volume 75 Issue 8 Pages 1576-1581
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    The addition of extracellular ATP (exATP) to four Streptomyces strains had similar effects: low exATP levels stimulated antibiotic production and high levels reduced it. Compared with antibiotic production, the concentrations of intracellular ATP (inATP) in the tested strains were opposite, which suggests a role of inATP in regulating secondary metabolite production. Under inactivation of the polyphosphate kinase gene (ppk) in Streptomyces lividans, we observed the same results: when the inATP level in the mutant strain was lower than in the parent strain, more antibiotic was produced. Combining all the results, a strong inverse relationship between [inATP] and the secondary metabolite production is suggested by this study.
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  • Tomoya SAKAMOTO, Yuko YAMAGUCHI, Tsuyoshi GOTO, Nobuyuki TAKAHASHI, Te ...
    2011 Volume 75 Issue 8 Pages 1582-1587
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    Monitoring of inflammation in adipose tissues, which causes insulin resistance, is valuable in evaluating insulin resistance. We developed an in vitro analysis system using a fluorescence protein (FP) as a reporter gene driven by pro-inflammatory cytokine promoters such as monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNFα). In the reporter-transfected RAW264 cells, the protein expression levels of green fluorescence protein (GFP) were increased by inflammatory stimulations such as lipopolysaccharide (LPS), conditioned medium prepared using hypertrophied 3T3-L1 adipocytes, and a co-culture system. The changes in fluorescence intensity were equivalent to those of the mRNA and protein expression levels for each cytokine. Moreover, the effects of 15-deoxy-12,14Δ-prostaglandine J2, a natural anti-inflammatory compound, were detectable in this system. These data indicate that the FP system developed here is an analysis system of low cost with simple procedures for evaluating inflammation, suggesting usability in the large-scale screening of anti-inflammatory compounds.
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  • Takumi CHINEN, Yu OTA, Yoko NAGUMO, Hiroshi MASUMOTO, Takeo USUI
    2011 Volume 75 Issue 8 Pages 1588-1593
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    Budding yeast is often used in chemical genetics for screening, target identification, and compound verification, but its high-level drug resistance has made the analysis of compounds difficult. Here we report the construction of 12geneΔ0HSR, a strain that lacks eight efflux pumps located on the plasma membrane and four transcription factors involved in expression of efflux pumps, and contains the RME1(ins-308A) mutation. This strain retained sufficient transformation, mating, and sporulation efficiency for genetic analysis in addition to hypersensitivity against several compounds. 12geneΔ0HSR is a useful tool for chemical biology, not only in chemical screening but in target identification and verification of bioactive compounds.
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Biochemistry & Molecular Biology Notes
Food & Nutrition Science Regular Papers
  • Kayoko KAWAKAMI, Saiko AKETA, Hiroki SAKAI, Yusuke WATANABE, Hiroshi N ...
    2011 Volume 75 Issue 8 Pages 1435-1439
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    The antihypertensive and vasorelaxant effects of water-soluble proanthocyanidins, extracted in persimmon leaf tea, were investigated in spontaneously hypertensive rats, rat aortas, and human umbilical vein endothelial cells. Oral administration of proanthocyanidins significantly decreased the systolic blood pressure of the rats after 4 h, as compared with distilled water controls. A vasorelaxant effect on rat aortas was induced by proanthocyanidins, and it was abolished by removal of the endothelium and inhibition of endothelial nitric oxide synthase and soluble guanylyl cyclase activity. The phosphorylation levels of endothelial nitric oxide synthase (Ser-1177) and the upstream kinase Akt (Ser-473) in umbilical cells also increased in a time-dependent manner after the addition of a proanthocyanidin-rich fraction. These results suggest that the antihypertensive effect of proanthocyanidins in persimmon leaf tea is due to vasorelaxation via an endothelium-dependent nitric oxide/cGMP pathway, and that proanthocyanidins might be useful in dietary lowering of blood pressure.
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  • Ik-Hyun CHO, Min Jung LEE, Jong-Hyun KIM, Na Young HAN, Kyu Won SHIN, ...
    2011 Volume 75 Issue 8 Pages 1440-1445
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
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    Supplementary material
    Fritillaria ussuriensis (FU, derived from the bulbs of various species of the genus Fritillaria, including Fritillaria thunbergii Miq.) is used in herbal medicine to treat conditions such as eczema, skin burns, and frostbite. In this study, we investigated the mechanism of the anti-allergy effect of FU. FU extract (80 mg/kg), orally administered to Sprague-Dawley (SD) rats, significantly inhibited the passive cutaneous anaphylaxis (PCA) reaction. It inhibited the compound 48/80-induced release of histamine from rat peritoneal mast cells in a concentration-dependent manner. Significant inhibitory effects of the FU extract on IL-6, IL-8, and TNF-α (1, 10, and 100 μg/mL) were observed in HMC-1 cells. Treatment with FU attenuated PMA plus A23187-induced phosphorylation of all three MAPKs, especially at concentrations of 10 and 100 μg/mL. Further, it (80 mg/kg) led to significant inhibition of mast-cell accumulation in ear tissue at the chronic phase. These results indicate that it inhibits allergic reactions.
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  • Jie XU, Yu-Ming WANG, Ting-Yu FENG, Bei ZHANG, Tatsuya SUGAWARA, Chang ...
    2011 Volume 75 Issue 8 Pages 1466-1471
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    Cerebrosides are a kind of important bioactive substance in sea cucumber. A novel cerebroside, AMC-2, was purified from the less-polar lipid fraction of the sea cucumber Acaudina molpadioides by repeated column chromatography. The major structure of AMC-2 was analyzed by gas chromatography-mass spectra. The amide-linked fatty acid unit was confirmed to be four saturated and monounsaturated α-hydroxy fatty acids, the long-chain base was dihydroxy sphingoid base with one double bond, and the glycosyl group was glucose. We also investigated the anti-fatty liver activity of AMC-2 in rats with fatty liver induced by orotic acid. AMC-2 significantly reduced hepatic triglyceride (TG) and total cholesterol (TC) levels at a diet supplement of 0.03% and 0.006%. The indexes of stearoyl-CoA desaturase (SCD) activity and mRNA expression were significantly decreased by AMC-2. This indicates that AMC-2 ameliorated nonalcoholic fatty liver disease (NAFLD) through suppression of SCD activity and impaired the biosynthesis of monounsaturated fatty acids in the livers of the rats.
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  • Hye Eun MOON, Md. Nurul ISLAM, Bo Ra AHN, Sabiha Sultana CHOWDHURY, He ...
    2011 Volume 75 Issue 8 Pages 1472-1480
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    The present work investigates protein tyrosine phosphatase 1B (PTP1B) and the α-glucosidase inhibitory activities of two edible brown algae, Ecklonia stolonifera and Eisenia bicyclis, as well as in their isolated phlorotannins. Since the individual extracts and fractions showed significant inhibitory activities, column chromatography was performed to isolate six phlorotannins, phloroglucinol (1), dioxinodehydroeckol (2), eckol (3), phlorofurofucoeckol-A (4), dieckol (5), and 7-phloroeckol (6). Phlorotannins 3–6 were potent and noncompetitive PTP1B inhibitors with IC50 values ranging from 0.56 to 2.64 μM; 4–6 exhibited the most potent α-glucosidase inhibition with IC50 values ranging from 1.37 to 6.13 μM. Interestingly, 4 and 6 were noncompetitive, while 5 exhibited competitive inhibition in an α-glucosidase assay. E. stolonifera and E. bicyclis as well as their isolated phlorotannins therefore possessed marked PTP1B and α-glucosidase inhibitory activities; this could lead to opportunities in the development of therapeutic agents to control the postprandial blood glucose level and thereby prevent diabetic complications.
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  • Toshiyuki NAKAMURA, Ryohei TANAKA, Hitoshi ASHIDA
    2011 Volume 75 Issue 8 Pages 1506-1510
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    β-Glucuronidase and sulfatase are the major deconjugating enzymes used in the cleavage of the glucuronate and sulfate moieties, respectively, from certain conjugated food factors including polyphenols. In the present study, we found that compounds having the same molecular weights as catechins were present in Helix pomatia- and/or Abalone entrails-derived β-glucuronidase and sulfatase by liquid chromatography tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring methods. On the other hand, the same molecular weights as catechins were undetectable in Escherichia coli-derived β-glucuronidase and Aerobacter aerogenes-derived sulfatase. By high performance liquid chromatography, enzyme-derived catechins were not detected because of approximately 1,000-fold lower sensitivity as compared to LC-MS/MS. These results suggest that the catechins in these enzymes might be attributed to the diets of the organisms as the enzyme sources.
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  • Ritsuro IDETA, Tomohiro SAKUTA, Yusuke NAKANO, Taro UCHIYAMA
    2011 Volume 75 Issue 8 Pages 1516-1523
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    Dietary glucosylceramide improves the skin barrier function. We used a microarray system to analyze the mRNA expression in SDS-treated dorsal skin of the hairless mouse to elucidate the molecular mechanisms involved. The transepidermal water loss of mouse skin was increased by the SDS treatment, this increase being significantly reduced by a prior oral administration of glucosylceramides. The microarray-evaluated mRNA expression ratio showed a statistically significant increase in the expression of genes related to the cornified envelope and tight junction formation when compared with all genes in the glucosylceramide-fed/SDS-treated mouse skin. We then examined the contribution of glucosylceramide metabolites to the tight junction formation of cultured keratinocytes. The SDS treatment of cultured keratinocytes significantly decreased the transepidermal electrical resistance, this decrease being significantly ameliorated in the presence of sphingosine or phytosphingosine, the major metabolites of glucosylceramide. These results suggest that an oral administration of glucosylceramide improved the skin barrier function by up-regulating genes associated with both the cornified envelope and tight junction formation.
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Food & Nutrition Science Notes
Food & Nutrition Science Communication
  • Ruiqing YAO, Akihito YASUOKA, Asuka KAMEI, Yoshinori KITAGAWA, Tomohir ...
    2011 Volume 75 Issue 8 Pages 1635-1637
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    The constitutive androstane receptor CAR is a xenosensing nuclear receptor that can be activated by natural polyphenols such as flavonoids and catechins. We examined alcoholic beverage phytochemicals for their ability to activate CAR. HepG2 cells were transfected with CAR expression vector and its reporter gene, and then treated with trans-resveratrol, ellagic acid, β-caryophyllene, myrcene, and xanthohumol. A luciferase assay revealed that ellagic acid and trans-resveratrol activated both human and mouse CAR. Since CAR regulates many genes involved in energy metabolism, the possibility exists that these polyphenols would reduce the risk of certain alcohol-induced metabolic disorders with the help of CAR.
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Microbiology & Fermentation Technology Regular Papers
  • Soichi FURUKAWA, Natsumi NOJIMA, Kanako YOSHIDA, Satoru HIRAYAMA, Hiro ...
    2011 Volume 75 Issue 8 Pages 1430-1434
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    Cells of Lactobacillus plantarum ML11-11, an isolate from Fukuyama pot vinegar, and the yeast Saccharomyces cerevisiae formed significant mixed-species biofilms with concurrent inter-species co-aggregation. The co-aggregation did not occur with heated or proteinase K-treated ML11-11 cells, or in the presence of D-mannose, suggesting that surface proteins of ML11-11 and mannose-containing surface substance(s) of yeast were the predominant contributing factors. Sugar fatty acid ester inhibited mixed-species biofilm formation, but did not inhibit co-aggregation, suggesting that the cell-cell adhesion and cell-polystylene adhesion are controlled by different mechanisms. Microscopic observation and microflora analysis revealed that inter-species co-aggregation plays an important role in the formation of the mixed-species biofilm.
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  • Sung-Yun HONG, Jee-Hwan OH, Inhyung LEE
    2011 Volume 75 Issue 8 Pages 1490-1495
    Published: August 23, 2011
    Released: August 23, 2011
    [Advance publication] Released: August 07, 2011
    JOURNALS FREE ACCESS
    To improve its bioavailability and pharmacological effects in humans, red ginseng was fermented with a newly isolated fungus, Monascus pilosus KMU103. Most of the ginsenosides were converted to deglycosylated ginsenocides, such as Rh1, Rh2, and Rg3. The total amount of ginsenosides Rh1, Rh2, and Rg3 was 838.7 mg/kg in the red ginseng, and increased to 4,117 mg/kg after 50 L fermentation in 13% red ginseng and 2% glucose. In addition, the Monascus-fermented red ginseng contained 3,089 mg/kg of monacolin K, one of the metabolites produced by Monascus known to reduce cholesterol in the blood. This newly developed Monascus-fermented red ginseng should result in improved health effects, not only by biotransforming gisenosides to deglycosylated ones but also by creating additional bioactive compounds.
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Microbiology & Fermentation Technology Notes
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