It has been reported that thyroxine increased the activity of kynurenine aminotransferase and reduced the activity of kynureinine 3-hydroxylase, with a resulting increase in the reaction of kynurenine to kynurenic acid. By the traditional view, these changes were taken to mean that thyroxine suppressed the conversion of tryptophan to nicotinamide ; however, the effect of this hormone on the conversion ratio of tryptophan to nicotinamide has not yet been actually demonstrated. We, therefore, investigated the effect on the conversion of feeding to rats a nicotinic acid-free, 20% casein diet containing 0.002% thyroxine. The conversion ratio was calculated from the ratio of the sum of the urinary excretion of nicotinamide and its metabolites, N¹-methylnicotinamide, N¹-methyl-2-pyridone-5-carboxamide, and N¹-methyl-4-pyridone-3-carboxamide, to the tryptophan intake. The ratio was statistically higher in hyperthyroid rats than in the control rats. The present data clearly demonstrate that thyroxine increased the conversion of tryptophan to nicotinamide and that the kynurenine channel did not play a critical role in this conversion. Furthermore, the present data suggest that aminocarboxymuconate-semialdehyde decarboxylase played a critical role in this conversion.

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We investigated how much exercise affects the content of NAD when animals were forced to swim until exhausted, because NAD is involved in the re-production of ATP from ADP and inorganic phosphate. The content of NAD in blood decreased when rats swam to fatigue. The degree of the decrease was not related to the training periods. This means that the decreased NAD by exercise was restored during rest. In fact, when rats had swum and then took a rest the next day, the blood NAD content was not different between the exercise and control group. The marginal swimming period of rats was elongated by an intraperitoneal injection of nicotinamide, which is a precursor of NAD. A similar phenomenon was also observed in mice. These data showed NAD is important in continuing exercise.

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Nine peptides to inhibit angiotensin I converting enzyme (ACE) were isolated from sake and sake lees. They were short peptides with 5 or fewer amino acid residues, and many of them had a tryptophan or tyrosine residue at the C-terminus. We synthesized the peptide fragments of IYPRY and YGGY, and measured their inhibitory activity. As a result, we have concluded that hydrophobic amino acids in the sequence and amino acid at C-terminus had an important role in the inhibition. When digested with pepsin and pancreatin, YGGY lost its inhibitory activity but IYPRY maintained its activity. YGGY and IYPRY were orally administered to spontaneously hypertensive rats (SHR) at the dose of 100 mg/kg. YGGY didn't change the blood pressure of SHR, but IYPRY reduced their blood pressure. The hypotensive effect of IYPRY continued for 30h after administration. Also, three dipeptides among the IYPRY fragments, IY, YP and RY, had hypotensive effects, and the effect of RY continued for 30h after administration.

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The oxidative stability of phosphatidylcholine from salmon egg (salmon egg PC) was higher than that of soybean PC in an aqueous solution (pH = 7. 4 at 37°C) with Fe²⁺ -ascorbic acid as a catalyst, although the average numbers of bisallylic positions in the salmon egg PC molecule and in the soybean PC molecule were 4. 28 and 1. 59, respectively. This high average with salmon egg PC was due to its high contents of docosahexaenoic acid (22 : 6n-3, 24.3 mol%) and eicosapentaenoic acid (20 : 5n-3, 14.2 mol%), while the major polyunsaturated fatty acid in soybean PC was linoleic acid (18 : 2n-6, 67.6 mol%). The oxidative stability of both PCs was strongly influenced by an emulsifier. PC was oxidatively most stable when it was dispersed with chicken egg albumin, followed by Tween 20 and deoxycholic acid sodium salt. These data suggest that the oxidative stability of polyunsaturated PC in an aqueous solution is mainly correlated with the conformation of the PC molecule and the phase behavior of PC aggregation.

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To study the effects of food additives on nicotinic acetylcholine receptors (nAChR), they were expressed in Xenopus oocytes that received an injection of mRNA prepared from electroplax of Electrophorus electricus. The response of nAChR elicited by acetylcholine (ACh) was measured electrophysiologically in the presence and absence of aliphatic alcohols and food additives. All compounds examined inhibited nAChR noncompetitively in a concentration-dependent way. The inhibition was stronger when the inhibitors were perfused 1 min before ACh, than when they were perfused simultaneously with ACh. The inhibition of nAChR by aliphatic alcohols (propanol to hexanol) increased as the number of carbon chains increased. The addition of alcohols and food additives did not affect the desensitization of nAChR caused by 2μM ACh. These results suggest that alcohols and food additives bind to the anesthetic binding site in nAChR and inhibit it noncompetitively. However, these compounds will not hinder signal transmission in neuromuscular junctions under physiological conditions, because their inhibition constants are more than 1 mM and muscles usually have more receptors than the number necessary for signal transmission.

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We developed a simple screening method for antioxidant-producing strains using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and screened bacteria from 16 kinds of marine animals that lived in different environments in the sea to find 112 bacterial isolates producing antioxidants. Guided by decoloration of DPPH sprayed on silica gel TLC, uric acid, indole, 3, 4-dimethoxyphenol, and 3-hydroxyindolin-2-one were isolated from the bacterial fermentation broth. Some strains isolated from viscera of fish and shellfish produced uric acid and indole much more under aerobic conditions than less aerobic conditions, strongly suggesting that the bacterial production of the antioxidative compounds is a kind of adaptation to the aerobic conditions.

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Forty-three yeast strains that tolerated organic solvents were isolated by treatment of deep-sea sediments collected at depths of 1200m in Sagami Bay and 1977m in Suruga Bay in the Pacific Ocean with 50% (v/v) n-hexane. With these deep-sea isolates and 58 yeast type strains purchased from culture collections, tolerance to organic solvents was tested. When n-dodecane, n-decane, n-nonane, hexyl ether, n-octane, isooctane, cyclooctane, diphenyl ether, or n-hexane was added to growth medium at the concentration of 10% (v/v), one marine yeast, strain Y-40, could grow in all media except that with n-hexane. This strain was selected as a possible degrader of petroleum hydrocarbons. From results of studies of morphology and taxonomy, it seemed to be a species of Candida. Strain Y-40 could grow well in concentrations of 50% (v/v) of four solvents. The ability to degrade hydrocarbons of kerosene dissolved in 20% (v/v) n-octane was compared for strain Y-40 and the hydrocarbon-assimilating strains C. tropicalis IFO 1400 and Yarrowia lipolytica IFO 1548. Only Y-40 could degrade n-alkanes with a carbon number of more than 8 in the presence of n-octane. The extent of degradation of n-alkanes in the presence of organic solvent which was higher than that without the organic solvent.

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α-Glucosyltransferase was purified from Pseudomonas mesoacidophila MX-45. The molecular weight was estimated to be 63, 000 by SDS-PAGE, and the isoelectric point was pI 5.4. For enzyme activity based on sucrose decomposition, the optimum pH and the optimum temperature were pH 5.8 and 40°C, respectively. The ranges of stable pH and temperature were pH 5.1-6.7 and below 40°C, respectively. The purified enzyme of MX-45 converted sucrose into trehalulose (1-O-α-D-glucopyranosyl-D-fructose) and isomaltulose (palatinose, 6-O-α-D-glucopyranosyl-D-fructose) simultaneously, and the ratio of trehalulose to isomaltulose increased at lower reaction temperatures. Therefore, optimum conditions for trehalulose production were pH 5.5-6.5 at 20°C. The yield of trehalulose from sucrose (20-40% solution) was 91%. The K_m for sucrose was 19.2±3.3 mM estimated by the Hanes-Woolf plot. Product inhibition was observed, and the product inhibition constant was 0.17M. Hg²⁺, Fe³⁺, Cu²⁺, Mg²⁺, Ag⁺, Pb²⁺, glucono-1, 5-lactone, and Tris (hydroxymethyl) aminomethane inhibited the reaction.

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Effects of soybean oil supplementation as a source of linoleic and α-linolenic acids in a palm oil diet on growth and docosapentaenoic acid (22 : 5n-6) levels in tissue lipids in male Sprague-Dawley rats were studied. The rats fed for two months with the diets containing soybean oil (10-50%) in palm oil showed signiticantly higher weight gain than that in rats fed a diet containing only palm oil as a fat source. The highest weight gain was observed in rats fed 50% soybean oil blended in palm oil. Such performance was also better than those observed in rats received diets containing soybean oil alone or canola oil alone. Addition of soybean oil to the palm oil diet prevented 22 : 5n-6 accumulation in plasma, red blood cells, liver, heart, and retinal lipids with a compensative increase of docosahexaenoic acid (22 : 6n-3). Polyunsaturated fatty acid profiles of brain were not affected by the addition of soybean oil. Changes in arachidonic acid contents in organs were not observed. The results indicated that soybean oil supplementation increases the weight gain and prevents the accumulation of 22 : 5n-6 in the tissues which were observed in the rats fed a diet containing palm oil alone.

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Sonication behavior of waxy rice starch in water has been investigated in terms of number average molecular weight and molecular weight distribution evaluated by gel permeation chromatography. Observed results on decreases in number average molecular weight indicated the ultrasonic degradation of waxy rice starch. The rate of degradation was accelerated at or above the temperature where gelatinization started. High sonopower also accelerated the degradation rate. After long sonication, the value of number average molecular weight tended to an limiting constant value, and the molecular weight distribution tended to be fairly narrow. Observing degradation curves of other water soluble α-glucans, dextran, and pullulan, in addition, it was found that branched α-glucans have larger limiting molecular size than the unbranched one has, and an universal degradation curve can be obtained by plotting the ratio of the molecular size of the degraded α-glucan to the correspondent limiting one against time.

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Eight strains of species of the teleomorphic genus Dekkera (and anamorphic genus Brettanomyces)were examined for their partial base sequences of 18S and 26S rRNAs. In the 26S rRNA partial base sequencings in positions 493-622 (130 bases) of 26S rRNA, D. bruxellensis (type species) (and B. bruxellensis, type species) and D. anomala (and B. anomalus) were related phylogenetically (percent similarities, 73-82). The percent similarity of D. naardenensis and D. custersiana were very low (48-56 and 48-53, respectively). In the 26S rRNA partial base sequencings in positions 1611-1835 (225 bases) of 26S rRNA, D. bruxellensis (and B. bruxellensis) and D. anomala (and B. anomalus) were related phylogenetically (base differences, 8-6). The base differences of D. naardenensis and D. custersiana were 46-38 and 38-27, respectively. In the 18S rRNA partial base sequencings in positions 1451-1618 (168 bases) of 18S rRNA, D. bruxellensis (and B. bruxellensis) and D. anomala (and B. anomalus) were closely related phylogenetically (base difference, one). The base differences of D. naardenensis were three with the above-mentioned two species. In contrast, D. custersiana was distant phylogenetically (base differences, 10-9). The sequence data obtained were discussed taxonomically, especially on setting up a new teleomorphic genus for D. custersiana.

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The subsite structure of Rhizopus glucoamylase was identified for the hydrolytic reaction of isomaltooligosaccharides at 25°C and at pH 4. 5. The arrangement of the subsite affinities A_i's (i is the subsite number) was evaluated as follows : A₁= -6. 0, A₂=13. 8, A₃=4. 6, A₄=1.5, A₅=0.6, A₆= -0.5, and A₇ = 0.2 (in kJ mol^-1 unit). The intrinsic rate constant for the hydrolytic reaction in the productive binding mode of substrates, k_int, was 10.2s^-1. Larger values of K_m for isomaltooligosaccharides compared with those for maltooligosaccharides were attributed to smaller values of A₁ and A₂ compared with those for maltooligosaccharides, and smaller values of k₀ were attributed to smaller values of A₁ and k_int. Steady-state inhibitory kinetic studies showed that both isomaltooligosaccharides and maltooligosaccharides bind to the same active site of the enzyme.

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The Escherichia coli ubiA gene coding for 4-hydroxy benzoate octaprenyl transferase is thought to be a key enzyme of ubiquinone biosynthesis. Strains with ubiA disrupted were constructed by chromosomal gene replacement with the chloramphenicol resistance gene. The respiration-defective phenotype of the ubiA mutant was complemented by expression of the COQ2 gene encoding the 4-hydroxy benzoate hexaprenyl transferase of Saccharomyces cerevisiae and such strains produced ubiquinone-8. This strongly supports the idea that COQ2 catalyzes the same enzymatic reaction with UbiA and the substrate specificity of COQ2 is broad. Study of the expression of ubiA using an ubiA-lacZ fusion system showed that the ubiA expression was catabolite-repressed by glucose. This repression by glucose was obvious in the arcA mutant. ArcA is the positively acting transcriptional regulator of the oxygen regulated genes. The molecular mass of the protein product of ubiA was 32 kD, found using the over-expression of the ubiA gene.

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Localization analysis of scopolamine and hyoscyamine 6β-hydroxylase (H6H ; EC 1.14.11.11) contents in Duboisia root cultures showed that scopolamine biosynthesis was accompanied by root elongation. A new two-stage culture method in which the first stage promotes lateral root induction and the second stage enhances root elongation therefore was devised to obtain high scopolamine production. Consequent development of the most suitable media for each stage of culture increased scopolamine productivity 1.8 times that obtained with a one-stage culture. A total of 2500 mg dm^-3 of scopolamine was produced when this two-stage culture was combined with our high-density culture method.

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The effects of oxygen on nicotine and tropane alkaloid production in root cultures of Duboisia myoporoides were investigated. Duboisia roots cultured in air produced both nicotine and tropane alkaloids equally. However, when roots were cultured in pure oxygen, the metabolic flux to tropane alkaloids increased, and that to nicotine alkaloids decreased. Intermediate product analysis by GC-MS showed an increase in tropine, but decreases in acetyl derivatives of tropane alkaloids and tropine esters with low-class fatty acids. Furthermore, hyoscyamine 6β-hydroxylase (H6H, EC 1.14.11.11, the key enzyme in the pathway from hyosyamine to scopolamine) also increased. These results suggest that pure oxygen contributes to scopolamine production not only by activating the biosynthetic steps for scopolamine, but also by inactivating the biosynthetic steps for nicotine and other tropine derivatives.

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Two chitin synthase genes, designated chsA and chsB, were isolated from Aspergillus nidulans with the Saccharomyces cerevisiae CHS2 gene as the hybridization probe. Nucleotide sequencing showed that chsA and chsB encoded polypeptides consisting of 1013 and 916 amino acid residues, respectively ; the hydropathy profiles of the enzymes were similar to those of other fungal chitin synthases. Northern analysis indicated that both genes were transcribed, suggesting that cellular chitin in A. nidulans is synthesized by at least two chitin synthases. For examination of the roles of the chitin synthase genes in cell growth, gene disruption experiments were done. The chsA disruptant grew as well as the wild-type strain, but the chsB disruptant had severe growth defects that could not be overcome by the addition of 1.2M sorbitol as an osmotic stabilizer. These findings suggested that chsB but not chsA is essential for hyphal growth.

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A Bacillus subtilis 168 strain carrying an inversion of about 1600 kb-long chromosomal DNA was isolated. Physical and genetic analyses demonstrated that the inversion was generated as a result of homologous recombination between two homologous sequences integrated at the met and leuB loci. This is the first clear evidence of a large stable chromosomal inversion induced by homologous recombination in B. subtilis.

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In attempts to find new sources of astaxanthin, approximately 200 strains of marine bacteria were collected from the sea near Okinawa Islands for screening. Silica gel TLC, VIS, EIMS, ¹H-NMR, CD, and optical resolution HPLC data indicated that one of the strains, Agrobacterium aurantiacum, produced (3S, 3'S)-astaxanthin and (3S, 3'R)-4-ketozeaxanthin.

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To study the function of SecA protein and the protein translocation system of Bacillus subtilis, wild-type and mutant SecA proteins were characterized in vivo and in vitro. SecA protein was abundant in a wild-type strain (168) and existed in a stable homodimer. In contrast to this, SecA341 (ts) protein having an amino acid replacement from proline to leucine at residue 431 was undetectable by immunoblotting in the cell lysate of a secA341 mutant (TB301) at the nonpermissive temperature, 42°C. Pulse-chase studies using ³⁵S-methionine showed that newly synthesized SecA protein was rapidly degraded in the mutant at 42°C. Purified SecA341 protein was more sensitive to trypsin and subtilisin than purified wild-type SecA protein in the presence of ATP. These results indicate that the secA341 mutation causes the rapid degradation of mutant SecA protein and a concomitant protein translocation defect in the cell.

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The presence of intestinal lectin-binding glycoproteins on the cell surface of Lactobacillus acidophilus group lactic acid bacteria was examined. The cell-surface components were extracted with 2M guanidine hydrochloride, and electrophoresed by SDS-PAGE followed by electroblotting. Several glycoproteins were detected on the blots of the extracts from 7 of the 11 strains tested. The distribution of glycoproteins seemed to be specific for strains rather than for species. β-Galactoside-specific lectin was extracted from chicken intestine, and then was labeled with horseradish peroxidase. The binding of the lectin to glycoproteins detected was assayed by a ligand blotting procedure using the labeled lectin. The lectin-binding glycoproteins estimated to be 60.2 and 43.0 kDa, respectively, were detected from strain L. acidophilus JCM1132^T, but not from other strains. The binding was inhibited in the presence of lactose, indicating that the binding was specific. Presumably, the interaction between bacterial cell glycoproteins and intestinal lectins participates in the specific adherent of the bacterium to intestinal epithelial surfaces.

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This study investigated the effects of sesamin and α-tocopherol on eicosanoid production and immune function in the rat. Male Brown-Norway rats, 4 weeks of age, were given either control, 0.5% sesamin, 0.5% α-tocopherol, or 0.5% sesamin plus 0.5%α-tocopherol diets for 3 weeks. When sesamin and tocopherol were given together, the proportion of 20 : 4n-6 phosphatidylcholine (PC) was significantly lowered in liver and lung, while that of 18 : 2n-6 and 20 : 3n-6 was significantly increased in liver. Simultaneous administration of these compounds significantly reduced the production by the lung of leukotriene C₄ (LTC₄), but there was no effect on the splenic LTC₄ production and the plasma prostaglandin E₂ concentration. Sesamin and tocopherol, either separately or in combination, significantly reduced both the proportion of splenic CD4⁺and CD8⁺ T cells, but the change in the CD4⁺ / CD8⁺ ratio was not significant. The effects of sesamin and tocopherol feeding on serum levels of IgA, IgE, and IgG were not so marked, but tocopherol significantly decreased the serum IgM level. These results suggest that the feeding of sesamin and tocopherol suppress LTC₄ production through the decrease in the arachidonic acid level in lung PC.

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For improvement of the production of nitrile hydratase (NHase) from Rhodococcus sp. N-774 by recombinant DNA techniques, several plasmids, each of which had a deletion of the upstream or downstream region of the genes encoding the α and β subunits of NHase, were constructed. Enzyme assays of recombinant R. rhodochrous and Escherichia coli cells showed that a downstream region of the NHase genes was indispensable for the production of active NHase in both cells, but for the production of the active amidase, no genes other than the amidase structural gene were required. The nucleotide sequence of the downstream region contained a single open reading frame (Orf1188) with 396 amino acids. Orf1188 showed similarity in amino acid sequence to P47K, an open reading frame found downstream of the NHase genes from Pseudomonas chlororaphis B23, and also to the cobW gene product, which may be involved in cobalamin biosynthesis in Pseudomonas denitrificans. Because the distance between the TGA stop codon for the NHase β-subunit and the ATG codon for Orf1188 is only 98bp, and because production of both Orf1188 and NHase is dependent on a promoter upstream of the amidase gene, these genes appear to be co-transcribed in a polycistronic manner, forming an operon. By optimization of the culture conditions of R. rhodochrous carrying pKRNH2, which contained the amidase, NHase, and Orf1188 genes, the transformant showed the NHase activity 6-fold higher than that of the original strain, Rhodococcus sp. N-774.

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The gene encoding a β-galactosidase from Enterobacter cloacaeGAO was cloned and expressed in Escherichia coli. The nucleotide sequence of the insert of a positive clone had an open reading frame of 3084bp that encoded a polypeptide of 1028 amino acid residues with a calculated molecular mass of 116, 677 daltons. The amino acid sequence of β-galactosidase deduced from the nucleotide sequence, especially the sequence around the putative active site and of the fourteen regions, showed significant homology to β-galactosidases of other microorganisms, E. coli, Klebsiella Pneumoniae, Lactobacillus bulgaricus, and Clostridium acetobutylicum.

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The formation of a complex between (1→3)-β-D-glucan and congo red in dilute alkaline solutions (0.1 and 0.15 M sodium hydroxide)where the glucan takes an ordered conformation was studied by measuring visible absorption spectra of the solutions at various temperatures between 15 and 35°C. The average number of the glucose residues forming the binding site to accommodate one dye molecule decreased with increasing temperature or decreasing alkaline concentration, suggesting possible conformational changes of the glucan chain. The complex formation constant, K, increased with increasing temperature, and thermodynamical parameters, ΔH° and ΔS°, for the complex formation in 0. 1 M and 0.15 M aqueous NaOH solutions were obtained at 25°C to be 14 kcal/mol and 77e.u. (0.1 M), and 12 kcal/mol and 68 e. u. (0.15 M), respectively. These results indicate that the driving force for the complex formation is entropic in nature stemming from the decrease of"iceberg formation".

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Internal amino acids of Brevibacterium sp. JCM6894 were analyzed when the cells were grown in various concentrations of NaCl. γ-Aminobutyric acid was accumulated in parallel with the increase of external NaCl concentrations. During transient salt stress, 4-hydroxyproline was synthesized in the cells.

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A new series of 3-(alkylthio)carbonyl derivatives of methyl thiazolidine-4(R)-carboxylate were synthesized, and they inhibited growth of the roots of Brassica campestris L. subsp. rapa HooK. fil. et ANDERs. Among them, the S-cycloPentyl derivative was the strongest inhibitor. These compounds, except for a n-octylthio derivative, decreased chlorophyll contents in the cotyledons of this plant as compared with the control.

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5-Thio-D-glucose showed strong growth-inhibitory activity in the roots of the following plants : Brassica campestris L. subsp. rapa HOOK. fil. et ANDERS, Sesamum indicum L., Lactuca sativa L. var. longifolia LAM, Abelmoschus esculentus MoENcH, Glycine max MERRILL, Echinochloa utilis OHwI et YABUNO, and Allium tuberosum RoTTLER. The comPound strongly inhibited the growth of the roots of E. utilis and A. tuberosum even at the low concentration of 5. 0 x 10^-5M. The radicles of plants treated with 5-thio-D-glucose showed negative geotropism. The 5-thio-D-glucose-induced inhibition in B. campestris was reversed by addition of D-glucose.

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Tetrahydropyran-2- and -3-carboxylic acids were resolved by using quinine. The enantiomeric purity of the corresponding methyl esters (1 and 2) was determined by proton NMR, using a lanthanide chiral shift reagent [Eu(hfc)₃] in the ratio 1 : 3 (substrate/shift reagent). The relative attractant activity of the racemic, and ( + ) and (-) isomers of these esters was evaluated against Blattella germanica (L.) and Supella longipalpa (F.). The results show that the activity order for l was (-)>(+)>racemic, and for 2 was (+)>(-)>racemlc.

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An assay for urinary methylmalonic acid by high-pressure liquid chromatography was devised. Methylmalonic acid could be assayed over a range of 5-80μg by this method, which is one of the most convenient and useful assays for the acid in urine as an index of cobalamin deficiency.

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A sheep liver cDNA library was screened with a BstEII fragment of human angiotensinogen cDNA to obtain sheep angiotensinogen cDNA. The cDNA sequence showed that preangiotensinogen con-sisted of 452 amino acid residues (49 kDa) of angiotensinogen and 24 residues of a signal peptide. Recombinant sheep angiotensinogen (56kDa) was expressed in COS-7 cells.

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The simultaneous use of hen egg lysozyme and mutanolysin, N-acetylmuramidase SG, showed synergistic effects on the lytic action and more effectiveness for protoplast formation of Streptococcus bovis IF 12058. The frequency of regeneration reached 100% after 7 days of incubation under the improved conditions and by a method in which protoplasts were overlaid with the agar medium layer.

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Using a mouse SPARC (Secreted Protein, Acidic and Rich in Cysteine) cDNA clone as the probe, three clones were isolated from a cDNA libray of bovine aortic endothelial cells (BAEC). Inserted sequences in them were identical with that of bovine bone osteonectin except for the deletion of the TGC codon encoding Cys-193. North-ern blot analysis and metabolic radio-labeling of BAEC showed that gene expression and synthesis of the osteonectin variant is stimulated by transforming growth factor (TGF) β, a basic fibro-blast growth factor (FGF), or a naturally occurring splicing variant of hepatocyte growth factor (varHGF).

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Since the lesioned part of the Exacum affine cv. plant showed remarkable insect attractivity to males of the giant danaid butterfly, Idea leuconoe, the volatile components of E. affine cv. were analyzed. The main component in every part was identitied as 2'-hydroxy-4'-methoxyacetophenone (paeonol), and authentic paeonol crystals showed similar insect attractivity.

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The epiphytic microfloral population on damaged and non-damaged leaf surfaces of Polymnia sonchifolia (Compositae) was examined, and metabolic properties of microbes predominant on the damaged leaves were studied. On the damaged leaf surface, some epiphytic Gram-negative bacteria able to metabolize phenolic compounds of plant origin were highly ascendant. The most dominant bacterium, Pseudomonas viridiflava had a high activity of peroxidase on pyrocatechol, while the second major bacterium Phyllobacterium myrsinacearum, produced 4-hydroxycinnamate decarboxylase. Thus, it was likely that epiphytic bacteria predominant on damaged leaves can metabolize plant phenolics. These epiphytic bacteria frequently formed mixed colonies during their isolation, and the mixed colonies were retarded in their growing rate compared with single colonies of each.

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A new phosphatidyl derivative, 1, 2-dipalmitoyl-3-sn-phosphatidylgenipin (DPP-genipin), was found to be synthesized by the transfer reaction of a dipalmitoylphosphatidyl residue from 1, 2-dipalmitoyl-3-sn-phosphatidylcholine (DPPC) to genipin by phospholipase D (PLD) from Streptomyces sp. in a biphasic system. DPP-genipin also transferred its phosphatidyl residue to choline by PLD, to reproduce DPPC and liberate genipin. DPP-genipin showed 6 to 52 times stronger cytotoxity than genipin to Hela cells, human embryonic lung fibroblasts (HEL), and MT-4cells.

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An indigenous plasmid, named pAH4, was detected in a cellulose-producing Acetobacter strain. This plasmid, consisting of 4002bp, contained an AT-rich region and encoded several open reading frames, as deduced by the complete nucleotide sequence. One of the putative open reading frames showed homology with replication proteins of other plasmids. A shuttle vector of Escherichia coli and this strain was constructed by connecting pAH4 to pUC18. Electroporation of the shuttle vector into the strain yielded 1. 7 x 10⁵ampicillin resistant transformants per μg DNA. The shuttle plasmid was very stably maintained in the strain.

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Dehydrololiolide, isolated from tobacco leaves, was synthesized via the intramolecular aldol reaction, Reformatsky reaction, and Wittig reaction of the key intermediate keto esters.

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Thermostabilities of component enzymes in the pyruvate dehydrogenase complex from Bacillus stearothermophilus decreased in the order lipoamide dehydrogenase, lipoate acetyltransferase, and pyruvate decarboxylase (E1). Fluorescence of an extrinsic 8-amino-1-naphthalenesulfonate (ANS) increased with inactivation of E1. The thermal denaturation of the enzymes resulted in disassembly of the complex. E1 was involved in a resulting aggregate of the complex. The interaction between ANS and denatured E1 accounted for an increase in fluorescence.

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6-O-Tosyl (1, d. s. 0.94, 80% yield), 6-deoxy-6-iodo (2, d. s. 0.49, 86% yield) and 6-deoxy (3, d. s. 0.49, 50% yield) derivatives of N-acetylchitosan were prepared, and a ¹³C CP/MAS NMR spectral analysis was performed because no suitable solvent for 3 was found. The ¹³C signal for CH₃ at C-6 in 3 was detected at 18.9 ppm, and that for C-4 in 1-3 appeared at 72.2-72.7ppm, which is in a higher magnetic field than those (82.5-86.0ppm) in N-acetylchitosan, 6-O-(ethylthio), 6-O-(benzylthio)- and 6-O-(methylthio)-thiocarbonyl derivatives, chitosan, and chitin. This strongly suggests a different molecular conformation for 1-3.

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An endopolygalacturonase from Physalospora piricola was purified to apparent homogeneity by column chromatographies. The molecular weight was estimated to be 38, 000 by SDS-PAGE, and the isoelectric point was around pH 7. 6. The amino acid composition was similar to those of endo PGs from other fungi. The enzyme was most active at pH 4.9 and stable from pH 5 to 7. Oligogalacturonic acids with a degree of polymerization higher than three were readily hydrolyzed by the enzyme, but trigalacturonic acid only slightly.

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Reaction conditions of cell-free protein synthesis using wheat germ extract were examined to prolong the period of protein synthesis in a batch reaction. By optimizing conditions for ATP regeneration system involved in the cell-free system, protein synthesis continued about 4 hours, so that about 17μg dihydrofolate reductase protein was obtained in 1ml of a reaction mixture. It suggests that maintaining ATP concentration is the primary requirement for long-life cell-free protein synthesis.

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A new extracellular quinoprotein oxidase named enacyloxin oxidase (ENX oxidase), which is involved in biosynthesis of ENX IIa, a congener of ENX, was found in the culture supernatant of Frateuria sp. W-315 and purified as a homogeneous protein on SDS-PAGE. ENX oxidase was shown to have a molecular mass of 73kDa by SDS-PAGE and 79kDa by gel filtration. The enzyme was inhibited by various carbonyl reagents and the activity was stimulated by addition of PQQ. This is the first report on a quinoprotein oxidase that is secreted into the culture medium in the logarithmic growth phase, and acts for biosynthesis of the antibiotic.

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Histamine may be involved in the regulation of hematopoiesis. However, it remained obscure what kind of cells are responsible for its synthesis in bone marrow (BM). In this study, a pure population of macrophages were raised from BM of W/W^v mice, which are genetically deficient in mast cells. The addition of Escherichia coli lipopolysaccharide (LPS) or murine recombinant granulocyte/macrophage colony-stimulating factor (mrGM-CSF) alone had essentially no effect on histamine synthesis. However, the latter rendered the cells responsive to LPS, leading to a marked increase in HDC-dependent histamine synthesis.

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Glycine-rich protein (GRP), a cell wall protein, was extracted with hot water from the aleurone layer of soybean seeds. GRP was purified by adsorption on DEAE-Sephadex, Sephadex G-100 gel chromatography, and anion exchange HPLC. The estimated molecular size of GRP was approximately 30kDa and GRP contained 59% glycine and 15% serine. The N-terminal amino acid sequence was a novel Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-Gly-.

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A novel taxane diterpenoid was isolated from the heartwood of Japanese yew and found to be taxa-4(20), 11-diene-2α, 5α, 10β, 14β-tetraol 2α, 5α, 10β-triacetate 14β-(S)-2'-methylbutyrate.

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Growth of two strains of methicillin-resistant Staphylococcus aureus (MRSA) was inhibited by 6.25μg/ml of anacardic acid and 0.78μg/ml of totarol, and these two compounds were found to be bactericidal. Anacardic acid was bactericidal against MRSA at any stage of growth.

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1 -Stearoyl-2- [15'-(S)-hydroperoxyicosatetraenoyl] -phospho-serine was synthesized for the first time by utilizing lipoxygenase-catalyzed hydroperoxidation, protection of the hydroperoxy group, DCC-mediated esterification and phospholipase D-catalyzed transphosphatidylation. A hydroxy form of this hydroperoxide was prepared by reducing the hydroperoxy group with triphenylphosphine. Unoxidized phosphatidylserine was also prepared as a reference compound.

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The reactions of 3-aryl-1-methyl-1, 2, 4-triazolin-5-ones with 2-bromopropionic acid esters afforded 2-(3-aryl-1-methyl-1, 2, 4-triazol-5-yl)oxypropionic acid esters regioselectively, which showed good branching activity along with some stunting activity against soybeans in a soybean branching assay.

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A new phytotoxin, FCRR (Fusarium crown and root rot)-Toxin was isolated from the culture filtrate of Fusarium oxysporum f. sp. radicis-lycopersici. The structure of FCRR-Toxin was established as I on the basis of spectroscopic evidence. The threshold concentration of induced leaf necrosis for "Momotaro, " a susceptible cultivar of tomato (Lycopersicon esculentum Mill.), by this toxin was found to be 0.25μg/ml.

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An efficient six-step degradation method for the protein phosphates inhibitor, tautomycin (1), was developed in order to synthesize various analogues of 1 for their biological evaluation. This route allows rapid and multi-gram access to key intermediate 2 in the total synthesis of 1 .

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