Hypoxanthine phosphoribosyltransferase (EC 2.4.2.8) of a strain of Streptomyces cyanogenus was purified 1, 900-fold to an apparent homogenity from cell-free extracts. The enzyme had a molecular weight of 150, 000 and consisted of eight identical subunits with a molecular weight of 18, 000. The isoelectric point was at pH 4.4. The enzyme required Mg²⁺ or Mn²⁺ for activity and had a pH optimum at 8.5. Hypoxanthine and guanine were good substrates for the enzyme. Xanthine was a very poor substrate and adenine was not a substrate. Apparent Km values of the enzyme for hypoxanthine, guanine and 5-phosphoribose-l-pyro-phosphate were 1.6×10^-6, 2.7×10^-6 and 6.3×10^-5 at, respectively. All purine nucleotides tested inhibited the activity significantly, apparently by competing with 5-phosphoribose-l-pyrophosphate.

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Ammonia supplied to tea roots was mainly stored as theanine, glutamine and arginine in roots and leaves before the sprouting of new shoots. These compounds were transferred to growing points (new shoots) when the tea plants began to grow after the resting period. Theanine, a remarkable amide in tea plants, was, especially, concentrated in the new shoots. The accumulation of theanine in new shoots was due not only to large transports from roots, but also to slow utilization in the new shoots.
L-Methionine-DL-sulfoximine (MSO) suppressed the reconstruction of ammonia into amino acids and amides, especially theanine. Furthermore, MSO inhibited the activity of glutamate synthase. However, the activity of glutamate dehydrogenase was not suppressed.

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L-Tryptophan-α-ketoisocaproate aminotransferase (tentative term) was purified from Pseudomonas sp., utilizing α-aminoisobutyrate. The purified enzyme was shown to be homogeneous by polyacrylamide gel disc electrophoresis and ultracentrifugation. The molecular weight of this enzyme was determined to be 90, 000±5, 000 by sedimentation equilibrium and 110, 000±5, 000 by Sephadex G-150 gel filtration. The holoenzyme exhibited absorption maxima at 330nm and 415nm. The addition of L-leucine shifted the 415nm peak to 330nm.
This enzyme showed a very broad substrate specificity, that is, high activity toward the branched chain, straight chain and aromatic amino acids and the corresponding a-keto acids, but it was not active to L-glutamate and α-ketoglutarate. The apparent Michaelis constants were determined as follows: L-leucine 0.4mM, L-isoleucine 0.5mM, L-valine 4.5mM, L-phenyl-alanine 0.8mM, L-tryptophan 1.4mM, L-tyrosine 1.0mM, α-ketoisocaproate 0.03mM, α-ketoiso-valerate 0.11mMand phenylpyruvate 0.08mM.

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The regulation of acid phosphatase synthesis by various phosphate compounds was examined in Baker's yeast protoplasts. Synthesis was repressed by inorganic phosphate and phosphomonoesters. Phosphomonoesters were hydrolysed by a small amount of non-specific acid phosphatase present in the protoplast membrane. The inorganic phosphate that was liberated and incorporated into protoplasts probably repressed acid phosphatase synthesis. Phosphodiesters, such as 3', 5'-cyclic AMP, 3', 5'-cyclic CMP and 3', 5'-cyclic GMP, promoted acid phosphatase synthesis. The effect of 3', 5'-cyclic AMP was not to overcome hexose repre-ssion, because high hexose did not repress acid phosphatase synthesis. 3', 5'-cyclic AMP did not overcome repression of the enzyme synthesis by inorganic phosphate. From these observa-tions 3', 5'-cyclic nucleotides probably had some effect on the yeast acid phosphatase-synthesiz-ing system but the exact role of the nucleotides is obscure.

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The cell wall polysaccharide of cotyledon of Tora-bean (Phaseolus vulgaris), which surrounds starch granules, was isolated from saline-extraction residues of homogenized cotyledon, as alkali-insoluble fibrous substance. Alkali-insoluble residue, which had been treated with α-amylase (Termamyl), had a cellulose-like matrix under the electron microscope. It was composed of L-arabinose, D-xylose, D-galactose and D-glucose (molar ratio, 1.0:0.2:0.1:1.2) together with a trace amount of L-fucose. Methylation followed by hydrolysis of the polysac-charide yielded 2, 3, 5-tri-O-methyl-L-arabinose (3.3 mol), 2, 3, 4-tri-O-methyl-D-xylose (1.0 mol), 2, 3-di-O-methyl-L-arabinose (3.7 mol), 3, 4-di-O-methyl-D-xylose (1.0 mol), 2-O-methyl-L-arabinose and 2, 3, 6-tri-O-methyl-D-glucose (12.7 mol), 2, 6-di-O-methyl-D-glucose (1.2 mol) and 2, 3-di-O-methyl-D-glucose (1.0 mol).
Methylation analysis, Smith degradation and enzymatic fragmentation with cellulase and α-L-arabinofuranosidase showed that the L-arabinose-rich alkali-insoluble polysaccharide possesses a unique structural feature, consisting of β-(l→4)-linked glucan backbone, which was attached with side chains of D-xylose residue and β-D-galactoxylose residue at O-6 positions and α-(l→5)-linked L-arabinosyl side cams (DP=8) at O-3 positions of β-(1→4)-linked D-glucose residues, respectively.

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Purified glycerol oxidase from Aspergillus japonicus AT 008 was homogeneous by ultracentrifugation and acrylamide gel electrophoresis. The molecular weight was determined to be 400, 000 by sedimentation equilibrium, and the isoelectric point was found to be 4.9 by isoelectric focusing. The enzyme showed spectral characteristics of a heme protein. The reduced form possessed absorption maxima at 557 and 430nm and the oxidized one at 557, 530, 420, 280, and 238nm. The heme in the enzyme was identified as protoheme IX (one mol per mol of enzyme protein).
Glycerol was the best substrate for the enzyme, and the Km value for glycerol was determined to be 10.4nm. Dihydroxyacetone was oxidized at 59% of that for glycerol, but glycerol 3-phosphate, dihydroxyacetone phosphate, methanol, and ethanol were not oxidized at all. The enzyme had an optimal pH at 7.0 with glycerol as substrate, and the enzymatic activity increased by treatment in alkaline pH. The enzyme was also activated by addition of several divalent metal ions including Zn²⁺, Ni²⁺, and Mg²⁺.

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Glucoamylase[α-1, 4: 1, 6-glucan-4: 6-glucohydroease, EC 3.2.1.3] from Rhizopus niveus was entrapped in polyacrylamide gels and adsorbed onto SP-Sephadex C-54 to elucidate the thermostability mechanism of immobilized enzymes. The thermal stability of immobilized glucoamylase entrapped in polyacrylamide gels was enhanced slightly compared with glucoamylase in free solution, and was independent of the acrylamide monomer concentration and N, N'-methylene-bis (acrylamide) content. To explain this phenomenon, the cellular structure of polyacrylamide gel was taken into consideration in addition to interactions between gluco-amylase and gel, and a decrease in dielectric constant in the gel [S. Moriyama et al., Agric. Biol. Chem., 41, 1985 (1977)¹⁾]. On the other hand, immobilized glucoamylase bound to SP-Sephadex by ionic interaction showed lower stability than free glucoamylase, and much greater stability than glucoamylase in the presence of dextran sulfate, a constituent of SP-Sephadex. Thermal stabilities for the free and immobilized enzymes were also compared at the pH not in the bulk solution, but in the SP-Sephadex.

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1, 6-Anhydromaltose was chemically converted into a couple of pseudodisaccharides containing different inosamine (3-amino-3-deoxy-epi- and 1-amino-l-deoxy-1 L-myo-inositol) residues as constituents via 6-deoxy-6-nitro-maltose derivatives.

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Bacillus cereus IFO 3131 produces the largest amount of Crithidia factors of 27 bacterial species tested (J. Bacterial., 104, 197, 1970). The factors in the culture fluid and cell were isolated with a Florisil column and reversed-phase high-performance liquid chromatography (HPLC). They were identified by HPLC, fluorescence and ultraviolet spectra, thin-layer chromatography and bioassay. The major factor in the cell was D-erythro-neopterin and that in fluid was 6-hydroxymethyipterin and pterin.

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The degradation of herbicide atrazine (2-chloro-4-ethylamino-6-isopropylamino-1, 3, 5-triazine) by a soil bacterium is reported. The bacterium involved is a species of Nocardia, which utilizes the atrazine as the sole source of carbon and nitrogen. A new metabolite, 4-amino-2-chloro-1, 3, 5-triazine, of the degradation of atrazine in the presence of glucose has been identified. The results further substantiated that atrazine can be degraded by soil microorganisms and indicated that deamination can also occur, as well as dealkylation. 4-Amino-2-chloro-1, 3, 5-triazine did not show phytotoxic activity to oat (Avena sativa L.), demonstrating that deamination insures detoxification.

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Oligosaccharides IV and V were newly isolated as additional neutral sugar fragments from the partial acid hydrolyzate of antibiotic K-52B. Methylation analysis and Smith degradation of these oligosaccharides indicated that the structures were Glc_p (1→4)-Gal_p(1→4)-Fuc-(1→4)-Glc_p-(1→ for oligosaccharide IV and Glc_p (1→4)-Galp_p-(1→4)-Fuc-(l→4)-Glc_p-(1→5)-Ara_f-(1→ for oligosaccharide V.

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The effect of calcium activated factor (CAF) on enzymatic properties of actin and myosin was investigated. SDS polyacrylamide gel electrophoresis revealed that CAF did not degrade actin, but a slight degradation was found in myosin during CAF digestion, which might have been due to contaminated protease (s) in CAF preparation. No influence was found in EDTA ATPase of myosin and polymerization of G-actin during CAF digestion. However, heavy meromyosin (HMM) ATPase activating ability of actin was slightly decreased during CAF digestion. Although CAF digestion slightly decreased the biological activity of myofibrillar proteins, a single sarcomere prepared by CAF digestion is a useful model for studying muscle contraction because of its almost intact contractility.

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The structure of the novel antibiotic reductiomycin has been clarified by X-ray diffraction studies. The structure was determined by the direct method and refined to an R value of 0.098. Reductiomycin has a unique chemical structure with a strong intramolecular hydrogen bond with the 0…0 distance of 2.509 Å.

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A sensitive and simple method for separation of eight unconjugated pterins has been developed and used to analyze banana, seeds, nuts, cereals, leaves, royal jelly and human urine. Acid extraction, a simple clean-up using Florisil, and reversed-phase high-performance liquid chromatography with a fluorescence detector were employed. The eight pterins analyzed were: 6-carboxypterin, erythro-neopterin, threo-neopterin, xanthopterin, biopterin, isoxanthopterin, 6-hydroxymethylpterin and pterin. Lumazine compounds, 6-hydroxymethyllumazine and lumazine, were tentatively identified. Over ten ng of the unconjugated pterins/g of sample were quantified. Characteristic patterns of pterins were observed in each product. It was also shown that this analytical method was useful in diagnosis of malignant hyperphenylalaninemia.

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Methyl 6', 6'-didemethyl abscisate (5) was synthesized and assayed to elucidate the physiological activity of methyl substituents on the cyclohexene ring of abscisic acid (ABA). During this study two new chiral stereoisomeric analogs 6 and 7 were synthesized from l- and d-carvone. The rice seedling assay and germination assay of garden radish showed that 6'-methyl groups of ABA were not important in biological activity and that 5'-isopropenyl analogs 6 and 7 were inactive.

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Optically active dictyopterenes A and B and their geometrical isomers were stereoselectively synthesized by condensation of acrolein with carboethoxymethyl dimethylsulfonium bromide and by the Wittig reaction between (+)-2-vinylcyclopropylcarbaldehyde, which was derived from partially resolved (+)-(1S, 2R)-2-vinylcyclopropanecarboxylic acid, and phosphonium salts in liquid-solid two-phase systems using crown ethers.

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Pseudomonas C₄₅ is the mutant of facultative methanol-oxidizing bacteria, Pseudomonas N842, and this mutant accumulated CoQ₁₀ and CoQ₁₁, Minor components of CoQ homologs were studied and four homologs were isolated. Two of them with higher Rf values than that of CoQ₁₀ on the reversed-phase chromatogram were identified as CoQ₈ and CoQ₉. One CoQ homolog with lower Rf value than that of CoQ₁₁ was purified to crystaline state and identified as CoQ₁₂ by chemical properties and NMR, mass and IR spectrometries. The fourth CoQ homolog with the lowest Rf value was identified as CoQ₁₃, which was novel in nature. CoQ₈ through CoQ₁₃ were also detected in similar methanol-oxidizing bacteria by high performance liquid chromatography.

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Lutein bound to some proteins to form complexes soluble in aqueous solutions. The formation of complexes was accompanied by novel changes in the spectroscopic properties of lutein in the visible wavelength region. The absorption peak with a maximum at 446nm and two sub-peaks at 423nm and 474nm in ethanol coalesced to form a single peak at 384nm without fine structures. This lutein with virtually no optical activity in the visible region in organic solvents showed a circular dichroic spectrum which was roughly point-symmetrical with respect to the wavelength of the maximum in absorption spectrum.
These spectroscopic properties indicated that lutein molecules two or more in number form an aggregate with chirality in their mutual arrangement in space. Further addition of lutein led to the formation of red precipitates. The molar ratio of lutein-to-ovalbumin in the soluble complex obtained at a mixing ratio of 0.45 was 8, while that of the precipitate rose from 25 to 35 with a higher mixing ratio. Eighty-five percent of the soluble complex was precipitated when centrifuged at 5200 rpm for 15 hours, and the complex remaining in the supernatant had an apparent molecular weight of about 720, 000. These results indicate that lutein and some proteins interact non-stoichiometrically to form complexes heterogeneous with respect to aggregation number.

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Alkane is the major constituent of epicuticular wax universally distributed in plants. Tobacco leaves contained 5_??_10mg of alkane per 1000cm². The content gradually increased with leaf age. Leaves on the upper stalk contained more alkane than those on lower stalk. Components with carbon numbers from 27 to 33 occupied more than 98% of the total alkane content. In relative ratios of alkane components, anteiso-C₃₀ and normal-C₃₁ were most drastically and increased, respectively, with leaf age regardless of stalk position. On the other hand, normal-C₂₉ and normal-C₃₃ increased and decreased, respectively, from the upper to lower stalk positions without being affected by leaf age. These results suggest the possible use of alkane composition as an index of leaf maturity and stalk position, for example, the ratio of anteiso-C₃₀/normal-C₃₁ for maturity and normal-C₃₃/normal-C₂₉ for stalk position.

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A simple and sensitive spectrophotometric method for determining meso-α, ε-diaminopime-late with meso-α, ε-diaminopimelate D-dehydrogenase (EC class 1.4.1) is described. meso-α, ε-Diaminopimelate was determined spectrophotometrically with the enzyme by measuring the NADPH formed (Procedure A) or the formazan produced by NADPH (Procedure B). A linear relationship was established between absorbance and the amount of amino acid (0.02_??_0.20 μmol). This method can be used to assay diaminopimelate epimerase (EC 5.1.1.7) and is applicable for determining meso-α, ε-diaminopimelate specifically in hydrolyzates of bacterial cell wall.

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N-acetylmuramyl-L-alanine amidase was obtained from exponentially growing Bacillus subtilis cells. The preparation contained two fractions whose molecular weights were 110, 000 and 220, 000. The two fractions had the same amidase activity and equally accelerated cell wall turnover of autolytic enzyme-deficient mutant cells. But the fraction with the lower molecular weight was more effective in dechaining the cell-chains of mutant cells.

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2-Hydroxy-3-p-tolyl-2-cyclopentenone (7), a potential starting material for synthesis of isolaurene (1), was prepared by photolysis of 2-p-toluenesulfonyloxy-2-cyclopentenone (6). Conversion of 7 into 2, 5-dimethyl-2-p-tolyl-cyclopentanone (14) was carried out as follows. Methylation of 7 with methyl iodide gave 2-methoxy-3-p-tolyl-2-cyclopentanone (9), and the treatment of (9) with methyl magnesium iodide afforded 2-methyl-5 p-tolyl-2-cyclopentenone (11). This compound was allowed to react with methyl iodide in the presence of sodium methoxide to yield 2, 5-dimethyl-2 p-tolyI-4-cyclopentenone (13), the hydrogenation of which over palladium charcoal gave 14.

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The aroma constituents of the highest quality pouchong tea were characterized by GC-MS. Forty-eight components, including five newly identified compounds were characterized. GC peak area percentages of the main components in pouchong tea were compared with those of jasmine tea to differentiate compounds contributing to the aroma characteristics of pouchong tea with superior floral elegant flavor. Nerolidol, jasmine lactone, methyl jasmonate, indole, benzyl cyanide and linalool oxides were found in much higher concentration in pouchong tea than in jasmine tea. These compounds seemed to contribute to the aroma characteristics of the highest quality pouchong tea.

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Methyl N-(substituted benzoyl)anthranilates were found to possess inhibitory activity against the powdery mildew of cucumber caused by Sphaerotheca fuliginea. Both the anthranilate and the N-benzoyl moieties were essential for this type of fungicidal activity. Substitution at the 2- and 4-positions of the N-benzoyl group was unfavorable to the activity except for the 4-methoxy group. Substitution at the 3-position varied the fungicidal activity to various extents. The variation in the activity of 3-substituted derivatives was analyzed quantitatively with substituent parameters and regression analysis indicating that the variation in the steric dimension of substituents was most responsible for the activity.

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The antifungal activity of 37 N-(methoxy-substituted benzoyl)anthranilic esters was tested on the powdery mildew of barley caused by Erysiphe graminis by the pot test. Among the methyl N-(methoxy-substituted benzoyl)anthranilates tested, 3, 4-dimethoxybenzoyl derivative exhibited the highest activity. The variation in fungicidal activity of N-(3, 4-dimethoxy-benzoyl)anthranilic esters was shown to be related with variation in hydrophobicity and the electronic property of the alcohol moiety of the ester. The branching at the α-position of the alcohol moiety of the ester was detrimental to the activity.

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The susceptibility of wheat glutenin to enzymatic hydrolysis has been examined to obtain information on structural properties of the glutenin molecule. Native glutenin was prepared under mild conditions to avoid denaturation of glutenin. The obtained glutenin was hydro-lyzed with trypsin, chymotrypsin, sobtilisin or pepsin. The extent of hydrolysis was analyzed by discontinuous sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis. Native glutenin was hydrolyzed at a very fast rate with the enzymes. All subunits of glutenin disappeared early in hydrolysis and no obvious difference was observed in the rate of hydrolysis among these subunits. The reduction of disulfide bonds of glutenin and the denaturation of glutenin by treatment with 8M urea, SDS or heating did not affect the hydrolysis profiles. The results suggest that glutenin may have an unfolded structure rather than a rigid structure and that subunits of native glutenin were exposed equally to the solvent.

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Twenty-nine mercaptotriazinone derivatives were synthesized and their plant growthpromoting activities were examined by the rice (Oryza saliva) seedling test in the presence or absence of gibberellic acid (GA₃). For high activity in promoting the GA₃-induced shoot elongation, an isopropyl or an appropriately substituted phenyl group, a hydrogen atom and a lower alkyl thio group were required in the 1-, 3- and 4-positions, respectively, of the 1, 3, 5-triazine-2, 6-dione structure. In more detailed experiments, 4-methylthio-l-(p-tolyl)-s-triazine-2, 6(1H, 3H)-dione, one of the most potent mercaptotriazinones, was found to synergistically promote the GA₃-induced elongation of the first and second leaves of rice seedlings. Several mercaptotriazinone derivatives, active or inactive, in the rice seedling test were examined by the radish (Raphanus sativus) leaf disk expansion test, but all of them were completely inactive. Structure-activity relationships of mercaptotriazinone derivatives are discussed in relation to those of the corresponding alkoxytriazinone derivatives.

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On irradiation with UV light the fungicide isoprothiolane (diisopropyl 1, 3-dithiolan-2-ylidenemalonate) decomposed rapidly on the silica gel surface. The degradation pathways involved dithiolane ring cleavage, ester hydrolysis, decarboxylation, heterocycles formation such as dithietane and trithiolane, and sulfur liberation. The photoproducts confirmed were oxalic acid, dithiolanylidenemalonic acid, dithiolanylideneacetic acid, 2, 4-bis[bis(isopropoxycar-bonyl)methylene]-1, 3-dithietane, 3, 5-bis[bis(isopropoxy-carbonyl)methylene]-1, 2, 4-trithiolane and sulfur. The methyl and ethyl homologs of isoprothiolane similarly gave the correspond-ing photoproducts. The surface area where isoprothiolane was placed appeared to be related closely with the photolysis rate. Isoprothiolane decomposed much more rapidly on sand than on a glass plate. This surface effect was greatly depressed under nitrogen atmosphere. Similar phenomena were observed with some other pesticides, with particularly those con-taining sulfur atoms in the molecule.

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A low salt-soluble, diffusible fraction of meat was separated into basic, neutral and acidic fractions. Investigations were then conducted on the reaction of each fraction with nitrite and on the recovery of the added nitrite.
The basic fraction shared the lowest ability to decompose nitrite and had 88 % recovery of added nitrite-N. Hypoxanthine was one of the main components that affected the recovery in the basic fraction. In the neutral fraction, 42%. of nitrite was decomposed, and the recovery of the nitrite was 107%. In the acidic fraction, more than 80% of nitrite was decomposed and 30% was converted to unidentified-N compounds. Among endogenous acidic sub-stances tested, cysteic acid showed the highest ability to decompose nitrite, accompanying the production of unidentified-N compounds.

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Scanning electron microscopy and rigidity characterization were used in this study of myosin gelation in the presence of actin. The heat-induced gel formation of myosin was aided by the addition of actin to myosin at a molar ratio of 1:2.7. However, this actin effect was not observed when the actin-binding site(s) of myosin was blocked by p-chloromercuri-benzoate treatment or denaturation, or when the myosin-binding site(s) of actin was blocked by trinitrophenylation.
The effect also disappeared with an aging myosin-actin mixture, with ATP or pyro-phosphate as dissociating agent prior to thermal treatment of the system.
The present findings indicate the indispensability of myosin binding to actin for enhancing the thermal gelation of myosin. The gelation process appears to involve a large electrostatic contribution, as well as such chemical reactions as oxidation of SH groups.

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