(Vol.63 No.5 1999)
Ryoko IWAMOTO, Chieko SAKAMOTO, Keiko TAMURA, Yuji MIKATA,
and Mieko TANAKADepartment of Chemistry, Faculty of Science, Nara Womens University, Nara 630-8506, Japan
Received August 11, 1998; Accepted January 4, 1999
D-Glucosaminitol dehydrogenase, which catalyzes the conversion of D-glucosaminitol to 3-keto-D-glucosaminitol, was purified to apparent homogeneity from extracts of Agrobacterium radiobacter. This organism has constitutively depressed levels of the enzyme but expression of the enzyme is induced by addition of D-glucosamine to the medium. Purification included ammonium sulfate fractionation and chromatography on columns of DEAE-Sephacel, Octyl-Sepharose CL-4B, and Cellulofine. The purified enzyme migrated as a single band, coinciding with dehydrogenase activities specific for D-glucosaminitol and ethanol, when electrophoresed on a 7.5 polyacrylamide gel at pH 8.0. Electrophoresis on a 12.5 PAGE in the presence of 1 SDS also yielded a single band. The enzyme had an apparent molecular mass of 79 kDa, as measured by the pattern of elution from a column of Cellulofine. The results indicated that the enzyme was a dimer of identical (or nearly identical) subunits of 39.5 kDa. D-Glucosaminitol dehydrogenase required NAD{ as a cofactor and used ethanol as the preferred substrate, as well as aliphatic alcohols with 2 to 4 carbon atoms, D-glucosaminitol, D-glucosaminate, DL-allothreonine, glycerol, and erythritol as additional substrates. In 50 mM Tris-HCl buffer (pH 9.0)||at 25C, the Km for D-glucosaminitol, ethanol, and NAD{||were 2.2, 2.0, and 0.08 mM, respectively. The enzyme had a pH optimum of 10 for D-glucosaminitol and 8.5 for ethanol. The enzyme lost substantial activity when treated||with pyrazole, with certain reagents that react with sul||||fhydryl groups and with Zn2{ ion. The various results||together suggest that the enzyme exploits different amino acid residues for the dehydrogenation of ethanol and of D-glucosaminitol.
D-glucosaminitol dehydrogenase; alcohol dehydrogenase; NAD{; Agrobacterium radiobacter
-2-
Characterization of yrpC Gene Product of Bacillus subtilis IFO 3336 as Glutamate
Racemase Isozyme
Makoto ASHIUCHI,1 Kenji SODA,2 and Haruo MISONO1E
1Research Institute of Molecular Genetics, Kochi University, Nankoku, Kochi 783-8502, Japan
2Faculty of Engineering, Kansai University, Suita, Osaka 564-0073, JapanReceived August, 11, 1998; Accepted January 6, 1999
Glr, the glutamate racemase of Bacillus subtilis (formerly Bacillus natto) IFO 3336 encoded by the glr gene, and YrpC, a protein encoded by the yrpC gene, which is located at a different locus from that of the glr gene in the B. subtilis genome, share a high sequence similarity. The yrpC gene complemented the D-glutamate auxotrophy of Escherichia coli WM335 cells defective in the glutamate racemase gene.||Glutamate racemase activity was found in the extracts of||||E. coli WM335 clone cells harboring a plasmid, pYRPC1,||||carrying its gene. Thus, the yrpC gene encodes an iso||||zyme of glutamate racemase of B. subtilis IFO 3336. YrpC is||||mostly found in an inactive inclusion body in E. coli||JM109/pYRPC1 cells. YrpC was solubilized readily, but glutamate racemase activity was only slightly restored. We purified YrpC from the extracts of E. coli JM109/pYRPC2 cells using a Glutathione S-transferase Gene Fusion System to characterize it. YrpC is a monomeric protein and contains no cofactors, like Glr. Enzymological properties of YrpC, such as the substrate specificity and optimum pH, are also similar to those of Glr. The thermostability of YrpC, however, is considerably lower than that of Glr. In addition, YrpC showed higher affinity and lower catalytic efficiency for L-glutamate than Glr. This is the first example showing the occurrence and properties of a glutamate racemase isozyme.
glutamate racemase; isozyme; Bacillus subtilis; characterization
-3-
Protective Effects of Dietary Nasunin on Paraquat-induced Oxidative Stress
in Rats
Yuriko KIMURA, Yumi ARAKI, Asako TAKENAKA, and Kiharu IGARASHI
Department of Bioresourse Engineering, Faculty of Agriculture, Yamagata University, 1-23 Wakaba-machi, Tsuruoka-shi, Yamagata 997-0037, Japan
Received September 2, 1998; Accepted January 22, 1999
The preventive effects of nasunin (delphinidin-3-[4-p-coumaroyl-rhamnosyl(16)glucoside]-5-glucoside) on paraquat-induced oxidative stress were determined in rats. Decreased food intake and body weight gain and increased lung weight by feeding the rats a diet containing paraquat were clearly suppressed by supplementing nasunin to the paraquat diet. Paraquat feeding increased the concentration of thiobarbituric acid-reactive substances (TBARS) in liver lipids and the atherogenic index, and decreased the liver triacylglycerol level. These effects were also suppressed by supplementing nasunin to the paraquat diet. In addition, catalase activity in the liver mitochondrial fraction was markedly decreased by feeding the paraquat diet, this decrease being partially suppressed by supplementing the paraquat diet with nasunin. These results suggest that nasunin acted preventively against the oxidative stress in vivo that may have been due to active oxygen species formed through the action of paraquat.
nasunin; oxidative stress; paraquat; anthocyanin
-4-
Production and Properties of the Linamarase and Amygdalase Activities
of Penicillium aurantiogriseum P35
Maurizio PETRUCCIOLI, Leon BRIMER,E Anna Rita CICALINI, Valentina PULCI,
and Federico FEDERICIEEDepartment of Agrobiology and Agrochemistry, University of Tuscia, Via S.C. De Lellis,
I-01100 Viterbo, ItalyReceived Spetember 17, 1998; Accepted December 14, 1998
The effects of medium composition on the production of -glucosidase (amygdalase and linamarase) by Penicillium aurantiogriseum P35 were studied and the medium optimized as follows (g/l of deionized water): pectin, 10.0; (NH4)2SO4, 8.0; KH2PO4, 8.0; Na2HPO4, 2.8; MgSO4E7H2O, 0.5; yeast extract, 4.0; initial pH 6.0. When grown in a bench fermenter on this medium, the fungus produced 50.5 mU of amygdalase and 9.4 mU of linamarase per ml of culture broth. Two -glucosidases (PGI and PGII), each having amygdalase and linamarase activities, were recovered from the culture broth and purified; their relative molecular weights, as native enzymes, were estimated to be about 247000 and 147000, respectively. Both enzymes showed the same optimum pH (6.0) but different optimum temperatures (55 and 60C for PGI and PGII, respectively). Thermostability (10 min at 60C) and half-life of enzyme activity (7 hours at 60C) of PGII were higher than those of PGI (10 min at 50C and 2 hours at 55C, respectively). A wide range of cyanogenic glycosides (such as tetraphyllin B, epivolkenin, gynocardin, passibiflorin, prunasin, taxiphyllin, amygdalin, lucumin, sambunigrin, dhurrin, linamarin and cardiospermin sulfate) were hydrolyzed by both enzymes.
Penicillium aurantiogriseum; linamarase; amygdalase; production; properties
-5-
Existence of Two Kinds of Sulfur-reducing Systems in Iron-oxidizing Bacterium
Thiobacillus ferrooxidans
Kim Yong NG, Sayuri INOUE, Akira FUJIOKA, Kazuo KAMIMURA, and Tsuyoshi SUGIOE
Department of Biological Function and Genetic Resources Science, Faculty of Agriculture, Okayama University,
1-1-1 Tsushima Naka, Okayama 700-8530, JapanReceived September 28, 1998; Accepted January 25, 1999
Intact cells of Thiobacillus ferrooxidans NASF-1 incubated under anaerobic conditions in a reaction mixture containing 0.5 colloidal sulfur produced hydrogen sulfide (H2S) extracellularly. The amount of H2S produced by cells increased corresponding to the cell amounts and colloidal sulfur. Two activity peaks of H2S production were observed at pH 1.5 and 7.5. We tentatively called the enzyme activities pH 1.5- and pH 7.5-sulfur reducing systems, respectively. Seven strains of T. ferrooxidans tested had both the activities of pH 1.5- and pH 7.5-sulfur reducing systems, but at different levels. T. ferrooxidans NASF-1 showed the highest activity of the pH 1.5-sulfur reducing system and strain 13598 from ATCC showed the highest activity of the pH 7.5-sulfur reducing system. Further characteristics of H2S production were studied with intact cells of NASF-1. The optimum temperatures for pH 1.5- and pH 7.5-sulfur reducing systems of NASF-1 were 40C. Hydrogen sulfide production continued for 8 days and total amounts of H2S produced at pH 7.5 and 1.5 were 832 and 620 nmol/mg protein, respectively. The pH 7.5-sulfur reducing system used only colloidal sulfur as the electron acceptor. However, the pH 1.5-sulfur reducing system used both colloidal sulfur and tetrathionate. Thiosulfate, dithionate, and sulfite could not be used as the electron acceptor for both of the sulfur reducing systems. Potassium cyanide activated by 3- fold the pH 1.5-sulfur reducing system activity at 0.5 mM but did not affect the activity of the pH 7.5-sulfur reducing system. An inhibitor of sulfite reductase, p-chloromercuribenzene sulfonic acid, did not affect either enzyme activity. Sodium molybdate and monoiodoacetic acid strongly inhibited the activity of the pH 1.5-sulfur reducing system at 1.0 mM, but not the activity of pH 7.5-sulfur reducing system.
iron-oxidizing bacterium; Thiobacillus ferrooxidans; hydrogen sulfide; sulfur reduction
-6-
Molecular Cloning and Expression of the Gene Encoding a Phospholipase A1
from Aspergillus oryzae
Ichiro WATANABE, Ryuta KOISHI, Yoshio YAO, Toshiaki TSUJI,
and Nobufusa SERIZAWA,EBiomedical Research Laboratories, Sankyo Co., Ltd., 1-2-58, Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan
Manufacturing Section 2, Hiratsuka Factory, Sankyo Co., Ltd., 173, Kamijuku, Nakahara, Hiratsuka-shi, Kanagawa 254-0071, JapanRecieved October 5, 1998; Accepted December 25, 1998
Phospholipase A1 (PLA1) is a hydrolytic enzyme that catalyzes removal of the acyl group from position 1 of lecithin to form lysolecithin. The genomic DNA and cDNA encoding PLA1 from Aspergillus oryzae were cloned with the mixed deoxyribonucleotide-primed polymerase chain reaction. The PLA1 gene is composed of 1,056 bp and has four exons and three short introns (63, 54, and 51 bp). The deduced amino acid sequence of PLA1 contained the N-terminal sequence of the mature PLA1 analyzed by Edman degradation. PLA1 cDNA has an open reading frame of 885 bp encoding the PLA1 precursor of 295 amino acid residues. The mature PLA1 is composed of 269 amino acid residues, and a prepro-sequence of 26 amino acid residues is at the N-terminal region of the PLA1 precursor. PLA1 has two possible N-glycosylation sites (Asn27 and Asn55). PLA1 has a consensus pentapeptide (-Gly-His-Ser-Xaa-Gly-), which is conserved in lipases. The amino acid sequence of PLA1 showed 47 identity with that of mono- and diacylglycerol lipase from Penicillium camembertii. The PLA1 cDNA was expressed in Saccharomyces cerevisiae KS58-2D, indicating the cloned gene to be functional.
phospholipase A1; Aspergillus oryzae; lysolecithin; CPY; Saccharomyces cerevisiae KS58-2D
-7-
The Phylogeny of the Cactophilic Yeasts Based on the 18S Ribosomal RNA Gene
Sequences: The Proposals of Phaffomyces antillensis and Starmera caribaea, New
Combinations
Yuzo YAMADA, Hiroko KAWASAKI, Yuka NAGATSUKA, Kozaburo MIKATA,
and Tatsuji SEKIThe International Center for Biotechnology, Osaka University, 2-1 Yamadaoka, Suita, Osaka 568-0871, Japan
Laboratory of Applied Microbiology, Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan
Institute for Fermentation, 2-17-85 Juso-honmachi, Yodogawa-ku, Osaka 532-8686, JapanReceived October 12, 1998; Accepted December 18, 1998
The complete sequences of the 18S rRNA gene fragments of the type strains of the cactophilic yeast species, Pichia antillensis, Pichia caribaea, Phaffomyces opuntiae, Phaffomyces thermotolerans, Starmera amethionina var. amethionina, and Starmera amethionina var. pachycereana were determined and compared. The type strain of Phaffomyces opuntiae had two kinds of the 18S rRNA gene sequences of which base differences were counted to be 15 and of which the percent similarity was calculated to be 99.1. The type strains of P. antillensis, P. caribaea, and Starmera amethionina var. pachycereana had the Q-7 system. The phylogenetic analyses showed that the genera Phaffomyces and Starmera were monophyletic and distant from each other and from the other species examined of the ascogenous teleomorphic genera, and that P. antillensis and P. caribaea were included within the clusters of the genera Phaffomyces and Starmera, respectively. The two Pichia species were transferred to the genera Phaffomyces and Starmera as the new combinations, Phaffomyces antillensis and Starmera caribaea. The new family Phaffomycetaceae was proposed as the type genus Phaffomyces.
Phaffomyces antillensis comb. nov.; Starmera caribaea comb. nov.; Phaffomycetaceae fam. nov.; phylogeny
-8-
Modification of Chitosan to Improve Its Hypocholesterolemic Capacity
Jung Kul LEE, Soo Un KIM, and Jung Hoe KIME
Department of Biological Sciences, Korea Advanced Institute of Science and Technology,
Taejon 305-701, Korea
Department of Agricultural Chemistry and Research Center for New Biomaterials in Agriculture,
Seoul National University, Suwon 441-744, KoreaReceived October 20, 1998; Accepted January 22, 1999
Cholestyramine is the most widely used bile acid sequestrant in the treatment of hypercholesterolemia. However, cholestyramine has unpleasant side effects as a consequence of its hydrophobic backbone. Therefore, high-capacity bile acid sequestering biopolymers with cationic chitosan derivatives were developed, because electrostatic interactions are important for binding with bile acid anions. Dialkylaminoalkylation and reductive amination of chitosan were done to add dialkylaminoalkyl and an additional free amino group at a hydroxyl site in the chitosan backbone respectively and the aminoderivatized chitosan derivatives were quaternized with methyl iodide to produce a cationic polyelectrolyte. The in vitro bile acid binding capacity of the chitosan derivatives in aqueous NaCl was measured by reversed-phase HPLC. The binding capacities of sodium glycocholate (a major bile acid) to chitosan, DEAE-chitosan, quaternized DEAE-chitosan, and cholestyramine were 1.42, 3.12, 4.06, and 2.78 mmol/g resin, respectively. With quaternized DEAE-chitosan, the bile acid binding capacity increased ~50 over that of cholestyramine. The bile acid binding capacity of dialkylaminoalkyl chitosan derivatives increased with the number of carbons in the alkyl groups, indicating that hydrophobic interaction is a secondary factor for the sequestration of bile acids.
chitosan; amination; bile acid sequestrant; electrostatic interaction; hydrophobic interaction
-9-
Structure-activity Relationship for the Insect Antifeedant Activity
of Benzofuran Derivatives
Masanori MORIMOTO, Masamitsu URAKAWA, Tatsuo FUJITAKA, and Koichiro KOMAI
Department of Agricultural Chemistry, Faculty of Agriculture, Kinki University,
Nakamachi, Nara 631-8505, JapanReceived Octorber 20, 1998; Accepted January 27, 1999
Coumaran (2,3-dihydrobenzofuran), a secondary metabolite of Cyperus nipponicus, inhibits the feeding of polyphagous insects. This secondary metabolite is regarded as one of the defensive systems of the Cyperaceae. A number of naturally occurring benzofurans that differ in their substitution pattern and oxidation state have been investigated for their ability to inhibit insect feeding by a bioassay with the common cutworm (Spodoptera litura F. Noctuidae) that applies the leaf disk method. The evaluation of the antifeedant activity of each test compound used the ED50 value based on the dose-response curve that was calculated with the probit method. The 2,3-dihydrobenzofuran derivative, 7-acetyl-4,6-dimethoxy-2-isopropenyl-2,3-dihydrobenzofuran, had an ED50 value of 1.3 g (5.4~10|9 mol)/cm2 against the common cutworm. The introduction of methoxy and acetyl groups increased the insect antifeedant activity. Furthermore, the insect antifeedant activity increased with decreasing lipophilicity of the test compounds.
insect antifeedant; 2,3-dihydrobenzofuran; structure-activity relationship; Spodoptera litura
-10-
Construction of an Effective Host-Vector System for the Yeast
Saccharomyces exiguus Yp74L-3
Taisuke HISATOMI,E Kazutaka TAKAHASHI, Tetsuya OOMOTO, Yasunori YAMASHITA,
Shu-ichi HASEGAWA, and Michio TSUBOIDepartment of Biotechnology, Faculty of Engineering, Fukuyama University, Gakuen-cho,
Fukuyama, Hiroshima 729-0292, JapanReceived October 22, 1998; Accepted December 25, 1998
An effective host-vector system specific to the yeast Saccharomyces exiguus Yp74L-3 was constructed to promote the molecular genetic analyses for the yeast. To obtain a stable reversionless host strain, we constructed an S. exiguus strain carrying leu2::ScURA3 by disrupting the S. exiguus LEU2 gene with the S. cerevisiae URA3 gene. A vector plasmid unique to S. exiguus was subsequently developed by inserting both the LEU2 gene and an ARS cloned from S. exiguus into an Escherichia coli phagemid, pUC119. The vector constructed, pTH119 was able to transform the S. exiguus leu2::ScURA3 strain to Leu{ efficiently. The stability of the vector in the S. exiguus host cells resembled that of a YRp-type vector in S. cerevisiae.
Saccharomyces exiguus; LEU2 gene; autonomously replicating sequence (ARS); host-vector system; Saccharomyces cerevisiae
-11-
Formation Mechanism for Potent Antioxidative o-Dihydroxyisoflavones in
Soybeans Fermented with Aspergillus saitoi
Hideo ESAKI,E Ryoko WATANABE, Hiromichi ONOZAKI, Shunro KAWAKISHI,
and Toshihiko OSAWADepartment of Food and Nutrition, Sugiyama Jogakuen University, 17-3 Hoshigaoka-motomachi,
Chikusa-ku, Nagoya 464-8662, Japan
Department of Applied Biological Sciences, Nagoya University, Nagoya 464-8601, JapanReceived October 29, 1998; Accepted January 27, 1999
The formation mechanism for the potent antioxidative o-dihydroxyisoflavones, 8-hydroxydaidzein (8-OHD) and 8-hydroxygenistein (8-OHG), was studied by incubating whole soybeans in a solid culture and a soybean extract in a liquid culture with Aspergillus saitoi.
Analyses of changes in the isoflavone analogue content, -glucosidase activity, and isoflavone hydroxylation ability indicated that 8-OHD and 8-OHG were formed from daidzein and genistein, respectively, by microbial hydroxylation, being respectively liberated from daidzin and genistin by -glucosidase from A. saitoi during incubation. No selective hydroxylation reaction at the 8-position of daidzein and genistein were apparent during the vegetative stage, but were induced at the stage of sporulation.
antioxidant; 8-hydroxydaidzein; 8-hydroxygenistein; Aspergillus saitoi; sporulation
-12-
Cloning of a Gene Encoding Hydroxyquinol 1,2-Dioxygenase that Catalyzes
Both Intradiol and Extradiol Ring Cleavage of Catechol
Shuichiro MURAKAMI, Takao OKUNO, Eitaro MATSUMURA, Shinji TAKENAKA,
Ryu SHINKE, and Kenji AOKIEDepartment of Biofunctional Chemistry, Faculty of Agriculture, Kobe University, Rokko, Kobe 657-8501, Japan
Received October 29, 1998; Accepted January 13, 1999
Two Escherichia coli transformants with catechol 1,2-dioxygenase activity were selected from a gene library of the benzamide-assimilating bacterium Arthrobacter species strain BA-5-17, which produces four catechol 1,2-dioxygenase isozymes. A DNA fragment isolated from one transformant contained a complete open reading frame (ORF). The deduced amino acid sequence of the ORF shared high identity with hydroxyquinol 1,2-dioxygenase. An enzyme expressed by the ORF was purified to homogeneity and characterized. When hydroxyquinol was used as a substrate, the purified enzyme showed 6.8-fold activity of that for catechol. On the basis of the sequence identity and substrate specificity of the enzyme, we concluded that the ORF encoded hydroxyquinol 1,2-dioxygenase. When catechol was used as a substrate, cis,cis-muconic acid and 2-hydroxymuconic 6-semialdehyde, which were products by the intradiol and extradiol ring cleavage activities, respectively, were produced. These results showed that the hydroxyquinol 1,2-dioxygenase reported here was a novel dioxygenase that catalyzed both the intradiol and extradiol cleavage of catechol.
benzamide-assimilating bacterium; catechol 1,2-dioxygenase; extradiol ring cleavage; hydroxyquinol 1,2-dioxygenase; intradiol ring cleavage
-13-
Autoxidation of Linoleic Acid Encapsulated with Polysaccharides
of Differing Weight Ratio
Yasumasa MINEMOTO, Shuji ADACHI,E and Ryuichi MATSUNO
Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University,
Sakyo-ku, Kyoto 606-8502, JapanReceived November 6, 1998; Accepted January 29, 1999
Linoleic acid was encapsulated with pullulan, maltodextrin and gum arabic at various weight ratios of the fatty acid to wall material by the hot-air-drying method. The autoxidative process of the encapsulated linoleic acids was observed at 37C and at a relative humidity of 75. The weight ratio strongly affected the autoxidative process, autoxidation being more suppressed with smaller ratios. The autoxidation process of encapsulated linoleic acid leveled off at fraction Y of the unoxidized substrate within 15 days. The Y value strongly depended on both the ratio and the wall material, and steeply decreased near the ratio of 0.75 for every wall material. The dependence of the Y value on the weight ratio was analyzed by the two- and three-dimensional models for percolation theory. The two-dimensional model expressed well the experimentally observed dependence.
autoxidation; linoleic acid; encapsulation; percolation theory
-14-
Production of Biodegradable Polyester by a Transgenic Tobacco
Hideo NAKASHITA, Yuko ARAI,E Keiko YOSHIOKA, Toshiaki FUKUI, Yoshiharu DOI, Ron USAMI,E
Kohki HORIKOSHI,E and Isamu YAMAGUCHIThe Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
EToyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585, JapanReceived November 10, 1998; Accepted January 4, 1999
The acetoacetyl-CoA reductase gene (phbB) of Ralstonia eutropha and the poly[(R)-(|)-3-hydroxyalkanoate] synthase gene (phaCAC) of Aeromonas caviae were introduced into tobacco plant by Agrobacterium mediated transformation method. The resulting transgenic tobacco expressed both introduced genes and the expression of these genes was confirmed by enzymatic analysis and western blotting. GC-MS analysis of the chloroform extract of tobacco leaves indicated that the transgenic plant produced biodegradable polyester, poly-[(R)-(|)-3-hydroxybutyrate]. GPC analysis indicated that the number-average molecular weights (EEEMnE) and polydispersity (EEEMwE/EEEMnE) were 32,000 and 1.90, respectively.
transgenic plant; polyhydroxybutyrate; PHA; Aeromonas caviae; Agrobacterium
-15-
Potassium/Proton Antiport System Is Dispensable for Growth
of Enterococcus hirae at Low pH
Yoshimi KAKINUMA,E Kyoko YASUMURA, and Kazuei IGARASHI
Faculty of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
Received November 25, 1998; Accepted December 25, 1998
An energy-dependent K{/H{ antiport system is found in Enterococcus hirae ATCC 9790 cultured in a standard complex medium (Y. Kakinuma, and K. Igarashi, J. Biol. Chem. 263:14166-14170, 1988). We have now found that the activity of this antiport system was totally missing in cells cultured in a defined medium. In this defined medium, E. hirae did not grow well at pH near 9, but grew normally at pH below 7.5. This antiport system is important at high pH but dispensable at lower pH for ion homeostasis of this bacterium.
K{/H{ antiporter; ion homeostasis; Enterococcus hirae
-16-
Fatty Acids and Their Derivatives as Modulators of Appressorium Formation
in Magnaporthe grisea
Frank EILBERT,1 Eckhard THINES,1, Olov STERNER2 and Heidrun ANKE1,E
1LB Biotechnology, University of Kaiserslautern, Paul-Ehrlich-Str. 23, D-67663 Kaiserslautern, Germany
2Department of Organic Chemistry 2, Lund University, P.O. Box 124, S-21100 Lund, SwedenReceived November 25, 1998; Accepted January 7, 1999
Appressorium formation in germinating conidia of Magnaporthe grisea was inhibited on inductive and on noninductive surfaces by monounsaturated fatty acids with chain lengths of 16, 18, or 20 carbon atoms. On a noninductive surface, the inhibition was only observed upon stimulation with 1,16-hexadecanediol or oleyl alcohol, but not upon stimulation with 8-(4-chlorophenylthio)-adenosine-3,5-monophosphate. In the C18-series, fatty acids with a double bond in position 9 were the most active ones. At 1 g/ml of oleic or elaidic acid, less than 30 of the germinated conidia formed appressoria. The mode of inhibition was competitive to the inducing agent. On an inductive surface, compared to a noninductive surface the concentrations of oleic and elaidic acid needed for inhibition of appressorium formation were one order of magnitude higher. Methyl esters of inhibitory fatty acids and acids with two double bonds were not active. Like oleyl alcohol, elaidyl alcohol and petroselinyl alcohol stimulated infection structure formation on the noninductive surface.
Magnaporthe grisea; appressorium formation; fatty acid; signal transduction
-17-
Assembly of Staphylococcus aureus Leukocidin into a Pore-Forming Ring-Shaped
Oligomer on Human Polymorphonuclear Leukocytes and Rabbit Erythrocytes
Noriko SUGAWARA,1 Toshio TOMITA,1 Tsuruji SATO,2 and Yoshiyuki KAMIO1,
1Laboratory of Applied Microbiology and 2Division of Electron Microscopy, Graduate School
of Agricultural Science, Tohoku University, Aoba-ku, Sendai 981-8555, JapanReceived November, 30, 1998; Accepted January 6, 1999
Staphylococcal leukocidin consists of two separate proteins, LukS and LukF, which cooperatively lyse human and rabbit polymorphonuclear leukocytes and rabbit erythrocytes. Here we studied the pore-forming properties of leukocidin and the molecular architecture of the leukocidin pore. (1) Leukocidin caused an efflux of potassium ions from rabbit erythrocytes and swelling of the cells before hemolysis. However, ultimate lysis of the toxin-treated swollen erythrocytes did not occur when polyethylene glycols with hydrodynamic diameters of E2.1 nm were present in the extracellular space. (2) Electron microscopy showed the presence of a ring-shaped structure with outer and inner diameters of 9 and 3 nm, respectively, on leukocidin-treated human polymorphonuclear leukocytes and rabbit erythrocytes. (3) Ring-shaped structures of the same dimensions were isolated from the target cells, and they contained LukS and LukF in a molar ratio of 1:1. (4) A single ring-shaped toxin complex had a molecular size of 205 kDa. These results indicated that LukS and LukF assemble into a ring-shaped oligomer of approximately 200 kDa on the target cells, forming a membrane pore with a functional diameter of approximately 2 nm.
leukocidin; membrane pore; ring-shaped structure; human polymorphonuclear leukocyte; rabbit erythrocyte
-18-
A Competitive Enzyme-Linked Immunosorbent Assay-like Method
for the Measurement of Urinary Hyaluronan
Hiroshi MAEDA, Hiroshi FUJITA, Yoshiyuki SAKURA, Kyosuke MIYAZAKI,
and Makoto GOTOCenter for Glycosaminoglycan Analysis, Seikagaku Kogyo Co., 7-3-1 Kurihama, Yokosuka,
Kanagawa 239-0831, Japan
Department of Rheumatology, Tokyo Metropolitan Otsuka Hospital, 2-8-1 Minami-Otsuka,
Toshima-ku, Tokyo 170-0005, JapanReceived December 1, 1998; Accepted January 26, 1999
A highly sensitive method for measurement of urinary hyaluronan with a minimum molecular mass of 2,000 Da was developed without using HPLC or radioisotopes. This competitive enzyme-linked immunosorbent assay-like method, used competitive binding of free hyaluronan in the sample and biotin-labeled standard hyaluronan to hyaluronan binding protein in solid phase. A total of 150 healthy individuals from both sexes at ages from 0 to 100 years was examined by the established method. Hyaluronan of 384}80 ng/mg creatinine (mean}SD) was constantly excreted into urine of 24--40-year-old healthy adults. The urinary hyaluronan levels were significantly higher before age 1 (p<0.001) and rather high after 90 years compared to the other groups. The average molecular weight of urinary hyaluronan (5,500 Da) was constant through all generations. Sex difference of urinary hyaluronan was not observed both quantitatively or qualitatively.
hyaluronan; hyaluronan binding protein; urine; competitive enzyme-linked immunosorbent assay
-19-
Antiproliferative Activity of Flavonoids on Several Cancer Cell Lines
Satoru KAWAII, Yasuhiko TOMONO, Eriko KATASE, Kazunori OGAWA,
and Masamichi YANOENational Institute of Fruit Tree Science, Okitsu, Shimizu, Shizuoka 424-0204, Japan
Received December 8, 1998; Accepted January 19, 1999
||Twenty-seven Citrus flavonoids were examined for their||antiproliferative activities against several tumor and normal human cell lines. As a result, 7 flavonoids were judged to be active against the tumor cell lines, while they had weak antiproliferative activity against the normal human||cell lines. The rank order of potency was luteolin, nat||||sudaidain, quercetin, tangeretin, eriodictyol, nobiletin, and||3,3,4,5,6,7,8-heptamethoxyflavone. The structure-activity relationship established from comparison among these flavones and flavanones showed that the ortho-catechol moiety in ring B and a C2-C3 double bond were important for the antiproliferative activity. As to polymethoxylated flavones, C-3 hydroxyl and C-8 methoxyl groups were essential for high activity.
antiproliferative activity; flavonoids; cancer cell lines; human umbilical vein endothelial cells; human foreskin keratinocytes
-20-
Increased Production of Lactonizing Lipase (LipL) from Pseudomonas
sp. strain 109 by Lipids and Detergents
Junko TANAKA,1 Towa SUDO,1 Fumio IHARA,2 Takuya NIHIRA,1,E
and Yasuhiro YAMADA11Department of Biotechnology, Graduate School of Engineering, Osaka University,
2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
2Department of Plant Protection, National Institute of Fruit Tree Science, 2-1 Fujimoto,
Tsukuba, Ibaraki 305-8605, JapanReceived December 9, 1998; Accepted January 23, 1999
LipL of Pseudomonas sp. strain 109 is a unique lipase capable of catalyzing macrocyclic lactone synthesis using -hydroxyfatty acid esters as substrates. Several fatty acid esters were tested as inducers of LipL production. The addition of either soybean oil or a non-ionic detergent (Noigen HC) resulted in a 44 to 45-fold increase in extracellular LipL, and the presence of both resulted in a further 56-fold increase. Among the triglycerides tested, triolein was the most effective, with a 50-fold increase in LipL production. A Northern blot hybridization analysis found that the lipL transcript increased in the presence of soybean oil or Noigen HC, indicating that the production of LipL is regulated at the transcriptional level.
Pseudomonas; lipase; induction; transcription; regulation
-21-
Enhancing Effect of Dietary Vinegar on the Intestinal Absorption of Calcium
in Ovariectomized Rats
Mikiya KISHI,E Masahiro FUKAYA, Yoshinori TSUKAMOTO, Takashi NAGASAWA,
Kazushige TAKEHANA, and Naoyuki NISHIZAWACentral Research Institute, Mitsukan Group Co. Ltd., Aichi 475-8585, Japan
Department of Bioscience and Technology, Faculty of Agriculture, Iwate University, Iwate 020-8550, Japan
Department of Veterinary Anatomy, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, JapanReceived December 10, 1998; Accepted January 21, 1999
We studied the effect of dietary vinegar on calcium absorption by using ovariectomized rats fed on a low-calcium diet. The apparent absorption of calcium was higher when the rats were fed on a diet containing 1.6 vinegar for 32 days than when fed on a diet without vinegar (P<0.05). The calcium content in the femur of the rats given diets containing 0.4 and 1.6 vinegar were also higher (P<0.05). The serum parathyroid hormone level was lower and the crypt depth of the duodenum thicker in the rats fed on a diet containing 1.6 vinegar (P<0.05). These results suggest that dietary vinegar enhanced intestinal calcium absorption by improving calcium solubility and by the trophic effect of the acetic acid contained in vinegar, which would reduce the bone turnover caused by ovariectomy and be helpful in preventing osteoporosis.
calcium; vinegar; intestinal absorption; bone; rats
-22-
Localization of Sequential Antigenic Determinants on Bovine -Casein
with Synthetic Peptides and Antisera from Mouse, Rabbit, and Goat
Koko MIZUMACHI, Jun-ichi KURISAKI,E and Shuichi KAMINOGAWA
Department of Animal Products, National Institute of Animal Industry, Tsukuba Norin-kenkyu-danchi
P.O. Box 5, Ibaraki 305-0901, Japan
Department of Applied Biological Chemistry, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, JapanReceived December 16, 1998; Accepted January 20, 1999
The antigenic determinants of bovine -casein (-CN) were localized by using twenty overlapping peptides encompassing the entire sequence of -CN and anti--CN antisera from outbred mouse, rabbit and goat. The profile of the reactions was characteristic to the species, the dominant antigenic regions being 80--95, 143--158 and 195--209 in mouse, 1--16 in rabbit and 100--115 in goat. Regions 1--16, 100--115, 121--136 and 143--158 were antigenic in all three species. The number of antigenic regions recognized by goat was much fewer than that by mouse and rabbit, possibly because of the homology between bovine and goat -CN. A mixture of the twenty peptides could absorb about 50--60 of -CN specific antibodies from each species. Furthermore, the mouse and rabbit anti--CN antibodies were also specific to the phosphorylated regions. We therefore conclude that the major antigenic determinants on -CN would be largely sequential and include the phosphorylated sites.
-casein; synthetic peptide; antigenic determinants; milk allergy
-23-
Two Isoforms of a Human Actin-Related Protein Show Nuclear Localization
and Mutually Selective Expression between Brain and Other Tissues
Masahiko HARATA,E Ryo MOCHIZUKI, and Shigeki MIZUNO
Laboratory of Molecular Biology, Department of Molecular and Cell Biology, Division of Life Science,
Graduate School of Agricultural Science, Tohoku University, Tsutsumidori-Amamiyamachi 1-1, Aoba-ku,
Sendai 981-8555, JapanReceived December 17, 1998; Accepted January 20, 1999
Actin-related proteins (Arps), which are divergent, but apparently homologues to actin, are categorized into 10 classes. While Arps belonging to classes 1--3 were found to be localized in the cytoplasm across eukaryotic phyla, other classes of Arps were found mostly in invertebrates and suggested to contribute to structural modulation of chromatin. Here we report the identification and the characterization of two human isoforms of an Arp not belonging to classes 1--3, which we designated hArpN and hArpN. Both proteins were expressed in HeLa cells and they were found localized within the nucleus. Most interestingly, in different human tissues, hArpN and were found to be expressed mutually exclusively, and the expression of hArpN was absolutely restricted to the brain. These findings suggest that, in vertebrates, members of distantly related Arps might have tissue-specific functions in the nucleus, possibly through structural modulation of chromatin.
actin-related protein; chromatin structure; chromatin remodeling; tissue-specific expression
-24-
Four Novel Taxane Diterpenoids from the Needles of Japanese Yew,
Taxus cuspidata
Qing-Wen SHI, Takayuki ORITANI,E Tohru HORIGUCHI, Takeyoshi SUGIYAMA, Ryo MURAKAMI,
and Teiko YAMADALaboratory of Applied Bioorganic Chemistry, Division of Life Science, Graduate School of Agricultural Science,
Tohoku University, 1-1 Tsutsumidori-Amamiya, Aoba-ku, Sendai 981-8555, JapanReceived December 17, 1998; Accepted February 1, 1999
Four novel taxane diterpenes were isolated from the needles of the Japanese yew, Taxus cuspidata. Their structures||were established as 1-hydroxy taxuspine C, 2,7,9,||||10,13 - pentaacetoxy - 5 - cinnamoyloxy - 4,20 - epoxy-||||taxa-11-en-1-ol, 2,9,10,13-tetraacetoxy-taxa-4(20),||||11-dien-5-ol and 10-deacetyl taxinine on the basis of||spectral analyses.
Taxus cuspidata; Taxaceae; taxoid diterpenes; needles
-25-
Note
Cell Layer-Specific Accumulation of Anthocyanins in Response
to Gibberellic Acid in Tepals of Hyacinthus orientalis
Keizo HOSOKAWA
Tsukuba Medicinal Plant Research Station, National Institute of Health Sciences, 1 Hachimandai,
Tsukuba, Ibaraki 305-0843, JapanReceived July 24, 1998; Accepted January 6, 1999
Anthocyanin-producing cells in the tepals of flower buds of Hyacinthus orientalis were investigated. In field-grown flowers, anthocyanins were only produced in L2 cells (cells in the sub-epidermis) of tepals. However, when early-stage flower buds were cultured on medium containing GA3, anthocyanins were produced not only in L2 cells but also in L1 cells (cells in the epidermal layer) of tepals. The same anthocyanins were produced in tepals of both field-grown flowers and flower buds cultured in vitro.
anthocyanin; anthocyanin-producing cells; gibberellic acid; Hyacinthus orientalis
-26-
Note
Isolation of an Antioxidative Substance Produced by Aspergillus repens
Ryuta YAGI and Mikiharu DOIE
Marutomo Co., Ltd., 1696 Kominato, Iyo, Ehime 799-3192, Japan
Received October 28, 1998; Accepted January 14, 1999
The acidic fraction of an extract of the culture liquid of Aspergillus repens MA0197 showed strong antioxidative activity when tested by the ferric thiocyanate and TBA methods. Chromatographic purification of this acidic fraction gave an active substance identified as Neoechinulin A. This compound showed higher antioxidative activity than -tocopherol and could be expected to act as an antioxidant in Katsuobushi.
Katsuobushi; Aspergillus repens; molding; antioxidation; Neoechinulin A
-27-
Note
Multi-enzymatic Glucosylation Using Eucalyptus UDP-Glucosyltransferase
Coupled UDPglucose-Fermentation by Bakers Yeast
Nobuyoshi NAKAJIMA,1,E Kohji ISHIHARA,2 Hiroki HAMADA,3 Shin-ya YAMANE,3
Kaoru NAKAMURA,4 and Tsutomu FURUYA31Department of Nutritional Science, Okayama Prefectural University, Soja, Okayama 719-1112, Japan
2Department of Chemistry, Kyoto University of Education, Fushimi-ku, Kyoto 612-8522, Japan
3Department of Applied Science, Okayama University of Science, Ridai-cho, Okayama 700-0005, Japan
4Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, JapanReceived October 30, 1998; Accepted January 13, 1999
The enzymatic synthesis of glucoside compounds using a membrane-associated UDP-glucosyltransferase fraction from Eucalyptus perriniana cultured cells as a water-insoluble catalyst (N. Nakajima, et. al., J. Ferment. Bioeng., 84 (5), pp. 455--460, 1997) has been effectively done by coupling UDPglucose-fermentation by bakers yeast. For example, -thujaplicin (hinokitiol) and p-aminobenzoic acid were converted respectively to their corresponding -D-monoglucosides with the conversion rate of around 24--26 by the multi-enzymatic system with UDPglucose as a glucose donor, which is produced by yeast cells from glucose and 5-UMP. Addition of either cellobiose, a substrate of -glucosidase, or DL-1,2-anhydro-myo-inositol, an inhibitor for the enzyme in the reaction mixture, could increased the yield of these -D-monoglucosides. This new enzymatic system could also be used for the synthesis of flavonoid glucosides such as isoquercitrin (quercetin 3--O---D-glucoside).
UDP-glucosyltransferase; glucosylation; Eucalyptus perriniana; UDPglucose-fermentation; bakers yeast
-28-
Note
Inhibition of the Acid Lipase Activity by Apolipoprotein A-I in the Presence
of Lysosomal Proteases
Yuichi INOUE,E Takeshi OSE, Satoru MUKAI, Shunji EHIRA, Masami YONEKURA,
De-Xing HOU, and Makoto FUJIIDepartment of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University,
1-21-24 Korimoto, Kagoshima 890-0065, Japan
Faculty of Agriculture, Ibaraki University, 3-21-1, Amimachi-chuo, Inashiki-gun, Ibaraki 300-0332, JapanReceived November 2, 1998; Accepted December 29, 1998
It was found that the inhibition of the lysosomal acid lipase activity by rat apolipoprotein A-I (apo A-I) was increased with the degradation of apo A-I by the lysosomal proteases. We demonstrated that apo A-I could effectively inhibit the acid lipase activity even in the presence of the lysosomal proteases using the hepatic lysosomal fraction.
apolipoprotein A-I; lipase inhibitor; lysosomal acid lipase
-29-
Note
cDNA Sequence Analysis of a Novel Member of the Three Loop Protein Family
from the Chinese Continental Banded Krait1
You-cun QIAN, Chun-yang FAN, Yi GONG,E and Sheng-li YANG
Shanghai Research Center of Biotechnology, CAS, Shanghai 200233, P. R. China
Received November 2, 1998; Accepted December 21, 1998
The cDNA encoding a novel three loop protein was cloned from cellular RNA isolated from the venom gland of Bungarus multicinctus multicinctus by RT-PCR. The mature protein has 82 amino acid residues. It shared only 25--38 similarity with some cardiotoxins and did not have sequence similarity with neurotoxins, while its cDNA was about 70 similar to both the cDNAs encoding neurotoxins and the cDNAs encoding cardiotoxins.
Bungarus multicinctus multicinctus; three loop protein; cDNA cloning; sequence analysis
-30-
Note
Reidentification of Facultatively Alkaliphilic Bacillus sp. C-125
to Bacillus halodurans
Hideto TAKAMIE and Koki HORIKOSHI
Deep-sea Microorganisms Research Group, Japan Marine Science and Technology Center,
2-15 Natsushima, Yokosuka, Kanagawa 237-0061, JapanReceived November 5, 1998; Accepted January 6, 1999
Alkaliphilic Bacillus sp. C-125 was taxonomically characterized by physiological and biochemical characteristics,||16S rDNA sequence similarity, and DNA-DNA hybridiza||tion analyses. Phylogenetic analysis of strain C-125 based on comparison of 16S rDNA sequences showed that this strain is closely related to Bacillus halodurans. DNA-DNA hybridization analysis was done comparing C-125 and related Bacillus reference strains. The highest level of DNA-DNA relatedness (86) was found between strain C-125 and B. halodurans. Our findings demonstrate that strain C-125 is a member of the species B. halodurans.
alkaliphilic Bacillus halodurans C-125; DNA-DNA hybridization; phylogenetic tree; identification
-31-
Note
Production of Rhamnolipid Biosurfactant by Fed-batch Culture
of Pseudomonas aeruginosa Using Glucose as a Sole Carbon Source
Young LEE, Sang Yup LEE,E and Ji-Won YANG
Department of Chemical Engineering and BioProcess Engineering Research Center,
Korea Advanced Institute of Science and Technology, 373-1 Kusongdong,
Yusonggu, Taejon 305-701, KoreaReceived November 5, 1998; Accepted December 21, 1998
The pH-stat fed-batch culture of Pseudomonas aeruginosa YPJ-80 was done to produce a rhamnolipid biosurfactant. With glucose as the sole carbon source, the final concentrations of cells and rhamnolipid biosurfactant obtained in 25 h were 25 g cell dry weight/l and 4.4 g/l, respectively.
rhamnolipid; biosurfactant; fed-batch culture; Pseudomonas aeruginosa
-32-
Note
A New Affinity Chromatography Using Yeast Invertase-Sepharose 4B
for Purification of Plant Endo--N-acetylglucosaminidases
Yoshinobu KIMURA,a,E Sayuri MATSUO,a Hirotaka INOUE,a Satoshi HARADA,b and Kengo NAKATAb
aDepartment of Bioresources Chemistry, Faculty of Agriculture, Okayama University,
Tsushima-Naka 1-1-1, Okayama 700-8530, Japan
bKagome Research Institute, Kagome Co., Ltd., Nasu-gun, Tochigi 329-27, JapanReceived November 9, 1998; Accepted January 5, 1999
For the purification of plant endo--N-acetylglucosaminidase, in this report, we introduce a new affinity chromatography using the reduced and carboxymethylated yeast invertase (cm-YI) as a ligand. Two plant endo--N-acetylglucosaminidases (endo-LE from tomato fruits (Kimura, Y., et al. Biochim. Biophys. Acta 1381, 27--36 (1998)) and endo-GB from Ginkgo biloba seeds (Kimura, Y., et al. Biosci. Biotechnol. Biochem., 62, 253--261 (1998)) could completely bind to the high-mannose type N-glycans linked to the immobilized yeast invertase and the activities of both enzymes could be recovered by increasing the concentration of NaCl. By using this purification procedure with some other purification procedures, endo-LE could be purified 1,700-fold and endo-GB was purified to apparent homogeneity at 63 kDa as reported previously.
endo--N-acetylglucosaminidase; affinity chromatography; yeast invertase; Ginkgo biloba; Lycopersicon esculentum
-33-
Note
16-O-Demethyl Fusicoccin J and Its 3-Epimer from Fusicoccum amygdali, and Their Seed Germination-stimulating Activity
in the Presence of Abscisic Acid
Takeshi SASSA,E Chang-Shan ZHANG, Naoto TAJIMA, and Nobuo KATO,E
Department of Bioresources, Faculty of Agriculture, Yamagata University, Tsuruoka 997-8555, Japan
Institute of Advanced Material Study, Kyushu University, Kasuga 816-8580, JapanRecieved December 14, 1998; Accepted January 25, 1999
Our search for new metabolites biosynthetically related to fusicoccin with potent plant growth-stimulating activity from the culture filtrate of Fusicoccum amygdali F6 resulted in the isolation of a new derivative of fusicoccin J, as well as fusicoccin J and 16-O-demethyl 3-epifusicoccin J. Its structure was analyzed by 600 MHz NMR spectrometry and identified as 16-O-demethyl fusicoccin J. The biosynthetic relationships among 16-O-demethyl fusicoccin J and its 3-epimer, and fusicoccin J are discussed in connection with the co-occurrence of both of the 3-epimers of 16-O-demethyl fusicoccin J. 16-O-Demethyl fusicoccin J and its 3-epimer showed only low germination-stimulating activity toward lettuce seeds in the presence of abscisic acid (20 M), the latter being slightly more active than the former.
16-O-demethyl fusicoccin J; 16-O-demethyl 3-epifusicoccin J; Fusicoccum amygdali; seed germination; abscisic acid
-34-
Note
Inhibition of Iron/Ascorbate-Induced Lipid Peroxidation by an N-Terminal
Peptide of Bovine Lactoferrin and Its Acylated Derivatives
Hiroyuki WAKABAYASHI,E Hiroshi MATSUMOTO, Koichi HASHIMOTO, Susumu TERAGUCHI,
Mitsunori TAKASE, and Hirotoshi HAYASAWANutritional Science Laboratory and Biochemical Research Laboratory, Morinaga Milk Industry Co., Ltd.,
5-1-83 Higashihara, Zama, Kanagawa 228-8583, JapanReceived December 16, 1998; Accepted January 15, 1999
Bovine lactoferrin (LF) and lactoferricin B (LFcin B), an antimicrobial peptide derived from bovine LF, inhibited thiobarbituric acid-reactive substance (TBARS) formation in a iron/ascorbate-induced liposomal phospholipid peroxidation system. The inhibition of TBARS formation occurred with N-acylated 9-mer peptides with a core sequence of LFcin B and, compared to LFcin B, their antioxidant effect was clearly observed at a concentration almost 100 times lower.
lactoferrin; lactoferricin; antioxidant; TBARS; acylation
-35-
Note
Ion-transport Activity of Phenylpentanoic Acids Occurring in the Roots
of Athyrium yokoscense
Yoshikazu HIRAGA, Masashi KUROKAWA, Jian-Ru GUO, and Takayuki SUGAE
Department of Chemistry, Faculty of Science, Hiroshima University, Higashi-Hiroshima,
Hiroshima 739-8526, JapanReceived December 17, 1998; Accepted February 2, 1999
5-(3-Hydroxyphenyl)pentanoic acid (1) and 5-(3-methoxyphenyl)pentanoic acid (2) occurring in the roots of Athyrium yokoscense showed transport activity to alkaline and alkaline earth metal ions and heavy divalent metal ions.
phenylpentanoic acid; ion-transport activity; metal ion; Athyrium yokoscense; fern
-36-
Preliminary Communication
Isolation and Structural Assignment of 5-Deoxytetrodotoxin from the Puffer Fish
Fugu poecilonotus
Mari YOTSU-YAMASHITA, Bernhard SCHIMMELE,1 and Takeshi YASUMOTO2
Graduate School of Agriculture, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku,
Sendai 981-8555, JapanReceived January 28, 1999; Accepted February 25, 1999
A novel 10,7-lactone type of tetrodotoxin analog, 5-deoxytetrodotoxin, was isolated from the puffer fish, Fugu poecilonotus, and its structure was assigned by spectroscopic methods.
5-deoxytetrodotoxin; structural assignment; biosynthetic pathway; puffer fish
-37-
Preliminary Communication
Total Synthesis of ({)-(2S,3R)-Piscidic Acid via Catalytic Asymmetric
Dihydroxylation of a Trisubstituted Olefin
Hiroaki TOSHIMA, Masatoshi SAITO, and Teruhiko YOSHIHARA
Department of Bioscience and Chemistry, Faculty of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
Received February 16, 1999; Accepted March 8, 1999
({)-(2S,3R)-Piscidic acid was efficiently synthesized with high optical purity (90 e.e.) via Sharpless catalytic asymmetric dihydroxylation of a trisubstituted olefin in only 6 steps from commercially available 4-hydroxyphenylpyruvic acid as the starting material. The reaction proceeded with high optical purity by using the chiral ligands, dihydroquinidine 2,5-diphenyl-4,6-pyrimidinediyl diether or dihydroquinidine 1,4-anthraquinonediyl diether.
piscidic acid; asymmetric dihydroxylation; catalytic asymmetric synthesis
@